Sex Differences in Mental Abilities: "g" Masks the Dimensions on Which They Lie
ERIC Educational Resources Information Center
Johnson, Wendy; Bouchard, Thomas J., Jr.
2007-01-01
Empirical data suggest that there is at most a very small sex difference in general mental ability, but men clearly perform better on visuospatial tasks while women clearly perform better on tests of verbal usage and perceptual speed. In this study, we integrated these overall findings with predictions based on the Verbal-Perceptual-Rotation (VPR)…
[Lopinavir/ritonavir in human immunodeficiency virus-infected women].
Téllez, María Jesús
2014-11-01
There are clear sex-related biological differences between men and women. Diseases that affect the two sexes differently are studied separately. However, some diseases affect both men and women, but their incidence or outcome are clearly different. In human immunodeficiency virus infection, the potential differences in the effects of antiretroviral therapy are poorly characterized and few studies have been designed to elucidate these differences. Moreover, women are usually poorly represented in clinical trials of antiretroviral drugs. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.
Career Plans of Men and Women in Gender-Dominant Professions.
ERIC Educational Resources Information Center
Shann, Mary H.
1983-01-01
Investigated sex differences in career plans of graduate students (N=559) completing training in male- and female-dominated professions. Analyses showed clear patterns of sex differences in the feminine professions. Except for child care, the plans of women in male-dominated groups were not significantly different from those of male colleagues.…
Gender and Sex Education: A Study of Adolescent Responses.
ERIC Educational Resources Information Center
Measor, Lynda; And Others
1996-01-01
Responses of English adolescents to single-sex sex education classes were studied, focusing on about 20 females and about 20 males. There were clear gender differences in student reactions, with boys responding more openly, disruptively, and negatively. The role of cultural prescriptions in their responses is explored. (SLD)
Sex differences in cerebral palsy on neuromotor outcome: a critical review.
Romeo, Domenico M; Sini, Francesca; Brogna, Claudia; Albamonte, Emilio; Ricci, Daniela; Mercuri, Eugenio
2016-08-01
Sex differences have been reported in children with cerebral palsy (CP), with males having a higher risk of developing CP, but it is not entirely clear whether sex may also affect the severity of motor impairment. The aim of the present study was to critically review the existing literature on sex influence on neuromotor outcome in children with CP. The published papers confirm that CP occurs more frequently in males than in females. Within different types of CP or individual level of impairment, however, there was limited evidence that sex also had an effect on their performance. © 2016 Mac Keith Press.
Sex differences and hormonal effects on gut microbiota composition in mice.
Org, Elin; Mehrabian, Margarete; Parks, Brian W; Shipkova, Petia; Liu, Xiaoqin; Drake, Thomas A; Lusis, Aldons J
2016-07-03
We previously reported quantitation of gut microbiota in a panel of 89 different inbred strains of mice, and we now examine the question of sex differences in microbiota composition. When the total population of 689 mice was examined together, several taxa exhibited significant differences in abundance between sexes but a larger number of differences were observed at the single strain level, suggesting that sex differences can be obscured by host genetics and environmental factors. We also examined a subset of mice on chow and high fat diets and observed sex-by-diet interactions. We further investigated the sex differences using gonadectomized and hormone treated mice from 3 different inbred strains. Principal coordinate analysis with unweighted UniFrac distances revealed very clear effects of gonadectomy and hormone replacement on microbiota composition in all 3 strains. Moreover, bile acid analyses showed gender-specific differences as well as effects of gonodectomy, providing one possible mechanism mediating sex differences in microbiota composition.
Sex differences in the response to apomorphine in rats.
Masur, J; Boerngen, R; Tufik, S
1980-01-01
The response of male and female rats to the hypothermic and verticalization effect (climbing behavior) induced by different doses of apomorphine was studied. A clear sex difference was observed, males showing more verticalization than females. Conversely the females showed a greater decrease in body temperature than males. The verticalization response was also studied in rats of both sexes at seven different ages, varying from 15 to 100 days. At the earlier ages, both groups presented low levels of verticalization. Mature males (60-100 days of age) increased the verticalization response to apomorphine.
The Role of Sex in Memory Function: Considerations and Recommendations in the Context of Exercise.
Loprinzi, Paul D; Frith, Emily
2018-05-31
There is evidence to suggest that biological sex plays a critical role in memory function, with sex differentially influencing memory type. In this review, we detail the current evidence evaluating sex-specific effects on various memory types. We also discuss potential mechanisms that explain these sex-specific effects, which include sex differences in neuroanatomy, neurochemical differences, biological differences, and cognitive and affect-related differences. Central to this review, we also highlight that, despite the established sex differences in memory, there is little work directly comparing whether males and females have a differential exercise-induced effect on memory function. As discussed herein, such a differential effect is plausible given the clear sex-specific effects on memory, exercise response, and molecular mediators of memory. We emphasize that future work should be carefully powered to detect sex differences. Future research should also examine these potential exercise-related sex-specific effects for various memory types and exercise intensities and modalities. This will help enhance our understanding of whether sex indeed moderates the effects of exercise and memory function, and as such, will improve our understanding of whether sex-specific, memory-enhancing interventions should be developed, implemented, and evaluated.
School Leadership, Sex and Gender: Welcome to Difference
ERIC Educational Resources Information Center
Kruger, Meta L.
2008-01-01
The biological basis for differences between the sexes has become increasingly clear in recent years. The nature-nurture debate has made way for the view that the individual is a product of the interaction between genes and environment. For the world of school leadership this means that instead of arguing about them, we should acknowledge the…
2016-10-01
Operational Performance and Sex -Specific Responses PRINCIPAL INVESTIGATOR: Brent C. Ruby CONTRACTING ORGANIZATION: The University of Montana System...Environments: Implications for Enhanced Training, Operational Performance and Sex -Specific Responses 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-15-2-0075...mitochondrial gene responses were not altered by altitude stress. Moreover, there were no differences across sex . While prior research has clearly
Role of Microbiota in Sexually Dimorphic Immunity.
Elderman, Marlies; de Vos, Paul; Faas, Marijke
2018-01-01
Sex differences in peripheral immune responses are well recognized. This is associated with sex differences in many immunological diseases. As the intestinal microbiota is known to influence the immune system, such sex differences in immune responses may be a consequence of sex-specific microbiota. Therefore, this mini-review discusses sex differences in intestinal microbiota and the possible role of microbiota in shaping sexually dimorphic immunity. Sex differences in microbiota composition are clearly found in mice studies and also in human studies. However, the lack of standardization in human studies may mask the sexual dimorphism in microbiota composition in human studies, since many factors such as age, genetic background, BMI, diet, and sex hormones appear to interfere with the sexual dimorphism in microbiota composition. Only a few mice studies found that differences in gut microbiota composition are causative for some aspects of sexually dimorphic immunity. Therefore, future studies should focus on a causal relationship between sexually dimorphic immunity and microbiota, considering the abovementioned interfering confounding factors. This would benefit the development of more sex-specific effective treatment options for immunological diseases.
Richter-Appelt, Hertha; Discher, Christine; Gedrose, Benjamin
2005-09-01
The concept of intersexuality subsumes a wide variety of phenomena with very specific underlying causes. In all these cases, an untypical development takes place during the prenatal sex differentiation process becoming clinically manifest, either at, or soon after birth or at the time of puberty. It subsumes conditions in which biological sexual characteristics (e.g. chromosomal sex, gonadal sex, hormonal sex, morphological sex) differ from each other and one person cannot easily be assigned to one sex. One of the main goals of medical treatment of persons with intersex-syndroms is the development of a stable gender identity. Over the last few years, sex (and gender) assignment of persons with different forms of intersexuality has become a much discussed topic. An interesting--and very obviously observable--variable that was brought in connection with sex assignment is gender related childhood play behaviour. The purpose of the presented study is to examine 37 persons with different forms of intersexuality (disturbances of androgen biosynthesis, partial and complete androgen insensitivity, gonadal dysgenesis with 46,XY and congenital adrenal hyperplasia with 46,XX) with regard to gender identity and gender role behaviour in childhood. Not all subjects in the study group had developed a clear female or male gender identity. In contrast to previous studies, some persons with CAIS did not recall distinguished female childhood play behaviour and these persons did not show a clear female gender identity. In contrast to results from other studies, the CAH-affected girls in this study did not seem to recall masculinized behaviour. Further research is needed to guarantee better psychosexual development with good quality of life in individuals with intersexuality.
Sex differences in oral asymmetries during wordrepetition.
Hausmann, M; Behrendt-Körbitz, S; Kautz, H; Lamm, C; Radelt, F; Güntürkün, O
1998-12-01
During speech production the right side of the mouth is opened to a larger degree in most people. This facial asymmetry is thought to be related to a left hemisphere dominance in language processing and/or motor programming. We investigated asymmetrical lip separations during discrete or serial word productions in right handed persons. The results revealed a right sided lip separation bias in both genders during discrete word production in which the words had to be uttered once. As soon as the words had to be produced continuously, however, a clear sex difference appeared with males having the usual right bias but females now showing no clear asymmetry, with a tendency for larger lip separations on the left side. These results suggest the existence of two separate neural systems from which one controls the discrete task and which is left hemisphere dominant in both genders. The other is probably involved in serial word productions and shows a sex difference with regard to its asymmetry pattern.
The scope and strength of sex-specific selection in genome evolution
Wright, A E; Mank, J E
2013-01-01
Males and females share the vast majority of their genomes and yet are often subject to different, even conflicting, selection. Genomic and transcriptomic developments have made it possible to assess sex-specific selection at the molecular level, and it is clear that sex-specific selection shapes the evolutionary properties of several genomic characteristics, including transcription, post-transcriptional regulation, imprinting, genome structure and gene sequence. Sex-specific selection is strongly influenced by mating system, which also causes neutral evolutionary changes that affect different regions of the genome in different ways. Here, we synthesize theoretical and molecular work in order to provide a cohesive view of the role of sex-specific selection and mating system in genome evolution. We also highlight the need for a combined approach, incorporating both genomic data and experimental phenotypic studies, in order to understand precisely how sex-specific selection drives evolutionary change across the genome. PMID:23848139
Juvenile sex offenders compared to non-sex offenders: a review of the literature 1995-2005.
van Wijk, Anton; Vermeiren, Robert; Loeber, Rolf; 't Hart-Kerkhoffs, Lisette; Doreleijers, Theo; Bullens, Ruud
2006-10-01
An unresolved but clinically important issue in the literature on juvenile delinquency is to what extent juvenile sex offenders resemble non-sex offenders with respect to individual, familial, and environmental characteristics. The current article reviewed published studies (1995-2005) comparing sex offenders with non-sex offenders. The 17 articles meeting the inclusion criteria suggest that differences exist between sex offenders and non-sex offenders on personality characteristics, behavioral problems, history of sexual abuse, nonsexual offending, and peer functioning. Inconsistent results were found for demographic factors, family functioning and background, antisocial attitudes, and intellectual and neurological functioning. Although it is likely that sex offenders can be differentiated from nonsex offenders on a number of characteristics, caution is warranted because of methodological differences between studies and small samples size. Also, studies show that sex offenders are a heterogeneous group. Further research should take into account this heterogeneity by including sex offenders from clearly circumscribed groups and investigating characteristics specifically related to sexual behavior.
Human cells involved in atherosclerosis have a sex.
Franconi, Flavia; Rosano, Giuseppe; Basili, Stefania; Montella, Andrea; Campesi, Ilaria
2017-02-01
The influence of sex has been largely described in cardiovascular diseases. Atherosclerosis is a complex process that involves many cell types such as vessel cells, immune cells and endothelial progenitor cells; however, many, if not all, studies do not report the sex of the cells. This review focuses on sex differences in human cells involved in the atherosclerotic process, emphasizing the role of sex hormones. Furthermore, we report sex differences and issues related to the processes that determine the fate of the cells such as apoptotic and autophagic mechanisms. The analysis of the data reveals that there are still many gaps in our knowledge regarding sex influences in atherosclerosis, largely for the cell types that have not been well studied, stressing the urgent need for a clear definition of experimental conditions and the inclusion of both sexes in preclinical studies. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Lee, Jonathan J; Schultz, Irvin R
2010-01-01
Perfluorooctanoic acid (PFOA) among other perfluorinated acids is becoming recognized as a ubiquitous environmental contaminant. PFOA is resistant to environmental degradation and appears to undergo no biotransformation in animals. Previous toxicokinetic studies in rodents have indicated that urinary excretion is the most important elimination pathway once PFOA has been absorbed. In some species such as rats, large sex-related differences in urinary excretion have been reported, with females having a much shorter blood or plasma elimination half-life than that of males. It is unknown whether this phenomenon occurs in fish. Therefore, this study determined the disposition of PFOA in male and female fathead minnows (Pimephales promelas) after a single oral dose of PFOA. After dosing, minnows were subsequently euthanized at various times until 336 h postdosing and the PFOA concentration was measured in plasma, gonads, and fish carcass. The concentration-time profiles of PFOA were then analyzed using toxicokinetic methods. The results indicated a clear sex difference in the elimination of PFOA. The plasma elimination half-life of PFOA in female minnows was 6.3 h while in male minnows it was 68.5 h. Pretreatment of female minnows with the synthetic androgen trenbolone substantially delayed the elimination of PFOA, causing the elimination half-life to increase to 25.3 h. In males, pretreatment with the synthetic estrogen ethynylestradiol (EE2) had little effect on PFOA toxicokinetics. These results indicate that the sex differences in PFOA elimination in fathead minnows can at least partially be modulated by exposure to synthetic sex steroids. Whether sex differences in PFOA elimination in minnows is attributable to differences in renal transport activity, as it appears to be for rodents, is unknown at present but clearly warrants further study.
Sex-specific lateralization of event-related potential effects during mental rotation of polygons.
Pellkofer, Julia; Jansen, Petra; Heil, Martin
2014-08-06
Mental rotation performance has been found to produce one of the largest sex differences in cognition. Many theories suggest that this effect should be accompanied by a sex difference in functional cerebral asymmetry, but empirical data are more than equivocal probably because of (a) the use of inappropriate stimuli and (b) insufficient power of most neurophysiological studies. Therefore, sex differences in mental rotation of polygons were investigated in 122 adults. Men outperformed women on mental rotation speed (as well as on response time and accuracy). On the basis of the electrophysiological brain correlates of mental rotation, we observed a bilateral brain activity for men, whereas women's brain activity was clearly lateralized toward the left hemisphere if and only if mental rotation was involved. Thus, sex differences in functional cerebral asymmetry can indeed be observed if appropriate stimuli are used in a sufficiently large sample.
Barnett, Melissa A.; Scaramella, Laura V.
2014-01-01
Sex differences in rates of behavior problems, including internalizing and externalizing problems, begin to emerge during early childhood. These sex differences may occur because mothers parent their sons and daughters differently, or because the impact of parenting on behavior problems is different for boys and girls. This study examines whether associations between observations of mothers’ positive and negative parenting and children’s externalizing and internalizing behaviors vary as a function of child sex. The sample consists of 137 African American, low-income families with one sibling approximately two-years-old and the closest aged older sibling who is approximately four-years-old. Results from fixed-effects within-family models indicate clear sex differences regardless of child age. Mothers were observed to use less positive parenting with sons than with daughters. Higher levels of observed negative parenting were linked to more externalizing behaviors for boys, while lower levels of positive parenting were linked to more externalizing behaviors for girls. No child sex differences emerged regarding associations between observed positive and negative parenting and internalizing behaviors. PMID:23937420
Sex differences in the reciprocal behaviour of children with autism.
Backer van Ommeren, Tineke; Koot, Hans M; Scheeren, Anke M; Begeer, Sander
2017-08-01
Differences in the social limitations of girls compared to boys on the autism spectrum are still poorly understood. Impaired social-emotional reciprocity is a core diagnostic criterion for an autism spectrum disorder. This study compares sex differences in reciprocal behaviour in children with autism spectrum disorder (32 girls, 114 boys) and in typically developing children (24 girls, 55 boys). While children with autism spectrum disorder showed clear limitations in reciprocal behaviour compared to typically developing children, sex differences were found only in the autism spectrum disorder group: girls with autism spectrum disorder had higher reciprocity scores than boys with autism spectrum disorder. However, compared to typically developing girls, girls with autism spectrum disorder showed subtle differences in reciprocal behaviour. The sex-specific response patterns in autism spectrum disorder can inform and improve the diagnostic assessment of autism in females.
RAS and sex differences in diabetic nephropathy.
Clotet, Sergi; Riera, Marta; Pascual, Julio; Soler, Maria José
2016-03-09
The incidence and progression of kidney diseases are influenced by sex. The renin-angiotensin system (RAS) is an important regulator of cardiovascular and renal function. Sex differences in the renal response to RAS blockade have been demonstrated. Circulating and renal RAS has been shown to be altered in type 1 and type 2 diabetes; this enzymatic cascade plays a critical role in the development of diabetic nephropathy (DN). Angiotensin converting enzyme (ACE) and ACE2 are differentially regulated depending on its localization within the diabetic kidney. Furthermore, clinical and experimental studies have shown that circulating levels of sex hormones are clearly modulated in the context of diabetes, suggesting that sex-dependent RAS regulation may be also be affected in these individuals. The effect of sex hormones on circulating and renal RAS may be involved in the sex differences observed in DN progression. In this paper we will review the influence of sex hormones on RAS expression and its relation to diabetic kidney disease. A better understanding of the sex dimorphism on RAS might provide a new approach for diabetic kidney disease treatment. Copyright © 2015, American Journal of Physiology - Renal Physiology.
McNamara, John M.; Wolf, Max
2015-01-01
Strong asymmetries in parental care, with one sex providing more care than the other, are widespread across the animal kingdom. At present, two factors are thought to ultimately cause sex differences in care: certainty of parentage and sexual selection. By contrast, we here show that the coevolution of care and the ability to care can result in strong asymmetries in both the ability to care and the level of care, even in the absence of these factors. While the coevolution of care and the ability to care does not predict which sex evolves to care more than the other, once other factors give rise to even the slightest differences in the cost and benefits of care between the sexes (e.g. differences in certainty in parentage), a clear directionality emerges; the sex with the lower cost or higher benefit of care evolves both to be more able to care and to provide much higher levels of care than the other sex. Our findings suggest that the coevolution of levels of care and the ability to care may be a key factor underlying the evolution of sex differences in care. PMID:25694618
Compère, Laurie; Rari, Eirini; Gallarda, Thierry; Assens, Adèle; Nys, Marion; Coussinoux, Sandrine; Machefaux, Sébastien; Piolino, Pascale
2018-01-01
A recently tested hypothesis suggests that inter-individual differences in episodic autobiographical memory (EAM) are better explained by individual identification of typical features of a gender identity than by sex. This study aimed to test this hypothesis by investigating sex and gender related differences not only in EAM but also during retrieval of more abstract self-knowledge (i.e., semantic autobiographical memory, SAM, and conceptual self, CS), and considering past and future perspectives. No sex-related differences were identified, but regardless of the sex, feminine gender identity was associated with clear differences in emotional aspects that were expressed in both episodic and more abstract forms of AM, and in the past and future perspectives, while masculine gender identity was associated with limited effects. In conclusion, our results support the hypothesis that inter-individual differences in AM are better explained by gender identity than by sex, extending this assumption to both episodic and semantic forms of AM and future thinking. Copyright © 2017 Elsevier Inc. All rights reserved.
The genomics of plant sex chromosomes.
Vyskot, Boris; Hobza, Roman
2015-07-01
Around six percent of flowering species are dioecious, with separate female and male individuals. Sex determination is mostly based on genetics, but morphologically distinct sex chromosomes have only evolved in a few species. Of these, heteromorphic sex chromosomes have been most clearly described in the two model species - Silene latifolia and Rumex acetosa. In both species, the sex chromosomes are the largest chromosomes in the genome. They are hence easily distinguished, can be physically separated and analyzed. This review discusses some recent experimental data on selected model dioecious species, with a focus on S. latifolia. Phylogenetic analyses show that dioecy in plants originated independently and repeatedly even within individual genera. A cogent question is whether there is genetic degeneration of the non-recombining part of the plant Y chromosome, as in mammals, and, if so, whether reduced levels of gene expression in the heterogametic sex are equalized by dosage compensation. Current data provide no clear conclusion. We speculate that although some transcriptome analyses indicate the first signs of degeneration, especially in S. latifolia, the evolutionary processes forming plant sex chromosomes in plants may, to some extent, differ from those in animals. Copyright © 2015. Published by Elsevier Ireland Ltd.
Sexual conflict resolved by invasion of a novel sex determiner in Lake Malawi cichlid fishes.
Roberts, Reade B; Ser, Jennifer R; Kocher, Thomas D
2009-11-13
Sex determination mechanisms differ among animal species, but it is not clear how these differences evolve. New sex determiners may arise in response to sexual conflicts, which occur when traits benefit one sex but hinder the other. We identified the genetic basis for the orange-blotch (OB) color pattern, a trait under sexually antagonistic selection in the cichlid fish of Lake Malawi, East Africa. The OB phenotype is due to a cis-regulatory mutation in the Pax7 gene. OB provides benefits of camouflage to females but disrupts the species-specific male color patterns used for mate recognition. We suggest that the resulting sexual conflict over the OB allele has been resolved by selection for a novel female sex determination locus that has invaded populations with an ancestral male sex determination system.
The Relation of Sex Role Stereotyping to Body Image.
ERIC Educational Resources Information Center
Guy, Rebecca F.; And Others
1980-01-01
Findings suggest that the male mesomorph is clearly sex-typed masculine, while the female ectomorph is clearly sex-typed feminine. The remaining male and female body types appear to be "androgynous." (Author/DB)
ERIC Educational Resources Information Center
Weirich, Melanie; Fuchs, Susanne; Simpson, Adrian; Winkler, Ralf; Perrier, Pascal
2016-01-01
Purpose: Mumbling as opposed to clear speech is a typical male characteristic in speech and can be the consequence of a small jaw opening. Whereas behavioral reasons have often been offered to explain sex-specific differences with respect to clear speech, the purpose of this study is to investigate a potential anatomical reason for smaller jaw…
Cardiovascular biomarkers and sex: the case for women.
Daniels, Lori B; Maisel, Alan S
2015-10-01
Measurement of biomarkers is a critical component of cardiovascular care. Women and men differ in their cardiac physiology and manifestations of cardiovascular disease. Although most cardiovascular biomarkers are used by clinicians without taking sex into account, sex-specific differences in biomarkers clearly exist. Baseline concentrations of many biomarkers (including cardiac troponin, natriuretic peptides, galectin-3, and soluble ST2) differ in men versus women, but these sex-specific differences do not generally translate into a need for differential sex-based cut-off points. Furthermore, most biomarkers are similarly diagnostic and prognostic, regardless of sex. Two potential exceptions are cardiac troponins measured by high-sensitivity assay, and proneurotensin. Troponin levels are lower in women than in men and, with the use of high-sensitivity assays, sex-specific cut-off points might improve the diagnosis of myocardial infarction. Proneurotensin is a novel biomarker that was found to be predictive of incident cardiovascular disease in women, but not men, and was also predictive of incident breast cancer. If confirmed, proneurotensin might be a unique biomarker of disease risk in women. With any biomarker, an understanding of sex-specific differences might improve its use and might also lead to an enhanced understanding of the physiological differences between the hearts of men and women.
Sex differences in Hadza eating frequency by food type.
Berbesque, J Colette; Marlowe, Frank W; Crittenden, Alyssa N
2011-01-01
We investigate sex differences in frequencies of adults eating in a foraging population-the Hadza of Tanzania. We use eating frequency data from instantaneous scan observations of the Hadza, to see to how much sharing of foods taken back to camp compensates for the targeting of different foods by each sex while out foraging. Eating in camp differs by sex in terms of overall eating frequency, as well as in terms of diet composition (frequencies of eating each food type). We also control for sex-differences in time spent in camp and still find sex-differences in eating frequencies-women are observed eating significantly more frequently than men. There are also sex-differences in the eating frequencies of particular food types both with and without controlling for presence in camp. Finally, we use data on acquisition of each food type by sex and find that both sexes are more frequently observed eating women's foods in camp than men's foods. At least in the case of the Hadza, we see pronounced sex differences in the in-camp diet. Hadza men are eating a higher quality diet than are women, but women are able to eat far more frequently, and spend less time foraging than men. It is not yet clear whether a regular caloric intake of lower quality foods would be more beneficial for maintaining fecundity than a more variable diet consisting of higher quality foods. Copyright © 2011 Wiley-Liss, Inc.
Quantitative analysis of pre-and postsynaptic sex differences in the nucleus accumbens
Forlano, Paul M.; Woolley, Catherine S.
2010-01-01
The nucleus accumbens (NAc) plays a central role in motivation and reward. While there is ample evidence for sex differences in addiction-related behaviors, little is known about the neuroanatomical substrates that underlie these sexual dimorphisms. We investigated sex differences in synaptic connectivity of the NAc by evaluating pre- and postsynaptic measures in gonadally intact male and proestrous female rats. We used DiI labeling and confocal microscopy to measure dendritic spine density, spine head size, dendritic length and branching of medium spiny neurons (MSNs) in the NAc, and quantitative immunofluorescence to measure glutamatergic innervation using pre- (vesicular glutamate transporter 1 and 2) and postsynaptic (post synaptic density 95) markers, as well as dopaminergic innervation of the NAc. We also utilized electron microscopy to complement the above measures. Clear but subtle sex differences were identified, namely in distal dendritic spine density and the proportion of large spines on MSNs, both of which are greater in females. Sex differences in spine density and spine head size are evident in both the core and shell subregions, but are stronger in the core. This study is the first demonstration of neuroanatomical sex differences in the NAc and provides evidence that structural differences in synaptic connectivity and glutamatergic input may contribute to behavioral sex differences in reward and addiction. PMID:20151363
The scope and strength of sex-specific selection in genome evolution.
Wright, A E; Mank, J E
2013-09-01
Males and females share the vast majority of their genomes and yet are often subject to different, even conflicting, selection. Genomic and transcriptomic developments have made it possible to assess sex-specific selection at the molecular level, and it is clear that sex-specific selection shapes the evolutionary properties of several genomic characteristics, including transcription, post-transcriptional regulation, imprinting, genome structure and gene sequence. Sex-specific selection is strongly influenced by mating system, which also causes neutral evolutionary changes that affect different regions of the genome in different ways. Here, we synthesize theoretical and molecular work in order to provide a cohesive view of the role of sex-specific selection and mating system in genome evolution. We also highlight the need for a combined approach, incorporating both genomic data and experimental phenotypic studies, in order to understand precisely how sex-specific selection drives evolutionary change across the genome. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.
Sewell, Kelsey K; McGarrity, Larissa A; Strassberg, Donald S
2017-09-01
Prior research has examined how heterosexual individuals define sex; however, these studies have rarely focused on sexual minority individuals or included a full range of applicable sexual behaviors. Participants were recruited from a local Pride Festival across two years. Study 1 (N = 329) was primarily descriptive and examined which physically intimate behaviors lesbian, gay, and bisexual (LGB) participants included in their definitions of sex and the behaviors in which they had previously engaged. Study 2 (N = 393) utilized a between-subjects design to assess differences in definitions of sex when judging one's own behavior compared with that of a partner outside of the relationship. The behaviors in which participants were most likely to have engaged were manual-genital (82%) and oral-genital stimulation (79%). Regarding definitions of sex, a clear "gold standard" emerged for men, with 90% endorsing penile-anal intercourse as sex. No equally clear standard existed for women. Participants who were asked to consider their partner's behavior outside of their relationship were more likely to endorse the behavior as "having sex" than participants asked to consider their own behavior. This study addressed a major limitation of prior research by investigating definitions of sex among a community sample of LGB adults, with implications for provision of health care and sexual agreements between same-sex couples.
Horowitz, Ava D; Spicer, Louise
2013-01-01
Research into definitions of "having sex" has tended to employ a dichotomous response design (following Sanders & Reinisch, 1999). However, conceptions of sexual activity may be far less clear-cut (c.f. Faulkner, 2003 ; Peterson & Muehlenhard, 2007). More refinement is also needed regarding the impact of sexual orientation on the construction of what counts as sex. This research employed a continuous response design, asking 124 emerging adults (40 male heterosexuals, 42 female heterosexuals, & 42 lesbians) to judge 13 sexual acts using a graded, six-point scale. Overall, there was substantial agreement that intercourse (vaginal and anal) was "definitely," and kissing "definitely not," sex. However, across the various acts, participants also consistently made use of options between these extremes, such that a clear hierarchy of sexual behaviors emerged. The lesbian group considered a range of forms of genital stimulation to be significantly more constitutive of sex than either heterosexual group, while judgments by male and female heterosexuals did not significantly differ for any listed act. The implications of graded definitions of sex, a hierarchy of sexual behaviors, and the role of sexual behaviors in hetero- and homosexual identity management are explored.
Neural Control of the Circulation: How Sex and Age Differences Interact in Humans
Joyner, Michael J.; Barnes, Jill N.; Hart, Emma C.; Wallin, B. Gunnar; Charkoudian, Nisha
2015-01-01
The autonomic nervous system is a key regulator of cardiovascular system. In this review we focus on how sex and aging influence autonomic regulation of blood pressure in humans in an effort to understand general issues related to how the autonomic nervous system regulates blood pressure, and the cardiovascular system as a whole. Younger women generally have lower blood pressure and sympathetic activity than younger men. However, both sexes show marked inter-individual variability across age groups with significant overlap seen. Additionally, while men across the lifespan show a clear relationship between markers of whole body sympathetic activity and vascular resistance, such a relationship is not seen in young women. In this context, the ability of the sympathetic nerves to evoke vasoconstriction is lower in young women likely as a result of concurrent β2 mediated vasodilation that offsets α-adrenergic vasoconstriction. These differences reflect both central sympatho-inhibitory effects of estrogen and also its influence on peripheral vasodilation at the level of the vascular smooth muscle and endothelium. By contrast post-menopausal women show a clear relationship between markers of whole body sympathetic traffic and vascular resistance, and sympathetic activity rises progressively in both sexes with aging. These central findings in humans are discussed in the context of differences in population-based trends in blood pressure and orthostatic intolerance. The many areas where there is little sex-specific data on how the autonomic nervous system participates in the regulation of the human cardiovascular system are highlighted. PMID:25589269
Miller, Virginia M; Bahn, Rebecca S
2013-09-01
Initiatives to hasten the translation of basic science discoveries to clinical care have necessitated the development of new approaches to interdisciplinary collaboration and training of future investigators. This has been nowhere more important than in the study of sex differences with implications for extension into areas of gender medicine. Clearly, gaining better understanding of the role that sex and gender play in health and disease is essential to the implementation of truly individualized medicine. This case report will describe our experiences in developing the Mayo Clinic Building Interdisciplinary Research Programs in Women's Health (BIRCWH) program, an interdisciplinary research and training program in women's health and sex and gender differences. We identify both our successes and the barriers we have encountered in order that others who are developing similar programs might benefit from our experiences.
[Pain medicine from intercultural and gender-related perspectives].
Schiltenwolf, M; Pogatzki-Zahn, E M
2015-10-01
Cultural setting and sex and gender of the patient are important factors affecting the occurrence, severity, clinical course and prognosis of pain and pain-related diseases. Intercultural differences in the perception and verbal expression of symptoms and emotional function are fundamental and it is important to realize these differences in order to understand patients with a migration background. A trusting doctor-patient relationship is generally very sensitive and it is even more difficult to establish when differences in the cultural background impair mutual understanding. Regarding sex and gender there is evidence that females are more susceptible to developing chronic pain conditions, experience more severe pain and respond differently to pain therapy; however, results of recent studies indicate that females are not that different to males when comparing several modalities of experimental pain (although some differences exist). Similarly, sex and gender differences in postoperative pain seem to exist but the differences are relatively small when pain scores are compared. Other aspects, such as the response to analgesics and role of psychosocial factors should be addressed when sex and gender aspects are studied. Similarly, sex and gender differences in the prevalence of chronic pain exist but the results of some studies, e.g. those controlling for confounders, are not very clear. Research is needed to delineate the role of specific aspects affecting sex and gender differences and the underlying mechanisms (e.g. reduced inhibitory control, hormones, psychological aspects and social factors). Altogether, we need to open our minds to some intercultural and sex and gender aspects in the clinical setting. For sex and gender differences we may need a more biopsychosocial approach to understand the underlying differences and differentiate between sex and gender and sex and gender-associated aspects for acute and chronic pain.
Rapkin, James; Archer, C Ruth; Grant, Charles E; Jensen, Kim; House, Clarissa M; Wilson, Alastair J; Hunt, John
2017-09-01
There is often large divergence in the effects of key nutrients on life span (LS) and reproduction in the sexes, yet nutrient intake is regulated in the same way in males and females given dietary choice. This suggests that the sexes are constrained from feeding to their sex-specific nutritional optima for these traits. Here, we examine the potential for intralocus sexual conflict (IASC) over optimal protein and carbohydrate intake for LS and reproduction to constrain the evolution of sex-specific nutrient regulation in the field cricket, Teleogryllus commodus. We show clear sex differences in the effects of protein and carbohydrate intake on LS and reproduction and strong positive genetic correlations between the sexes for the regulated intake of these nutrients. However, the between-sex additive genetic covariance matrix had very little effect on the predicted evolutionary response of nutrient regulation in the sexes. Thus, IASC appears unlikely to act as an evolutionary constraint on sex-specific nutrient regulation in T. commodus. This finding is supported by clear sexual dimorphism in the regulated intake of these nutrients under dietary choice. However, nutrient regulation did not coincide with the nutritional optima for LS or reproduction in either sex, suggesting that IASC is not completely resolved in T. commodus. © 2017 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.
Sex differences in depression and anxiety disorders: potential biological determinants.
Altemus, Margaret
2006-11-01
The phenomenon of higher rates of affective disorders in women illustrates many of the difficulties as well as promises of translating preclinical models to human disorders. Abnormalities in the regulation of the hypothalamic-pituitary adrenal axis and the sympathoadrenomedullary system have been identified in depression and anxiety disorders, and these disorders are clearly precipitated and exacerbated by stress. Despite the striking sex difference in the prevalence of depression and anxiety disorders, attempts to identify corresponding sex differences in stress response reactivity in animal models have met with limited success. Processes which may contribute to increased rates of affective disorders in women are greater fluxes in reproductive hormones across the life span, and increased sensitivity to catecholamine augmentation of emotional memory consolidation.
Jaconis, Maryanne; Boyd, Stephen J; Hartung, Cynthia M; McCrea, Sean M; Lefler, Elizabeth K; Canu, Will H
2016-12-01
Although the research is clear that boys with ADHD have higher symptomatology and impairment than girls with ADHD, for adults the research is mixed. Some studies suggest no sex differences, whereas others suggest that women might have higher symptomatology and impairment. The present study examined sex differences in ADHD symptomatology and impairment, and the possible role of claimed and behavioral self-handicapping as an explanation for any differences. Claimed self-handicapping (CSH) involves reports of performance-inhibiting conditions, whereas behavioral self-handicapping (BSH) involves reporting more objective, intentional acts that could undermine performance. College students (N = 699) completed an online study. Sex differences were found for hyperactivity such that women reported higher levels, but not for inattention or impairment. The test of the indirect effect of sex through CSH was significant, suggesting that higher levels of CSH in women were associated with elevated ADHD symptoms and impairment. The test of the indirect effect of sex through BSH was also significant, suggesting that higher levels of BSH in men are associated with elevated symptoms of ADHD and impairment. These data extend the literature by suggesting that self-handicapping might at least partially explain differential self-reporting of ADHD symptoms and impairment in emerging adults across the sexes.
Insights into the mechanisms and the emergence of sex-differences in pain.
Melchior, Meggane; Poisbeau, Pierrick; Gaumond, Isabelle; Marchand, Serge
2016-12-03
Recent studies describe sex and gender as critical factors conditioning the experience of pain and the strategies to respond to it. It is now clear that men and women have different physiological and behavioral responses to pain. Some pathological pain states are also highly sex-specific. This clinical observation has been often verified with animal studies which helped to decipher the mechanisms underlying the observed female hyper-reactivity and hyper-sensitivity to pain states. The role of gonadal hormones in the modulation of pain responses has been a straightforward hypothesis but, if pertinent in many cases, cannot fully account for this complex sensation, which includes an important cognitive component. Clinical and fundamental data are reviewed here with a special emphasis on possible developmental processes giving rise to sex-differences in pain processing. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.
Coretti, Lorena; Cristiano, Claudia; Florio, Ermanno; Scala, Giovanni; Lama, Adriano; Keller, Simona; Cuomo, Mariella; Russo, Roberto; Pero, Raffaela; Paciello, Orlando; Mattace Raso, Giuseppina; Meli, Rosaria; Cocozza, Sergio; Calignano, Antonio; Chiariotti, Lorenzo; Lembo, Francesca
2017-03-28
Alterations of microbiota-gut-brain axis have been invoked in the pathogenesis of autism spectrum disorders (ASD). Mouse models could represent an excellent tool to understand how gut dysbiosis and related alterations may contribute to autistic phenotype. In this study we paralleled gut microbiota (GM) profiles, behavioral characteristics, intestinal integrity and immunological features of colon tissues in BTBR T + tf/J (BTBR) inbred mice, a well established animal model of ASD. Sex differences, up to date poorly investigated in animal models, were specifically addressed. Results showed that BTBR mice of both sexes presented a marked intestinal dysbiosis, alterations of behavior, gut permeability and immunological state with respect to prosocial C57BL/6j (C57) strain. Noticeably, sex-related differences were clearly detected. We identified Bacteroides, Parabacteroides, Sutterella, Dehalobacterium and Oscillospira genera as key drivers of sex-specific gut microbiota profiles associated with selected pathological traits. Taken together, our findings indicate that alteration of GM in BTBR mice shows relevant sex-associated differences and supports the use of BTBR mouse model to dissect autism associated microbiota-gut-brain axis alteration.
Reconceptualizing sex, brain and psychopathology: interaction, interaction, interaction
Joel, D; Yankelevitch-Yahav, R
2014-01-01
In recent years there has been a growing recognition of the influence of sex on brain structure and function, and in relation, on the susceptibility, prevalence and response to treatment of psychiatric disorders. Most theories and descriptions of the effects of sex on the brain are dominated by an analogy to the current interpretation of the effects of sex on the reproductive system, according to which sex is a divergence system that exerts a unitary, overriding and serial effect on the form of other systems. We shortly summarize different lines of evidence that contradict aspects of this analogy. The new view that emerges from these data is of sex as a complex system whose different components interact with one another and with other systems to affect body and brain. The paradigm shift that this understanding calls for is from thinking of sex in terms of sexual dimorphism and sex differences, to thinking of sex in terms of its interactions with other factors and processes. Our review of data obtained from animal models of psychopathology clearly reveals the need for such a paradigmatic shift, because in the field of animal behaviour whether a sex difference exists and its direction depend on the interaction of many factors including, species, strain, age, specific test employed and a multitude of environmental factors. We conclude by explaining how the new conceptualization can account for sex differences in psychopathology. Linked Articles This article is part of a themed section on Animal Models in Psychiatry Research. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-20 PMID:24758640
Relevance of stress and female sex hormones for emotion and cognition.
ter Horst, J P; de Kloet, E R; Schächinger, H; Oitzl, M S
2012-07-01
There are clear sex differences in incidence and onset of stress-related and other psychiatric disorders in humans. Yet, rodent models for psychiatric disorders are predominantly based on male animals. The strongest argument for not using female rodents is their estrous cycle and the fluctuating sex hormones per phase which multiplies the number of animals to be tested. Here, we will discuss studies focused on sex differences in emotionality and cognitive abilities in experimental conditions with and without stress. First, female sex hormones such as estrogens and progesterone affect emotions and cognition, contributing to sex differences in behavior. Second, females respond differently to stress than males which might be related to the phase of the estrous cycle. For example, female rats and mice express less anxiety than males in a novel environment. Proestrus females are less anxious than females in the other estrous phases. Third, males perform in spatial tasks superior to females. However, while stress impairs spatial memory in males, females improve their spatial abilities, depending on the task and kind of stressor. We conclude that the differences in emotion, cognition and responses to stress between males and females over the different phases of the estrous cycle should be used in animal models for stress-related psychiatric disorders.
Rapkin, James; Archer, C. Ruth; Grant, Charles E.; Jensen, Kim; House, Clarissa M.; Wilson, Alastair J.; Hunt, John
2017-01-01
Abstract There is often large divergence in the effects of key nutrients on life span (LS) and reproduction in the sexes, yet nutrient intake is regulated in the same way in males and females given dietary choice. This suggests that the sexes are constrained from feeding to their sex‐specific nutritional optima for these traits. Here, we examine the potential for intralocus sexual conflict (IASC) over optimal protein and carbohydrate intake for LS and reproduction to constrain the evolution of sex‐specific nutrient regulation in the field cricket, Teleogryllus commodus. We show clear sex differences in the effects of protein and carbohydrate intake on LS and reproduction and strong positive genetic correlations between the sexes for the regulated intake of these nutrients. However, the between‐sex additive genetic covariance matrix had very little effect on the predicted evolutionary response of nutrient regulation in the sexes. Thus, IASC appears unlikely to act as an evolutionary constraint on sex‐specific nutrient regulation in T. commodus. This finding is supported by clear sexual dimorphism in the regulated intake of these nutrients under dietary choice. However, nutrient regulation did not coincide with the nutritional optima for LS or reproduction in either sex, suggesting that IASC is not completely resolved in T. commodus. PMID:28640400
Khan, M S; Khan, M S; Hasan, R; Godfrey-Faussett, P
2013-09-01
In developing countries, only one-third of new tuberculosis cases notified are from women. It is not clear whether tuberculosis incidence is lower in women than men, or whether notification figures reflect under-detection of tuberculosis in women. Pakistan, however, presents an unusual pattern of sex differences in tuberculosis notifications. While 2 of the 4 provinces (Sindh and Punjab) report more notifications from men (female to male ratios 0.81 and 0.89 respectively in 2009), the other 2 provinces (Khyber-Pakhtunkhwa and Balochistan) consistently report higher numbers of smear-positive tuberculosis notifications from women than men (1.37 and 1.40). No other country is known to have such a large variation in the sex ratios of notifications across regions. Large variations in female to male smear-positive notification ratios in different settings across a single country may indicate that environmental factors, rather than endogenous biological factors, are important in influencing the observed sex differences in tuberculosis notifications.
Suicide in married couples in Sweden: Is the risk greater in same-sex couples?
Björkenstam, Charlotte; Andersson, Gunnar; Dalman, Christina; Cochran, Susan; Kosidou, Kyriaki
2016-07-01
Minority sexual orientation is a predictor of suicide ideation and attempts, though its association with suicide mortality is less clear. We capitalize on Sweden's extensively linked databases, to investigate whether, among married individuals, same-sex marriage is associated with suicide. Using a population-based register design, we analyzed suicide risk among same-sex married women and men (n = 6456), as compared to different-sex married women and men (n = 1181723) in Sweden. We selected all newly partnered or married individuals in the intervening time between 1/1/1996 and 12/31/2009 and followed them with regard to suicide until 12/31/2011. Multivariate Poisson regression was used to calculate adjusted incidence risk ratios (IRR) with 95 % confidence intervals (CI). The risk of suicide was higher among same-sex married individuals as compared to different-sex married individuals (IRR 2.7, 95 % CI 1.5-4.8), after adjustment for time at risk and socioeconomic confounding. Sex-stratified analyses showed a tentatively elevated risk for same-sex married women (IRR 2.5, 95 % CI 0.8-7.7) as compared to different-sex married women. Among same-sex married men the suicide risk was nearly three-fold greater as compared to different-sex married (IRR 2.895 % CI 1.5-5.5). This holds true also after adjustment for HIV status. Even in a country with a comparatively tolerant climate regarding homosexuality such as Sweden, same-sex married individuals evidence a higher risk for suicide than other married individuals.
Sex, Gender, and Pain: A Review of Recent Clinical and Experimental Findings
Fillingim, Roger B.; King, Christopher D.; Ribeiro-Dasilva, Margarete C.; Rahim-Williams, Bridgett; Riley, Joseph L.
2009-01-01
Sex-related influences on pain and analgesia have become a topic of tremendous scientific and clinical interest, especially in the last 10 to 15 years. Members of our research group published reviews of this literature more than a decade ago, and the intervening time period has witnessed robust growth in research regarding sex, gender, and pain. Therefore, it seems timely to revisit this literature. Abundant evidence from recent epidemiologic studies clearly demonstrates that women are at substantially greater risk for many clinical pain conditions, and there is some suggestion that postoperative and procedural pain may be more severe among women than men. Consistent with our previous reviews, current human findings regarding sex differences in experimental pain indicate greater pain sensitivity among females compared with males for most pain modalities, including more recently implemented clinically relevant pain models such as temporal summation of pain and intramuscular injection of algesic substances. The evidence regarding sex differences in laboratory measures of endogenous pain modulation is mixed, as are findings from studies using functional brain imaging to ascertain sex differences in pain-related cerebral activation. Also inconsistent are findings regarding sex differences in responses to pharmacologic and non-pharmacologic pain treatments. The article concludes with a discussion of potential biopsychosocial mechanisms that may underlie sex differences in pain, and considerations for future research are discussed. Perspective This article reviews the recent literature regarding sex, gender, and pain. The growing body of evidence that has accumulated in the past 10 to 15 years continues to indicate substantial sex differences in clinical and experimental pain responses, and some evidence suggests that pain treatment responses may differ for women versus men. PMID:19411059
Electrolaryngographically derived voice source changes of child and adolescent singers.
Barlow, Christopher; Howard, David M
2005-01-01
Children are the most likely demographic group to undertake regular singing or singing training, but to date there has been little quantitative research into the voice production of children. The authors used closed quotient (CQ) measurements to analyse the singing voices of over 200 male and female, trained and untrained singers aged 8-18 years for differences in voice source according to sex, vocal training and age. Results indicated that the voice source production of subjects could be clearly divided into groups according to age, sex and the level of vocal training received. It was concluded that the process of training a young voice has a quantifiable effect upon the voice source. It was also concluded that sex differences result in significant differences in the voice source of child and adolescent singers.
Charlesworth, Deborah
2018-01-01
Sex chromosomes regularly evolve suppressed recombination, distinguishing them from other chromosomes, and the reason for this has been debated for many years. It is now clear that non-recombining sex-linked regions have arisen in different ways in different organisms. A major hypothesis is that a sex-determining gene arises on a chromosome and that sexually antagonistic (SA) selection (sometimes called intra-locus sexual conflict) acting at a linked gene has led to the evolution of recombination suppression in the region, to reduce the frequency of low fitness recombinant genotypes produced. The sex chromosome system of the guppy (Poecilia reticulata) is often cited as supporting this hypothesis because SA selection has been demonstrated to act on male coloration in natural populations of this fish, and probably contributes to maintaining polymorphisms for the genetic factors involved. I review classical genetic and new molecular genetic results from the guppy, and other fish, including approaches for identifying the genome regions carrying sex-determining loci, and suggest that the guppy may exemplify a recently proposed route to sex chromosome evolution. PMID:29783761
Cross-Cultural Studies of Personality Traits and their Relevance to Psychiatry
Terracciano, Antonio; McCrae, Robert R.
2009-01-01
Aims This article provides a brief review of recent cross-cultural research on personality traits at both individual and culture levels, highlighting the relevance of recent findings for psychiatry. Method In most cultures around the world, personality traits can be clearly summarized by the five broad dimensions of the Five-Factor Model (FFM), which makes it feasible to compare cultures on personality and psychopathology. Results Maturational patterns and sex differences in personality traits generally show cultural invariance, which generates the hypothesis that age of onset, clinical evolution, and sex differences in the prevalence of psychiatric disorders might follow similar universal patterns. The average personality profiles from 51 cultures show meaningful geographical distributions and associations with culture-level variables, but are clearly unrelated to national character stereotypes. Conclusions Aggregate personality scores can potentially be related to epidemiological data on psychiatric disorders, and dimensional personality models have implications for psychiatric diagnosis and treatment around the world. PMID:17128620
Scelo, Ghislaine; Li, Peng; Chanudet, Estelle; Muller, David C
2017-01-31
It is well established that men are at higher risk of most non-sex-specific cancers than women, but there has been surprisingly little research investigating these differences. This is possibly because differences in exposure to established risk factors and hypothesised protection by female sex hormones are thought to account for the totality of the sex differences. These explanations remain somewhat speculative, as the magnitude of the sex ratio in cancer incidence has not been systematically studied, with no quantitative estimate of the variability of the sex ratio across countries, age groups, and periods of diagnosis. We analysed worldwide cancer incidence data for the years 1978-2007 in terms of sex disparities, and explicitly quantified the variability in sex disparities by age, year, and geographical region. Our analysis highlights several cancer types for which suspected and commonly accepted factors are unlikely to fully explain the observed sex disparity. In particular, kidney cancer showed a 2:1 male/female case incidence ratio that was constant by age, year, and region, suggesting that factors other than sociocultural habits and health behaviours are responsible for this sex disparity. We quantified the difference in the incidence of various cancer types between men and women across the world over 30 years. While the trends for some cancers such as lung cancer are clearly correlated with known variations in lifestyle habits, we found that the sex disparity observed for others such as kidney cancer is unlikely to be explained by known risk factors. Copyright © 2017 European Association of Urology. Published by Elsevier B.V. All rights reserved.
Sex in an Evolutionary Perspective: Just Another Reaction Norm
Nylin, Sören
2010-01-01
It is common to refer to all sorts of clear-cut differences between the sexes as something that is biologically almost inevitable. Although this does not reflect the status of evolutionary theory on sex determination and sexual dimorphism, it is probably a common view among evolutionary biologists as well, because of the impact of sexual selection theory. To get away from thinking about biological sex and traits associated with a particular sex as something static, it should be recognized that in an evolutionary perspective sex can be viewed as a reaction norm, with sex attributes being phenotypically plastic. Sex determination itself is fundamentally plastic, even when it is termed “genetic”. The phenotypic expression of traits that are statistically associated with a particular sex always has a plastic component. This plasticity allows for much more variation in the expression of traits according to sex and more overlap between the sexes than is typically acknowledged. Here we review the variation and frequency of evolutionary changes in sex, sex determination and sex roles and conclude that sex in an evolutionary time-frame is extremely variable. We draw on recent findings in sex determination mechanisms, empirical findings of morphology and behaviour as well as genetic and developmental models to explore the concept of sex as a reaction norm. From this point of view, sexual differences are not expected to generally fall into neat, discrete, pre-determined classes. It is important to acknowledge this variability in order to increase objectivity in evolutionary research. PMID:21170116
Coretti, Lorena; Cristiano, Claudia; Florio, Ermanno; Scala, Giovanni; Lama, Adriano; Keller, Simona; Cuomo, Mariella; Russo, Roberto; Pero, Raffaela; Paciello, Orlando; Mattace Raso, Giuseppina; Meli, Rosaria; Cocozza, Sergio; Calignano, Antonio; Chiariotti, Lorenzo; Lembo, Francesca
2017-01-01
Alterations of microbiota-gut-brain axis have been invoked in the pathogenesis of autism spectrum disorders (ASD). Mouse models could represent an excellent tool to understand how gut dysbiosis and related alterations may contribute to autistic phenotype. In this study we paralleled gut microbiota (GM) profiles, behavioral characteristics, intestinal integrity and immunological features of colon tissues in BTBR T + tf/J (BTBR) inbred mice, a well established animal model of ASD. Sex differences, up to date poorly investigated in animal models, were specifically addressed. Results showed that BTBR mice of both sexes presented a marked intestinal dysbiosis, alterations of behavior, gut permeability and immunological state with respect to prosocial C57BL/6j (C57) strain. Noticeably, sex-related differences were clearly detected. We identified Bacteroides, Parabacteroides, Sutterella, Dehalobacterium and Oscillospira genera as key drivers of sex-specific gut microbiota profiles associated with selected pathological traits. Taken together, our findings indicate that alteration of GM in BTBR mice shows relevant sex-associated differences and supports the use of BTBR mouse model to dissect autism associated microbiota-gut-brain axis alteration. PMID:28349974
Students' Attitudes towards Mathematics in Single-Sex and Coeducational Schools.
ERIC Educational Resources Information Center
Norton, Stephen J.; Rennie, Leonie J.
1998-01-01
Discusses part of study stimulated by the continuing debate over differences between boys and girls in their attitudes towards mathematics and their participation and performance in this subject at school. Concludes that there were clear differences between boys and girls on the Mathematics as a Male Domain scale with girls being less stereotyped…
Political Socialization in Israel and the West Bank.
ERIC Educational Resources Information Center
Lawson, E. D.
This paper discusses a survey undertaken to determine how children of different sexes and of different religious/ethnic groups in the Middle East form political attitudes. In this survey, special emphasis was placed on the rate of development of the assumed political attitudes, the age and grade level of the emergence of clear political…
Sex differences in partner preferences in humans and animals.
Balthazart, Jacques
2016-02-19
A large number of morphological, physiological and behavioural traits are differentially expressed by males and females in all vertebrates including humans. These sex differences, sometimes, reflect the different hormonal environment of the adults, but they often remain present after subjects of both sexes are placed in the same endocrine conditions following gonadectomy associated or not with hormonal replacement therapy. They are then the result of combined influences of organizational actions of sex steroids acting early during development, or genetic differences between the sexes, or epigenetic mechanisms differentially affecting males and females. Sexual partner preference is a sexually differentiated behavioural trait that is clearly controlled in animals by the same type of mechanisms. This is also probably true in humans, even if critical experiments that would be needed to obtain scientific proof of this assertion are often impossible for pragmatic or ethical reasons. Clinical, epidemiological and correlative studies provide, however, converging evidence strongly suggesting, if not demonstrating, that endocrine, genetic and epigenetic mechanisms acting during the pre- or perinatal life control human sexual orientation, i.e. homosexuality versus heterosexuality. Whether they interact with postnatal psychosexual influences remains, however, unclear at present. © 2016 The Author(s).
Sex/Gender Differences and Autism: Setting the Scene for Future Research
Lai, Meng-Chuan; Lombardo, Michael V.; Auyeung, Bonnie; Chakrabarti, Bhismadev; Baron-Cohen, Simon
2015-01-01
Objective The relationship between sex/gender differences and autism has attracted a variety of research ranging from clinical and neurobiological to etiological, stimulated by the male bias in autism prevalence. Findings are complex and do not always relate to each other in a straightforward manner. Distinct but interlinked questions on the relationship between sex/gender differences and autism remain underaddressed. To better understand the implications from existing research and to help design future studies, we propose a 4-level conceptual framework to clarify the embedded themes. Method We searched PubMed for publications before September 2014 using search terms “‘sex OR gender OR females’ AND autism.” A total of 1,906 articles were screened for relevance, along with publications identified via additional literature reviews, resulting in 329 articles that were reviewed. Results Level 1, “Nosological and diagnostic challenges,” concerns the question, “How should autism be defined and diagnosed in males and females?” Level 2, “Sex/gender-independent and sex/gender-dependent characteristics,” addresses the question, “What are the similarities and differences between males and females with autism?” Level 3, “General models of etiology: liability and threshold,” asks the question, “How is the liability for developing autism linked to sex/gender?” Level 4, “Specific etiological–developmental mechanisms,” focuses on the question, “What etiological–developmental mechanisms of autism are implicated by sex/gender and/or sexual/gender differentiation?” Conclusions Using this conceptual framework, findings can be more clearly summarized, and the implications of the links between findings from different levels can become clearer. Based on this 4-level framework, we suggest future research directions, methodology, and specific topics in sex/gender differences and autism. PMID:25524786
Knutsen, Heidi; Wiech, Martin; Duinker, Arne; Maage, Amund
2018-03-27
Previously, high concentrations of cadmium have been found in the hepatopancreas of the edible or brown crab (Cancer pagurus) sampled from positions north of about 67° N, compared to regions further south along the Norwegian coast, with no clear understanding why. In order to study a similar organism in the same ecosystem, the present study analyzed 210 shore crabs (Carcinus maenas) from four different locations along the Norwegian coast, two in the North and two in the South. The physiological variables size, sex, molting stage, hepatosomatic index, carapace color, and gonad maturation were registered, in attempt to explain the high inter-individual variation in cadmium levels in hepatopancreas. In contrast to the brown crabs, the shore crabs showed no clear geographical differences in cadmium concentrations. This indicates physiological differences between the two crab species. No clear and consistent correlations were found between cadmium levels and physiological parameters, except for sex, where cadmium concentration in hepatopancreas was twice as high in males compared to females. The cadmium levels also varied with season, with approximately 40 and 60% lower cadmium concentration in April than August for male and female shore crabs, respectively. None of the analyzed cadmium concentrations in muscle meat from claws exceeded EUs food safety limit, and low cadmium levels in soup prepared from shore crabs clearly indicated that this dish is not problematic regarding food safety.
PowerPoint presentation in learning physiology by undergraduates with different learning styles.
Ankad, Roopa B; Shashikala, G V; Herur, Anita; Manjula, R; Chinagudi, Surekharani; Patil, Shailaja
2015-12-01
PowerPoint presentations (PPTs) have become routine in medical colleges because of their flexible and varied presentation capabilities. Research indicates that students prefer PPTs over the chalk-and-talk method, and there is a lot of debate over advantages and disadvantages of PPTs. However, there is no clear evidence that PPTs improve student learning/performance. Furthermore, there are a variety of learning styles with sex differences in classrooms. It is the responsibility of teacher/facilitator and student to be aware of learning style preferences to improve learning. The present study asked the following research question: do PPTs equally affect the learning of students with different learning styles in a mixed sex classroom? After we assessed students' predominant learning style according to the sensory modality that one most prefers to use when learning, a test was conducted before and after a PPT to assess student performance. The results were analyzed using Student's t-test and ANOVA with a Bonferroni post hoc test. A z-test showed no sex differences in preferred learning styles. There was significant increase in posttest performance compared with that of the pretest in all types of learners of both sexes. There was also a nonsignificant relationship among sex, learning style, and performance after the PPT. A PPT is equally effective for students with different learning style preferences and supports mixed sex classrooms. Copyright © 2015 The American Physiological Society.
Sex differences in animal models of psychiatric disorders
Kokras, N; Dalla, C
2014-01-01
Psychiatric disorders are characterized by sex differences in their prevalence, symptomatology and treatment response. Animal models have been widely employed for the investigation of the neurobiology of such disorders and the discovery of new treatments. However, mostly male animals have been used in preclinical pharmacological studies. In this review, we highlight the need for the inclusion of both male and female animals in experimental studies aiming at gender-oriented prevention, diagnosis and treatment of psychiatric disorders. We present behavioural findings on sex differences from animal models of depression, anxiety, post-traumatic stress disorder, substance-related disorders, obsessive–compulsive disorder, schizophrenia, bipolar disorder and autism. Moreover, when available, we include studies conducted across different stages of the oestrous cycle. By inspection of the relevant literature, it is obvious that robust sex differences exist in models of all psychiatric disorders. However, many times results are conflicting, and no clear conclusion regarding the direction of sex differences and the effect of the oestrous cycle is drawn. Moreover, there is a lack of considerable amount of studies using psychiatric drugs in both male and female animals, in order to evaluate the differential response between the two sexes. Notably, while in most cases animal models successfully mimic drug response in both sexes, test parameters and treatment-sensitive behavioural indices are not always the same for male and female rodents. Thus, there is an increasing need to validate animal models for both sexes and use standard procedures across different laboratories. Linked Articles This article is part of a themed section on Animal Models in Psychiatry Research. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-20 PMID:24697577
Sex-related differences in striatal dopaminergic system after traumatic brain injury.
Xu, Xiupeng; Cao, Shengwu; Chao, Honglu; Liu, Yinlong; Ji, Jing
2016-06-01
Several studies have demonstrated alterations in the dopamine (DA) system after traumatic brain injury (TBI). Additionally, the existence of significant sex-related differences in the dopaminergic system has long been recognized. Accordingly, the purpose of the present study was to investigate whether TBI would differentially alter, in female and male mice, the expression and the function of the striatal vesicular monoamine transporter-2 (VMAT-2), an important DA transporter. After controlled cortical impact (CCI) injury, female mice showed significantly lower striatal DA concentrations and K(+)-evoked DA output. By contrast, no significant sex-related differences were observed in the mRNA and protein levels of striatal dopamine transporter (DAT) and VMAT-2 and the methamphetamine (MA)-evoked DA output. These results demonstrated clear sex-related differences in striatal VMAT-2 function in response to TBI and suggested that female mice may be more sensitive to the TBI-induced inhibition of the VMAT-2 function, as indicated by the greater degree of deficits observed when the VMAT-2 DA-storage function was inhibited by TBI. Moreover, the TBI-induced suppression of locomotion was more pronounced than female mice. Such findings highlight the need for sex-specific considerations when examining differences among brain injury conditions. Copyright © 2016 Elsevier Inc. All rights reserved.
Sex and boldness explain individual differences in spatial learning in a lizard.
Carazo, Pau; Noble, Daniel W A; Chandrasoma, Dani; Whiting, Martin J
2014-05-07
Understanding individual differences in cognitive performance is a major challenge to animal behaviour and cognition studies. We used the Eastern water skink (Eulamprus quoyii) to examine associations between exploration, boldness and individual variability in spatial learning, a dimension of lizard cognition with important bearing on fitness. We show that males perform better than females in a biologically relevant spatial learning task. This is the first evidence for sex differences in learning in a reptile, and we argue that it is probably owing to sex-specific selective pressures that may be widespread in lizards. Across the sexes, we found a clear association between boldness after a simulated predatory attack and the probability of learning the spatial task. In contrast to previous studies, we found a nonlinear association between boldness and learning: both 'bold' and 'shy' behavioural types were more successful learners than intermediate males. Our results do not fit with recent predictions suggesting that individual differences in learning may be linked with behavioural types via high-low-risk/reward trade-offs. We suggest the possibility that differences in spatial cognitive performance may arise in lizards as a consequence of the distinct environmental variability and complexity experienced by individuals as a result of their sex and social tactics.
Segarra, Ignacio; Modamio, Pilar; Fernández, Cecilia; Mariño, Eduardo L
2017-01-01
The efforts toward individualized medicine have constantly increased in an attempt to improve treatment options. These efforts have led to the development of small molecules which target specific molecular pathways involved in cancer progression. We have reviewed preclinical studies of sunitinib that incorporate sex as a covariate to explore possible sex-based differences in pharmacokinetics and drug-drug interactions (DDI) to attempt a relationship with published clinical outputs. We observed that covariate sex is lacking in most clinical outcome reports and suggest a series of ethic-based proposals to improve research activities and identify relevant different sex outcomes. We propose a deeper integration of preclinical, clinical, and translational research addressing statistical and clinical significance jointly; to embed specific sex-divergent endpoints to evaluate possible gender differences objectively during all stages of research; to pay greater attention to sex-divergent outcomes in polypharmacy scenarios, DDI and bioequivalence studies; the clear reporting of preclinical and clinical findings regarding sex-divergent outcomes; as well as to encourage the active role of scientists and the pharmaceutical industry to foster a new scientific culture through their research programs, practice, and participation in editorial boards and Institutional Ethics Review Boards (IRBs) and Research Ethics Committees (RECs). We establish the IRB/REC as the centerpiece for the implementation of these proposals. We suggest the expansion of its competence to follow up clinical trials to ensure that sex differences are addressed and recognized; to engage in data monitoring committees to improve clinical research cooperation and ethically address those potential clinical outcome differences between male and female patients to analyze their social and clinical implications in research and healthcare policies.
Segarra, Ignacio; Modamio, Pilar; Fernández, Cecilia; Mariño, Eduardo L.
2017-01-01
The efforts toward individualized medicine have constantly increased in an attempt to improve treatment options. These efforts have led to the development of small molecules which target specific molecular pathways involved in cancer progression. We have reviewed preclinical studies of sunitinib that incorporate sex as a covariate to explore possible sex-based differences in pharmacokinetics and drug–drug interactions (DDI) to attempt a relationship with published clinical outputs. We observed that covariate sex is lacking in most clinical outcome reports and suggest a series of ethic-based proposals to improve research activities and identify relevant different sex outcomes. We propose a deeper integration of preclinical, clinical, and translational research addressing statistical and clinical significance jointly; to embed specific sex-divergent endpoints to evaluate possible gender differences objectively during all stages of research; to pay greater attention to sex-divergent outcomes in polypharmacy scenarios, DDI and bioequivalence studies; the clear reporting of preclinical and clinical findings regarding sex-divergent outcomes; as well as to encourage the active role of scientists and the pharmaceutical industry to foster a new scientific culture through their research programs, practice, and participation in editorial boards and Institutional Ethics Review Boards (IRBs) and Research Ethics Committees (RECs). We establish the IRB/REC as the centerpiece for the implementation of these proposals. We suggest the expansion of its competence to follow up clinical trials to ensure that sex differences are addressed and recognized; to engage in data monitoring committees to improve clinical research cooperation and ethically address those potential clinical outcome differences between male and female patients to analyze their social and clinical implications in research and healthcare policies. PMID:28785221
Women, Men and Personal Sales: An Analysis of Sex Differences in Compliance Gaining Strategy Use.
ERIC Educational Resources Information Center
Sprowl, John
A study explored the effects of both the sales representative's and the target consumer's biological gender upon the persuasive strategy choice of the salesperson. Data from 204 salespeople responding to a 27-item questionnaire were collected over a 6-week period. The results indicate clear differences between men and women sales representatives…
Shape, size, and maturity trajectories of the human ilium.
Wilson, Laura A B; Ives, Rachel; Cardoso, Hugo F V; Humphrey, Louise T
2015-01-01
Morphological traits of the ilium have consistently been more successful for juvenile sex determination than have techniques applied to other skeletal elements, however relatively little is known about the ontogeny and maturation of size and shape dimorphism in the ilium. We use a geometric morphometric approach to quantitatively separate the ontogeny of size and shape of the ilium, and analyze interpopulation differences in the onset, rate and patterning of sexual dimorphism. We captured the shape of three traits for a total of 191 ilia from Lisbon (Portugal) and London (UK) samples of known age and sex (0-17 years). Our results indicate that a) there is a clear dissociation between the ontogeny of size and shape in males and females, b) the ontogeny of size and shape are each defined by non-linear trajectories that differ between the sexes, c) there are interpopulation differences in ontogenetic shape trajectories, which point to population-specific patterning in the attainment of sexual dimorphism, and d) the rate of shape maturation and size maturation is typically higher for females than males. Male and female shape differences in the ilium are brought about by trajectory divergence. Differences in size and shape maturation between the sexes suggest that maturity may confound our ability to discriminate between the sexes by introducing variation not accounted for in age-based groupings. The accuracy of sex determination methods using the ilium may be improved by the use of different traits for particular age groups, to capture the ontogenetic development of shape in both sexes. © 2014 Wiley Periodicals, Inc.
Happiness and Sexual Minority Status
Thomeer, Mieke Beth; Reczek, Corinne
2017-01-01
We used logistic regression on nationally representative data (General Social Survey, N = 10,668 and N = 6,680) to examine how sexual minority status related to happiness. We considered two central dimensions of sexual minority status—sexual behavior and sexual identity. We distinguished between same-sex, both-sex, and different-sex oriented participants. Because individuals transition between sexual behavior categories over the life course (e.g., from both-sex partners to only same-sex partners) and changes in sexual minority status have theoretical associations with well-being, we also tested the effects of transitions on happiness. Results showed that identifying as bisexual, gay, or lesbian, having both male and female partners since age 18, or transitioning to only different-sex partners was negatively related to happiness. Those with only same-sex partners since age 18 or in the past five years had similar levels of happiness as those with only different-sex partners since age 18. Additional tests showed that the majority of these happiness differences became non-significant when economic and social resources were included, indicating that the lower happiness was a product of structural and societal forces. Our findings clearly and robustly underscored the importance of taking a multi-faceted approach to understanding sexuality and well-being, demonstrating that not all sexual minority groups experience disadvantaged happiness. Our study calls for more attention to positive aspects of well-being such as happiness in examinations of sexual minorities and suggests that positive psychology and other happiness subfields should consider the role of sexual minority status in shaping happiness. PMID:27102605
Happiness and Sexual Minority Status.
Thomeer, Mieke Beth; Reczek, Corinne
2016-10-01
We used logistic regression on nationally representative data (General Social Survey, N = 10,668 and N = 6680) to examine how sexual minority status related to happiness. We considered two central dimensions of sexual minority status-sexual behavior and sexual identity. We distinguished between same-sex, both-sex, and different-sex-oriented participants. Because individuals transition between sexual behavior categories over the life course (e.g., from both-sex partners to only same-sex partners) and changes in sexual minority status have theoretical associations with well-being, we also tested the associations of transitions with happiness. Results showed that identifying as bisexual, gay, or lesbian, having both male and female partners since age 18, or transitioning to only different-sex partners was negatively related to happiness. Those with only same-sex partners since age 18 or in the past 5 years had similar levels of happiness as those with only different-sex partners since age 18. Additional tests showed that the majority of these happiness differences became non-significant when economic and social resources were included, indicating that the lower happiness was a product of structural and societal forces. Our findings clearly and robustly underscored the importance of taking a multi-faceted approach to understanding sexuality and well-being, demonstrating that not all sexual minority groups experience disadvantaged happiness. Our study calls for more attention to positive aspects of well-being such as happiness in examinations of sexual minorities and suggests that positive psychology and other happiness subfields should consider the role of sexual minority status in shaping happiness.
Students' attitudes towards mathematics in single-sex and coeducational schools
NASA Astrophysics Data System (ADS)
Norton, Stephen J.; Rennie, Léonie J.
1998-04-01
This paper examines students' attitudes towards mathematics at the secondary school level. Using five of the Fennema-Sherman scales, the attitudes of boys and girls in Grades 8 to 12 in four schools were compared: a single-sex boys' and a single-sex girls' private school, and a state and a private coeducational school. Multivariate analysis of variance was used to guide an exploration of how students' attitudes varied according to grade, sex and educational setting. There were no differences between students in the two coeducational schools. In general, students' attitudes were found to be less positive in more senior grades; and overall, boys had more positive attitudes than girls. There were clear differences between boys and girls on the Mathematics as a Male Domain scale, with girls being less stereotyped in their perceptions than boys. Except for this scale, effects related to the sex of the student were small, and effects relating to grade level and school type on all variables were also small. Implications are drawn for future research in this area.
Balancing Selection in Species with Separate Sexes: Insights from Fisher’s Geometric Model
Connallon, Tim; Clark, Andrew G.
2014-01-01
How common is balancing selection, and what fraction of phenotypic variance is attributable to balanced polymorphisms? Despite decades of research, answers to these questions remain elusive. Moreover, there is no clear theoretical prediction about the frequency with which balancing selection is expected to arise within a population. Here, we use an extension of Fisher’s geometric model of adaptation to predict the probability of balancing selection in a population with separate sexes, wherein polymorphism is potentially maintained by two forms of balancing selection: (1) heterozygote advantage, where heterozygous individuals at a locus have higher fitness than homozygous individuals, and (2) sexually antagonistic selection (a.k.a. intralocus sexual conflict), where the fitness of each sex is maximized by different genotypes at a locus. We show that balancing selection is common under biologically plausible conditions and that sex differences in selection or sex-by-genotype effects of mutations can each increase opportunities for balancing selection. Although heterozygote advantage and sexual antagonism represent alternative mechanisms for maintaining polymorphism, they mutually exist along a balancing selection continuum that depends on population and sex-specific parameters of selection and mutation. Sexual antagonism is the dominant mode of balancing selection across most of this continuum. PMID:24812306
Onishi, Makiko; Yamanaka, Ko; Miyamoto, Yasunori; Waki, Hidefumi; Gouraud, Sabine
2018-04-01
Arterial pressure (AP) is lower in premenopausal women than in men of a similar age. Premenopausal women exhibit a lower sympathetic activity and a greater baroreceptor reflex; however, mechanisms controlling sex differences in blood pressure regulation are not well understood. We hypothesized that different neuronal functions in the cardiovascular centers of the brains of men and women may contribute to the sex difference in cardiovascular homeostasis. Our previous studies on male spontaneously hypertensive rats (SHRs) and their normotensive counterparts, Wistar Kyoto (WKY) rats, revealed that the gene-expression profile of the nucleus tractus solitarius (NTS), a region of the medulla oblongata that is pivotal for regulating the set point of AP, is strongly associated with AP. Thus, we hypothesized that gene-expression profiles in the rat NTS are related to sex differences in AP regulation. Because female SHRs clearly exhibit lower AP than their male counterparts of a similar age, we investigated whether SHR NTS exhibits sex differences in gene expression by using microarray and RT-qPCR experiments. The transcript for transient receptor potential cation channel subfamily V member 4 ( Trpv4) was found to be upregulated in SHR NTS in females compared with that in males. The channel was expressed in neurons and glial cells within NTS. The TRPV4 agonist 4-alpha-phorbol-12,13-didecanoate (4α-PDD) decreased blood pressure when injected into NTS of rats. These findings suggest that altered TRPV4 expression might be involved in the sex differences in blood pressure regulation.
Sex differences in gingivitis relate to interaction of oral health behaviors in young people.
Furuta, Michiko; Ekuni, Daisuke; Irie, Koichiro; Azuma, Tetsuji; Tomofuji, Takaaki; Ogura, Toshio; Morita, Manabu
2011-04-01
Although many epidemiologic surveys have shown that gingivitis is more prevalent in males than in females, few studies have clearly explained what causes this difference. The objective of the present study is to explain the sex difference in gingivitis based on the interaction between oral health behaviors and related factors, such as knowledge, attitude, and lifestyle, in young people. The study was comprised of 838 subjects (440 males and 398 females), aged 18 and 19 years. Gingivitis was assessed by the percentage of bleeding on probing (%BOP). Additional information was collected regarding oral hygiene status, oral health behaviors, and related factors. Structural equation modeling was used to test pathways from these factors to %BOP. Multiple-group modeling was also conducted to test for sex differences. Females had greater knowledge, a more positive attitude, a healthier lifestyle, and higher level of oral health behaviors than males. There were significant differences in the paths (i.e., from lifestyle, knowledge, and attitude to %BOP) through oral health behaviors and oral health status. Sex-based differences in gingivitis in young people can be explained by oral health behaviors and hygiene status, which are influenced by lifestyle, knowledge, and attitude. To prevent gingivitis, different approaches to males and females may be useful.
Sex differences in physiological reactivity to acute psychosocial stress in adolescence.
Ordaz, Sarah; Luna, Beatriz
2012-08-01
Females begin to demonstrate greater negative affective responses to stress than males in adolescence. This may reflect the concurrent emergence of underlying differences in physiological response systems, including corticolimbic circuitries, the hypothalamic-pituitary-adrenal axis (HPAA), and the autonomic nervous system (ANS). This review examines when sex differences in physiological reactivity to acute psychosocial stress emerge and the directionality of these differences over development. Indeed, the literature indicates that sex differences emerge during adolescence and persist into adulthood for all three physiological response systems. However, the directionality of the differences varies by system. The emerging corticolimbic reactivity literature suggests greater female reactivity, particularly in limbic regions densely innervated by gonadal hormone receptors. In contrast, males generally show higher levels of HPAA and ANS reactivity. We argue that the contrasting directionality of corticolimbic and peripheral physiological responses may reflect specific effects of gonadal hormones on distinct systems and also sex differences in evolved behavioral responses that demand different levels of peripheral physiological activation. Studies that examine both subjective reports of negative affect and physiological responses indicate that beginning in adolescence, females respond to acute stressors with more intense negative affect than males despite their comparatively lower peripheral physiological responses. This dissociation is not clearly explained by sex differences in the strength of the relationship between physiological and subjective responses. We suggest that females' greater subjective responsivity may instead arise from a greater activity in brain regions that translate stress responses to subjective awareness in adolescence. Future research directions include investigations of the role of pubertal hormones in physiological reactivity across all systems, examining the relationship of corticolimbic reactivity and negative affect, and sex differences in emotion regulation processes. Copyright © 2012 Elsevier Ltd. All rights reserved.
Sex differences in physiological reactivity to acute psychosocial stress in adolescence
Ordaz, Sarah; Luna, Beatriz
2012-01-01
Summary Females begin to demonstrate greater negative affective responses to stress than males in adolescence. This may reflect the concurrent emergence of underlying differences in physiological response systems, including corticolimbic circuitries, the hypothalamic—pituitary— adrenal axis (HPAA), and the autonomic nervous system (ANS). This review examines when sex differences in physiological reactivity to acute psychosocial stress emerge and the directionality of these differences over development. Indeed, the literature indicates that sex differences emerge during adolescence and persist into adulthood for all three physiological response systems. However, the directionality of the differences varies by system. The emerging corti-colimbic reactivity literature suggests greater female reactivity, particularly in limbic regions densely innervated by gonadal hormone receptors. In contrast, males generally show higher levels of HPAA and ANS reactivity. We argue that the contrasting directionality of corticolimbic and peripheral physiological responses may reflect specific effects of gonadal hormones on distinct systems and also sex differences in evolved behavioral responses that demand different levels of peripheral physiological activation. Studies that examine both subjective reports of negative affect and physiological responses indicate that beginning in adolescence, females respond to acute stressors with more intense negative affect than males despite their comparatively lower peripheral physiological responses. This dissociation is not clearly explained by sex differences in the strength of the relationship between physiological and subjective responses. We suggest that females' greater subjective responsivity may instead arise from a greater activity in brain regions that translate stress responses to subjective awareness in adolescence. Future research directions include investigations of the role of pubertal hormones in physiological reactivity across all systems, examining the relationship of corticolimbic reactivity and negative affect, and sex differences in emotion regulation processes. PMID:22281210
Detecting depression among adolescents in Santiago, Chile: sex differences.
Araya, Ricardo; Montero-Marin, Jesus; Barroilhet, Sergio; Fritsch, Rosemarie; Gaete, Jorge; Montgomery, Alan
2013-04-23
Depression among adolescents is common but most cases go undetected. Brief questionnaires offer an opportunity to identify probable cases but properly validated cut-off points are often unavailable, especially in non-western countries. Sex differences in the prevalence of depression become marked in adolescence and this needs to be accounted when establishing cut-off points. This study involved adolescents attending secondary state schools in Santiago, Chile. We compared the self-reported Beck Depression Inventory-II with a psychiatric interview to ascertain diagnosis. General psychometric features were estimated before establishing the criterion validity of the BDI-II. The BDI-II showed good psychometric properties with good internal consistency, a clear unidimensional factorial structure, and good capacity to discriminate between cases and non-cases of depression. Optimal cut-off points to establish caseness for depression were much higher for girls than boys. Sex discrepancies were primarily explained by differences in scores among those with depression rather than among those without depression. It is essential to validate scales with the populations intended to be used with. Sex differences are often ignored when applying cut-off points, leading to substantial misclassification. Early detection of depression is essential if we think that early intervention is a clinically important goal.
Otoacoustic emissions measured in rhesus monkeys (Macaca mulatta)
NASA Astrophysics Data System (ADS)
McFadden, Dennis; Pasanen, Edward G.; Raper, Jessica; Wallen, Kim
2003-10-01
In humans, otoacoustic emissions (OAEs) are stronger in females than in males and stronger in right ears than in left. The physiological bases for these differences are unknown, but several lines of circumstantial evidence suggest that the sex difference is attributable to androgenizing mechanisms operating during prenatal development. Specifically, it appears that exposure to high levels of androgens during prenatal development diminishes the strength of the cochlear amplifiers and thus the strength of the OAEs. Sex and ear differences in OAEs have not been well studied in species other than humans. Accordingly, click-evoked OAEs and distortion-product OAEs were measured in nine female and nine male rhesus monkeys. For CEOAEs, but less clearly for DPOAEs, females exhibited significantly stronger OAEs than males. There was no consistent ear difference for either sex for either type of OAE. In order to better study the early components of the CEOAE waveform, a nonlinear procedure [Molenaar et al., Hearing Res. 143, 197-207 (2002)] was used to collect CEOAEs along with our standard (linear) procedure. This colony also contains animals of each sex that were treated with androgenic or antiandrogenic agents during prenatal development, and OAEs are also currently being measured on those animals. [Work supported by NIDCD.
Torimitsu, Suguru; Makino, Yohsuke; Saitoh, Hisako; Sakuma, Ayaka; Ishii, Namiko; Yajima, Daisuke; Inokuchi, Go; Motomura, Ayumi; Chiba, Fumiko; Yamaguchi, Rutsuko; Hashimoto, Mari; Hoshioka, Yumi; Iwase, Hirotaro
2015-12-01
Sex estimation of decomposed or skeletal remains is clearly important in forensic contexts. Recently, contemporary population-specific data has been obtained using multidetector computed tomography (MDCT) scanning. The main purpose of this study was to investigate skeletal pelvic dimorphism in a contemporary Japanese forensic sample and to quantify the accuracy of sex estimation using various pelvic measurements obtained from three-dimensional (3D) CT images. This study used a total of 208 cadavers (104 males, 104 females) of which postmortem CT scanning and subsequent forensic autopsy were conducted between December 2011 and August 2014. Eleven measurements of each pelvis were obtained from 3D CT reconstructed images that extracted only bone data. The measurements were analyzed using descriptive statistics and discriminant function analyses. All except one measurement were dimorphic in terms of sex differences. Univariate discriminant function analyses using these measurements provided sex classification accuracy rates of 62.0-98.1%. The subpubic angle was found to contribute most significantly to accurate sex estimation. Multivariate discriminant functions yielded sex prediction accuracy rates of 63.9-98.1%. In conclusion, the pelvic measurements obtained from 3D CT images of a contemporary Japanese population successfully demonstrated sexual dimorphism and may be useful for the estimation of skeletal sex in the field of forensic anthropology. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Sex and strain dependent differences in mucosal immunology and microbiota composition in mice.
Elderman, Marlies; Hugenholtz, Floor; Belzer, Clara; Boekschoten, Mark; van Beek, Adriaan; de Haan, Bart; Savelkoul, Huub; de Vos, Paul; Faas, Marijke
2018-06-18
A dysbiosis in the intestinal microbiome plays a role in the pathogenesis of several immunological diseases. These diseases often show a sex bias, suggesting sex differences in immune responses and in the intestinal microbiome. We hypothesized that sex differences in immune responses are associated with sex differences in microbiota composition. Fecal microbiota composition (MITchip), mRNA expression in intestinal tissue (microarray), and immune cell populations in mesenteric lymph nodes (MLNs) were studied in male and female mice of two mouse strains (C57B1/6OlaHsd and Balb/cOlaHsd). Transcriptomics and microbiota data were combined to identify bacterial species which may potentially be related to sex-specific differences in intestinal immune related genes. We found clear sex differences in intestinal microbiota species, diversity, and richness in healthy mice. However, the nature of the sex effects appeared to be determined by the mouse strain as different bacterial species were enriched in males and females of the two strains. For example, Lactobacillus plantarum and Bacteroides distasonis were enriched in B6 females as compared to B6 males, while Bifidobacterium was enriched BALB/c females as compared to BALB/c males. The strain-dependent sex effects were also observed in the expression of immunological genes in the colon. We found that the abundance of various bacteria (e.g., Clostridium leptum et rel.) which were enriched in B6 females positively correlated with the expression of several genes (e.g., Il-2rb, Ccr3, and Cd80) which could be related to immunological functions, such as inflammatory responses and migration of leukocytes. The abundance of several bacteria (e.g., Faecalibacterium prausnitzii et rel. and Coprobacillus et rel.- Clostridium ramosum et rel.) which were enriched in BALB/c males positively correlated to the expression of several genes (e.g., Apoe, Il-1b, and Stat4) related to several immunological functions, such as proliferation and quantity of lymphocytes. The net result was the same, since both mouse strains showed similar sex induced differences in immune cell populations in the MLNs. Our data suggests a correlation between microbiota and intestinal immune populations in a sex and strain-specific way. These findings may contribute to the development of more sex and genetic specific treatments for intestinal-related disorders.
Male-to-female transsexuals have female neuron numbers in a limbic nucleus.
Kruijver, F P; Zhou, J N; Pool, C W; Hofman, M A; Gooren, L J; Swaab, D F
2000-05-01
Transsexuals experience themselves as being of the opposite sex, despite having the biological characteristics of one sex. A crucial question resulting from a previous brain study in male-to-female transsexuals was whether the reported difference according to gender identity in the central part of the bed nucleus of the stria terminalis (BSTc) was based on a neuronal difference in the BSTc itself or just a reflection of a difference in vasoactive intestinal polypeptide innervation from the amygdala, which was used as a marker. Therefore, we determined in 42 subjects the number of somatostatin-expressing neurons in the BSTc in relation to sex, sexual orientation, gender identity, and past or present hormonal status. Regardless of sexual orientation, men had almost twice as many somatostatin neurons as women (P < 0.006). The number of neurons in the BSTc of male-to-female transsexuals was similar to that of the females (P = 0.83). In contrast, the neuron number of a female-to-male transsexual was found to be in the male range. Hormone treatment or sex hormone level variations in adulthood did not seem to have influenced BSTc neuron numbers. The present findings of somatostatin neuronal sex differences in the BSTc and its sex reversal in the transsexual brain clearly support the paradigm that in transsexuals sexual differentiation of the brain and genitals may go into opposite directions and point to a neurobiological basis of gender identity disorder.
Brelsford, Alan; Perrin, Nicolas
2014-01-01
In contrast with mammals and birds, most poikilothermic vertebrates feature structurally undifferentiated sex chromosomes, which may result either from frequent turnovers, or from occasional events of XY recombination. The latter mechanism was recently suggested to be responsible for sex-chromosome homomorphy in European tree frogs (Hyla arborea). However, no single case of male recombination has been identified in large-scale laboratory crosses, and populations from NW Europe consistently display sex-specific allelic frequencies with male-diagnostic alleles, suggesting the absence of recombination in their recent history. To address this apparent paradox, we extended the phylogeographic scope of investigations, by analyzing the sequences of three sex-linked markers throughout the whole species distribution. Refugial populations (southern Balkans and Adriatic coast) show a mix of X and Y alleles in haplotypic networks, and no more within-individual pairwise nucleotide differences in males than in females, testifying to recurrent XY recombination. In contrast, populations of NW Europe, which originated from a recent postglacial expansion, show a clear pattern of XY differentiation; the X and Y gametologs of the sex-linked gene Med15 present different alleles, likely fixed by drift on the front wave of expansions, and kept differentiated since. Our results support the view that sex-chromosome homomorphy in H. arborea is maintained by occasional or historical events of recombination; whether the frequency of these events indeed differs between populations remains to be clarified. PMID:24892652
Sex Differences: A Resultant of an Evolutionary Pressure?
Della Torre, Sara; Maggi, Adriana
2017-03-07
Spurred by current research policy, we are witnessing a significant growth in the number of studies that observe and describe sexual diversities in human physiology and sex prevalence in a large number of pathologies. Yet we are far from the comprehension of the mechanisms underpinning these differences, which are the result of a long evolutionary history. This Essay is meant to underline female reproductive function as a driver for the positive selection of the specific physiological features that explain male and female differential susceptibility to diseases and metabolic disturbances, in particular. A clear understanding of the causes underlying sexual dimorphisms in the physio-pathology is crucial for precision medicine. Copyright © 2017 Elsevier Inc. All rights reserved.
Serotonin and female psychopathology.
Hall, Elise; Steiner, Meir
2013-01-01
There are sex differences in the prevalence and presentation of many psychiatric disorders. Various trends in symptomatology have emerged that are thought to be linked to periods of hormonal fluctuations such as with menses, pregnancy or menopause. With data from animal and human studies, it has become clear that there is an important interplay between the serotonergic system and gonadal hormones. The majority of the research to date has focused on the influence that estrogen has within the CNS and, in particular, how it leads to an overall increase in serotonin synthesis and availability. In reviewing this female-specific topic we hope to raise awareness to sex/gender differences in psychopathology, help identify at-risk populations and consider development of new treatment options. Future research will also need to consider the influence that progesterone and oxytocin may have on sex-specific psychopathology as well as incorporate neuroimaging and consider the influence of hormones on the serotonergic system at a genetic level.
Interventions that affect gender bias in hiring: a systematic review.
Isaac, Carol; Lee, Barbara; Carnes, Molly
2009-10-01
To systematically review experimental evidence for interventions mitigating gender bias in employment. Unconscious endorsement of gender stereotypes can undermine academic medicine's commitment to gender equity. The authors performed electronic and hand searches for randomized controlled studies since 1973 of interventions that affect gender differences in evaluation of job applicants. Twenty-seven studies met all inclusion criteria. Interventions fell into three categories: application information, applicant features, and rating conditions. The studies identified gender bias as the difference in ratings or perceptions of men and women with identical qualifications. Studies reaffirmed negative bias against women being evaluated for positions traditionally or predominantly held by men (male sex-typed jobs). The assessments of male and female raters rarely differed. Interventions that provided raters with clear evidence of job-relevant competencies were effective. However, clearly competent women were rated lower than equivalent men for male sex-typed jobs unless evidence of communal qualities was also provided. A commitment to the value of credentials before review of applicants and women's presence at above 25% of the applicant pool eliminated bias against women. Two studies found unconscious resistance to "antibias" training, which could be overcome with distraction or an intervening task. Explicit employment equity policies and an attractive appearance benefited men more than women, whereas repeated employment gaps were more detrimental to men. Masculine-scented perfume favored the hiring of both sexes. Negative bias occurred against women who expressed anger or who were perceived as self-promoting. High-level evidence exists for strategies to mitigate gender bias in hiring.
Sex- and age-related variations of the somatotype in a Chuvasha population.
Kalichman, L; Kobyliansky, E
2006-01-01
The aim of this large, cross-sectional study was to describe the age- and sex-related variations of the somatotype, employing Heath and Carter's method, in a Chuvasha population residing in a rural region in central Russia. The investigated sample included 802 males aged 18-89 years (mean 46.9) and 738 females aged 18-90 years (mean 48.6). We evaluated the age and sex differences by one-way ANOVA with somatotype components as dependent variables and sex or age groups as grouping variables. Sex differences of somatotypes appear to be the strongest for endomorphy, with generally higher values in women. Endomorphy in males remained virtually unchanged after 30 years of age, but endomorphy in females kept increasing up to the 6th decade, and then subsequently decreased. Virtually no differences were noted in mesomorphy and a very small difference in ectomorphy between males and females aged 18-30 years. A reduction of sexual dimorphism in all somatotype components after age 70 was also observed. The largest difference of all somatotype components appeared between age groups 18-30 and 31-40 years. Thereafter, somatotypes remained practically unchanged. Mesomorphy continued to increase until the 5th decade in both sexes, while in females, endomorphy continuously increased until their 6th decade. In the 7th and 8th decades, a decrease in mean values was observed. Mesomorphy and ectomorphy showed opposite age-related trends. Results of our study clearly suggest that in physique investigations, the somatotypes need to be studied in each sex separately, and in studies of young people, they need also to be adjusted to age.
Sex ratios in fetuses and liveborn infants with autosomal aneuploidy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heuther, C.A.; Martin, R.L.M.; Stoppelman, S.M.
1996-06-14
Ten data sources were used substantially to increase the available data for estimating fetal and livebirth sex ratios for Patau (trisomy 13), Edwards (trisomy 18), and Down (trisomy 21) syndromes and controls. The fetal sex ratio estimate was 0.88 (N = 584) for trisomy 13, 0.90 (N = 1702) for trisomy 18, and 1.16 (N = 3154) for trisomy 21. All were significantly different from prenatal controls (1.07). The estimated ratios in prenatal controls were 1.28 (N = 1409) for CVSs and 1.06 (N = 49427) for amniocenteses, indicating a clear differential selection against males, mostly during the first halfmore » of fetal development. By contrast, there were no sex ratio differences for any of the trisomies when comparing gestational ages <16 and >16 weeks. The livebirth sex ratio estimate was 0.90 (N = 293) for trisomy 13, 0.63 (N = 497) for trisomy 18, and 1.15 (N = 6424) for trisomy 21, the latter two being statistically different than controls (1.05) (N = 3660707). These ratios for trisomies 13 and 18 were also statistically different than the ratio for trisomy 21. Only in trisomy 18 did the sex ratios in fetuses and livebirths differ, indicating a prenatal selection against males >16 weeks. No effects of maternal age or race were found on these estimates for any of the fetal or livebirth trisomies. Sex ratios for translocations and mosaics were also estimated for these aneuploids. Compared to previous estimates, these results are less extreme, most likely because of larger sample sizes and less sample bias. They support the hypothesis that these trisomy sex ratios are skewed at conception, or become so during embryonic development through differential intrauterine selection. The estimate for Down syndrome livebirths is also consistent with the hypothesis that its higher sex ratio is associated with paternal nondisjunction. 36 refs., 5 tabs.« less
Gender differences in inflammatory markers in children.
Casimir, Georges J A; Mulier, Sandra; Hanssens, Laurence; Zylberberg, Kathya; Duchateau, Jean
2010-03-01
No clear explanation exists to understand how sex hormones and/or chromosomes affect the immune system. In vitro studies of human lymphoid cells also show sex differences in immune function. To evaluate these differences in frequent pediatric emergencies, we analyze the expression of inflammatory markers (C-reactive protein, erythrocyte sedimentation rate, and neutrophil count) underlying inflammatory processes in children: 482 children (241 girls and 241 boys) hospitalized for pneumonia (n = 384), pyelonephritis (n = 39), or bronchiolitis (n = 59) matched for age and sex. All patients were younger than 10 years. A control population of 97 children (50 girls and 47 boys) admitted for day surgery (tonsillectomy, circumcision, or strabismus) was included. We observed highly significant differences between girls and boys: median C-reactive protein concentration of 5.45 mg/dL (range, 0.2-36.0 mg/dL) for girls and 2.6 mg/dL (range, 0.3-37.3 mg/dL) for boys (P < 0.0001), and median erythrocyte sedimentation rate of 39.5 mm/h (range, 2-104 mm/h) for girls and 24 mm/h (range, 4-140 mm/h) for boys (P < 0.005). Neutrophil counts were also significantly different: a median of 8,796 cells/microL (range, 328-27,645 cells/microL) for girls and 6,774 cells/microL (range, 600-38,668 cells/microL) for boys (P < 0.02). The duration of fever after initiating antibiotic therapy was longer in girls than in boys, but there was no difference (Fisher exact test, P < 0.06). The present study documents a relationship between sex and both the production of inflammatory markers and neutrophil recruitment. Sex difference also showed more direct clinical relevance with associations seen between sex and both duration of fever and duration of disease (bronchiolitis P < 0.0007).
Psychological Type and Sex Differences among Church Leaders in the United Kingdom
ERIC Educational Resources Information Center
Craig, Charlotte L.; Francis, Leslie J.; Robbins, Mandy
2004-01-01
A sample of 135 female and 164 male church leaders of mixed denominations completed the Francis Psychological Type Scales. The female church leaders demonstrated clear preferences for extraversion over introversion, for sensing over intuition, for feeling over thinking, and for judging over perceiving. The male church leaders demonstrated clear…
Karyotype and sex chromosome differentiation in two Nalassus species (Coleoptera, Tenebrionidae)
Şendoğan, Dirim; Alpagut-Keskin, Nurşen
2016-01-01
Abstract Cytogenetic features of Nalassus bozdagus Nabozhenko & Keskin, 2010 and Nalassus plebejus Küster, 1850 were analysed using conventional and differential staining. Mitotic and meiotic chromosomal analysis revealed the diploid number as 2n = 20 (9+Xyp) in both species. Besides the general resemblance of two Nalassus Mulsant, 1854 karyotypes, important differences related to variations in the number of metacentric/submetacentric chromosomes, localization of highly impregnated regions which are considered as NOR and heterochromatin distribution are clearly observed. The most prominent difference between two species is found related to the X chromosome which is clearly larger in Nalassus bozdagus and has a conspicuous secondary constriction on the long arm. As a result of silver staining, the existence of highly impregnated areas associated with Xyp of Nalassus bozdagus in both prophase I and metaphase I, suggests that NORs are seemingly located on sex chromosomes. On the other hand, the potential NORs of Nalassus plebejus were observed only in prophase I nuclei. With the application of fluorescence dye DAPI, the AT rich chromosome regions and Xyp which forms the parachute configuration were shown in both species. PMID:27830047
Balancing selection in species with separate sexes: insights from Fisher's geometric model.
Connallon, Tim; Clark, Andrew G
2014-07-01
How common is balancing selection, and what fraction of phenotypic variance is attributable to balanced polymorphisms? Despite decades of research, answers to these questions remain elusive. Moreover, there is no clear theoretical prediction about the frequency with which balancing selection is expected to arise within a population. Here, we use an extension of Fisher's geometric model of adaptation to predict the probability of balancing selection in a population with separate sexes, wherein polymorphism is potentially maintained by two forms of balancing selection: (1) heterozygote advantage, where heterozygous individuals at a locus have higher fitness than homozygous individuals, and (2) sexually antagonistic selection (a.k.a. intralocus sexual conflict), where the fitness of each sex is maximized by different genotypes at a locus. We show that balancing selection is common under biologically plausible conditions and that sex differences in selection or sex-by-genotype effects of mutations can each increase opportunities for balancing selection. Although heterozygote advantage and sexual antagonism represent alternative mechanisms for maintaining polymorphism, they mutually exist along a balancing selection continuum that depends on population and sex-specific parameters of selection and mutation. Sexual antagonism is the dominant mode of balancing selection across most of this continuum. Copyright © 2014 by the Genetics Society of America.
Burk, Linnea R; Armstrong, Jeffrey M; Goldsmith, H Hill; Klein, Marjorie H; Strauman, Timothy J; Costanzo, Phillip; Essex, Marilyn J
2011-03-01
Adolescent alcohol use is common and has serious immediate and long-term ramifications. While concurrent individual and context factors are robustly associated with adolescent alcohol use, the influence of early childhood factors, particularly in interaction with child sex, are less clear. Using a prospective community sample of 362 (190 girls), this study investigated sex differences in the joint influence of distal childhood and proximal adolescent factors on Grade 10 alcohol use. All risk factors and two-way early individual-by-context interactions, and interactions of each of these with child sex, were entered into the initial regression. Significant sex interactions prompted the use of separate models for girls and boys. In addition to the identification of early (family socioeconomic status, authoritative parenting style) and proximal adolescent (mental health symptoms, deviant friends) risk factors for both girls and boys, results highlighted important sex differences. In particular, girls with higher alcohol consumption at Grade 10 were distinguished by the interaction of early temperamental disinhibition and exposure to parental stress; boys with higher alcohol consumption at Grade 10 were distinguished primarily by early temperamental negative affect. Results have implications for the timing and type of interventions offered to adolescents.
Burk, Linnea R.; Armstrong, Jeffrey M.; Goldsmith, H. Hill; Klein, Marjorie H.; Strauman, Timothy J.; Costanzo, Phillip; Essex, Marilyn J.
2011-01-01
Adolescent alcohol use is common and has serious immediate and long-term ramifications. While concurrent individual and context factors are robustly associated with adolescent alcohol use, the influence of early childhood factors, particularly in interaction with child sex, are less clear. Using a prospective community sample of 362 (190 girls), this study investigated sex differences in the joint influence of distal childhood and proximal adolescent factors on Grade 10 alcohol use. All risk factors and 2-way early individual-by-context interactions, and interactions of each of these with child sex, were entered into the initial regression. Significant sex interactions prompted the use of separate models for girls and boys. In addition to the identification of early (family socioeconomic status, authoritative parenting style) and proximal adolescent (mental health symptoms, deviant friends) risk factors for both girls and boys, results highlighted important sex differences. In particular, girls with higher alcohol consumption at Grade 10 were distinguished by the interaction of early temperamental disinhibition and exposure to parental stress; boys with higher alcohol consumption at Grade 10 were distinguished primarily by early temperamental negative affect. Results have implications for the timing and type of interventions offered to adolescents. PMID:21443307
The Effect of Sex and Gender on Diabetic Complications.
Seghieri, Giuseppe; Policardo, Laura; Anichini, Roberto; Franconi, Flavia; Campesi, Ilaria; Cherchi, Sara; Tonolo, Giancarlo
2017-01-01
While in non-diabetic people the risk for cardiovascular disease is higher in men, diabetes completely reverts this sex-gender difference conferring to women a greater burden of cardiovascular complications. Additionally, all risk factors associated with cardiovascular disease appear to be more active in diabetic females than in their male counterparts. The reasons of this different impact of diabetes between genders are not completely clear. The aim of this review is trying to clarify these issues in a sex and gender perspective. Both genetic and hormonal factors are at the basis of sex-gender differences in diabetes, even do not explain the totality of data. Possibly women arrive later and in worse conditions to the diagnosis of diabetes, receive both diagnostic and therapeutic supports in a lesser measure and, finally, reach therapeutic goals as recommended by guidelines in a lesser extent. Further aspects of sex-gender differences in diabetic complications are represented by a more frequent prevalence of drug side effects in women, as well as by increased resistance to the action of drugs used in prevention or in the therapy of cardiovascular diseases. As to microvascular complications, the issue of sex-gender differences is even more complex, with some important differences emerging in experimental models 'in vitro', as well as in human pathology 'in vivo'. The main problem, however, also in this case, is that it is difficult to differentiate how common pathogenetic mechanisms acting in diabetes may differently impact between genders. In conclusion what is evident is that diabetes represents a 'risk magnifier' for the damage of both micro and macrovessels differently in men and in women. This issue deserves, therefore, a more careful approach from people involved in both clinical aspects and research regarding diabetes and its complications, in a sex-gender oriented perspective. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Dudycha, Jeffry L; Snoke-Smith, Margaret; Alía, Ricardo
2013-02-01
Genetic correlations among traits alter evolutionary trajectories due to indirect selection. Pleiotropy, chance linkage, and selection can all lead to genetic correlations, but have different consequences for phenotypic evolution. We sought to assess the mechanisms contributing to correlations with size at maturity in the cyclic parthenogen Daphnia pulicaria. We selected on size in each of four populations that differ in the frequency of sex, and evaluated correlated responses in a life table. Size at advanced adulthood, reproductive output, and adult growth rate clearly showed greater responses in high-sex populations, with a similar pattern in neonate size and r. This pattern is expected only when trait correlations are favored by selection and the frequency of sex favors the creation and demographic expansion of highly fit clones. Juvenile growth and age at maturity did not diverge consistently. The inter-clutch interval appeared to respond more strongly in low-sex populations, but this was not statistically significant. Our data support the hypothesis that correlated selection is the strongest driver of genetic correlations, and suggest that in organisms with both sexual and asexual reproduction, adaptation can be enhanced by recombination.
Sex differences in color preferences transcend extreme differences in culture and ecology.
Sorokowski, Piotr; Sorokowska, Agnieszka; Witzel, Christoph
2014-10-01
At first glance, color preferences might seem to be the most subjective and context-dependent aspects of color cognition. Yet they are not. The present study compares color preferences of women and men from an industrialized and a remote, nonindustrialized culture. In particular, we investigated preferences in observers from Poland and from the Yali in Papua, respectively. Not surprisingly, we found that color preferences clearly differed between the two communities and also between sexes. However, despite the pronounced cultural differences, the way in which men and women differed from each other was almost the same in both cultures. At the same time, this sexual contrast was not specific to biological components of color vision. Our results reveal a pattern of sexual dimorphism that transcends extreme differences in culture and ecology. They point toward strong cross-cultural constraints beyond the biological predispositions of nature and the cultural particularities of nurture.
Psychometric analysis of five measures of spatial ability.
Hogan, Thomas P
2012-02-01
This study analyzed psychometric properties of five measures of spatial ability on 96 young adults, with supplementary analysis for three of the measures on another sample of 71 young adults. Two measures were taken from the widely cited Kit of Factor-Referenced Cognitive Tests and three other measures were taken from a relatively new source originally intended as laboratory demonstrations. Previous research provided limited information on the psychometric properties of the measures. All five measures yielded adequate reliability and loaded on a single factor. Three measures yielded markedly skewed distributions. Two measures showed clear sex differences with men scoring higher but this difference seemed contaminated by a speed factor; three measures did not show a sex difference. Recommendations for use of the measures in future studies are provided.
Sex differences in cognitive impairment in Alzheimer’s disease
Laws, Keith R; Irvine, Karen; Gale, Tim M
2016-01-01
Sex differences in neurocognitive abilities have been extensively explored both in the healthy population and in many disorders. Until recently, however, little work has examined such differences in people with Alzheimer’s disease (AD). This is despite clear evidence that AD is more prevalent in women, and converging lines of evidence from brain imaging, post-mortem analyses, hormone therapy and genetics suggesting that AD affects men and women differently. We provide an overview of evidence attesting to the poorer cognitive profiles in women than in men at the same stage of AD. Indeed, men significantly outperform women in several cognitive domains, including: Language and semantic abilities, visuospatial abilities and episodic memory. These differences do not appear to be attributable to any differences in age, education, or dementia severity. Reasons posited for this female disadvantage include a reduction of estrogen in postmenopausal women, greater cognitive reserve in men, and the influence of the apolipoprotein E ε4 allele. Assessment of cognitive abilities contributes to the diagnosis of the condition and thus, it is crucial to identify the role of sex differences if potentially more accurate diagnoses and treatments are to emerge. PMID:27014598
Sex differences in nicotine preference.
Pogun, Sakire; Yararbas, Gorkem; Nesil, Tanseli; Kanit, Lutfiye
2017-01-02
Smoking is the major cause of preventable deaths worldwide, and although there is a decline in overall smoking prevalence in developed countries, the decline in women is less pronounced than in men. Women become dependent faster and experience greater difficulties in quitting. Similar trends have been observed in animal models of nicotine/tobacco addiction. Individual differences in vulnerability to drug abuse are also observed in nicotine/tobacco addiction and point to the importance of sex differences. This Review, summarizes findings from three experimental approaches used to depict nicotine preference in animal models, intravenous and oral nicotine self-administration and nicotine-induced conditioned place preference. Nicotine preference is considered to be reflected in the animal's motivation to administer the drug (intravenously or orally) or to prefer an environment paired with the presence of the drug (conditioned place preference). These approaches all point to the importance of sex and age of the subjects; the preference of females and adolescents appear to be more pronounced than that of males and adults, respectively. A closer look at these factors will help us understand the mechanisms that underlie nicotine addiction and develop strategies to cope. Ignoring sex differences and reaching conclusions based only on studies using male subjects has resulted in erroneous generalizations in the past. Sex differences in nicotine preference have been clearly documented, and awareness on this aspect of nicotine dependence will significantly impact our success in translational research. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
From Psychotherapy to Sex Therapy
ERIC Educational Resources Information Center
LoPiccolo, Joseph
1977-01-01
This review of the current state of affairs in the enterprise of sex therapy makes it clear that quality controls are lacking. In the absence of effective controls, the patient couple seeking sex therapy must be very wary before entering treatment. (Author/AM)
Ahrenfeldt, Linda Juel; Larsen, Lisbeth Aagaard; Lindahl-Jacobsen, Rune; Skytthe, Axel; Hjelmborg, Jacob v.B.; Möller, Sören; Christensen, Kaare
2017-01-01
Purpose To investigate the twin testosterone transfer (TTT) hypothesis by comparing early-life mortality risks of opposite-sex (OS) and same-sex (SS) twins during the first 15 years of life. Methods We performed a population-based cohort study to compare mortality in OS and SS twins. We included 68,629 live-born Danish twins from 1973 to 2009 identified through the Danish Twin Registry and performed piecewise stratified Cox regression and log-binomial regression. Results Among 1933 deaths, we found significantly higher mortality for twin boys than for twin girls. For both sexes, OS twins had lower mortality than SS twins; the difference persisted for the first year of life for boys and for the first week of life for girls. Conclusions Although the mortality risk for OS boys was in the expected direction according to the TTT hypothesis, the results for OS girls pointed in the opposite direction, providing no clear evidence for the TTT hypothesis. PMID:28024904
Response format, magnitude of laterality effects, and sex differences in laterality.
Voyer, Daniel; Doyle, Randi A
2012-01-01
The present study examined the evidence for the claim that response format might affect the magnitude of laterality effects by means of a meta-analysis. The analysis included the 396 effect sizes drawn from 266 studies retrieved by Voyer (1996) and relevant to the main effect of laterality and sex differences in laterality for verbal and non-verbal tasks in the auditory, tactile, and visual sensory modality. The response format used in specific studies was the only moderator variable of interest in the present analysis, resulting in four broad response categories (oral, written, computer, and pointing). A meta-analysis analogue to ANOVA showed no significant influence of response format on either the main effect of laterality or sex differences in laterality when all sensory modalities were combined. However, when modalities were considered separately, response format affected the main effect of laterality in the visual modality, with a clear advantage for written responses. Further pointed analyses revealed some specific differences among response formats. Results are discussed in terms of their implications for the measurement of laterality.
Sex differences in the toxicity of polyethylene glycol-coated gold nanoparticles in mice
Chen, Jie; Wang, Hao; Long, Wei; Shen, Xiu; Wu, Di; Song, Sha-Sha; Sun, Yuan-Ming; Liu, Pei-Xun; Fan, Saijun; Fan, Feiyue; Zhang, Xiao-Dong
2013-01-01
Gold nanoparticles have received wide interest in disease diagnosis and therapy, but one of the important issues is their toxicological effects in vivo. Sex differences in the toxicity of gold nanoparticles are not clear. In this work, body weight, organ weight, hematology, and biochemistry were used to evaluate sex differences in immune response and liver and kidney damage. Pathology was used to observe the general toxicity of reproductive organs. The immune response was influenced significantly in female mice, with obvious changes in spleen and thymus index. Hematology results showed that male mice treated with 22.5 nm gold nanoparticles received more significant infection and inflammation than female mice. Meanwhile, the biochemistry results showed that 4.4 and 22.5 nm gold nanoparticles caused more significant liver damage in male mice than female mice, while 22.5, 29.3, and 36.1 nm gold nanoparticles caused more significant kidney damage in female mice than male mice. No significant toxicological response was found in the reproductive system for female or male mice. It was found that gold nanoparticles caused more serious liver toxicity and infection in male mice than female mice. These findings indicated that sex differences may be one of the important elements for in vivo toxicity of gold nanoparticles. PMID:23861586
The Psychometrics of the Mini-K.
Richardson, George B; Chen, Ching-Chen; Dai, Chia-Liang; Brubaker, Michael D; Nedelec, Joseph L
2017-01-01
Many published studies have employed the Mini-K to measure a single fast-slow life history dimension. However, the internal structure of the Mini-K has not been determined and it is not clear that a single higher order K-factor fits the data. It is also not clear that the Mini-K is measurement invariant across groups such as the sexes. To establish the construct validity of K as well as the broader usefulness of applying life history theory to humans, it is crucial that these psychometric issues are addressed as a part of measure validation efforts. Here we report on three studies that used latent variable modeling and data drawn from two college student samples ( ns = 361 and 300) to elucidate the psychometrics of the Mini-K. We found that (a) the Mini-K had a six dimensional first-order structure, (b) the K-factor provided a parsimonious explanation of the associations among the lower order factors at no significant cost to fit, (c) the Mini-K measured the same K-factor across the sexes, (d) K-factor means did not have the same meaning across the sexes and thus the first-order factors should be used in studies of mean sex differences, and finally, (e) the K-factor was only associated with environment and aspects of mating competition in females. Implications and future directions for life history research are discussed.
Condom Nation: The U.S. Government's Sex Education Campaign from World War I to the Internet
ERIC Educational Resources Information Center
Lord, Alexandra M.
2009-01-01
This history of the U.S. Public Health Service's efforts to educate Americans about sex makes clear why federally funded sex education has been haphazard, ad hoc, and often ineffectual. Since launching its first sex ed program during World War I, the Public Health Service has dominated federal sex education efforts. Alexandra M. Lord draws on…
Jensen, Kim; McClure, Colin; Priest, Nicholas K; Hunt, John
2015-01-01
Modest dietary restriction extends lifespan (LS) in a diverse range of taxa and typically has a larger effect in females than males. Traditionally, this has been attributed to a stronger trade-off between LS and reproduction in females than in males that is mediated by the intake of calories. Recent studies, however, suggest that it is the intake of specific nutrients that extends LS and mediates this trade-off. Here, we used the geometric framework (GF) to examine the sex-specific effects of protein (P) and carbohydrate (C) intake on LS and reproduction in Drosophila melanogaster. We found that LS was maximized at a high intake of C and a low intake of P in both sexes, whereas nutrient intake had divergent effects on reproduction. Male offspring production rate and LS were maximized at the same intake of nutrients, whereas female egg production rate was maximized at a high intake of diets with a P:C ratio of 1:2. This resulted in larger differences in nutrient-dependent optima for LS and reproduction in females than in males, as well as an optimal intake of nutrients for lifetime reproduction that differed between the sexes. Under dietary choice, the sexes followed similar feeding trajectories regulated around a P:C ratio of 1:4. Consequently, neither sex reached their nutritional optimum for lifetime reproduction, suggesting intralocus sexual conflict over nutrient optimization. Our study shows clear sex differences in the nutritional requirements of reproduction in D. melanogaster and joins the growing list of studies challenging the role of caloric restriction in extending LS. PMID:25808180
Biological sex and the risk of cerebral palsy in Victoria, Australia.
Reid, Susan M; Meehan, Elaine; Gibson, Catherine S; Scott, Heather; Delacy, Michael J
2016-02-01
Males typically outnumber females in cerebral palsy (CP) cohorts. To better understand this 'male disadvantage' and provide insight into causal pathways to CP, this study used 1983 to 2009 Australian CP and population birth cohorts to identify associations and trends with respect to biological sex and CP. Within birth gestation groups, sex ratios were calculated to evaluate any male excess in the CP cohort compared with livebirths, neonatal deaths, neonatal mortality and survival rates, neonatal survivors, and CP rates in survivors. Sex- and gestation-specific trends in neonatal mortality, CP rates, and CP sex ratios were assessed by plotting their annual frequencies and fitting quadratic curves. Over-representation of males in preterm live births partly explained the male excess in the CP cohort after preterm birth, especially at 28 to 31 weeks. Higher CP rates in male neonatal survivors also contributed to the male excess in CP, particularly at <28 and 37+ weeks. Higher neonatal mortality rates in males at all gestations had little impact on the CP sex ratio. There was no clearly discernible change over time in the CP sex ratio. Gestation-specific associations between sex and CP provide insight into causal pathways to CP and suggest sex-specific differences in response to neuroprotective strategies. © 2016 The Authors. Developmental Medicine & Child Neurology © 2016 Mac Keith Press.
Rauschert, Sebastian; Uhl, Olaf; Koletzko, Berthold; Mori, Trevor A; Beilin, Lawrence J; Oddy, Wendy H; Hellmuth, Christian
2017-01-01
There are differences in the prevalence and severity of diseases between males, females not taking hormonal contraceptives (non-HC females) and females taking hormonal contraceptives (HC females). The aim of this study was to identify sex-specific differences in the metabolome and its relation to components of the metabolic syndrome in a young adult population. The subjects analysed are from the 20-year follow-up of the Western Australian Pregnancy Cohort (Raine) Study. Two hundred fifteen plasma metabolites were analysed in 1021 fasted plasma samples by a targeted liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) metabolomics approach. Principal component analysis between males ( n = 550), non-HC females ( n = 199) and HC females ( n = 269) was applied. Regression analysis with a sex × metabolite concentration interaction was performed on components of the MetS, namely waist circumference, systolic blood pressure, and plasma HDL-C, triglycerides and glucose concentration, as outcome to select the significant metabolites of the interaction. Those selected metabolites were used as predictors in a sex group stratified analysis to compare the different β coefficients and therefore the sex group-dependent associations. Principal component analysis between males, non-HC females, and HC females showed a general discriminating trend between males and HC females. One hundred twenty-seven metabolites were significantly different between males and non-HC females, whereas 97 differed between non-HC females and HC females. Males and non-HC females mainly differed in sphingomyelin, lyso-phosphatidylcholine, acyl-carnitine and amino acid species, whilst non-HC females and HC females mainly differed in phosphatidylcholine, lyso-phosphatidylcholine and acyl-carnitine concentrations. Forty-one metabolites (phosphatidylcholines, sphingomyelines, lyso-phosphatidylcholine) were significantly differently associated with the MetS factors in the different groups. We have shown clear differences between plasma metabolite concentrations in males, and HC or non-HC females, especially in lyso-phosphatidylcholine, sphingomyelin and phosphatidylcholine, which have been shown to associate with obesity in other studies. The association of these metabolites differed between sexes with components of the metabolic syndrome, which means that development of diseases like obesity and diabetes may differ between the sexes. Our findings highlight the importance of considering sex differences when conducting a metabolomics study and the need to account for the effect of HC usage in females in future studies.
ERIC Educational Resources Information Center
Friedman, Howard S.
1979-01-01
Students' perceptions of sincerity, dominance, and positivity were measured by pairing happy, angry, surprised and sad faces of teachers with teachers' comments characterized as positive or negative and dominant or submissive. Clear effects of facial-verbal combinations emerged; there were no sex differences other than in perceptions of sincerity.…
Teenagers Whose Moms Worked: Did It Make a Difference?
ERIC Educational Resources Information Center
Knoblach, Robin; Chambliss, Catherine
One of the fastest growing social and economic trends in the latter half of this century has been the entry of women into the labor force, especially women with children. How a mother's working outside the home affects her children is far from clear. This study examined the relationship between maternal employment status and sex-role concept,…
Addressing Sexual Harassment on Campus. ERIC Digest.
ERIC Educational Resources Information Center
Holub, Jonathan
Although data on sexual harassment in the community college is limited, it is clear that it does exist and that it runs counter to the colleges' educational mission. Sexual harassment has been defined as verbal or physical conduct of a sexual nature, imposed on the basis of sex, that denies, limits, or provides different treatment. Recent legal…
Sex Bias in Infectious Disease Epidemiology: Patterns and Processes
Guerra-Silveira, Felipe; Abad-Franch, Fernando
2013-01-01
Background Infectious disease incidence is often male-biased. Two main hypotheses have been proposed to explain this observation. The physiological hypothesis (PH) emphasizes differences in sex hormones and genetic architecture, while the behavioral hypothesis (BH) stresses gender-related differences in exposure. Surprisingly, the population-level predictions of these hypotheses are yet to be thoroughly tested in humans. Methods and Findings For ten major pathogens, we tested PH and BH predictions about incidence and exposure-prevalence patterns. Compulsory-notification records (Brazil, 2006–2009) were used to estimate age-stratified ♂:♀ incidence rate ratios for the general population and across selected sociological contrasts. Exposure-prevalence odds ratios were derived from 82 published surveys. We estimated summary effect-size measures using random-effects models; our analyses encompass ∼0.5 million cases of disease or exposure. We found that, after puberty, disease incidence is male-biased in cutaneous and visceral leishmaniasis, schistosomiasis, pulmonary tuberculosis, leptospirosis, meningococcal meningitis, and hepatitis A. Severe dengue is female-biased, and no clear pattern is evident for typhoid fever. In leprosy, milder tuberculoid forms are female-biased, whereas more severe lepromatous forms are male-biased. For most diseases, male bias emerges also during infancy, when behavior is unbiased but sex steroid levels transiently rise. Behavioral factors likely modulate male–female differences in some diseases (the leishmaniases, tuberculosis, leptospirosis, or schistosomiasis) and age classes; however, average exposure-prevalence is significantly sex-biased only for Schistosoma and Leptospira. Conclusions Our results closely match some key PH predictions and contradict some crucial BH predictions, suggesting that gender-specific behavior plays an overall secondary role in generating sex bias. Physiological differences, including the crosstalk between sex hormones and immune effectors, thus emerge as the main candidate drivers of gender differences in infectious disease susceptibility. PMID:23638062
Ishii, Hironori; Onodera, Mariko; Ohara, Shinya; Tsutsui, Ken-Ichiro; Iijima, Toshio
2018-01-01
Different biological requirements between males and females may cause sex differences in decision preference when choosing between taking a risk to get a higher gain or taking a lower but sure gain. Several studies have tested this assumption in rats, however the conclusion remains controversial because the previous real-world like gambling tasks contained a learning component to track a global payoff of probabilistic outcome in addition to risk preference. Therefore, we modified a simple gambling task allowing us to exclude such learning effect, and investigated the sex difference in risk preference of rats and its neural basis. The task required water deprived rats to choose between a risky option which provided four drops of water or no reward at a 50% random chance vs. a sure option which provided predictable amount x (x = 1, 2, 3, 4). The amount and the risk were explicitly instructed so that different choice conditions could be tested trial by trial without re-learning of reward contingency. Although both sexes correctly chose the sure option with the same level of accuracy when the sure option provided the best offer (x = 4), they exhibited different choice performances when two options had the same expected value (x = 2). Males and females both preferred to take risky choices than sure choices (risk seeking), but males were more risk seeking than females. Outcome-history analysis of their choice pattern revealed that females reduced their risk preference after losing risky choices, whereas males did not. Rather, as losses continued, reaction time for subsequent risky choices got shorter in males. Given that significant sex difference features mainly emerged after negative experiences, male and female rats may evaluate an unsuccessful outcome of their decision in different manners. Furthermore, c-Fos expression in the paraventricular nucleus of the thalamus (PV) was higher in the gambling task than for the control task in males while c-fos levels did not differ in females. The present study provides a clear evidence of sex differences in risk preference in rats and suggests that the PV is a candidate region contributing to sex differences in risky decision making. PMID:29692713
Interventions That Affect Gender Bias in Hiring: A Systematic Review
Isaac, Carol; Lee, Barbara; Carnes, Molly
2015-01-01
Purpose To systematically review experimental evidence for interventions mitigating gender bias in employment. Unconscious endorsement of gender stereotypes can undermine academic medicine's commitment to gender equity. Method The authors performed electronic and hand searches for randomized controlled studies since 1973 of interventions that affect gender differences in evaluation of job applicants. Twenty-seven studies met all inclusion criteria. Interventions fell into three categories: application information, applicant features, and rating conditions. Results The studies identified gender bias as the difference in ratings or perceptions of men and women with identical qualifications. Studies reaffirmed negative bias against women being evaluated for positions traditionally or predominantly held by men (male sex-typed jobs). The assessments of male and female raters rarely differed. Interventions that provided raters with clear evidence of job-relevant competencies were effective. However, clearly competent women were rated lower than equivalent men for male sex-typed jobs unless evidence of communal qualities was also provided. A commitment to the value of credentials before review of applicants and women's presence at above 25% of the applicant pool eliminated bias against women. Two studies found unconscious resistance to “antibias” training, which could be overcome with distraction or an intervening task. Explicit employment equity policies and an attractive appearance benefited men more than women, whereas repeated employment gaps were more detrimental to men. Masculine-scented perfume favored the hiring of both sexes. Negative bias occurred against women who expressed anger or who were perceived as self-promoting. Conclusions High-level evidence exists for strategies to mitigate gender bias in hiring. PMID:19881440
Kai, Kiyonori; Sahto, Hiroshi; Yoshida, Mitsuyoshi; Suzuki, Takami; Shikanai, Yukari; Kajimura, Tetsuyo; Furuhama, Kazuhisa
2006-01-01
Species and sex differences in susceptibility to vincristine sulphate (VCR)-induced olfactory epithelial lesions were investigated among the BALB/c mice, Crj: CD(SD) IGS rats and common marmoset monkeys following a single intravenous administration on day 1. As dosage levels, the 0.17-fold LD10, 0.6-fold LD10 and LD10 were used for mice and rats, and a maximum tolerated dose (MTD) was chosen only for monkeys. The order of strength of VCR action on peripheral neuropathic signs, body weight gain, and hematological parameters was mice > rats > monkeys, without clear sex differences. Histopathologically, on day 2, single cell death in the olfactory epithelium and vomeronasal organ was observed only in male mice at LD10, and in female mice at 0.6-fold LD10 or more. On day 5, the olfactory epithelium in these mice showed regenerative proliferation suggesting a sign of recovery. On day 10, axonopathy and demyelination in the sciatic and trigeminal nerves were noted in mice of both sexes at 0.6-fold LD10 or more. In rats and monkeys of either sex, however, no morphological changes were observed at any dose level. In conclusion, mice, particularly females, were shown to be more susceptible to VCR-induced apoptosis in the olfactory epithelium than rats and monkeys.
Circadian Rhythms Differ between Sexes and Closely Related Species of Nasonia Wasps
Bertossa, Rinaldo C.; van Dijk, Jeroen; Diao, Wenwen; Saunders, David; Beukeboom, Leo W.; Beersma, Domien G. M.
2013-01-01
Activity rhythms in 24 h light-dark cycles, constant darkness, and constant light conditions were analyzed in four different Nasonia species for each sex separately. Besides similarities, clear differences are evident among and within Nasonia species as well as between sexes. In all species, activity in a light-dark cycle is concentrated in the photophase, typical for diurnal organisms. Contrary to most diurnal insect species so far studied, Nasonia follows Aschoff's rule by displaying long (>24 h) internal rhythms in constant darkness but short (<24 h) in constant light. In constant light, N. vitripennis males display robust circadian activity rhythms, whereas females are usually arrhythmic. In contrast to other Nasonia species, N. longicornis males display anticipatory activity, i.e. activity shortly before light-on in a light-dark cycle. As expected, N. oneida shows activity patterns similar to those of N. giraulti but with important differences in key circadian parameters. Differences in circadian activity patterns and parameters between species may reflect synchronization of specific life-history traits to environmental conditions. Scheduling mating or dispersion to a specific time of the day could be a strategy to avoid interspecific hybridization in Nasonia species that live in sympatry. PMID:23555911
Mills, T C; Stall, R; Pollack, L; Paul, J P; Binson, D; Canchola, J; Catania, J A
2001-01-01
OBJECTIVES: This study investigated the limitations of probability samples of men who have sex with men (MSM), limited to single cities and to the areas of highest concentrations of MSM ("gay ghettos"). METHODS: A probability sample of 2881 MSM in 4 American cities completed interviews by telephone. RESULTS: MSM who resided in ghettos differed from other MSM, although in different ways in each city. Non-ghetto-dwelling MSM were less involved in the gay and lesbian community. They were also less likely to have only male sexual partners, to identify as gay, and to have been tested for HIV. CONCLUSIONS: These differences between MSM who live in gay ghettos and those who live elsewhere have clear implications for HIV prevention efforts and health care planning. PMID:11392945
Sex differences in empathy for pain: What is the role of autonomic regulation?
Tracy, Lincoln M; Giummarra, Melita J
2017-10-01
Empathy involves both affective and cognitive components whereby we understand, and express concerns for, the experiences of others. Women typically have superior trait empathy compared with men, which seems to have a neurological basis with sex differences in the structure and function of neural networks involved in empathy. This study investigated sex differences in empathy for pain using the Empathy for Pain Scale, and examined whether these trait differences were associated with disruptions in autonomic regulation, specifically via the parasympathetic nervous system (measured through the square root of the mean squared differences of successive R-R intervals; RMSSD) both at rest and during a socioevaluative stress task (i.e., the serial sevens task). Compared with men, women reported higher empathic concern (Cohen's r = .25) and affective distress (Cohen's d = 0.65) toward another in pain. In both men and women, there was a decrease in lnRMSSD in the stress task compared to rest. Sex moderated the relationship between resting lnRMSSD and self-reported empathic concern. Specifically, there was no clear association between empathic concern and lnRMSSD in men whereas in women there was a negative relationship, with lower resting lnRMSSD associated with higher empathic concern, and higher lnRMSSD associated with lower levels of empathic concern that were similar to men. These findings suggest that empathic feelings may result from poorer psychophysiological regulation, and concur with previous research displaying sex-specific relationships between resting heart rate variability and emotion regulation abilities. © 2017 Society for Psychophysiological Research.
Rodriguez-Cuenca, S; Monjo, M; Proenza, A M; Roca, P
2005-01-01
Sex hormones play an important role in adipose tissue metabolism by activating specific receptors that alter several steps of the lipolytic and lipogenic signal cascade in depot- and sex-dependent manners. However, studies focusing on steroid receptor status in adipose tissue are scarce. In the present study, we analyzed steroid content [testosterone (T), 17beta-estradiol (17beta-E2), and progesterone (P4)] and steroid receptor mRNA levels in different rat adipose tissue depots. As expected, T levels were higher in males than in females (P = 0.031), whereas the reverse trend was observed for P4 (P < 0.001). It is noteworthy that 17beta-E2 adipose tissue levels were higher in inguinal than in the rest of adipose tissues for both sexes, where no sex differences in 17beta-E2 tissue levels were noted (P = 0.010 for retroperitoneal, P = 0.005 for gonadal, P = 0.018 for mesenteric). Regarding steroid receptor levels, androgen (AR) and estrogen receptor (ER)alpha and ERbeta densities were more clearly dependent on adipose depot location than on sex, with visceral depots showing overall higher mRNA densities than their subcutaneous counterparts. Besides, expression of ERalpha predominated over ERbeta expression, and progesterone receptor (PR-B form and PR-A+B form) mRNAs were identically expressed regardless of anatomic depot and sex. In vitro studies in 3T3-L1 cells showed that 17beta-E2 increased ERalpha (P = 0.001) and AR expression (P = 0.001), indicating that estrogen can alter estrogenic and androgenic signaling in adipose tissue. The results highlighted in this study demonstrate important depot-dependent differences in the sensitivity of adipose tissues to sex hormones between visceral and subcutaneous depots that could be related to metabolic situations observed in response to sex hormones.
Pfingstl, Tobias
2013-10-01
The population dynamics of the three intertidal oribatid species, Alismobates inexpectatus, Fortuynia atlantica and Carinozetes bermudensis, have been studied on the archipelago of Bermuda over the course of a year. All three species are univoltine, showing a clear seasonal demographic pattern, with reproduction from spring to late autumn and a complete standstill of egg production in winter. A seasonal shift in sex ratio could also be observed in all three species and is supposed to be based on sex-dependent mortality. The subtropical climate of Bermuda allows longer reproductive periods than shown in other intertidal or edaphic temperate species and temperature is supposed to be the main factor influencing the demography of these intertidal dwelling mites. Although all three Bermudian species exhibit the same basic seasonal demographic pattern, there are slight temporal shifts in population dynamics, presumably caused by local microclimatic differences among the populations. Larviparity, shown in other littoral oribatid mites, is clearly absent in the present species.
ERIC Educational Resources Information Center
Casas, Ferran; Gonzalez, Monica; Figuer, Cristina; Coenders, Germa
2004-01-01
The relation between life domains satisfaction and overall life satisfaction, values, internal/external perceived control and the option of planning or by chance searching information on the Internet has been explored in a sample of Spanish adolescents aged 12 to 16 (N=968). Age and sex differences have been examined. Results clearly confirm a…
Karmakar, Bibha; Malkin, Ida; Kobyliansky, Eugene
2013-06-01
Dermatoglyphic asymmetry and diversity traits from a large number of twins (MZ and DZ) were analyzed based on principal factors to evaluate genetic effects and common familial environmental influences on twin data by the use of maximum likelihood-based Variance decomposition analysis. Sample consists of monozygotic (MZ) twins of two sexes (102 male pairs and 138 female pairs) and 120 pairs of dizygotic (DZ) female twins. All asymmetry (DA and FA) and diversity of dermatoglyphic traits were clearly separated into factors. These are perfectly corroborated with the earlier studies in different ethnic populations, which indicate a common biological validity perhaps exists of the underlying component structures of dermatoglyphic characters. Our heritability result in twins clearly showed that DA_F2 is inherited mostly in dominant type (28.0%) and FA_F1 is additive (60.7%), but no significant difference in sexes was observed for these factors. Inheritance is also very prominent in diversity Factor 1, which is exactly corroborated with our previous findings. The present results are similar with the earlier results of finger ridge count diversity in twin data, which suggested that finger ridge count diversity is under genetic control.
Jensen, Kim; McClure, Colin; Priest, Nicholas K; Hunt, John
2015-08-01
Modest dietary restriction extends lifespan (LS) in a diverse range of taxa and typically has a larger effect in females than males. Traditionally, this has been attributed to a stronger trade-off between LS and reproduction in females than in males that is mediated by the intake of calories. Recent studies, however, suggest that it is the intake of specific nutrients that extends LS and mediates this trade-off. Here, we used the geometric framework (GF) to examine the sex-specific effects of protein (P) and carbohydrate (C) intake on LS and reproduction in Drosophila melanogaster. We found that LS was maximized at a high intake of C and a low intake of P in both sexes, whereas nutrient intake had divergent effects on reproduction. Male offspring production rate and LS were maximized at the same intake of nutrients, whereas female egg production rate was maximized at a high intake of diets with a P:C ratio of 1:2. This resulted in larger differences in nutrient-dependent optima for LS and reproduction in females than in males, as well as an optimal intake of nutrients for lifetime reproduction that differed between the sexes. Under dietary choice, the sexes followed similar feeding trajectories regulated around a P:C ratio of 1:4. Consequently, neither sex reached their nutritional optimum for lifetime reproduction, suggesting intralocus sexual conflict over nutrient optimization. Our study shows clear sex differences in the nutritional requirements of reproduction in D. melanogaster and joins the growing list of studies challenging the role of caloric restriction in extending LS. © 2015 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.
The genetic architecture of liver enzyme levels: GGT, ALT and AST.
van Beek, Jenny H D A; de Moor, Marleen H M; de Geus, Eco J C; Lubke, Gitta H; Vink, Jacqueline M; Willemsen, Gonneke; Boomsma, Dorret I
2013-07-01
High levels of liver enzymes GGT, ALT and AST are predictive of disease and all-cause mortality and can reflect liver injury, fatty liver and/or oxidative stress. Variation in GGT, ALT and AST levels is heritable. Moderation of the heritability of these liver enzymes by age and sex has not often been explored, and it is not clear to what extent non-additive genetic and shared environmental factors may play a role. To examine the genetic architecture of GGT, ALT and AST, plasma levels were assessed in a large sample of twins, their siblings, parents and spouses (N = 8,371; age range 18-90). For GGT and ALT, but not for AST, genetic structural equation modeling showed evidence for quantitative sex differences in the genetic architecture. There was no evidence for qualitative sex differences, i.e. the same genes were expressed in males and females. Both additive and non-additive genetic factors were important for GGT in females (total heritability h(2) 60 %) and AST in both sexes (total h(2) 43 %). The heritability of GGT in males and ALT for both sexes was due to additive effects only (GGT males 30 %; ALT males 40 %, females 22 %). Evidence emerged for shared environmental factors influencing GGT in the male offspring generation (variance explained 28 %). Thus, the same genes influence liver enzyme levels across sex and age, but their relative contribution to the variation in GGT and ALT differs in males and females and for GGT across age. Given adequate sample sizes these results suggest that genome-wide association studies may result in the detection of new susceptibility loci for liver enzyme levels when pooling results over sex and age.
Male-female differences in Scoliosis Research Society-30 scores in adolescent idiopathic scoliosis.
Roberts, David W; Savage, Jason W; Schwartz, Daniel G; Carreon, Leah Y; Sucato, Daniel J; Sanders, James O; Richards, Benjamin Stephens; Lenke, Lawrence G; Emans, John B; Parent, Stefan; Sarwark, John F
2011-01-01
Longitudinal cohort study. To compare functional outcomes between male and female patients before and after surgery for adolescent idiopathic scoliosis (AIS). There is no clear consensus in the existing literature with respect to sex differences in functional outcomes in the surgical treatment of AIS. A prospective, consecutive, multicenter database of patients who underwent surgical correction for adolescent idiopathic scoliosis was analyzed retrospectively. All patients completed Scoliosis Research Society-30 (SRS-30) questionnaires before and 2 years after surgery. Patients with previous spine surgery were excluded. Data were collected for sex, age, Risser grade, previous bracing history, maximum preoperative Cobb angle, curve correction at 2 years, and SRS-30 domain scores. Paired sample t tests were used to compare preoperative and postoperative scores within each sex. Independent sample t tests were used to compare scores between sexes. A P value of <0.05 was considered statistically significant. Seven hundred forty-four patients (621 females and 123 males) were included. On average, males were 1 year older than females. There were no differences between sexes in Risser grade, bracing history, maximum curve magnitude, or correction after surgery. Both males and females had similar improvement in all SRS-30 domains after surgery. Self-image/appearance had the greatest relative improvement. Males had better self-image/appearance scores preoperatively, better pain scores at 2 years, and better mental health and total scores both preoperatively and at 2 years. Both males and females were similarly satisfied with surgery. Males treated with surgery for AIS report better preoperative self-image, less postoperative pain, and better mental health than females. These differences may be clinically significant. For both males and females, the most beneficial effect of surgery is improved self-image/appearance. Overall, the benefits of surgery for AIS are similar for both sexes.
Analysis of strontium metabolism in humans on the basis of the Techa river data
NASA Technical Reports Server (NTRS)
Tolstykh, E. I.; Kozheurov, V. P.; Vyushkova, O. V.; Degteva, M. O.; Neta, R. (Principal Investigator)
1997-01-01
Age and sex features of strontium metabolism have been analyzed on studies of the population residing on the banks of the Techa river which was contaminated by fission products during the years 1949-1956. Measurements of 90Sr body burden have been performed since 1974 using a whole-body counter, and these have made it possible to estimate age-specific long-term retention and elimination rates for men and women. Regarding the retention that correlated with the respective maturation ages, distinct sex differences have been observed for adolescents, whereas only postmenopausal women showed a sharp increase of their elimination rates. There were no differences concerning the reproductive ages. Our experimental findings have a clear physiological interpretation and can be used to develop metabolic models for bone-seeking radionuclides.
Parental attitudes toward adolescent sexuality: transcultural perspectives.
DeSantis, L; Thomas, J T
1987-08-01
The problem of teenage pregnancy continues to impact private and public resources, affecting all socioeconomic and cultural groups. A key factor for nurse practitioners to consider when planning sex education programs is the differing parental attitudes toward teenage sexuality. These attitudes are especially important to keep in mind when dealing with parents from minority cultural groups, as these groups are often highly influential in determining the nature of adolescent sexual behavior and attitudes toward reproduction. A study of Cuban and Haitian child-rearing practices clearly demonstrates two divergent parental views of adolescent sexuality. Nurse practitioners must recognize these differing views, and individualize their approach, in order to develop culturally sensitive sex education programs for adolescents and their parents. Suggestions are provided for development of such programs for Cuban and Haitian parents and children.
Sexing the brain: the science and pseudoscience of sex differences.
Rogers, Lesley J
2010-06-01
A recent upsurge in unitary biological explanations for gender differences in behavior (i.e. that they are "hard-wired" in the genetic code), put forward not only in books written for a general audience but also in scientific papers, makes it important to examine the fallacies of these ideas. Such genetic and hormonal explanations of human behavior, formulated with little consideration of the influences of experience, and often without taking experience into account at all, are part of a new wave of genetic explanations for a broad range of human behavior, as explained in the paper. These ideas are far from new; moreover, they are pseudoscientific and are used for political influence under the guise of science. They are a conservative social force that maintains social and educational inequalities between women and men. This paper explains that causal explanations of differences between the sexes are of two completely different types: unitary (genetic determinist) versus interactive explanations. The false reasoning used to support genetic determinist explanations of sex differences in behavior is discussed. To illustrate what biology really tells us about gender differentiation, the paper discusses the interactive roles of genetic, hormonal and environmental influences on the development of gender differences. These interactions are illustrated using two model biological systems (e.g. the intertwined influences of genes, sex hormones and experience on the development of sex differences in behavior in rats, and sex differences in neuronal connections in chickens). There is plenty of scientific evidence to show the complex interactive, and ever changing, influences of experience and genes that take place as an organism develops and throughout its life. Malleability of brain and behavior can be shown clearly using animal models, and the processes involved apply also to the development of brain and behavior in humans. We diminish our understanding of the functions of a host of contributing factors to gender differentiation by parceling out the largest portion of control to the genes. The biology and behavior of humans is dynamic and flexible and need not restrict women to inferior positions in society. 2010 Elsevier. Published by Elsevier B.V. All rights reserved.
Sarlo, Michela; Buodo, Giulia
2017-03-15
A large body of research on gender differences in response to erotic stimuli has focused on genital and/or subjective sexual arousal. On the other hand, studies assessing gender differences in emotional psychophysiological responding to sexual stimuli have only employed erotic pictures of male-female couples or female/male nudes. The present study aimed at investigating differences between gynephilic men and androphilic women in emotional responding to visual sexual stimuli depicting female-male, female-female and male-male couples. Affective responses were explored in multiple response systems, including autonomic indices of emotional activation, i.e., heart rate and skin conductance, along with standardized measures of valence and arousal. Blood pressure was measured as an index of autonomic activation associated with sexual arousal, and free viewing times as an index of interest/avoidance. Overall, men showed gender-specific activation characterized by clearly appetitive reactions to the target of their sexual attraction (i.e., women), with physiological arousal discriminating female-female stimuli as the most effective sexual cues. In contrast, women's emotional activation to sexual stimuli was clearly non-specific in most of the considered variables, with the notable exception of the self-report measures. Overall, affective responses replicate patterns of gender-specific and gender-nonspecific sexual responses in gynephilic men and androphilic women. Copyright © 2017 Elsevier Inc. All rights reserved.
Darda, Kohinoor M; Butler, Emily E; Ramsey, Richard
2018-06-01
Humans show an involuntary tendency to copy other people's actions. Although automatic imitation builds rapport and affiliation between individuals, we do not copy actions indiscriminately. Instead, copying behaviors are guided by a selection mechanism, which inhibits some actions and prioritizes others. To date, the neural underpinnings of the inhibition of automatic imitation and differences between the sexes in imitation control are not well understood. Previous studies involved small sample sizes and low statistical power, which produced mixed findings regarding the involvement of domain-general and domain-specific neural architectures. Here, we used data from Experiment 1 ( N = 28) to perform a power analysis to determine the sample size required for Experiment 2 ( N = 50; 80% power). Using independent functional localizers and an analysis pipeline that bolsters sensitivity, during imitation control we show clear engagement of the multiple-demand network (domain-general), but no sensitivity in the theory-of-mind network (domain-specific). Weaker effects were observed with regard to sex differences, suggesting that there are more similarities than differences between the sexes in terms of the neural systems engaged during imitation control. In summary, neurocognitive models of imitation require revision to reflect that the inhibition of imitation relies to a greater extent on a domain-general selection system rather than a domain-specific system that supports social cognition.
Król-Zielińska, Magdalena; Kusy, Krzysztof; Zieliński, Jacek; Osiński, Wiesław
2011-01-01
The purpose of the study was to compare the level of energy expenditure due to physical activity (EEPA) and functional fitness (FF) in 59 women and 82 men aged 70-80 years, divided into three groups: permanent residents in assisted-living facilities (ALFs), participants in adult day care centers (DCCs) and older people living independently, members in community senior centers (CSCs). EEPA and FF were analyzed taking into consideration sex differences. The energy expenditure tended to be lower in DCCs and ALFs subjects than in CSCs members, but significant differences were obtained only in women. Women in different living settings differed only in endurance. In men, the differences were clear in most tests (endurance, strength, agility/dynamic balance) except for flexibility. Institutionalization was connected with a significantly lower level of FF and equalization of sex differences. Education seemed to be an important factor influencing the level of FF in men. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.
Sex differences in genetic and environmental influences on educational attainment and income.
Orstavik, Ragnhild E; Czajkowski, Nikolai; Røysamb, Espen; Knudsen, Gun Peggy; Tambs, Kristian; Reichborn-Kjennerud, Ted
2014-12-01
In many Western countries, women now reach educational levels comparable to men, although their income remains considerably lower. For the past decades, it has become increasingly clear that these measures of socio-economic status are influenced by genetic as well as environmental factors. Less is known about the relationship between education and income, and sex differences. The aim of this study was to explore genetic and environmental factors influencing education and income in a large cohort of young Norwegian twins, with special emphasis on gender differences. National register data on educational level and income were obtained for 7,710 twins (aged 29-41 years). Bivariate Cholesky models were applied to estimate qualitative and quantitative gender differences in genetic and environmental influences, the relative contribution of genetic and environmental factors to the correlation between education and income, and genetic correlations within and between sexes and phenotypes. The phenotypic correlation between educational level and income was 0.34 (0.32-0.39) for men and 0.45 (0.43-0.48) for women. An ACE model with both qualitative and quantitative sex differences fitted the data best. The genetic correlation between men and women (rg) was 0.66 (0.22-1.00) for educational attainment and 0.38 (0.01-0.75) for income, and between the two phenotypes 0.31 (0.08-0.52) for men and 0.72 (0.64-0.85) for women. Our results imply that, in relatively egalitarian societies with state-supported access to higher education and political awareness of gender equality, genetic factors may play an important role in explaining sex differences in the relationship between education and income.
Edwards, Lorece V; Dennis, Sabriya; Weaks, Francesca
2013-09-01
Women's health encompasses a continuum of biological, psychological, and social challenges that differ considerably from those of men. Despite the remarkable advances in science, women's health and sex differences research is slowly gaining recognition and acceptance. It is important that women's health gain attention as women are usually the gatekeepers of care for the family. Women's health and health outcomes are strongly influenced by sex and gender differences as well as geography. Around the world, the interplay of biology and culture brings about differences in men's and women's health, which have been largely overlooked. The Women's Health: Increasing the Awareness of Science and Knowledge (WHISK) Pilot Project was a multidisciplinary project aimed to increase the awareness of sex and gender differences in women's health and research among healthcare professionals. Theater expression and creative art were used to translate knowledge, enhance understanding, and increase the awareness of sex differences. Findings from this project clearly showed an apparent increase in knowledge and cultivation of new insights.
Ahrenfeldt, Linda Juel; Larsen, Lisbeth Aagaard; Lindahl-Jacobsen, Rune; Skytthe, Axel; Hjelmborg, Jacob V B; Möller, Sören; Christensen, Kaare
2017-02-01
To investigate the twin testosterone transfer (TTT) hypothesis by comparing early-life mortality risks of opposite-sex (OS) and same-sex (SS) twins during the first 15 years of life. We performed a population-based cohort study to compare mortality in OS and SS twins. We included 68,629 live-born Danish twins from 1973 to 2009 identified through the Danish Twin Registry and performed piecewise stratified Cox regression and log-binomial regression. Among 1933 deaths, we found significantly higher mortality for twin boys than for twin girls. For both sexes, OS twins had lower mortality than SS twins; the difference persisted for the first year of life for boys and for the first week of life for girls. Although the mortality risk for OS boys was in the expected direction according to the TTT hypothesis, the results for OS girls pointed in the opposite direction, providing no clear evidence for the TTT hypothesis. Copyright © 2016 Elsevier Inc. All rights reserved.
Gotoh, Hiroki; Ishiguro, Mai; Nishikawa, Hideto; Morita, Shinichi; Okada, Kensuke; Miyatake, Takahisa; Yaginuma, Toshinobu; Niimi, Teruyuki
2016-01-01
Various types of weapon traits found in insect order Coleoptera are known as outstanding examples of sexually selected exaggerated characters. It is known that the sex determination gene doublesex (dsx) plays a significant role in sex-specific expression of weapon traits in various beetles belonging to the superfamily Scarabaeoidea. Although sex-specific weapon traits have evolved independently in various Coleopteran groups, developmental mechanisms of sex-specific expression have not been studied outside of the Scarabaeoidea. In order to test the hypothesis that dsx-dependent sex-specific expression of weapon traits is a general mechanism among the Coleoptera, we have characterized the dsx in the sexually dimorphic broad-horned beetle Gnatocerus cornutus (Tenebrionidea, Tenebirionidae). By using molecular cloning, we identified five splicing variants of Gnatocerus cornutus dsx (Gcdsx), which are predicted to code four different isoforms. We found one male-specific variant (GcDsx-M), two female-specific variants (GcDsx-FL and GcDsx-FS) and two non-sex-specific variants (correspond to a single isoform, GcDsx-C). Knockdown of all Dsx isoforms resulted in intersex phenotype both in male and female. Also, knockdown of all female-specific isoforms transformed females to intersex phenotype, while did not affect male phenotype. Our results clearly illustrate the important function of Gcdsx in determining sex-specific trait expression in both sexes. PMID:27404087
Feitelson, Dror G
2016-04-01
Cancer incidence and death statistics are typically recorded for multiple age and sex brackets, leading to large data tables which are difficult to digest. Effective visualizations of this data would allow practitioners, policy makers, and the general public to comprehend the data more readily and act on it appropriately. We introduce multilevel spie charts to create a combined visualization of cancer incidence and death statistics. Spie charts combine multiple pie charts, where the base pie chart (representing the general population) is used to set the angles of slices, and the superimposed ones use variable radii to portray the cancer data. Spie charts of cancer incidence and death statistics from Israel for 2009-2011 are used as an illustration. These charts clearly show various patterns of how cancer incidence and death distribute across age and sex groups, illustrating (1) absolute numbers and (2) rates per 100,000 population for different age and sex brackets. In addition, drawing separate charts for different cancer types illustrates relative mortality, both (3) across cancer types and (4) mortality relative to incidence. Naturally, this graphical depiction can be used for other diseases as well. Copyright © 2016 Elsevier Inc. All rights reserved.
Sex-typicality and attractiveness: are supermale and superfemale faces super-attractive?
Rhodes, G; Hickford, C; Jeffery, L
2000-02-01
Many animals find extreme versions of secondary sexual characteristics attractive, and such preferences can enhance reproductive success (Andersson, 1994). We hypothesized, therefore, that extreme versions of sex-typical traits may be attractive in human faces. We created supermale and superfemale faces by exaggerating all spatial differences between an average male and an average female face. In Expt 1 the male average was preferred to a supermale (50% exaggeration of differences from the female average). There was no clear preference for the female average or the superfemale (50% exaggeration). In Expt 2, participants chose the most attractive face from sets of images containing feminized as well as masculinized images for each sex, and spanning a wider range of exaggeration levels than in Expt 1. Chinese sets were also shown, to see whether similar preferences would occur for a less familiar race (participants were Caucasian). The most attractive female image was significantly feminized for faces of both races. However, the most attractive male image for both races was also significantly feminized. These results indicate that feminization, rather than sex exaggeration per se, is attractive in human faces, and they corroborate similar findings by Perrett et al. (1998).
Monéger, Françoise
2007-05-01
Most dioecious plant species are believed to derive from hermaphrodite ancestors. The regulatory pathways that have been modified during evolution of the hermaphrodite ancestors and led to the emergence of dioecious species (with separate sexes) still remain unknown. Silene latifolia is a dioecious plant species harbouring XY sex chromosomes. To identify the molecular mechanisms involved in female organ suppression in male flowers of S. latifolia, we looked for genes potentially involved in the establishment of floral organ and whorl boundaries. We identified Arabidopsis thaliana homologs of SHOOTMERISTEMLESS (STM) and CUP SHAPED COTYLEDON 1 (CUC1) and CUC2 genes in S. latifolia. Our phylogenetic analyses suggest that we identified true orthologs for both types of genes. Detailed expression analyses showed a conserved expression pattern for these genes between S. latifolia and A. thaliana, suggesting a conserved function of the corresponding proteins. Both orthologs showed clear differences in their expression pattern between males and females or hermaphrodites suggesting their possible involvement in the sex determination pathway in S. latifolia.
Women experience greater heat pain adaptation and habituation than men.
Hashmi, Javeria A; Davis, Karen D
2009-10-01
It is not clear how males and females cope with pain over time and how sensory and emotional qualities fluctuate from moment to moment, although studies of pain at discrete time points suggest that women are more pain sensitive than men. Therefore, we developed a new broader-based pain model that incorporates a temporally continuous assessment of multiple pain dimensions across sensory and affective dimensions, and normalized peak pain intensity to unmask sex differences that may otherwise be confounded by inter-individual variability in pain sensitivity. We obtained continuous ratings of pain, burning, sharp, stinging, cutting, and annoyance evoked by repeated prolonged noxious heat stimuli in 32 subjects. Strikingly, females reported more pain than males at the outset of the first exposure to pain, but then experienced less pain and annoyance than males as a painful stimulus was sustained and with repeated stimulation. Patterns of pain and annoyance attenuation in women resembled the attenuation of sharp, stinging and cutting sensations, whereas patterns of pain and annoyance in men resembled burning sensations. Taken together, these data demonstrate a prominent sex difference in the time course of pain. Notably only females demonstrate adaptation and habituation that allow them to experience less pain over time. These findings suggest a sexual dichotomy in mechanisms underlying pain intensity and annoyance that could involve specific quality-linked mechanisms. Importantly, temporal processing of pain differs between males and females when adjusted for sex differences in pain sensitivity. Our findings provide insight into sex differences in tonic and possibly chronic pains.
Myakotnykh, V S; Emelyanov, V V; Gavrilov, V I; Ermakova, E Y; Soloviev, R V; Borovkova, T A; Kutyreva, Y E; Berezina, D A; Torgashov, M N; Myakotnykh, K V
In the course of inspection 1136 persons of different age and sex data on dynamics of the main components of lipid profile, the concentration of brain-derived neurotrophic factor (BDNF) in blood plasma and indicators of levels of free cortisol, melatonin sulfate, metanephrine and normetanephrine in urine daily were obtained. Clear age and gender differences related both to the content of atherogenic fractions of lipids in the blood, and types of dyslipidemia were revealed. Fundamental differences in the age dynamics of indicators of stress-realizing systems in men and women and the correlation of these indicators with the level of low density lipoproteins and atherogenic coefficient were identified. The data obtained may indicate different mechanisms of development of atherosclerosis and its associated pathological aging in people of different sex and age, which enables the practical use of research results for the earliest diagnosis and prognosis of a number of associated with age and pathological conditions.
Sexual differences in food preferences in the white stork: an experimental study
NASA Astrophysics Data System (ADS)
Kwieciński, Zbigniew; Rosin, Zuzanna M.; Dylewski, Łukasz; Skórka, Piotr
2017-06-01
Sex differences in the foraging ecology of monomorphic species are poorly understood, due to problems with gender identification in field studies. In the current study, we used experimental conditions to investigate the food preferences of the white stork Ciconia ciconia, an opportunistic species in terms of food, but characterised by a low level of sexual dimorphism. During a 10-day experiment, 29 individuals (20 females and 9 males) were studied by means of a `cafeteria test' in which the storks' diet consisted of mammals, birds, fish, amphibians, insects and earthworms. The storks preferred food characterised by high calorific and protein values such as mammals, birds and fish. Sexes differed strongly in their preferences; males preferred mammals, whereas females preferred birds. Moreover, females consumed insects and earthworms less often than males. Interestingly, males spent significantly less time foraging than females. We have demonstrated that the white stork exhibits clear sexual differences in food preferences which are mostly attributable to differences in parental duties, physiology and anatomy.
ADHD and Female Specific Concerns: A Review of the Literature and Clinical Implications
ERIC Educational Resources Information Center
Nussbaum, Nancy L.
2012-01-01
ADHD was once thought of as a predominantly male disorder. While this may be true for ADHD in childhood, extant research suggests that the number of women with ADHD may be nearly equal to that of men with the disorder (Faraone et al., 2000). There is accumulating research which clearly indicates subtle but important sex differences exist in the…
1986-10-28
the prime minister nor have the franchise or stand as a candidate for an election. Under such circumstances, it is clear that there would be...politics in the country by ensuring them the equal franchise and eligibility for election, regardless of differences in sex, occupation, degree of property...for the lives of the people, takes complete responsibility for and guarantees all conditions needed for food , clothing and shelter. In our country
Intelligibility of clear speech: effect of instruction.
Lam, Jennifer; Tjaden, Kris
2013-10-01
The authors investigated how clear speech instructions influence sentence intelligibility. Twelve speakers produced sentences in habitual, clear, hearing impaired, and overenunciate conditions. Stimuli were amplitude normalized and mixed with multitalker babble for orthographic transcription by 40 listeners. The main analysis investigated percentage-correct intelligibility scores as a function of the 4 conditions and speaker sex. Additional analyses included listener response variability, individual speaker trends, and an alternate intelligibility measure: proportion of content words correct. Relative to the habitual condition, the overenunciate condition was associated with the greatest intelligibility benefit, followed by the hearing impaired and clear conditions. Ten speakers followed this trend. The results indicated different patterns of clear speech benefit for male and female speakers. Greater listener variability was observed for speakers with inherently low habitual intelligibility compared to speakers with inherently high habitual intelligibility. Stable proportions of content words were observed across conditions. Clear speech instructions affected the magnitude of the intelligibility benefit. The instruction to overenunciate may be most effective in clear speech training programs. The findings may help explain the range of clear speech intelligibility benefit previously reported. Listener variability analyses suggested the importance of obtaining multiple listener judgments of intelligibility, especially for speakers with inherently low habitual intelligibility.
Christenson, Robert H; Mullins, Kristin; Duh, Show-Hong
2018-06-01
High-Sensitivity (hs) cardiac troponin (cTn) assays are categorized by two criteria: (i) cTn values above the limit of detection (LoD) for >50% of male and female healthy cohorts of ≥300 individuals; (ii) imprecision ≤10% total %CV for sex-specific 99th-percentile clinical decision values (CDVs). No documented hs-Tn assay has yet been FDA-cleared. The PATHFAST cTnI-II assay's LoD was 2.3 ng/L using CLSI EP-17. The AACC Universal Sample Bank of 847 healthy men (50.6%) and women (49.4%) was used to determine 99th-percentile CDVs with Nonparametric, Harrell-Davis and Robust modeling. Health/Medication questionnaires and Amino-terminal proBNP, Hemoglobin A 1c and estimated Glomerular Filtration Rate surrogates excluded underlying health conditions. The cTnI-II test's total CV was 6.1% at 29 ng/L and 7.1% at 22 ng/L; the LoD was 2.3 ng/L. Of the full 847-member healthy cohort, 113 (13.3%) were excluded by abnormal surrogate biomarkers. The final 734-member healthy population had the following (% > LoD): overall, 487 (66.3%); women, 186 (52.8%); and men, 301 (78.8%). 99th-percentile CDVs by Nonparametric modeling were: 28 ng/L (90% CI: 20-30), overall final 732-member healthy population; 20 ng/L (90% CI: 13-30), 352 women; and 30 ng/L (90% CI: 21-37), 382 men. Differences between sex-specific CDVs were not significantly different (p > .05) with Nonparametric or Harrell-Davis modeling; however, Robust Modeling did show significance (<0.05), with lower CDVs at 11 ng/L (90% CI: 9-12) and 16 ng/L (90% CI: 15-18) for the female and male cohorts, respectively. cTnI-II is the only FDA-cleared assay that has demonstrated high-sensitivity cTn assay. Use of recommended modeling in >300 healthy subjects for determining sex-specific 99th-percentile CDVs did not show statistically significant differences except with the Robust modeling. Copyright © 2018. Published by Elsevier Inc.
Ono, Kim E; Burns, Thomas G; Bearden, Donald J; McManus, Susan M; King, Harold; Reisner, Andrew
2016-03-01
To date, few studies have delineated clear sex-based differences in symptom resolution after a sports-related concussion (SRC), and equivocal results have been identified in sex-based differences on baseline assessments. To assess whether female athletes displayed prolonged recovery and more symptoms at baseline and after an SRC compared with male athletes. Cohort study; Level of evidence, 3. The current study assessed 135 male and 41 female athletes (10-18 years old) who participated in high-impact sports in metropolitan Atlanta middle and high schools. All athletes completed a baseline assessment and at least 1 postconcussion assessment from the Immediate Post-Concussion Assessment and Cognitive Testing battery. Longitudinal hierarchical linear modeling was employed to examine individual-level variables and their associations with adolescents' rates of recovery in concussive symptoms after controlling for age and number of prior concussions. Aggregate symptoms were rated as higher in female athletes compared with male athletes at baseline (mean ± SD: females, 13.49 ± 11.20; males, 4.88 ± 8.74; F(1,175) = 10.59, P < .001) and immediately after a concussion (females: 16.75 ± 18.08; males: 10.58 ± 14.21; F(1,175) = 3.99, P = .05). There were no group differences in the slope of recovery between male and female athletes, indicating generally similar trajectories of change for both groups. Post hoc analyses revealed higher baseline levels of migraine and neuropsychological symptoms in female athletes. Although female athletes in the current study reported increased symptoms, identical recovery patterns were observed in both sexes, suggesting that sex-based differences in concussion recovery are better explained by increased symptom frequency among female athletes when compared with their male counterparts. © 2015 The Author(s).
The sexual dimorphism of obesity
Palmer, Biff F.; Clegg, Deborah J.
2015-01-01
The NIH has recently highlighted the importance of sexual dimorphisms and has mandated inclusion of both sexes in clinical trials and basic research. In this review we highlight new and novel ways sex hormones influence body adiposity and the metabolic syndrome. Understanding how and why metabolic processes differ by sex will enable clinicians to target and personalize therapies based on gender. Adipose tissue function and deposition differ by sex. Females differ with respect to distribution of adipose tissues, males tend to accrue more visceral fat, leading to the classic android body shape which has been highly correlated to increased cardiovascular risk; whereas females accrue more fat in the subcutaneous depot prior to menopause, a feature which affords protection from the negative consequences associated with obesity and the metabolic syndrome. After menopause, fat deposition and accrual shift to favor the visceral depot. This shift is accompanied by a parallel increase in metabolic risk reminiscent to that seen in men. A full understanding of the physiology behind why, and by what mechanisms, adipose tissues accumulate in specific depots and how these depots differ metabolically by sex is important in efforts of prevention of obesity and chronic disease. Estrogens, directly or through activation of their receptors on adipocytes and in adipose tissues, facilitate adipose tissue deposition and function. Evidence suggests that estrogens augment the sympathetic tone differentially to the adipose tissue depots favoring lipid accumulation in the subcutaneous depot in women and visceral fat deposition in men. At the level of adipocyte function, estrogens and their receptors influence the expandability of fat cells enhancing the expandability in the subcutaneous depot and inhibiting it in the visceral depot. Sex hormones clearly influence adipose tissue function and deposition, determining how to capture and utilize their function in a time of caloric surfeit, requires more information. The key will be harnessing the beneficial effects of sex hormones in such a way as to provide ‘healthy’ adiposity. PMID:25578600
Alvine, Travis; Rhen, Turk; Crossley, Dane A
2013-03-01
We investigated sex differences in cardiovascular maturation in embryos of the snapping turtle Chelydra serpentina, a species with temperature-dependent sex determination. One group of eggs was incubated at 26.5°C to produce males. Another group of eggs was incubated at 26.5°C until embryos reached stage 17; eggs were then shifted to 31°C for 6 days to produce females, and returned to 26.5°C for the rest of embryogenesis. Thus, males and females were at the same temperature when autonomic tone was determined and for most of development. Cholinergic blockade increased resting blood pressure (P(m)) and heart rate (f(H)) in both sexes at 75% and 90% of incubation. However, the magnitude of the f(H) response was enhanced in males compared with females at 90% of incubation. β-adrenergic blockade increased P(m) at 75% of incubation in both sexes but had no effect at 90% of incubation. β-adrenergic blockade reduced f(H) at both time points but produced a stronger response at 90% versus 75% of incubation. We found that α-adrenergic blockade decreased P(m) in both sexes at 75% and 90% of incubation and decreased f(H) at 75% of incubation in both sexes. At 90% of incubation, f(H) decreased in females but not males. Although these data clearly demonstrate sexual dimorphism in the autonomic regulation of cardiovascular physiology in embryos, further studies are needed to test whether differences are caused by endocrine signals from gonads or by a hormone-independent temperature effect.
Sex Education for Young Children with Special Needs.
ERIC Educational Resources Information Center
Clark, Edith Marie; Farley, Jack W.
1990-01-01
The article briefly reviews the research and controversy concerning sex education for handicapped children and offers five guidelines including build self-esteem, answer questions clearly and accurately, avoid threats and jokes, and respect children's privacy. (DB)
Schärer, Lukas; Pen, Ido
2013-03-05
Sex allocation theory predicts the optimal allocation to male and female reproduction in sexual organisms. In animals, most work on sex allocation has focused on species with separate sexes and our understanding of simultaneous hermaphrodites is patchier. Recent theory predicts that sex allocation in simultaneous hermaphrodites should strongly be affected by post-copulatory sexual selection, while the role of pre-copulatory sexual selection is much less clear. Here, we review sex allocation and sexual selection theory for simultaneous hermaphrodites, and identify several strong and potentially unwarranted assumptions. We then present a model that treats allocation to sexually selected traits as components of sex allocation and explore patterns of allocation when some of these assumptions are relaxed. For example, when investment into a male sexually selected trait leads to skews in sperm competition, causing local sperm competition, this is expected to lead to a reduced allocation to sperm production. We conclude that understanding the evolution of sex allocation in simultaneous hermaphrodites requires detailed knowledge of the different sexual selection processes and their relative importance. However, little is currently known quantitatively about sexual selection in simultaneous hermaphrodites, about what the underlying traits are, and about what drives and constrains their evolution. Future work should therefore aim at quantifying sexual selection and identifying the underlying traits along the pre- to post-copulatory axis.
Schärer, Lukas; Pen, Ido
2013-01-01
Sex allocation theory predicts the optimal allocation to male and female reproduction in sexual organisms. In animals, most work on sex allocation has focused on species with separate sexes and our understanding of simultaneous hermaphrodites is patchier. Recent theory predicts that sex allocation in simultaneous hermaphrodites should strongly be affected by post-copulatory sexual selection, while the role of pre-copulatory sexual selection is much less clear. Here, we review sex allocation and sexual selection theory for simultaneous hermaphrodites, and identify several strong and potentially unwarranted assumptions. We then present a model that treats allocation to sexually selected traits as components of sex allocation and explore patterns of allocation when some of these assumptions are relaxed. For example, when investment into a male sexually selected trait leads to skews in sperm competition, causing local sperm competition, this is expected to lead to a reduced allocation to sperm production. We conclude that understanding the evolution of sex allocation in simultaneous hermaphrodites requires detailed knowledge of the different sexual selection processes and their relative importance. However, little is currently known quantitatively about sexual selection in simultaneous hermaphrodites, about what the underlying traits are, and about what drives and constrains their evolution. Future work should therefore aim at quantifying sexual selection and identifying the underlying traits along the pre- to post-copulatory axis. PMID:23339243
Sexual Dimorphism in the Brain of the Monogamous California Mouse (Peromyscus californicus).
Campi, Katharine L; Jameson, Chelsea E; Trainor, Brian C
2013-01-01
Sex differences in behavior and morphology are usually assumed to be stronger in polygynous species compared to monogamous species. A few brain structures have been identified as sexually dimorphic in polygynous rodent species, but it is less clear whether these differences persist in monogamous species. California mice are among the 5% or less of mammals that are considered to be monogamous and as such provide an ideal model to examine sexual dimorphism in neuroanatomy. In the present study we compared the volume of hypothalamic- and limbic-associated regions in female and male California mice for sexual dimorphism. We also used tyrosine hydroxylase (TH) immunohistochemistry to compare the number of dopamine neurons in the ventral tegmental area (VTA) in female and male California mice. Additionally, tract tracing was used to accurately delineate the boundaries of the VTA. The total volume of the sexually dimorphic nucleus of the preoptic area (SDN-POA), the principal nucleus of the bed nucleus of the stria terminalis (BNST), and the posterodorsal medial amygdala (MEA) was larger in males compared to females. In the SDN-POA we found that the magnitude of sex differences in the California mouse were intermediate between the large differences observed in promiscuous meadow voles and rats and the absence of significant differences in monogamous prairie voles. However, the magnitude of sex differences in MEA and the BNST were comparable to polygynous species. No sex differences were observed in the volume of the whole brain, the VTA, the nucleus accumbens or the number of TH-ir neurons in the VTA. These data show that despite a monogamous social organization, sexual dimorphisms that have been reported in polygynous rodents extend to California mice. Our data suggest that sex differences in brain structures such as the SDN-POA persist across species with different social organizations and may be an evolutionarily conserved characteristic of mammalian brains.
2012-01-01
Background Calbindin-D28 has been used as a marker for the sexually dimorphic nucleus of the preoptic area (SDN-POA). Males have a distinct cluster of calbindin-immunoreactive (ir) cells in the medial preoptic area (CALB-SDN) that is reduced or absent in females. However, it is not clear whether the sex difference is due to the absolute number of calbindin-ir cells or to cell position (that is, spread), and the cellular mechanisms underlying the sex difference are not known. We examined the number of cells in the CALB-SDN and surrounding regions of C57Bl/6 mice and used mice lacking the pro-death gene, Bax, to test the hypothesis that observed sex differences are due to cell death. Methods Experiment 1 compared the number of cells in the CALB-SDN and surrounding regions in adult males, females, and females injected with estradiol benzoate on the day of birth. In experiment 2, cell number in the CALB-SDN and adjacent regions were compared in wild-type and Bax knockout mice of both sexes. In addition, calbindin-ir cells were quantified within the principal nucleus of the bed nucleus of the stria terminalis (BNSTp), a nearby region that is larger in males due to Bax-dependent cell death. Results Males had more cells in the CALB-SDN as well as in surrounding regions than did females, and estradiol treatment of females at birth masculinized both measures. Bax deletion had no effect on cell number in the CALB-SDN or surrounding regions but increased calbindin-ir cell number in the BNSTp. Conclusions The sex difference in the CALB-SDN of mice results from an estrogen-dependent difference in cell number with no evidence found for greater spread of cells in females. Blocking Bax-dependent cell death does not prevent sex differences in calbindin-ir cell number in the BNST or CALB-SDN but increases calbindin-ir cell number in the BNSTp of both sexes. PMID:22336348
Gilmore, Richard F; Varnum, Megan M; Forger, Nancy G
2012-02-15
Calbindin-D28 has been used as a marker for the sexually dimorphic nucleus of the preoptic area (SDN-POA). Males have a distinct cluster of calbindin-immunoreactive (ir) cells in the medial preoptic area (CALB-SDN) that is reduced or absent in females. However, it is not clear whether the sex difference is due to the absolute number of calbindin-ir cells or to cell position (that is, spread), and the cellular mechanisms underlying the sex difference are not known. We examined the number of cells in the CALB-SDN and surrounding regions of C57Bl/6 mice and used mice lacking the pro-death gene, Bax, to test the hypothesis that observed sex differences are due to cell death. Experiment 1 compared the number of cells in the CALB-SDN and surrounding regions in adult males, females, and females injected with estradiol benzoate on the day of birth. In experiment 2, cell number in the CALB-SDN and adjacent regions were compared in wild-type and Bax knockout mice of both sexes. In addition, calbindin-ir cells were quantified within the principal nucleus of the bed nucleus of the stria terminalis (BNSTp), a nearby region that is larger in males due to Bax-dependent cell death. Males had more cells in the CALB-SDN as well as in surrounding regions than did females, and estradiol treatment of females at birth masculinized both measures. Bax deletion had no effect on cell number in the CALB-SDN or surrounding regions but increased calbindin-ir cell number in the BNSTp. The sex difference in the CALB-SDN of mice results from an estrogen-dependent difference in cell number with no evidence found for greater spread of cells in females. Blocking Bax-dependent cell death does not prevent sex differences in calbindin-ir cell number in the BNST or CALB-SDN but increases calbindin-ir cell number in the BNSTp of both sexes.
Sexual selection protects against extinction.
Lumley, Alyson J; Michalczyk, Łukasz; Kitson, James J N; Spurgin, Lewis G; Morrison, Catriona A; Godwin, Joanne L; Dickinson, Matthew E; Martin, Oliver Y; Emerson, Brent C; Chapman, Tracey; Gage, Matthew J G
2015-06-25
Reproduction through sex carries substantial costs, mainly because only half of sexual adults produce offspring. It has been theorized that these costs could be countered if sex allows sexual selection to clear the universal fitness constraint of mutation load. Under sexual selection, competition between (usually) males and mate choice by (usually) females create important intraspecific filters for reproductive success, so that only a subset of males gains paternity. If reproductive success under sexual selection is dependent on individual condition, which is contingent to mutation load, then sexually selected filtering through 'genic capture' could offset the costs of sex because it provides genetic benefits to populations. Here we test this theory experimentally by comparing whether populations with histories of strong versus weak sexual selection purge mutation load and resist extinction differently. After evolving replicate populations of the flour beetle Tribolium castaneum for 6 to 7 years under conditions that differed solely in the strengths of sexual selection, we revealed mutation load using inbreeding. Lineages from populations that had previously experienced strong sexual selection were resilient to extinction and maintained fitness under inbreeding, with some families continuing to survive after 20 generations of sib × sib mating. By contrast, lineages derived from populations that experienced weak or non-existent sexual selection showed rapid fitness declines under inbreeding, and all were extinct after generation 10. Multiple mutations across the genome with individually small effects can be difficult to clear, yet sum to a significant fitness load; our findings reveal that sexual selection reduces this load, improving population viability in the face of genetic stress.
NASA Astrophysics Data System (ADS)
Robinson, W. P.; Gillibrand, E.
2004-06-01
The primary purpose was to investigate the efficacy of a full year of single-sex (SS) teaching of science. The secondary aims were to locate any differentiation by set and gender, and to relate these to more proximal variables. Participants were 13 year olds. Higher set girls gave evidence of clear benefits overall, and higher set boys also, except in biology. Lower set pupils performed at or below expectations. Analyses of additional questionnaire and interview data pointed to further reasons for avoiding the making of unqualified generalizations about SS teaching. Pupil preferences for SS teaching were relevant, as were gender differences in attitudes to biology and physics. Qualitative data suggested higher set girls benefited from more learningrelated classroom interaction and less interference and exploitation of girls by boys in SS classes. Lower set pupils complained that SS teaching deprived them of social interaction with the other sex. The concluding suggestion was that SS teaching offers affordances of benefits when mixed-sex teaching has specifiable disadvantages.
Goerlich-Jansson, Vivian C; Müller, Martina S; Groothuis, Ton G G
2013-12-01
Across various animal taxa not only the secondary sex ratio but also the primary sex ratio (at conception) shows significant deviations from the expected equal proportions of sons and daughters. Birds are especially intriguing to study this phenomenon as avian females are the heterogametic sex (ZW); therefore sex determination might be under direct control of the mother. Avian sex ratios vary in relation to environmental or maternal condition, which can also affect the production of maternal steroids that in turn are involved in reproduction and accumulate in the developing follicle before meiosis. As the proximate mechanisms underlying biased primary sex ratio are largely elusive, we explored how, and to what extent, maternal steroid hormones may be involved in affecting primary or secondary sex ratio in clutches of various species of pigeons. First we demonstrated a clear case of seasonal change in sex ratio in first eggs both in the Rock Pigeon (Columba livia) and in a related species, the Wood Pigeon (Columba palumbus), both producing clutches of two eggs. In the Homing Pigeon (Columba livia domestica), domesticated from the Rock Pigeon, testosterone treatment of breeding females induced a clear male bias, while corticosterone induced a female bias in first eggs and we argue that this is in line with sex allocation theory. We next analyzed treatment effects on follicle formation, yolk mass, and yolk hormones, the latter both pre- and post-ovulatory, in order to test a diversity of potential mechanisms related to both primary and secondary sex ratio manipulation. We conclude that maternal plasma hormone levels may affect several pre-ovulatory mechanisms affecting primary sex ratio, whereas egg hormones are probably involved in secondary sex ratio manipulation only.
Sex differences in interhemispheric communication during face identity encoding: evidence from ERPs.
Godard, Ornella; Leleu, Arnaud; Rebaï, Mohamed; Fiori, Nicole
2013-01-01
Sex-related hemispheric lateralization and interhemispheric transmission times (IHTTs) were examined in twenty-four participants at the level of the first visual ERP components (P1 and N170) during face identity encoding in a divided visual-field paradigm. While no lateralization-related and sex-related differences were reflected in the P1 characteristics, these two factors modulated the N170. Indeed, N170 amplitudes indicated a right hemisphere (RH) dominance in men (and a more bilateral functioning in women). N170 latencies and the derived IHTTs confirmed the RH advantage in men but showed the reverse asymmetry in women. Altogether, the results of this study suggest a clear asymmetry in men and a more divided work between the hemispheres in women, with a tendency toward a left hemisphere (LH) advantage. Thus, by extending the pattern to the right-sided face processing, our results generalize previous findings from studies using other materials and indicating longer transfers from the specialized to the non-specialized hemisphere, especially in the male brain. Because asymmetries started from the N170 component, the first electrophysiological index of high-level perceptual processing on face representations, they also suggest a functional account for hemispheric lateralization and sex-related differences rather than a structural one. Copyright © 2013 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.
Schmid, M; Feichtinger, W; Steinlein, C; Rupprecht, A; Haaf, T; Kaiser, H
2002-01-01
Highly differentiated, heteromorphic ZZ female symbol /ZW male symbol sex chromosomes were found in the karyotypes of the neotropical leptodactylid frogs Eleutherodactylus euphronides and E. shrevei. The W chromosomes are the largest heterochromatic, female-specific chromosomes so far discovered in the class Amphibia. The analyses of the banding patterns with AT- and GC base-pair specific fluorochromes show that the constitutive heterochromatin in the giant W chromosomes consists of various categories of repetitive DNA sequences. The W chromosomes of both species are similar in size, morphology and banding patterns, whereas their Z chromosomes exhibit conspicuous differences. In the cell nuclei of female animals, the W chromosomes form very prominent chromatin bodies (W chromatin). DNA flow cytometric measurements demonstrate clear differences in the DNA content of male and female erythrocytes caused by the giant W chromosome, and also shows that these Eleutherodactylus genomes are among the smallest of all amphibian genomes. The importance of the heteromorphic ZW sex chromosomes for the study of Z-linked genes, the similarities and differences of the two karyotypes, and the significance of the exceptionally small genomes are discussed. Copyright 2002 S. Karger AG, Basel
Molecular Identification of Sex in Phoenix dactylifera Using Inter Simple Sequence Repeat Markers.
Al-Ameri, Abdulhafed A; Al-Qurainy, Fahad; Gaafar, Abdel-Rhman Z; Khan, Salim; Nadeem, M
2016-01-01
Early sex identification of Date Palm (Phoenix dactylifera L.) at seedling stage is an economically desirable objective, which will significantly increase the profits of seed based cultivation. The utilization of molecular markers at this stage for early and rapid identification of sex is important due to the lack of morphological markers. In this study, a total of two hundred Inter Simple Sequence Repeat (ISSR) primers were screened among male and female Date palm plants to identify putative sex-specific marker, out of which only two primers (IS_A02 and IS_A71) were found to be associated with sex. The primer IS_A02 produced a unique band of size 390 bp and was found clearly in all female plants, while it was absent in all male plants. Contrary to this, the primer IS_A71 produced a unique band of size 380 bp and was clearly found in all male plants, whereas it was absent in all the female plants. Subsequently, these specific fragments were excised, purified, and sequenced for the development of sequence specific markers further in future for the implementation on dioecious Date Palm for sex determination. These markers are efficient, highly reliable, and reproducible for sex identification at the early stage of seedling.
Planning steps forward in development: in girls earlier than in boys.
Unterrainer, Josef M; Ruh, Nina; Loosli, Sandra V; Heinze, Katharina; Rahm, Benjamin; Kaller, Christoph P
2013-01-01
The development of planning ability in children initially aged four and five was examined longitudinally with a retest-interval of 12 months using the Tower of London task. As expected, problems to solve straightforward without mental look-ahead were mastered by most, even the youngest children. Problems demanding look-ahead were more difficult and accuracy improved significantly with age and over time. This development was strongly moderated by sex: In contrast to coeval boys, four year old girls showed an impressive performance enhancement at age five, reaching the performance of six year olds, whereas four year old boys lagged behind and caught up with girls at the age of six, the typical age of school enrollment. This sex-specific development of planning was clearly separated from overall intelligence: young boys showed a steeper increase in raw intelligence scores than girls, whereas in the older groups scores developed similarly. The observed sex differences in planning development are evident even within a narrow time window of twelve months and may relate to differences in maturational trajectories for girls and boys in dorsolateral prefrontal cortex.
Attitudes toward same-sex marriage: the case of Scandinavia.
Jakobsson, Niklas; Kotsadam, Andreas; Jakobsson, Siri Støre
2013-01-01
The purpose of this study was to examine the variables that explain attitudes toward same-sex marriage. Using recently collected Scandinavian data (from Norway and Sweden) with a high response rate, this study shows that gender, regular participation in religious activities, political ideology, education, whether the respondent lived in the capital city, and attitudes toward gender equality were important for attitudes toward same-sex marriage. Age and income were not important for attitudes toward same-sex marriage. Although both Norwegians and Swedes clearly favor same-sex marriage, Swedes are significantly more positive than Norwegians.
Latent class analysis on internet and smartphone addiction in college students.
Mok, Jung-Yeon; Choi, Sam-Wook; Kim, Dai-Jin; Choi, Jung-Seok; Lee, Jaewon; Ahn, Heejune; Choi, Eun-Jeung; Song, Won-Young
2014-01-01
This study aimed to classify distinct subgroups of people who use both smartphone and the internet based on addiction severity levels. Additionally, how the classified groups differed in terms of sex and psychosocial traits was examined. A total of 448 university students (178 males and 270 females) in Korea participated. The participants were given a set of questionnaires examining the severity of their internet and smartphone addictions, their mood, their anxiety, and their personality. Latent class analysis and ANOVA (analysis of variance) were the statistical methods used. Significant differences between males and females were found for most of the variables (all <0.05). Specifically, in terms of internet usage, males were more addicted than females (P<0.05); however, regarding smartphone, this pattern was reversed (P<0.001). Due to these observed differences, classifications of the subjects into subgroups based on internet and smartphone addiction were performed separately for each sex. Each sex showed clear patterns with the three-class model based on likelihood level of internet and smartphone addiction (P<0.001). A common trend for psychosocial trait factors was found for both sexes: anxiety levels and neurotic personality traits increased with addiction severity levels (all P<0.001). However, Lie dimension was inversely related to the addiction severity levels (all P<0.01). Through the latent classification process, this study identified three distinct internet and smartphone user groups in each sex. Moreover, psychosocial traits that differed in terms of addiction severity levels were also examined. It is expected that these results should aid the understanding of traits of internet and smartphone addiction and facilitate further study in this field.
Latent class analysis on internet and smartphone addiction in college students
Mok, Jung-Yeon; Choi, Sam-Wook; Kim, Dai-Jin; Choi, Jung-Seok; Lee, Jaewon; Ahn, Heejune; Choi, Eun-Jeung; Song, Won-Young
2014-01-01
Purpose This study aimed to classify distinct subgroups of people who use both smartphone and the internet based on addiction severity levels. Additionally, how the classified groups differed in terms of sex and psychosocial traits was examined. Methods A total of 448 university students (178 males and 270 females) in Korea participated. The participants were given a set of questionnaires examining the severity of their internet and smartphone addictions, their mood, their anxiety, and their personality. Latent class analysis and ANOVA (analysis of variance) were the statistical methods used. Results Significant differences between males and females were found for most of the variables (all <0.05). Specifically, in terms of internet usage, males were more addicted than females (P<0.05); however, regarding smartphone, this pattern was reversed (P<0.001). Due to these observed differences, classifications of the subjects into subgroups based on internet and smartphone addiction were performed separately for each sex. Each sex showed clear patterns with the three-class model based on likelihood level of internet and smartphone addiction (P<0.001). A common trend for psychosocial trait factors was found for both sexes: anxiety levels and neurotic personality traits increased with addiction severity levels (all P<0.001). However, Lie dimension was inversely related to the addiction severity levels (all P<0.01). Conclusion Through the latent classification process, this study identified three distinct internet and smartphone user groups in each sex. Moreover, psychosocial traits that differed in terms of addiction severity levels were also examined. It is expected that these results should aid the understanding of traits of internet and smartphone addiction and facilitate further study in this field. PMID:24899806
Estrogen Regulation of Duodenal Bicarbonate Secretion and Sex-Specific Protection of Human Duodenum
Tuo, Biguang; Wen, Guorong; Wei, Jinqi; Liu, Xuemei; Wang, Xue; Zhang, Yalin; Wu, Huichao; Dong, Xiao; Chow, Jimmy Y.C.; Vallon, Volker; Dong, Hui
2011-01-01
BACKGROUND & AIMS The reason that women have a lower prevalence of duodenal ulcer is not clear. We investigated whether estrogen regulates human duodenal bicarbonate secretion (DBS) and whether this process accounts for sex differences in the prevalence of duodenal ulcer. METHODS We performed an epidemiological study to correlate duodenal ulcer prevalence with sex and age. Proximal DBS was measured from healthy subjects. Estrogen receptor expression was examined in human duodenal mucosa by immunoblot and immunohistochemical analyses. RESULTS Among women, the prevalence of duodenal ulcer was significantly lower than among men. The reduced prevalence was greatest among premenopausal women (20–49 years), who were 3.91–5.09-fold less likely to develop duodenal ulcers than age-matched men; the difference was reduced to ≤1.32-fold among subjects 60 years or older. Premenopausal (20–29 years), but not post-menopausal (60–69 years) women, had significantly higher basal and acid-stimulated DBS than the age-matched men. Basal and acid-stimulated DBS in premenopausal women (20–29 years) were significantly higher than in post-menopausal women (60–69 years), whereas there were no significant differences in basal or acid-stimulated DBS between men that were 20–29 years old or 60–69 years old. Serum levels of estradiol changed in parallel with basal and acid-stimulated DBS during the physiological menstrual cycle in premenopausal women. 17β-estradiol-stimulated DBS was independent of age or sex. Estrogen receptors- and - were detected on plasma membrane and in cytosol of human duodenal epithelial cells. CONCLUSIONS Estrogen regulates human DBS, which could reduce the risk for duodenal ulcer in women and contribute to sex differences in prevalence of duodenal ulcer. PMID:21699784
Estrogen regulation of duodenal bicarbonate secretion and sex-specific protection of human duodenum.
Tuo, Biguang; Wen, Guorong; Wei, Jinqi; Liu, Xuemei; Wang, Xue; Zhang, Yalin; Wu, Huichao; Dong, Xiao; Chow, Jimmy Y C; Vallon, Volker; Dong, Hui
2011-09-01
The reason that women have a lower prevalence of duodenal ulcer is not clear. We investigated whether estrogen regulates human duodenal bicarbonate secretion (DBS) and whether this process accounts for sex differences in the prevalence of duodenal ulcer. We performed an epidemiologic study to correlate duodenal ulcer prevalence with sex and age. Proximal DBS was measured from healthy subjects. Estrogen-receptor expression was examined in human duodenal mucosa by immunoblot and immunohistochemical analyses. Among women, the prevalence of duodenal ulcer was significantly lower than among men. The reduced prevalence was greatest among premenopausal women (20-49 y), who were 3.91- to 5.09-fold less likely to develop duodenal ulcers than age-matched men; the difference was reduced to 1.32-fold or less among subjects aged 60 years or older. Premenopausal (20-29 y), but not postmenopausal (60-69 y), women had significantly higher basal and acid-stimulated DBS than the age-matched men. Basal and acid-stimulated DBS in premenopausal women (20-29 y) were significantly higher than in postmenopausal women (60-69 y), whereas there were no significant differences in basal or acid-stimulated DBS between men who were aged 20-29 years or 60-69 years. Serum levels of estradiol changed in parallel with basal and acid-stimulated DBS during the physiological menstrual cycle in premenopausal women. 17β-estradiol-stimulated DBS was independent of age or sex. Estrogen receptors α and β were detected on plasma membranes and in the cytosol of human duodenal epithelial cells. Estrogen regulates human DBS, which could reduce the risk for duodenal ulcer in women and contribute to sex differences in the prevalence of duodenal ulcer. Copyright © 2011 AGA Institute. Published by Elsevier Inc. All rights reserved.
Steinke, S; Bruland, P; Blome, C; Osada, N; Dugas, M; Fritz, F; Augustin, M; Ständer, S
2017-02-01
Chronic pruritus (CP) is present in approximately one-third of all dermatological patients. Diagnostics and treatment are challenging and impair patients' quality of life. To analyse therapeutic needs in terms of the importance of treatment goals in a large sample of patients with CP. Routine data of 2747 patients with CP were analysed with descriptive methods and significance tests (univariate and multivariate variance analyses). The importance of 27 need items was measured using the Patient Needs Questionnaire of the Patient Benefit Index. The most important needs were to find a clear diagnosis and treatment, to no longer experience itching and to have confidence in the therapy, which were quite or very important to > 90% of the patients. The least important goals concerned a normal working or sex life. Nine needs related mostly to disease and psychological symptoms, and some social needs differed in importance between sexes (P ≤ 0·05). Patients with pruritus on inflamed skin or with chronic scratch lesions judged more than half of all needs as more important than did patients with pruritus on noninflamed skin (P ≤ 0·05). In the multivariate model, age, pruritus intensity and quality of life had a significant effect on the importance of therapeutic needs besides sex and pruritus classification. Patients with CP present high levels of various therapeutic needs with differences by sex and clinical phenotype. The most important needs can be addressed through medical activities such as appropriate itch medication and a trustful doctor-patient relationship. © 2016 British Association of Dermatologists.
Willacker, James J.; Von Hippel, Frank A.; Ackerly, Kerri L.; O’Hara, Todd M.
2013-01-01
Mercury (Hg) is a widespread environmental contaminant known for the neurotoxicity of its methylated forms, especially monomethylmercury, which bioaccumulates and biomagnifies in aquatic food webs. Mercury bioaccumulation and biomagnification rates are known to vary among species utilizing different food webs (benthic vs limnetic) within and between systems. The authors assessed whether carbon and nitrogen stable isotope values and total Hg (THg) concentrations differed between sympatric benthic and limnetic ecotypes and sexes of threespine stickleback fish (Gasterosteus aculeatus) from Benka Lake, Alaska, USA. The mean THg concentration in the limnetic ecotype was significantly higher (26 mg/kg dry wt, 16.1%) than that of the benthic ecotype. Trophic position and benthic carbon percentage utilized were both important determinants of THg concentration; however, the 2 variables were of approximately equal importance in females, whereas trophic position clearly explained more of the variance than benthic carbon percentage in males. Additionally, strong sex effects (45 mg/kg dry wt, 29.4%) were observed in both ecotypes, with female fish having lower THg concentrations than males. These results indicate that trophic ecology and sex are both important determinants of Hg contamination even within a single species and lake and likely play a role in governing Hg concentrations in higher trophic levels. PMID:23456641
Ospina-Alvarez, Natalia; Piferrer, Francesc
2008-07-30
In gonochoristic vertebrates, sex determination mechanisms can be classified as genotypic (GSD) or temperature-dependent (TSD). Some cases of TSD in fish have been questioned, but the prevalent view is that TSD is very common in this group of animals, with three different response patterns to temperature. We analyzed field and laboratory data for the 59 fish species where TSD has been explicitly or implicitly claimed so far. For each species, we compiled data on the presence or absence of sex chromosomes and determined if the sex ratio response was obtained within temperatures that the species experiences in the wild. If so, we studied whether this response was statistically significant. We found evidence that many cases of observed sex ratio shifts in response to temperature reveal thermal alterations of an otherwise predominately GSD mechanism rather than the presence of TSD. We also show that in those fish species that actually have TSD, sex ratio response to increasing temperatures invariably results in highly male-biased sex ratios, and that even small changes of just 1-2 degrees C can significantly alter the sex ratio from 1:1 (males:females) up to 3:1 in both freshwater and marine species. We demonstrate that TSD in fish is far less widespread than currently believed, suggesting that TSD is clearly the exception in fish sex determination. Further, species with TSD exhibit only one general sex ratio response pattern to temperature. However, the viability of some fish populations with TSD can be compromised through alterations in their sex ratios as a response to temperature fluctuations of the magnitude predicted by climate change.
Patterns and rates of viral evolution in HIV-1 subtype B infected females and males.
Dapp, Michael J; Kober, Kord M; Chen, Lennie; Westfall, Dylan H; Wong, Kim; Zhao, Hong; Hall, Breana M; Deng, Wenjie; Sibley, Thomas; Ghorai, Suvankar; Kim, Katie; Chen, Natalie; McHugh, Sarah; Au, Lily; Cohen, Mardge; Anastos, Kathryn; Mullins, James I
2017-01-01
Biological sex differences affect the course of HIV infection, with untreated women having lower viral loads compared to their male counterparts but, for a given viral load, women have a higher rate of progression to AIDS. However, the vast majority of data on viral evolution, a process that is clearly impacted by host immunity and could be impacted by sex differences, has been derived from men. We conducted an intensive analysis of HIV-1 gag and env-gp120 evolution taken over the first 6-11 years of infection from 8 Women's Interagency HIV Study (WIHS) participants who had not received combination antiretroviral therapy (ART). This was compared to similar data previously collected from men, with both groups infected with HIV-1 subtype B. Early virus populations in men and women were generally homogenous with no differences in diversity between sexes. No differences in ensuing nucleotide substitution rates were found between the female and male cohorts studied herein. As previously reported for men, time to peak diversity in env-gp120 in women was positively associated with time to CD4+ cell count below 200 (P = 0.017), and the number of predicted N-linked glycosylation sites generally increased over time, followed by a plateau or decline, with the majority of changes localized to the V1-V2 region. These findings strongly suggest that the sex differences in HIV-1 disease progression attributed to immune system composition and sensitivities are not revealed by, nor do they impact, global patterns of viral evolution, the latter of which proceeds similarly in women and men.
Valdivia, Karina; Jouanno, Elodie; Volff, Jean-Nicolas; Galiana-Arnoux, Delphine; Guyomard, René; Helary, Louise; Mourot, Brigitte; Fostier, Alexis; Quillet, Edwige; Guiguen, Yann
2014-01-01
Salmonids are generally considered to have a robust genetic sex determination system with a simple male heterogamety (XX/XY). However, spontaneous masculinization of XX females has been found in a rainbow trout population of gynogenetic doubled haploid individuals. The analysis of this masculinization phenotype transmission supported the hypothesis of the involvement of a recessive mutation (termed mal). As temperature effect on sex differentiation has been reported in some salmonid species, in this study we investigated in detail the potential implication of temperature on masculinization in this XX mal-carrying population. Seven families issued from XX mal-carrying parents were exposed from the time of hatching to different rearing water temperatures ((8, 12 and 18°C), and the resulting sex-ratios were confirmed by histological analysis of both gonads. Our results demonstrate that masculinization rates are strongly increased (up to nearly two fold) at the highest temperature treatment (18°C). Interestingly, we also found clear differences between temperatures on the masculinization of the left versus the right gonads with the right gonad consistently more often masculinized than the left one at lower temperatures (8 and 12°C). However, the masculinization rate is also strongly dependent on the genetic background of the XX mal-carrying families. Thus, masculinization in XX mal-carrying rainbow trout is potentially triggered by an interaction between the temperature treatment and a complex genetic background potentially involving some part of the genetic sex differentiation regulatory cascade along with some minor sex-influencing loci. These results indicate that despite its rather strict genetic sex determinism system, rainbow trout sex differentiation can be modulated by temperature, as described in many other fish species.
Valdivia, Karina; Jouanno, Elodie; Volff, Jean-Nicolas; Galiana-Arnoux, Delphine; Guyomard, René; Helary, Louise; Mourot, Brigitte; Fostier, Alexis; Quillet, Edwige; Guiguen, Yann
2014-01-01
Salmonids are generally considered to have a robust genetic sex determination system with a simple male heterogamety (XX/XY). However, spontaneous masculinization of XX females has been found in a rainbow trout population of gynogenetic doubled haploid individuals. The analysis of this masculinization phenotype transmission supported the hypothesis of the involvement of a recessive mutation (termed mal). As temperature effect on sex differentiation has been reported in some salmonid species, in this study we investigated in detail the potential implication of temperature on masculinization in this XX mal-carrying population. Seven families issued from XX mal-carrying parents were exposed from the time of hatching to different rearing water temperatures ((8, 12 and 18°C), and the resulting sex-ratios were confirmed by histological analysis of both gonads. Our results demonstrate that masculinization rates are strongly increased (up to nearly two fold) at the highest temperature treatment (18°C). Interestingly, we also found clear differences between temperatures on the masculinization of the left versus the right gonads with the right gonad consistently more often masculinized than the left one at lower temperatures (8 and 12°C). However, the masculinization rate is also strongly dependent on the genetic background of the XX mal-carrying families. Thus, masculinization in XX mal-carrying rainbow trout is potentially triggered by an interaction between the temperature treatment and a complex genetic background potentially involving some part of the genetic sex differentiation regulatory cascade along with some minor sex-influencing loci. These results indicate that despite its rather strict genetic sex determinism system, rainbow trout sex differentiation can be modulated by temperature, as described in many other fish species. PMID:25501353
Sex differences in olfactory-induced neural activation of the amygdala.
Kikusui, Takefumi; Kajita, Mayu; Otsuka, Natsumi; Hattori, Tatsuya; Kumazawa, Kanako; Watarai, Akiyuki; Nagasawa, Miho; Inutsuka, Ayumu; Yamanaka, Akihiro; Matsuo, Naoki; Covington, Herbert E; Mogi, Kazutaka
2018-07-02
Olfactory signals, including the scent of urine, are thought to be processed by specific brain regions, such as the medial amygdala (Me), and regulate sexual behavior in a sex-dependent manner. We aimed to reveal the sex-specific neural circuit from the accessory olfactory bulb (AOB) to Me by using a transgenic mouse. We quantified the long-lasting green fluorescent protein (GFP) expression profile, which was controlled by the c-fos promotor in a sex-dependent manner by the scent of urine. Female urine predominantly activated neurons of the posterodorsal medial amygdala (MePD) in male mice and the posteroventral medial amygdala (MePV) in female mice. Male urine, in contrast, generated the opposite pattern of activation in the Me. Secondary, the selective artificial activation of these circuits was used to examine their specific behavioral function, by using a dual Cre-loxP viral infection. AAV-hSyn-FLEX-hM3Dq-EGFP-the designer receptor exclusively activated by a designer drug-was infused into the AOB after infection with trans-synaptic AAV(DJ)-CMV-mCherry-2A-Cre-TTC into either the MePD or the MePV. Double virus-transfected mice were injected with hM 3 Dq activator and their sexual behavior was monitored. However, selective activation of sex-dependent circuits, i.e., the AOB-MePD or AOB-MePV, did not significantly alter mounting or attack behavior in male mice. There were clear sex differences in the pheromone conveying circuits in the AOB-Me of mice. The sex-dependent functional activation of the Me, however, no effect on behavior. This suggests that a diverse number of nuclei and brain areas are likely to function in concert to successfully facilitate sexual and aggressive behaviors. Copyright © 2017 Elsevier B.V. All rights reserved.
Morinha, Francisco; Travassos, Paulo; Seixas, Fernanda; Santos, Nuno; Sargo, Roberto; Sousa, Luís; Magalhães, Paula; Cabral, João A; Bastos, Estela
2013-05-01
High-resolution melting (HRM) analysis is a very attractive and flexible advanced post-PCR method with high sensitivity/specificity for simple, fast and cost-effective genotyping based on the detection of specific melting profiles of PCR products. Next generation real-time PCR systems, along with improved saturating DNA-binding dyes, enable the direct acquisition of HRM data after quantitative PCR. Melting behaviour is particularly influenced by the length, nucleotide sequence and GC content of the amplicons. This method is expanding rapidly in several research areas such as human genetics, reproductive biology, microbiology and ecology/conservation of wild populations. Here we have developed a successful HRM protocol for avian sex identification based on the amplification of sex-specific CHD1 fragments. The melting curve patterns allowed efficient sexual differentiation of 111 samples analysed (plucked feathers, muscle tissues, blood and oral cavity epithelial cells) of 14 bird species. In addition, we sequenced the amplified regions of the CHD1 gene and demonstrated the usefulness of this strategy for the genotype discrimination of various amplicons (CHD1Z and CHD1W), which have small size differences, ranging from 2 bp to 44 bp. The established methodology clearly revealed the advantages (e.g. closed-tube system, high sensitivity and rapidity) of a simple HRM assay for accurate sex differentiation of the species under study. The requirements, strengths and limitations of the method are addressed to provide a simple guide for its application in the field of molecular sexing of birds. The high sensitivity and resolution relative to previous real-time PCR methods makes HRM analysis an excellent approach for improving advanced molecular methods for bird sexing. © 2013 Blackwell Publishing Ltd.
Pierman, Sylvie; Douhard, Quentin; Balthazart, Jacques; Baum, Michael J; Bakker, Julie
2006-01-01
We previously found that both male and female aromatase knockout (ArKO) mice, which cannot synthesize estrogens due to a targeted mutation of the aromatase gene, showed less investigation of volatile body odors from anesthetized conspecifics of both sexes in Y-maze tests. We now ask whether ArKO mice are in fact capable of discriminating between and/or responding to volatile odors. Using habituation/dishabituation tests, we found that gonadectomized ArKO and wild-type (WT) mice of both sexes, which were tested without any sex hormone replacement, reliably distinguished between undiluted volatile urinary odors of either adult males or estrous females versus deionized water as well as between these two urinary odors themselves. However, ArKO mice of both sexes were less motivated than WT controls to investigate same-sex odors when they were presented last in the sequence of stimuli. In a second experiment, we compared the ability of ArKO and WT mice to respond to decreasing concentrations of either male or female urinary odors. We found a clear-cut sex difference in urinary odor attraction thresholds among WT mice: WT males failed to respond to urine dilutions higher than 1:20 by volume, whereas WT females continued to respond to urine dilutions up to 1:80. Male ArKO mice resembled WT females in their ability to respond to lower concentrations of urinary odors, raising the possibility that the observed sex difference among WT mice in urine attraction thresholds results from the perinatal actions of estrogen in the male nervous system. Female ArKO mice failed to show significant dishabituation responses to two (1:20 and 1:80) dilutions of female urine, perhaps, again, because of a reduced motivation to investigate less salient, same-sex urinary odors. Previously observed deficits in the preference of ArKO male and female mice to approach volatile body odors from conspecifics of either sex cannot be attributed to an inability of ArKO subjects to discriminate these odors according to sex but instead may reflect a deficient motivation to approach same-sex odors, especially when their concentration is low.
Sex differences in razorbill (Family: Alcidae) parent-offspring vocal recognition
NASA Astrophysics Data System (ADS)
Insley, Stephen J.; Paredes Vela, Rosana; Jones, Ian L.
2002-05-01
In this study we examines how a pattern of parental care may result in a sex bias in vocal recognition. In Razorbills (Alca torda), both sexes provide parental care to their chicks while at the nest, after which the male is the sole caregiver for an additional period at sea. Selection pressure acting on recognition behavior is expected to be strongest during the time when males and chicks are together at sea, and as a result, parent-offspring recognition was predicted to be better developed in the male parent, that is, show a paternal bias. In order to test this hypothesis, vocal playback experiments were conducted on breeding Razorbills at the Gannet Islands, Labrador, 2001. The data provide clear evidence of mutual vocal recognition between the male parent and chick but not between the female parent and chick, supporting the hypothesis that parent-offspring recognition is male biased in this species. In addition to acoustic recognition, such a bias could have important social implications for a variety of behavioral and basic life history traits such as cooperation and sex-biased dispersal.
Iurin, A G
2010-01-01
Non-metastatic clear-cell renal cancer: dependence of the tumour stage on clinico-anatomic and morphologic factors; prognostic value of macro- and karyometric characteristics Sankt Peterburg Pathology Bureau, Sankt Peterburg It was shown based on multivariate regression analysis that pT1a3bN0MO stages of non-metastatic clear-cell renal cancer significantly correlate not only with the tumor size and invasion into the fatty tissue and/or renal vein but also with the invasion into the renal capsule and with the mean maximum diameter and mean nucleus area of tumor cells. There was no correlation of clear-cell renal cancer stages with tumor proliferative activity, gene p53 mutation, oncosuppressor gene PTEN expression, fraction of tumour clear-cell component, and such clinical characteristics as patients' sex, age, and body mass index. Taking into account statistically significant differences between the patients' survival rates, the regression equations developed in this work may be used for the prediction of disease outcome.
Yoshido, A; Marec, F; Sahara, K
2016-01-01
Moths and butterflies (Lepidoptera) have sex chromosome systems with female heterogamety (WZ/ZZ or derived variants). The maternally inherited W chromosome is known to determine female sex in the silkworm, Bombyx mori. However, little is known about the role of W chromosome in other lepidopteran species. Here we describe two forms of the W chromosome, W and neo-W, that are transmitted to both sexes in offspring of hybrids from reciprocal crosses between subspecies of wild silkmoths, Samia cynthia. We performed crosses between S. c. pryeri (2n=28, WZ/ZZ) and S. c. walkeri (2n=26, neo-Wneo-Z/neo-Zneo-Z) and examined fitness and sex chromosome constitution in their hybrids. The F1 hybrids of both reciprocal crosses had reduced fertility. Fluorescence in situ hybridization revealed not only the expected sex chromosome constitutions in the backcross and F2 hybrids of both sexes but also females without the W (or neo-W) chromosome and males carrying the W (or neo-W) chromosome. Furthermore, crosses between the F2 hybrids revealed no association between the presence or absence of W (or neo-W) chromosome and variations in the hatchability of their eggs. Our results clearly suggest that the W (or neo-W) chromosome of S. cynthia ssp. plays no role in sex determination and reproduction, and thus does not contribute to the formation of reproductive barriers between different subspecies. PMID:26758188
Yoshido, A; Marec, F; Sahara, K
2016-05-01
Moths and butterflies (Lepidoptera) have sex chromosome systems with female heterogamety (WZ/ZZ or derived variants). The maternally inherited W chromosome is known to determine female sex in the silkworm, Bombyx mori. However, little is known about the role of W chromosome in other lepidopteran species. Here we describe two forms of the W chromosome, W and neo-W, that are transmitted to both sexes in offspring of hybrids from reciprocal crosses between subspecies of wild silkmoths, Samia cynthia. We performed crosses between S. c. pryeri (2n=28, WZ/ZZ) and S. c. walkeri (2n=26, neo-Wneo-Z/neo-Zneo-Z) and examined fitness and sex chromosome constitution in their hybrids. The F1 hybrids of both reciprocal crosses had reduced fertility. Fluorescence in situ hybridization revealed not only the expected sex chromosome constitutions in the backcross and F2 hybrids of both sexes but also females without the W (or neo-W) chromosome and males carrying the W (or neo-W) chromosome. Furthermore, crosses between the F2 hybrids revealed no association between the presence or absence of W (or neo-W) chromosome and variations in the hatchability of their eggs. Our results clearly suggest that the W (or neo-W) chromosome of S. cynthia ssp. plays no role in sex determination and reproduction, and thus does not contribute to the formation of reproductive barriers between different subspecies.
Local estrogenic/androgenic balance in the cerebral vasculature
Krause, Diana N.; Duckles, Sue P.; Gonzales, Rayna J.
2011-01-01
Reproductive effects of sex steroids are well-known, however it is increasingly apparent that these hormones have important actions on non-reproductive tissues such as the vasculature. The latter effects can be relevant throughout the lifespan, not just limited to reproductive years, and are not necessarily restricted to one sex or the other. Our work has established that cerebral blood vessels are a non-reproductive target tissue for sex steroids. We have found that estrogen and androgens alter vascular tone, endothelial function, oxidative stress and inflammatory responses in cerebral vessels. Often the actions of estrogen and androgens oppose each other. Moreover, it is clear that cerebral vessels are directly targeted by sex steroids as they express specific receptors for these hormones. Interestingly, cerebral blood vessels also express enzymes that metabolize sex steroids. These findings suggest that local synthesis of 17β-estradiol and dihydrotestosterone can occur within the vessel wall. One of the enzymes present, aromatase, converts testosterone to 17β-estradiol, which would alter the local balance of androgenic and estrogenic influences. Thus cerebral vessels are affected by circulating sex hormones as well as locally synthesized sex steroids. The presence of vascular endocrine effector mechanisms has important implications for male-female differences in cerebrovascular function and disease. Moreover, the cerebral circulation is a target for gonadal hormones as well as anabolic steroids and therapeutic drugs used to manipulate sex steroid actions. The long-term consequences of these influences have yet to be determined. PMID:21535417
Sex Differences in Patient-Reported Poststroke Disability.
White, Brandi M; Magwood, Gayenell S; Burns, Suzanne Perea; Ellis, Charles
2018-04-01
Recent studies have shown that stroke has a differential impact in women compared to men. Women are more likely to survive strokes than men, yet they experience more severe strokes resulting in greater poststroke disability. However, few studies have characterized sex differences in functional ability after stroke. This study examined sex differences in long-term disability among stroke survivors. This was a retrospective analysis of the 2015 National Health Interview Survey. Respondents were asked to rate their ability to perform 11 functional tasks. Univariate comparisons were completed to evaluate sex differences in performance, and multinomial logistic regression was used to determine the odds of reporting functional limitations. Five hundred fourteen men and 641 women stroke survivors completed the survey (mean age: 66.9 years). Approximately 75% of the sample reported having hypertension, 61% high cholesterol, 33% diabetes, 24% heart disease, 21% heart attack, and 16% chronic obstructive pulmonary disease. In the predictive models, men were less likely to report "very difficult/can't do at all" in walking ¼ mile (odds ratios [OR] = 0.68, 95% CI 0.51-0.90), climbing 10 steps (OR = 0.65, 95% CI 0.49-0.85), standing 2 hours (OR = 0.66, 95% CI 0.50-0.87), stooping (OR = 0.51, 95% CI 0.39-0.68), reaching overhead (OR = 0.69, 95% CI 0.49-0.97), carrying 10 pounds (OR = 0.45, 95% CI 0.34-0.59), and pushing large objects (OR = 0.37, 95% CI 0.28-0.5) compared to women. The functional outcomes of men stroke survivors were significantly greater than women. The specific factors that contribute to sex differences in stroke-related outcomes are not entirely clear. Future research is needed to better understand these differences to ensure that equity of care is received.
Gender differences in endocrine responses to posture and 7 days of 6 deg head down bed rest
NASA Technical Reports Server (NTRS)
Vernikos, J.; Dallman, M. F.; Keil, L. C.; Ohara, D.; Convertino, V. A.
1993-01-01
Endocrine regulation of fluids and electrolytes during seven days of 6 deg head down bed rest (HDBR) was compared in male (n = 8) and, for the first time, female (n = 8) volunteers. The subjects' responses to quiet standing for 2 hr before and after HDBR were also tested. In both sexes, diuresis and natriuresis were evident during the first 2-3 days of HDBR, resulting in a marked increase in the urinary Na/K ratio and significant Na retention on reambulation. After the first day of HDBR, plasma renin activity (PRA) was increased relative to aldosterone, plasma volume was decreased, and the renal response to aldosterone appeared to be appropriate. Circulating levels of arginine vasopressin (AVP), cortisol, and ACTH were unchanged during HDBR. Plasma testosterone decreased slightly on day 2 of HDBR in males. The ratio of AM ACTH to cortisol was lower in females than in males because ACTH was lower in females. Urinary cortisol increased and remained elevated throughout the HDBR in males only. There were no gender differences in the responses to 7 day HDBR, except those in the pituitary-adrenal system; those differences appeared unrelated to the postural change. The provocative cardiovascular test of quiet standing before and after bed rest revealed both sex differences and effects of HDBR. There were significant sex differences in cardiovascular responses to standing, before and after HDBR. Females had greater PRA and aldosterone responses to standing before bedrest and larger aldosterone responses to standing after HDBR than males. Cardiovascular responses to standing before and after bedrest differed markedly: arterial pressure and heart rates increased with standing before HDBR, by contrast, arterial pressure decreased, with greater increases in heart rates after HDBR. In both sexes, all hormonal responses to standing were greater after HDBR. The results show clearly that similar responses to standing as well as to HDBR occur in both sexes, but that females exhibit greater PRA and aldosterone responses than males.
Exploring attentional biases towards facial expressions of pain in men and women.
Keogh, E; Cheng, F; Wang, S
2018-05-14
Interpersonal factors may help explain why men and women differ in their perception and expression of pain. Whilst the focus is often on the person in pain, how observers respond to those in pain is important. This study explored whether male-female differences exist in the way observers attend to expressions of pain in others. Fifty-three adults (26 females) completed a visual dot-probe task, to measure selective attentional biases to facial expressions of pain and fear. Expression pairs (e.g. pain/neutral) were displayed by either the same male or female actor, and in two different viewing duration conditions: 150 and 1250 ms. Dot-probes appeared in either a congruent or incongruent location to the target expression. No evidence was found for sex-related attentional biases towards pain or fear. However, when examining congruency and incongruency indexes separately, differences emerged. The congruency index analysis indicated that in the 150-ms presentation condition, both men and women were slower during congruent female pain/neutral trials when compared to neutral/neutral trials, and relatively faster at responding during congruent male pain/neutral trials. There is utility in exploring the attentional processes involved in the decoding of pain-related expressions to understand the influence of sex and gender differences in pain. Although male-female differences were found, this was most clearly related to the actor. Our results point to an early attentional mechanism that orients attention away from female expressions of pain. Future consideration of sex- and gender-related contextual factors in attentional processing is warranted. Sex-related factors seem to affect how observers view the pain of others. Our results point to an early attentional mechanism that orients the attention of observers away from female expressions of pain. © 2018 European Pain Federation - EFIC®.
Do women fare worse? A metaanalysis of gender differences in outcome after traumatic brain injury.
Farace, E; Alves, W M
2000-01-01
The purpose of this metaanalysis was to investigate possible gender differences in TBI sequelae. The case fatality rates in patients after TBI have previously been shown to be significantly higher in women as compared with men. A quantitative review of published studies of TBI outcome revealed eight studies (20 outcome variables) of TBI in which outcome was reported separately for men and women. Outcome was worse in women than in men for 85% of the measured variables, with an average effect size of -0.15. Although clinical opinion is often that women tend to experience better outcomes than do men after TBI, the opposite pattern was suggested in the results of this metaanalysis. However, this conclusion is limited by the fact that in only a small percentage of the total published reports on TBI outcome was outcome described separately for each sex. A careful, prospective study of sex differences in TBI outcome is clearly needed.
Managing Codling Moth Clearly and Precisely with Semiochemicals
USDA-ARS?s Scientific Manuscript database
Site-specific management practices for codling moth were implemented in ‘Comice’ pear orchards treated with aerosol puffers releasing sex pheromone in southern Oregon during 2008 and 2009. The density of monitoring traps baited with sex pheromone and pear ester was increased and insecticide sprays w...
Verma, Sushant Kumar; Alim, Abdul
2015-05-01
The present study was carried out to analyze the differences in the activity of ultimobranchial gland (UBG) between male and female fresh water teleost Mastacembelus armatus during reproductive cycle. Considerable variations in the nuclear diameter of UBG cells and plasma calcitonin (CT) levels during different reproductive phases of testicular and ovarian cycle suggested that the activity of the UBG depends upon the sexual maturity of fishes. A positive correlation was observed between plasma CT and sex steroid levels and the gonadosomatic index in both sexes which further confirmed the involvement of UBG in the processes related to gonadal development in fishes irrespective of the sex. Sudden increase in the level of plasma CT and nuclear diameter of UBG cells after administration of 17 α-methyltestosterone in males and 17 β-estradiol in females during resting phase of the reproductive cycle clearly showed that UBG becomes hyperactive with increases in the level of sex steroids. Plasma calcium level was also found to be positively correlated with gonadal maturation in females. However no such change in plasma calcium level in relation to testicular cycle was observed. Thus it can be concluded that UBG becomes hyperactive during gonadal maturation but its role differs between male and female fishes. In females it may involved in both gonadal maturation and plasma calcium regulation while in males its involvement in calcium regulation was not justified. Variations in the level of CT during various phases of testicular cycle evidenced its involvement in gonadal maturation only. Copyright © 2015 Elsevier B.V. All rights reserved.
Gender differences in the mu rhythm of the human mirror-neuron system.
Cheng, Yawei; Lee, Po-Lei; Yang, Chia-Yen; Lin, Ching-Po; Hung, Daisy; Decety, Jean
2008-05-07
Psychologically, females are usually thought to be superior in interpersonal sensitivity than males. The human mirror-neuron system is considered to provide the basic mechanism for social cognition. However, whether the human mirror-neuron system exhibits gender differences is not yet clear. We measured the electroencephalographic mu rhythm, as a reliable indicator of the human mirror-neuron system activity, when female (N = 20) and male (N = 20) participants watched either hand actions or a moving dot. The display of the hand actions included androgynous, male, and female characteristics. The results demonstrate that females displayed significantly stronger mu suppression than males when watching hand actions. Instead, mu suppression was similar across genders when participants observed the moving dot and between the perceived sex differences (same-sex vs. opposite-sex). In addition, the mu suppressions during the observation of hand actions positively correlated with the personal distress subscale of the interpersonal reactivity index and negatively correlated with the systemizing quotient. The present findings indirectly lend support to the extreme male brain theory put forward by Baron-Cohen (2005), and may cast some light on the mirror-neuron dysfunction in autism spectrum disorders. The mu rhythm in the human mirror-neuron system can be a potential biomarker of empathic mimicry.
Review disorders of sex development: The evolving role of genomics in diagnosis and gene discovery.
Croft, Brittany; Ayers, Katie; Sinclair, Andrew; Ohnesorg, Thomas
2016-12-01
Disorders of Sex Development (DSDs) are a major paediatric concern and are estimated to occur in around 1.7% of all live births (Fausto-Sterling, Sexing the Body: Gender Politics and the Construction of Sexuality, Basic Books, New York, 2000). They are often caused by the breakdown in the complex genetic mechanisms that underlie gonadal development and differentiation. Having a genetic diagnosis can be important for patients with a DSD: it can increase acceptance of a disorder often surrounded by stigma, alter clinical management and it can assist in reproductive planning. While Massively Parallel Sequencing (MPS) is advancing the genetic diagnosis of rare Mendelian disorders, it is not yet clear which MPS assay is best suited for the clinical diagnosis of DSD patients and to what extent other established methods are still relevant. To complicate matters, DSDs represent a wide spectrum of disorders caused by an array of different genetic changes, many of which are yet unknown. Here we discuss the different genetic lesions that are known to contribute to different DSDs, and review the utility of a range of MPS approaches for diagnosing DSD patients. Birth Defects Research (Part C) 108:337-350, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Yu, Lin; Lu, Jianbo
2011-01-01
The Thousand-Island Lake region in Zhejiang Province, China is a highly fragmented landscape with a clear point-in-time of fragmentation as a result of flooding to form the reservoir. Islands in the artificial lake were surveyed to examine how population sex ratio of a dioecious plant specie Pistacia chinensis B. was affected by landscape fragmentation. A natural population on the mainland near the lake was also surveyed for comparison. Population size, sex ratio and diameter at breast height (DBH) of individuals were measured over 2 years. More than 1,500 individuals, distributed in 31 populations, were studied. Soil nitrogen in the different populations was measured to identify the relationship between sex ratio and micro-environmental conditions. In accordance with the results of many other reports on biased sex ratio in relation to environmental gradient, we found that poor soil nitrogen areas fostered male-biased populations. In addition, the degree of sex ratio bias increased with decreasing population size and population connectivity. The biased sex ratios were only found in younger individuals (less than 50 years old) in small populations, while a stable 1∶1 sex ratio was found in the large population on the mainland. We concluded that the effects of landscape fragmentation on the dioecious population sex ratio were mainly achieved in relation to changing soil nitrogen conditions in patches and pollen limitation within and among populations. Large populations could maintain a more suitable environment in terms of nutrient conditions and pollen flow, subsequently maintaining a stable sex ratio in dioecious plant populations. Both micro-environmental factors and spatial structure should be considered in fragmented landscape for the conservation of dioecious plant species.
Helland, Christian A; Lund-Johansen, Morten; Wester, Knut
2010-11-01
The aim of this study was to examine the distribution of intracranial arachnoid cysts in a large and unselected patient population with special emphasis on sidedness and sex distribution. In total, 299 patients with 305 arachnoid cysts were studied. These patients were consecutively referred to our department during a 20-year period from a well-defined geographical area with a stable population. There was a strong predilection (198 patients [66.2%]) for intracranial arachnoid cysts in the temporal fossa. Forty-two patients had cysts overlying the frontal convexity, 36 had cysts in the posterior fossa, and 23 patients had cysts in other, different locations. Of 269 cysts with clearly unilateral distribution, 163 were located on the left side and 106 on the right side. This difference resulted from the marked preponderance of temporal fossa cysts on the left side (left-to-right ratio 2.5:1; p < 0.0001 [adjusted < 0.0005]). For cysts in the cerebellopontine angle (CPA), there was preponderance on the right side (p = 0.001 [adjusted = 0.005]). Significantly more males than females had cysts in the temporal fossa (p = 0.002 [adjusted = 0.004]), whereas in the CPA a significant female preponderance was found (p = 0.016 [adjusted = 0.032]). For all other cyst locations, there was no difference between the 2 sexes. Arachnoid cysts have a strong predilection for the temporal fossa. There is a sex dependency for some intracranial locations of arachnoid cysts, with temporal cysts occurring more frequently in men, and CPA cysts found more frequently in women. Furthermore, there is a strong location-related sidedness for arachnoid cysts, independent of patient sex. These findings and reports from the literature suggest a possible genetic component in the development of some arachnoid cysts.
Quintela, T; Marcelino, H; Deery, M J; Feret, R; Howard, J; Lilley, K S; Albuquerque, T; Gonçalves, I; Duarte, A C; Santos, C R A
2016-01-01
The choroid plexus (CP) epithelium is a unique structure in the brain that forms an interface between the peripheral blood and the cerebrospinal fluid (CSF), which is mostly produced by the CP itself. Because the CP transcriptome is regulated by the sex hormone background, the present study compared gene/protein expression profiles in the CP and CSF from male and female rats aiming to better understand sex-related differences in CP functions and brain physiology. We used data previously obtained by cDNA microarrays to compare the CP transcriptome between male and female rats, and complemented these data with the proteomic analysis of the CSF of castrated and sham-operated males and females. Microarray analysis showed that 17 128 and 17 002 genes are expressed in the male and female CP, which allowed the functional annotation of 141 and 134 pathways, respectively. Among the most expressed genes, canonical pathways associated with mitochondrial dysfunctions and oxidative phosphorylation were the most prominent, whereas the most relevant molecular and cellular functions annotated were protein synthesis, cellular growth and proliferation, cell death and survival, molecular transport, and protein trafficking. No significant differences were found between males and females regarding these pathways. Seminal functions of the CP differentially regulated between sexes were circadian rhythm signalling, as well as several canonical pathways related to stem cell differentiation, metabolism and the barrier function of the CP. The proteomic analysis identified five down-regulated proteins in the CSF samples from male rats compared to females and seven proteins exhibiting marked variation in the CSF of gonadectomised males compared to sham animals, whereas no differences were found between sham and ovariectomised females. These data clearly show sex-related differences in CP gene expression and CSF protein composition that may impact upon neurological diseases. © 2015 British Society for Neuroendocrinology.
Ruggiero, M J; Boschen, K E; Roth, T L; Klintsova, A Y
2018-06-01
Microglia are involved in various homeostatic processes in the brain, including phagocytosis, apoptosis, and synaptic pruning. Sex differences in microglia colonization of the developing brain have been reported, but have not been established following alcohol insult. Developmental alcohol exposure represents a neuroimmune challenge that may contribute to cognitive dysfunction prevalent in humans with Fetal Alcohol Spectrum Disorders (FASD) and in rodent models of FASD. Most studies have investigated neuroimmune activation following adult alcohol exposure or following multiple exposures. The current study uses a single day binge alcohol exposure model (postnatal day [PD] 4) to examine sex differences in the neuroimmune response in the developing rat hippocampus on PD5 and 8. The neuroimmune response was evaluated through measurement of microglial number and cytokine gene expression at both time points. Male pups had higher microglial number compared to females in many hippocampal subregions on PD5, but this difference disappeared by PD8, unless exposed to alcohol. Expression of pro-inflammatory marker CD11b was higher on PD5 in alcohol-exposed (AE) females compared to AE males. After alcohol exposure, C-C motif chemokine ligand 4 (CCL4) was significantly increased in female AE pups on PD5 and PD8. Tumor necrosis factor-α (TNF-α) levels were also upregulated by AE in males on PD8. The results demonstrate a clear difference between the male and female neuroimmune response to an AE challenge, which also occurs in a time-dependent manner. These findings are significant as they add to our knowledge of specific sex-dependent effects of alcohol exposure on microglia within the developing brain.
Perkins, Kenneth A; Karelitz, Joshua L
2015-04-01
Acute cigarette smoking may relieve withdrawal and negative affect due to tobacco abstinence to a greater extent in women versus men. Yet, the relative contribution of the cigarette's nicotine content to this sex difference is not clear. Non-quitting dependent adult smokers (N = 44; 21 males, 23 females) participated in 2 virtually identical sessions, each after abstaining overnight (CO < 10 ppm) and differing only in the nicotine content of the designated cigarette. While blind to brand markings, they consumed a total of 24 puffs in controlled fashion for 2 hr in each session, either from a nicotine (Quest 1, 0.6 mg) or denicotinized (Quest 3, 0.05 mg) cigarette. Withdrawal symptoms were obtained before and after smoking, and negative affect was assessed after each period of cigarette exposure consisting of 6 puffs every 25 min. Men and women did not differ in baseline withdrawal and negative affect due to overnight abstinence, but reductions in each symptom were significantly influenced by the interaction of sex × nicotine/denicotinized cigarette (both p < .05). In men, but not in women, each symptom was generally decreased more by the nicotine versus denicotinized cigarette, and the nicotine cigarette reduced each to a greater degree in men versus women. Sex differences in relief of abstinence-induced withdrawal and negative affect due to the nicotine content in cigarettes are consistent with prior research indicating that nicotine per se, compared to non-nicotine smoke stimuli, is less rewarding in women versus men. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Sex-Specific Impact of Ischemic Preconditioning on Tissue Oxygenation and Maximal Concentric Force
Paradis-Deschênes, Pénélope; Joanisse, Denis R.; Billaut, François
2017-01-01
Prior peripheral hypoxia induced via remote ischemic preconditioning (IPC) can improve physical performance in male athletes through improved O2 delivery and utilization. Since females may have an innate protective mechanism against ischemia-reperfusion injury, and since muscle metabolism during contraction differs between sexes, it is relevant to examine the impact of sex in response to IPC to determine whether it is also ergogenic in females. In a randomized, crossover, single-blind study, we investigated muscle performance, hemodynamic and O2 uptake in strength-trained males (n = 9) and females (n = 8) performing five sets of 5 maximum voluntary knee extensions on an isokinetic dynamometer, preceded by either IPC (3 × 5-min ischemia/5-min reperfusion cycles at 200 mmHg) or SHAM (20 mmHg). Changes in deoxy-hemoglobin (Δ[HHb], expressed in percentage of arterial occlusion and considered an index of O2 extraction), and total hemoglobin (Δ[THb]) concentrations of the vastus lateralis muscle were continuously monitored by near-infrared spectroscopy. The metabolic efficiency of the contractions was calculated as the average force/Δ[HHb]avg ratio. Cohen's effect sizes (ES) ± 90% confidence limits were used to estimate IPC-induced changes and sex differences. IPC increased total muscular force in males only (13.0%, ES 0.64, 0.37;0.90), and this change was greater than in females (10.4% difference, ES 0.40, 0.10;0.70). Percent force decrement was only attenuated in females (−19.8%, ES −0.38, −0.77;0.01), which was clearly different than males (sex difference: ES 0.45, −0.16;1.07). IPC also induced different changes between sexes for average muscle O2 uptake in set 2 (males: 6.4% vs. females: −16.7%, ES 0.21, −0.18;0.60), set 3 (males: 7.0% vs. females: −44.4%, ES 0.56, −0.17;1.29), set 4 (males: 9.1% vs. females: −40.2%, ES 0.51, −0.10;1.13), and set 5 (males: 10.2% vs. females: −40.4%, ES 0.52, −0.04;1.09). However, metabolic efficiency was not meaningfully different between conditions and sexes. IPC increased muscle blood volume (↑[THb]) at rest and during recovery between sets, to the same extent in both sexes. Despite a similar IPC-induced initial increase in O2 delivery in both sexes, males displayed greater peripheral O2 extraction and greater strength enhancement. This ergogenic effect appears to be mediated in part via an up regulated oxidative function in males. We conclude that strength-trained males might benefit more from IPC than their female counterparts during repeated, maximal efforts. PMID:28105020
Sex-Specific Impact of Ischemic Preconditioning on Tissue Oxygenation and Maximal Concentric Force.
Paradis-Deschênes, Pénélope; Joanisse, Denis R; Billaut, François
2016-01-01
Prior peripheral hypoxia induced via remote ischemic preconditioning (IPC) can improve physical performance in male athletes through improved O 2 delivery and utilization. Since females may have an innate protective mechanism against ischemia-reperfusion injury, and since muscle metabolism during contraction differs between sexes, it is relevant to examine the impact of sex in response to IPC to determine whether it is also ergogenic in females. In a randomized, crossover, single-blind study, we investigated muscle performance, hemodynamic and O 2 uptake in strength-trained males ( n = 9) and females ( n = 8) performing five sets of 5 maximum voluntary knee extensions on an isokinetic dynamometer, preceded by either IPC (3 × 5-min ischemia/5-min reperfusion cycles at 200 mmHg) or SHAM (20 mmHg). Changes in deoxy-hemoglobin (Δ[HHb], expressed in percentage of arterial occlusion and considered an index of O 2 extraction), and total hemoglobin (Δ[THb]) concentrations of the vastus lateralis muscle were continuously monitored by near-infrared spectroscopy. The metabolic efficiency of the contractions was calculated as the average force/Δ[HHb] avg ratio. Cohen's effect sizes (ES) ± 90% confidence limits were used to estimate IPC-induced changes and sex differences. IPC increased total muscular force in males only (13.0%, ES 0.64, 0.37;0.90), and this change was greater than in females (10.4% difference, ES 0.40, 0.10;0.70). Percent force decrement was only attenuated in females (-19.8%, ES -0.38, -0.77;0.01), which was clearly different than males (sex difference: ES 0.45, -0.16;1.07). IPC also induced different changes between sexes for average muscle O 2 uptake in set 2 (males: 6.4% vs. females: -16.7%, ES 0.21, -0.18;0.60), set 3 (males: 7.0% vs. females: -44.4%, ES 0.56, -0.17;1.29), set 4 (males: 9.1% vs. females: -40.2%, ES 0.51, -0.10;1.13), and set 5 (males: 10.2% vs. females: -40.4%, ES 0.52, -0.04;1.09). However, metabolic efficiency was not meaningfully different between conditions and sexes. IPC increased muscle blood volume (↑[THb]) at rest and during recovery between sets, to the same extent in both sexes. Despite a similar IPC-induced initial increase in O 2 delivery in both sexes, males displayed greater peripheral O 2 extraction and greater strength enhancement. This ergogenic effect appears to be mediated in part via an up regulated oxidative function in males. We conclude that strength-trained males might benefit more from IPC than their female counterparts during repeated, maximal efforts.
The Effects of Dietary Macronutrient Balance on Skin Structure in Aging Male and Female Mice
McMahon, Aisling C.; Ruohonen, Kari; Raubenheimer, David; Ballard, J. William O.; Le Couteur, David G.; Nicholls, Caroline; Li, Zhe; Maitz, Peter K. M.; Wang, Yiwei; Simpson, Stephen J.
2016-01-01
Nutrition influences skin structure; however, a systematic investigation into how energy and macronutrients (protein, carbohydrate and fat) affects the skin has yet to be conducted. We evaluated the associations between macronutrients, energy intake and skin structure in mice fed 25 experimental diets and a control diet for 15 months using the Geometric Framework, a novel method of nutritional analysis. Skin structure was associated with the ratio of dietary macronutrients eaten, not energy intake, and the nature of the effect differed between the sexes. In males, skin structure was primarily associated with protein intake, whereas in females carbohydrate intake was the primary correlate. In both sexes, the dermis and subcutaneous fat thicknesses were inversely proportional. Subcutaneous fat thickness varied positively with fat intake, due to enlarged adipocytes rather than increased adipocyte number. We therefore demonstrated clear interactions between skin structure and macronutrient intakes, with the associations being sex-specific and dependent on dietary macronutrient balance. PMID:27832138
Causal attribution of success and failure as a function or authoritarianism and sex.
Goldberg, C; Evenbeck, S
1976-04-01
We predicted that authoritarian actors would engage in defensive attribution, and authoritarian observers would derogate the other, to a greater extent than egalitarian perceivers. 48 male and 48 female college students were run in pairs of same sex and authoritarianism. A set of easy anagrams was given to subjects in success conditions and difficult anagrams to those in failure conditions. Each subject rated own outcome and other outcome in terms of internal factors of ability and effort, and external factors of task and luck. We found that authoritarian actors were more internal than egalitarian actors only in the condition own success-other's failure. Authoritarian observers, as compared to egalitarians, were more external for other's success and more internal for other's failure only when own outcome was successful. It seems that authoritarian perceivers exaggerate their abilities and derogate the other only when they are clearly in a superior position vis-a-vis the other. There were no sex differences as a function of outcome and authoritarianism.
Campanini, Emeline B; Torres, Felipe R; Rezende, Víctor B; Nakamura, Aline M; de Oliveira, Janaína L; Lima, André L A; Chahad-Ehlers, Samira; Sobrinho, Iderval S; de Brito, Reinaldo A
2018-01-01
Abstract Several studies have demonstrated that genes differentially expressed between sexes (sex-biased genes) tend to evolve faster than unbiased genes, particularly in males. The reason for this accelerated evolution is not clear, but several explanations have involved adaptive and nonadaptive mechanisms. Furthermore, the differences of sex-biased expression patterns of closely related species are also little explored out of Drosophila. To address the evolutionary processes involved with sex-biased expression in species with incipient differentiation, we analyzed male and female transcriptomes of Anastrepha fraterculus and Anastrepha obliqua, a pair of species that have diverged recently, likely in the presence of gene flow. Using these data, we inferred differentiation indexes and evolutionary rates and tested for signals of selection in thousands of genes expressed in head and reproductive transcriptomes from both species. Our results indicate that sex-biased and reproductive-biased genes evolve faster than unbiased genes in both species, which is due to both adaptive pressure and relaxed constraints. Furthermore, among male-biased genes evolving under positive selection, we identified some related to sexual functions such as courtship behavior and fertility. These findings suggest that sex-biased genes may have played important roles in the establishment of reproductive isolation between these species, due to a combination of selection and drift, and unveil a plethora of genetic markers useful for more studies in these species and their differentiation. PMID:29346618
Molecular marker suggests rapid changes of sex-determining mechanisms in Australian dragon lizards.
Ezaz, Tariq; Quinn, Alexander E; Sarre, Stephen D; O'Meally, Denis; Georges, Arthur; Graves, Jennifer A Marshall
2009-01-01
Distribution of sex-determining mechanisms across Australian agamids shows no clear phylogenetic segregation, suggesting multiple transitions between temperature-dependent (TSD) and genotypic sex determination (GSD). These taxa thus present an excellent opportunity for studying the evolution of sex chromosomes, and evolutionary transitions between TSD and GSD. Here we report the hybridization of a 3 kb genomic sequence (PvZW3) that marks the Z and W microchromosomes of the Australian central bearded dragon (Pogona vitticeps) to chromosomes of 12 species of Australian agamids from eight genera using fluorescence in-situ hybridization (FISH). The probe hybridized to a single microchromosome pair in 11 of these species, but to the tip of the long arm of chromosome pair 2 in the twelfth (Physignathus lesueurii), indicating a micro-macro chromosome rearrangement. Three TSD species shared the marked microchromosome, implying that it is a conserved autosome in related species that determine sex by temperature. C-banding identified the marked microchromosome as the heterochromatic W chromosome in two of the three GSD species. However, in Ctenophorus fordi, the probe hybridized to a different microchromosome from that shown by C-banding to be the heterochromatic W, suggesting an independent origin for the ZW chromosome pair in that species. Given the haphazard distribution of GSD and TSD in this group and the existence of at least two sets of sex microchromosomes in GSD species, we conclude that sex-determining mechanisms in this family have evolved independently, multiple times in a short evolutionary period.
Age and sex bias in the reconstruction of past population structures.
Bello, Silvia M; Thomann, Aminte; Signoli, Michel; Dutour, Olivier; Andrews, Peter
2006-01-01
Palaeodemographical studies are founded on the assumption that the sex and age distribution of the skeletal sample reflects the constitution of the original population. It is becoming increasingly clear, however, that the type and amount of information that may be derived from osteoarchaeological collections are related to the state of preservation of remains. This work proposes a new method to evaluate bone preservation, to identify age and sex biases in the preservation of human skeletal remains, and to assess whether differences in preservation patterns are more dependent on factors intrinsic or extrinsic to anatomical features of human bones. Three osteological collections and over 600 skeletons were observed. The state of preservation of human bones was assessed using three preservation indexes: the anatomical preservation index (API), the bone representation index (BRI), and the qualitative bone index (QBI). The results suggest that subadult skeletons are generally more poorly preserved and with bones less well-represented than adult skeletons. Among subadults, female and male skeletons have different patterns of preservation according to their age. This pattern of preservation depends on intrinsic anatomical properties of bones themselves, while external factors can only increase these differences in the state of preservation and representation of osseous remains. It is concluded from this that failure to recognize these differences may lead to misleading interpretations of paleodemography of past human populations.
Reducing voluntary, avoidable turnover through selection.
Barrick, Murray R; Zimmerman, Ryan D
2005-01-01
The authors investigated the efficacy of several variables used to predict voluntary, organizationally avoidable turnover even before the employee is hired. Analyses conducted on applicant data collected in 2 separate organizations (N = 445) confirmed that biodata, clear-purpose attitudes and intentions, and disguised-purpose dispositional retention scales predicted voluntary, avoidable turnover (rs ranged from -.16 to -.22, R = .37, adjusted R = .33). Results also revealed that biodata scales and disguised-purpose retention scales added incremental validity, whereas clear-purpose retention scales did not explain significant incremental variance in turnover beyond what was explained by biodata and disguised-purpose scales. Furthermore, disparate impact (subgroup differences on race, sex, and age) was consistently small (average d = 0.12 when the majority group scored higher than the minority group).
Wright, Jonathan; McDonald, Paul G.; te Marvelde, Luc; Kazem, Anahita J. N.; Bishop, Charles M.
2010-01-01
Indirect fitness benefits from kin selection can explain why non-breeding individuals help raise the young of relatives. However, the evolution of helping by non-relatives requires direct fitness benefits, for example via group augmentation. Here, we examine nest visit rates, load sizes and prey types delivered by breeding pairs and their helpers in the cooperatively breeding bell miner (Manorina melanophrys). In this system, males remain in their natal colony while young females typically disperse, and helpers of both sexes often assist at multiple nests concurrently. We found extremely clear evidence for the expected effect of genetic relatedness on individual helping effort per nest within colonies. This positive incremental effect of kinship was facultative—i.e. largely the result of within-individual variation in helping effort. Surprisingly, no sex differences were detectable in any aspect of helping, and even non-relatives provided substantial aid. Helpers and breeders of both sexes regulated their provisioning effort by responding visit-by-visit to changes in nestling begging. Helping behaviour in bell miners therefore appears consistent with adaptive cooperative investment in the brood, and kin-selected care by relatives. Similar investment by ‘unrelated’ helpers of both sexes argues against direct fitness benefits, but is perhaps explained by kin selection at the colony level. PMID:19846458
Dixson, Barnaby J.
2016-01-01
Human mate choice research often concerns sex differences in the importance of traits such as physical attractiveness and social status. A growing number of studies indicate that cues to social context, including other people who appear in stimulus photographs, can alter that individual’s attractiveness. Fewer studies, however, consider judgements of traits other than physical attractiveness, such as wealth. Here we manipulate the presence/absence of other people in photographs of target models, and test the effects on judgments of both attractiveness and earnings (a proxy for status). Participants (N = 2044) rated either male or female models for either physical attractiveness or social/economic status when presented alone, with same sex others or with opposite sex others. We collectively refer to this manipulation as ‘social context’. Male and female models received similar responses for physical attractiveness, but social context affected ratings of status differently for women and men. Males presented alongside other men received the highest status ratings while females presented alone were given the highest status ratings. Further, the status of females presented alongside a male was constrained by the rated status of that male. Our results suggests that high status may not directly lead to high attractiveness in men, but that status is more readily attributed to men than to women. This divide in status between the sexes is very clear when men and women are presented together, possibly reflecting one underlying mechanism of the modern day gender gap and sexist attitudes to women’s economic participation. This adds complexity to our understanding of the relationship between attractiveness, status, and sex in the light of parental investment theory, sexual conflict and economic theory. PMID:26731414
van Oeffelen, Aloysia A M; Vaartjes, Ilonca; Stronks, Karien; Bots, Michiel L; Agyemang, Charles
2015-02-01
The incidence of acute myocardial infarction (AMI) in men exceeds that in women. The extent of this sex disparity varies widely between countries. Variations may also exist between ethnic minority groups and the majority population, but scientific evidence is lacking. A nationwide register-based cohort study was conducted (n = 7,601,785) between 1997 and 2007. Cox Proportional Hazard Models were used to estimate sex disparities in AMI incidence within the Dutch majority population and within ethnic minority groups, stratified by age (30-54, 55-64, ≥65 years). AMI incidence was higher in men than in women in all groups under study. Compared with the majority population (hazard ratio (HR): 2.23; 95% confidence interval (95% CI): 2.21-2.25), sex disparities were similar among minorities originating from the immediate surrounding countries (Belgium, Germany), whereas they were greater in most other minority groups. Most pronounced results were found among minorities from Morocco (HR: 3.48; 95% CI: 2.48-4.88), South Asia (HR: 3.92; 95% CI: 2.45-6.26) and Turkey (HR: 3.98; 95% CI: 3.51-4.51). Sex disparity differences were predominantly evident in those below 55 years of age, and were mainly provoked by a higher AMI incidence in ethnic minority men compared with men belonging to the Dutch majority population. Sex disparities in AMI incidence clearly varied between ethnic minorities and the Dutch majority population. Health prevention strategies may first target at a reduction of AMI incidence in young ethnic minority men, especially those originating from Turkey and South Asia. Furthermore, an increase in AMI incidence in their female counterparts should be prevented. © The European Society of Cardiology 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
Gouda-Vossos, Amany; Dixson, Barnaby J; Brooks, Robert C
2016-01-01
Human mate choice research often concerns sex differences in the importance of traits such as physical attractiveness and social status. A growing number of studies indicate that cues to social context, including other people who appear in stimulus photographs, can alter that individual's attractiveness. Fewer studies, however, consider judgements of traits other than physical attractiveness, such as wealth. Here we manipulate the presence/absence of other people in photographs of target models, and test the effects on judgments of both attractiveness and earnings (a proxy for status). Participants (N = 2044) rated either male or female models for either physical attractiveness or social/economic status when presented alone, with same sex others or with opposite sex others. We collectively refer to this manipulation as 'social context'. Male and female models received similar responses for physical attractiveness, but social context affected ratings of status differently for women and men. Males presented alongside other men received the highest status ratings while females presented alone were given the highest status ratings. Further, the status of females presented alongside a male was constrained by the rated status of that male. Our results suggests that high status may not directly lead to high attractiveness in men, but that status is more readily attributed to men than to women. This divide in status between the sexes is very clear when men and women are presented together, possibly reflecting one underlying mechanism of the modern day gender gap and sexist attitudes to women's economic participation. This adds complexity to our understanding of the relationship between attractiveness, status, and sex in the light of parental investment theory, sexual conflict and economic theory.
de Vries, Annelou L C; Doreleijers, Theo A H; Cohen-Kettenis, Peggy T
2007-06-01
This article reviews studies on gender identity outcome in individuals with disorders of sex development (DSD). It appears that a high percentage of affected individuals suffer from gender dysphoria. However, these figures differ substantially among the various DSD and they never reach 100%. From the studies it also becomes clear that a distinction should be made between gender role behavior and gender identity. Put in a broader theoretical framework, there is now more evidence that biological factors influence the development of gender role behavior than gender identity. Developmental psychology studies add evidence that social and psychological factors play a role as well in gender development. Clinicians should be aware of, but not overestimate the influences of neurobiological factors in gender development.
[Different sedimentation rates of X- and Y- sperm and the question of arbitrary sex determination].
Bhattacharya, B C
1962-01-01
Separation of X and Y sperm using their sedimentation rates is repor ted. A colloidal medium (egg yolk and glycocoll solution) of a particular viscosity and density was developed for this purpose. Rabbit and bull sperm yeilded a 2-peaked curve when separated into sedimentatio n fractions, while rooster sperm gave a single-peak curve. Sedimentation rate of live and dead sperm were similar. 176 female rabbits were fertilized with various sedimentation fractions. 23.3% became pregnant, resulting in 122 young. The sex of the young was clearly related to the sedimentation rate of the sperm: the 2 uppermost fractions yielded 77.4% (P 0.01) male offspring, while the 2 lowest fractions gave 28.2% males (p 0.01) and the middle yielded 54.7% male young.
Incomplete offspring sex bias in Australian populations of the butterfly Eurema hecabe
Kemp, D J; Thomson, F E; Edwards, W; Iturbe-Ormaetxe, I
2017-01-01
Theory predicts unified sex ratios for most organisms, yet biases may be engendered by selfish genetic elements such as endosymbionts that kill or feminize individuals with male genotypes. Although rare, feminization is established for Wolbachia-infected Eurema butterflies. This paradigm is presently confined to islands in the southern Japanese archipelago, where feminized phenotypes produce viable all-daughter broods. Here, we characterize sex bias for E. hecabe in continental Australia. Starting with 186 wild-caught females, we reared >6000 F1–F3 progeny in pedigree designs that incorporated selective antibiotic treatments. F1 generations expressed a consistent bias across 2 years and populations that was driven by an ~5% incidence of broods comprising ⩾80% daughters. Females from biased lineages continued to overproduce daughters over two generations of outcrossing to wild males. Treatment with antibiotics of differential strength influenced sex ratio only in biased lineages by inducing an equivalent incomplete degree of son overproduction. Brood sex ratios were nevertheless highly variable within lineages and across generations. Intriguingly, the cytogenetic signature of female karyotype was uniformly absent, even among phenotypic females in unbiased lineages. Molecular evidence supported the existence of a single Wolbachia strain at high prevalence, yet this was not clearly linked to brood sex bias. In sum, we establish an inherited, experimentally reversible tendency for incomplete offspring bias. Key features of our findings clearly depart from the Japanese feminization paradigm and highlight the potential for more subtle degrees of sex distortion in arthropods. PMID:27731327
Affective Domain Progression in Single-Sex and Coeducational Schools
ERIC Educational Resources Information Center
Dhindsa, Harkirat S.; Salleh, Siti-Zahrani Binti Haji Md
2018-01-01
Students who study science in single-sex and coeducational schools have attracted lots of attention from the education community. However, changes to students' attitudes toward science as they progress to higher grades in these schools are not clearly understood. The aim of this study was to compare the changes in attitudes toward science among…
Vocal and Gestural Productions of 24-Month-Old Children with Sex Chromosome Trisomies
ERIC Educational Resources Information Center
Zampini, Laura; Draghi, Lara; Silibello, Gaia; Dall'Ara, Francesca; Rigamonti, Claudia; Suttora, Chiara; Zanchi, Paola; Salerni, Nicoletta; Lalatta, Faustina; Vizziello, Paola
2018-01-01
Background: Children with sex chromosome trisomies (SCT) frequently show problems in language development. However, a clear description of the communicative patterns of these children is still lacking. Aims: To describe the first stages of language development in children with SCT in comparison with those in typically developing (TD) children. The…
Single-Sex Schooling in Trinidad and Tobago: a Holistic Exploration
ERIC Educational Resources Information Center
Blair, Erik
2013-01-01
Single-sex schooling has been proposed as a way of addressing the disengagement of boys; the disproportion of gender in certain subjects; stereotyped gender images, and the labelling of some subjects as "masculine" or "feminine". However, there exists no clear research evidence to support such claims. Despite the lack of…
Lacey, Michael J; Sémon, Etienne; Krasulová, Jana; Sillam-Dussès, David; Robert, Alain; Cornette, Richard; Hoskovec, Michal; Záček, Petr; Valterová, Irena; Bordereau, Christian
2011-12-01
The trail-following pheromone and sex pheromones were investigated in the Indomalayan termite Hodotermopsis sjoestedti belonging to the new family Archotermopsidae. Gas chromatography coupled to mass spectrometry (GC-MS) after solid phase microextraction (SPME) of the sternal gland secretion of pseudergates and trail-following bioassays demonstrated that the trail-following pheromone of H. sjoestedti was syn-4,6-dimethylundecan-1-ol, a new chemical structure for termite pheromones. GC-MS after SPME of the sternal gland secretion of alates also allowed the identification of sex-specific compounds. In female alates, the major sex-specific compound was identified as (5E)-2,6,10-trimethylundeca-5,9-dienal, a compound previously identified as the female sex pheromone of the termite Zootermopsis nevadensis. In male alates, the major sex-specific compound was identified as syn-4,6-dimethylundecanal, a homolog of syn-4,6-dimethyldodecanal, which has previously been confirmed as the male sex pheromone of Z. nevadensis. The presence of sex-specific compounds in alates of H. sjoestedti strongly suggests for this termite the presence of sex-specific pairing pheromones which were only known until now in Z. nevadensis. Our results showed therefore a close chemical relationship between the pheromones of the taxa Hodotermopsis and Zootermopsis and, in contrast, a clear difference with the taxa Stolotermes and Porotermes, which is in total agreement with the recent creation of the families Archotermopsidae and Stolotermitidae as a substitute for the former family Termopsidae. Copyright © 2011 Elsevier Ltd. All rights reserved.
Competing for jobs: labor queues and gender sorting in the hiring process.
Fernandez, Roberto M; Mors, Marie Louise
2008-12-01
While much research has documented the pattern and extent of sex segregation of workers once they are employed, few studies have addressed the pre-hire mechanisms that are posited to produce sex segregation in employment. While the notion of a labor queue-the rank order of the set of people that employers choose among-plays a prominent role in pre-hire accounts of job sex sorting mechanisms, few studies have examined the ways in which job candidates are sorted into labor queues. In this paper, we explore the mechanisms by which labor queues contribute to the gendering of jobs by studying the hiring process for all jobs at a call center. Being placed in a queue has a clear gendering effect on the hiring process: the sex distribution of applicants who are matched to queues and those who are rejected at this phase diverge, and among those assigned to queues, women are prevalent in queues for low pay, low status jobs. The screening process also contributes to the gendering of the population of hires at this firm. Females are more prevalent among hires than they are among candidates at initial queue assignment. Among high status jobs, however, males are more prevalent than females. Moreover, there are important wage implications associated with matching to queues. While there are large between-queue sex differences in the paid wages associated with allocation to queues, once allocated to queues the wage differences between male and female candidates are nil. Consequently, the roots of gender wage inequality in this setting lie in the initial sorting of candidates to labor queues.
Sex, shoulder pain, and range of motion in manual wheelchair users.
Wessels, Karla K; Brown, Jennifer L; Ebersole, Kyle T; Sosnoff, Jacob J
2013-01-01
Upwards of 70% of manual wheelchair users (MWUs) experience shoulder pain. Pain is more prevalent among females than males. The causes of this sex discrepancy are not understood. Decreased range of motion (ROM) has been suggested as a major contributor, but the interaction of sex, ROM, and shoulder pain has not been investigated, thus the purpose of this investigation. We divided 30 MWUs (18 males, 12 females; 21.93 +/- 3.77 yr) into two groups based on self-reported shoulder pain: pain group (n = 14; 9 males, 5 females) and no pain group (n = 16; 9 males, 7 females). We used a digital goniometer to assess ROM. Participants' shoulder active and passive ROMs were tested bilaterally on the following joint motions: flexion, extension, abduction, adduction, internal rotation, and external rotation. We used a visual analog scale to assess shoulder pain. Of the participants, 47% reported shoulder pain. Overall, the no pain group had greater ROM than the pain group, with further analysis revealing this association was only significant in females during extension (p < 0.05). ROM impairments were only present in extension in females with shoulder pain. The mechanism underlying this sex difference is not clear.
van de Beek, Cornelieke; van Goozen, Stephanie H M; Buitelaar, Jan K; Cohen-Kettenis, Peggy T
2009-02-01
Testosterone, estradiol, and progesterone levels were measured in the second trimester of pregnancy in maternal serum and amniotic fluid, and related to direct observations of gender-related play behavior in 63 male and 63 female offspring at age 13 months. During a structured play session, sex differences in toy preference were found: boys played more with masculine toys than girls (d = .53) and girls played more with feminine toys than boys (d = .35). Normal within-sex variation in prenatal testosterone and estradiol levels was not significantly related to preference for masculine or feminine toys. For progesterone, an unexpected significant positive relationship was found in boys between the level in amniotic fluid and masculine toy preference. The mechanism explaining this relationship is presently not clear, and the finding may be a spurious one. The results of this study may indicate that a hormonal basis for the development of sex-typed toy preferences may manifest itself only after toddlerhood. It may also be that the effect size of this relationship is so small that it should be investigated with more sensitive measures or in larger populations.
Moscicki, Anna-Barbara; Ma, Yifei; Farhat, Sepideh; Jay, Julie; Hanson, Evelyn; Benningfield, Susanna; Jonte, Janet; Godwin-Medina, Cheryl; Wilson, Robert; Shiboski, Stephen
2014-03-01
Anal cancer is more common in women than in men, yet little is known about the natural history of human papillomavirus (HPV) in women. The objective was to examine the natural history of anal HPV in heterosexual women. Young women participating in an HPV cohort study were seen at 4-month intervals for cervical and anal HPV testing. Time to clearance was estimated using the Kaplan-Meier approach; risks for persistence were assessed using Cox regression models. Seventy-five women (mean age, 23.5 ± 4.1 years) who tested positive for anal HPV were followed for a mean of 84.5 ± 44.9 months. By 3 years, 82.5% of anal non-16 high-risk (HR) HPV, 82.6% of low-risk (LR) HPV, and 76.2% of HPV-16 infections had cleared. By 3 years, only 36.4% of women had become negative for all HPV types. In the multivariable model, concurrent cervical HPV-16 (P < .001), weekly alcohol use (P = .015), anal touching during sex (P = .045), recent anal sex (P = .04), and no condom use during anal sex (P = .04) were associated with HPV-16 persistence. Greater number of new sex partners (P = .024) and condom use during vaginal sex (P = .003) were associated with clearance. Similar associations were found for clearance in all HR-HPV infections. Only concomitant cervical HPV was associated with non-16 HR-HPV persistence. The majority of anal HPV infections cleared within 3 years. HPV-16 infections were slower to clear than other HR-HPV infections, consistent with its role in anal cancer. Specific sexual behaviors were associated with persistence, suggesting that education and behavioral interventions may decrease persistence.
Moscicki, Anna-Barbara; Ma, Yifei; Farhat, Sepideh; Jay, Julie; Hanson, Evelyn; Benningfield, Susanna; Jonte, Janet; Godwin-Medina, Cheryl; Wilson, Robert; Shiboski, Stephen
2014-01-01
Background. Anal cancer is more common in women than in men, yet little is known about the natural history of human papillomavirus (HPV) in women. The objective was to examine the natural history of anal HPV in heterosexual women. Methods. Young women participating in an HPV cohort study were seen at 4-month intervals for cervical and anal HPV testing. Time to clearance was estimated using the Kaplan-Meier approach; risks for persistence were assessed using Cox regression models. Results. Seventy-five women (mean age, 23.5 ± 4.1 years) who tested positive for anal HPV were followed for a mean of 84.5 ± 44.9 months. By 3 years, 82.5% of anal non-16 high-risk (HR) HPV, 82.6% of low-risk (LR) HPV, and 76.2% of HPV-16 infections had cleared. By 3 years, only 36.4% of women had become negative for all HPV types. In the multivariable model, concurrent cervical HPV-16 (P < .001), weekly alcohol use (P = .015), anal touching during sex (P = .045), recent anal sex (P = .04), and no condom use during anal sex (P = .04) were associated with HPV-16 persistence. Greater number of new sex partners (P = .024) and condom use during vaginal sex (P = .003) were associated with clearance. Similar associations were found for clearance in all HR-HPV infections. Only concomitant cervical HPV was associated with non-16 HR-HPV persistence. Conclusions. The majority of anal HPV infections cleared within 3 years. HPV-16 infections were slower to clear than other HR-HPV infections, consistent with its role in anal cancer. Specific sexual behaviors were associated with persistence, suggesting that education and behavioral interventions may decrease persistence. PMID:24368624
Doull, Marion; Welch, Vivian; Puil, Lorri; Runnels, Vivien; Coen, Stephanie E; Shea, Beverley; O'Neill, Jennifer; Borkhoff, Cornelia; Tudiver, Sari; Boscoe, Madeline
2014-01-01
There is increasing recognition of sex/gender differences in health and the importance of identifying differential effects of interventions for men and women. Yet, to whom the research evidence does or does not apply, with regard to sex/gender, is often insufficiently answered. This is also true for systematic reviews which synthesize results of primary studies. A lack of analysis and reporting of evidence on sex/gender raises concerns about the applicability of systematic reviews. To bridge this gap, this pilot study aimed to translate knowledge about sex/gender analysis (SGA) into a user-friendly 'briefing note' format and evaluate its potential in aiding the implementation of SGA in systematic reviews. Our Sex/Gender Methods Group used an interactive process to translate knowledge about sex/gender into briefing notes, a concise communication tool used by policy and decision makers. The briefing notes were developed in collaboration with three Cochrane Collaboration review groups (HIV/AIDS, Hypertension, and Musculoskeletal) who were also the target knowledge users of the briefing notes. Briefing note development was informed by existing systematic review checklists, literature on sex/gender, in-person and virtual meetings, and consultation with topic experts. Finally, we held a workshop for potential users to evaluate the notes. Each briefing note provides tailored guidance on considering sex/gender to reviewers who are planning or conducting systematic reviews and includes the rationale for considering sex/gender, with examples specific to each review group's focus. Review authors found that the briefing notes provided welcome guidance on implementing SGA that was clear and concise, but also identified conceptual and implementation challenges. Sex/gender briefing notes are a promising knowledge translation tool. By encouraging sex/gender analysis and equity considerations in systematic reviews, the briefing notes can assist systematic reviewers in ensuring the applicability of research evidence, with the goal of improved health outcomes for diverse populations.
Furnham, Adrian; Arteche, Adriane; Chamorro-Premuzic, Tomas; Keser, Askin; Swami, Viren
2009-12-01
This study is part of a programmatic research effort into the determinants of self-assessed abilities. It examined cross-cultural differences in beliefs about intelligence and self- and other-estimated intelligence in two countries at extreme ends of the European continent. In all, 172 British and 272 Turkish students completed a three-part questionnaire where they estimated their parents', partners' and own multiple intelligences (Gardner (10) and Sternberg (3)). They also completed a measure of the 'big five' personality scales and rated six questions about intelligence. The British sample had more experience with IQ tests than the Turks. The majority of participants in both groups did not believe in sex differences in intelligence but did think there were race differences. They also believed that intelligence was primarily inherited. Participants rated their social and emotional intelligence highly (around one standard deviation above the norm). Results suggested that there were more cultural than sex differences in all the ratings, with various interactions mainly due to the British sample differentiating more between the sexes than the Turks. Males rated their overall, verbal, logical, spatial, creative and practical intelligence higher than females. Turks rated their musical, body-kinesthetic, interpersonal and intrapersonal intelligence as well as existential, naturalistic, emotional, creative, and practical intelligence higher than the British. There was evidence of participants rating their fathers' intelligence on most factors higher than their mothers'. Factor analysis of the ten Gardner intelligences yield two clear factors: cognitive and social intelligence. The first factor was impacted by sex but not culture; it was the other way round for the second factor. Regressions showed that five factors predicted overall estimates: sex (male), age (older), test experience (has done tests), extraversion (strong) and openness (strong). Results are discussed in terms of the growing literature in the field.
Sex Differences in Smoking Cessation Pharmacotherapy Comparative Efficacy: A Network Meta-analysis
Weinberger, Andrea H.; Zhang, Ju; Emme, Erin; Mazure, Carolyn M.; McKee, Sherry A.
2017-01-01
Abstract Introduction: Converging clinical and biological evidence suggest sex is an important factor when selecting a pharmacological intervention for smoking cessation. The current investigation used network meta-analyses to estimate sex differences in the comparative efficacy of transdermal nicotine (TN), varenicline, and sustained release (SR) bupropion for smoking cessation. Methods: Systematically searched previously published reviews and databases (Medline, PsycINFO, Embase) of randomized, double-blind, placebo-controlled trials of bupropion-SR, TN, and varenicline for cigarette smoking cessation in primary care/general community samples were included. Results: Thirty-two studies met all criteria and 28 (88%) were included in the final analyses, representing 14 389 smokers (51% female). Results of the full sample (women and men combined) mirrored those from a Cochrane Tobacco Addiction Group network meta-analysis of smoking cessation pharmacotherapy, showing VAR>TN=BUP. All medications improved quit rates over placebo for both women and men. Relative to placebo, varenicline efficacy was similar for women and men. Significant sex differences were evident when comparing varenicline versus TN and varenicline versus bupropion. For women, varenicline was more efficacious than TN (RR = 1.41; 95% CI = 1.12,1.76) and bupropion (RR = 1.38; 95% CI = 1.08,1.77). For men, outcomes for those treated with TN and bupropion were similar to those treated with varenicline. There were no differences in efficacy when comparing bupropion versus TN. Conclusions: The advantage of varenicline over bupropion SR and TN is greater for women than men. Clinicians should strongly consider varenicline as the first option treatment for women. Among men, the advantage of varenicline over TN or bupropion is less clear. Implications: This study provides information for the sex-informed treatment of nicotine addiction among cigarette smokers. Relative to placebo, women and men achieved similar outcomes when treated with varenicline; however the advantages of varenicline over transdermal patch and bupropion were greater for women compared to men. PMID:27613893
Espín, Laura; Marquina, Mónica; Hidalgo, Vanesa; Salvador, Alicia; Gómez-Amor, Jesús
2016-11-01
Generalized Social Phobia (GSP) is a common anxiety disorder that produces clear social life disruptions. There is no consensus on the specific processes involved in its development, but the role of the hypothalamic-pituitary-adrenal (HPA) axis has been suggested. This study analyzed the effects of the cortisol response to the Trier Social Stress Test (TSST) on the memory retrieval of pictures with different emotional valences in 45 non-treated young students with GSP and 50 non-anxious (NA) subjects (mean=19.35years, SD=0.18). No differences were found in the cortisol response of GSP and NA subjects to the TSST and control sessions. In addition, psychosocial stress impaired memory retrieval in both the GSP and NA groups, with no differences between them. Regarding the sex factor, no effects were found in the cortisol response to the TSST. However, during the encoding session, GSP men had higher cortisol levels than GSP women and NA subjects. There was also a significant interaction between sex and stress exposure on memory retrieval. Women recognized more unpleasant and neutral pictures than men; however, under stress, the women's advantage disappeared, and the men's performance improved. Sex also interacted with social phobia on positive mood, with GSP women exposed to the TSST showing the lowest positive mood. These results suggest that GSP subjects do not present an HPA axis sensitization to psychosocial stress, and they emphasize the importance of Sex in understanding stress effects on memory. Copyright © 2016 Elsevier Ltd. All rights reserved.
Trends in the earnings gender gap among dentists, physicians, and lawyers.
Nguyen Le, Thanh An; Lo Sasso, Anthony T; Vujicic, Marko
2017-04-01
The authors examined the factors associated with sex differences in earnings for 3 professional occupations. The authors used a multivariate Blinder-Oaxaca method to decompose the differences in mean earnings across sex. Although mean differences in earnings between men and women narrowed over time, there remained large, unaccountable earnings differences between men and women among all professions after multivariate adjustments. For dentists, the unexplained difference in earnings for women was approximately constant at 62% to 66%. For physicians, the unexplained difference in earnings for women ranged from 52% to 57%. For lawyers, the unexplained difference in earnings for women was the smallest of the 3 professions but also exhibited the most growth, increasing from 34% in 1990 to 45% in 2010. The reduction in the earnings gap is driven largely by a general convergence between men and women in some, but not all, observable characteristics over time. Nevertheless, large unexplained gender gaps in earnings remain for all 3 professions. Policy makers must use care in efforts to alleviate earnings differences for men and women because measures could make matters worse without a clear understanding of the nature of the factors driving the differences. Copyright © 2017 American Dental Association. Published by Elsevier Inc. All rights reserved.
Angelopoulou, Roxani; Lavranos, Giagkos; Manolakou, Panagiota
2008-03-20
Chromosomal sex determination is a widely distributed strategy in nature. In the most classic scenario, one sex is characterized by a homologue pair of sex chromosomes, while the other includes two morphologically and functionally distinct gonosomes. In mammalian diploid cells, the female is characterized by the presence of two identical X chromosomes, while the male features an XY pair, with the Y bearing the major genetic determinant of sex, i.e. the SRY gene. In other species, such as the fruitfly, sex is determined by the ratio of autosomes to X chromosomes. Regardless of the exact mechanism, however, all these animals would exhibit a sex-specific gene expression inequality, due to the different number of X chromosomes, a phenomenon inhibited by a series of genetic and epigenetic regulatory events described as "dosage compensation". Since adequate available data is currently restricted to worms, flies and mammals, while for other groups of animals, such as reptiles, fish and birds it is very limited, it is not yet clear whether this is an evolutionary conserved mechanism. However certain striking similarities have already been observed among evolutionary distant species, such as Drosophila melanogaster and Mus musculus. These mainly refer to a) the need for a counting mechanism, to determine the chromosomal content of the cell, i.e. the ratio of autosomes to gonosomes (a process well understood in flies, but still hypothesized in mammals), b) the implication of non-translated, sex-specific, regulatory RNAs (roX and Xist, respectively) as key elements in this process and the location of similar mediators in the Z chromosome of chicken c) the inclusion of a chromatin modification epigenetic final step, which ensures that gene expression remains stably regulated throughout the affected area of the gonosome. This review summarizes these points and proposes a possible role for comparative genetics, as they seem to constitute proof of maintained cell economy (by using the same basic regulatory elements in various different scenarios) throughout numerous centuries of evolutionary history.
Examining relationships between anxiety and dangerous driving.
Dula, Chris S; Adams, Cristi L; Miesner, Michael T; Leonard, Robin L
2010-11-01
Driving anxiety that has developed following crashes has been studied relatively frequently, but anxiety per se and its effects on driving has not as yet garnered much attention in the literature. The current study included 1121 participants and found higher levels of general anxiety were related to a wide variety of dangerous driving behaviors. While there were clear and expected sex differences on many dangerous driving variables, there were still more such differences with regard to anxiety levels and independent of sex, higher levels of anxiety were associated with greater levels of dangerous driving. Of particular import, it was found that the high anxiety group had caused significantly more crashes and engaged in more DUI episodes than the low and/or medium anxiety groups. Taken as a whole, the results suggest there is a tremendous need for more research in the area of anxiety and dangerous driving and that interventions for highly anxious drivers may well be warranted. 2010 Elsevier Ltd. All rights reserved.
Spouse selection in Canada, 1921-78: an examination by age, sex and religion.
Basavarajappa, K G; Norris, M J; Halli, S S
1988-04-01
This paper presents time series data on spouse selection in Canada for the period 1921-1978. Homogamous and endogamous trends are examined by age, sex, and religion. In the case of religious endogamy, most groups have shown decreasing proportions of marriages. There are also considerable differences in rates of endogamy among religious groups, and these differences have largely persisted over time. Until 1971, the proportions of brides marrying older and younger grooms decreased, while the proportion marrying the same age increased, after which these trends reversed. Younger males increasingly tended to select brides of their own age group until the 1960s, while older males have been increasingly heterogamous since World War II. While these changes in spouse selection have been examined with respect to changes in the unmarried population, the relation between the 2 trends is not clear, and it is difficult to account fully for the observed trends in spouse selection with respect to age.
The Sex and Gender Intersection in Chronic Periodontitis
Ioannidou, Effie
2017-01-01
Periodontitis, a complex polymicrobial inflammatory disease, is a public health burden affecting more than 100 million people and being partially responsible for tooth loss. Interestingly, periodontitis has a documented higher prevalence in men as compared to women signifying a possible sex/gender entanglement in the disease pathogenesis. Although relevant evidence has treated sex/gender in a simplistic dichotomous manner, periodontitis may represent a complex inflammatory disease model, in which sex biology may interfere with gender social and behavioral constructs affecting disease clinical phenotype. Even when it became clear that experimental oral health research needed to incorporate gender (and/or sex) framework in the hypothesis, researchers overwhelmingly ignored it unless the research question was directly related to reproductive system or sex-specific cancer. With the recognition of gender medicine as an independent field of research, this study challenged the current notion regarding sex/gender roles in periodontal disease. We aimed to develop the methodological and analytical framework with the recognition of sex/gender as important determinants of disease pathogenesis that require special attention. First, we aim to present relevant sex biologic evidence to understand the plausibility of the epidemiologic data. In periodontitis pathogenesis, sex dimorphism has been implicated in the disease etiology possibly affecting the bacterial component and the host immune response both in the innate and adaptive levels. With the clear distinction between sex and gender, gender oral health disparities have been explained by socioeconomic factors, cultural attitudes as well as access to preventive and regular care. Economic inequality and hardship for women have resulted in limited access to oral care. As a result, gender emerged as a complex socioeconomic and behavioral factor influencing oral health outcomes. Taken together, as disease phenotypic presentation is a multifactorial product of biology, behavior and the environment, sex dimorphism in immunity as well as gender socio-behavioral construct might play a role in the above model. Therefore, this paper will provide the conceptual framework and principles intergrading sex and gender within periodontal research in a complex biologic and socio-behavioral dimension. PMID:28824898
Sex-Role Stereotyping of Occupations: Have We Come a Long Way?
ERIC Educational Resources Information Center
Geffner, Robert; And Others
Research has indicated a reduction in overt sex-role discrimination in employment for women, but it is not clear whether stereotypical attitudes concerning the job market have changed. To compare current students' attitudes toward several occupations with the attitudes of students 10 years ago, 105 male and female students rated 22 occupations on…
ERIC Educational Resources Information Center
Nelson, Joseph Derrick
2016-01-01
Background/Context: Positive teacher-student relationships are critical for Black boys' learning across single-sex and coeducational environments. Limited attention to these relationships by school professionals is rooted in deficit-oriented conceptions of boyhood and Black masculinity. The popular message of deficiency and pathology is clear:…
The effects of sex, sexual orientation, and digit ratio (2D:4D) on mental rotation performance.
Peters, Michael; Manning, John T; Reimers, Stian
2007-04-01
In spite of the reduced level of experimental control, this large scale study brought some clarity into the relation between mental rotation task (MRT) performance and a number of variables where contradictory associations had previously been reported in the literature. Clear sex differences in MRT were observed for a sample of 134,317 men and 120,783 women, with men outperforming women. There were also MRT differences as a function of sexual orientation: heterosexual men performed better than homosexual men and homosexual women performed better than heterosexual women. Although bisexual men performed better than homosexual men but less well than heterosexual men, no significant differences were observed between bisexual and homosexual women. MRT performance in both men and women peaked in the 20-30 year range, and declined significantly and markedly thereafter. Both men and women showed a significant negative correlation between left and right digit finger ratio and MRT scores, such that individuals with smaller digit ratios (relatively longer ring finger than index finger) performed better than individuals with larger digit ratios.
Rojo, V; Giovannotti, M; Naveira, H; Nisi Cerioni, P; González-Tizón, A M; Caputo Barucchi, V; Galán, P; Olmo, E; Martínez-Lage, A
2014-01-01
Rock lizards of the genus Iberolacerta constitute a promising model to examine the process of sex chromosome evolution, as these closely related taxa exhibit remarkable diversity in the degree of sex chromosome differentiation with no clear phylogenetic segregation, ranging from cryptic to highly heteromorphic ZW chromosomes and even multiple chromosome systems (Z1Z1Z2Z2/Z1Z2W). To gain a deeper insight into the patterns of karyotype and sex chromosome evolution, we performed a cytogenetic analysis based on conventional staining, banding techniques and fluorescence in situ hybridization in the species I. monticola, for which previous cytogenetic investigations did not detect differentiated sex chromosomes. The karyotype is composed of 2n = 36 acrocentric chromosomes. NORs and the major ribosomal genes were located in the subtelomeric region of chromosome pair 6. Hybridization signals of the telomeric sequences (TTAGGG)n were visualized at the telomeres of all chromosomes and interstitially in 5 chromosome pairs. C-banding showed constitutive heterochromatin at the centromeres of all chromosomes, as well as clear pericentromeric and light telomeric C-bands in several chromosome pairs. These results highlight some chromosomal markers which can be useful to identify species-specific diagnostic characters, although they may not accurately reflect the phylogenetic relationships among the taxa. In addition, C-banding revealed the presence of a heteromorphic ZW sex chromosome pair, where W is smaller than Z and almost completely heterochromatic. This finding sheds light on sex chromosome evolution in the genus Iberolacerta and suggests that further comparative cytogenetic analyses are needed to understand the processes underlying the origin, differentiation and plasticity of sex chromosome systems in lacertid lizards. © 2013 S. Karger AG, Basel.
Bouffard, Jason; Yang, Chen; Begon, Mickael; Côté, Julie
2018-04-19
Muscle fatigue induced by repetitive movements contributes to the development of musculoskeletal disorders. Men and women respond differently to muscle fatigue during isometric single-joint efforts, but sex differences during dynamic multi-joint tasks have not been clearly identified. Moreover, most studies comparing men and women during fatigue development assessed endurance time. However, none evaluated sex differences in kinematic adaptations to fatigue during multi-joint dynamic tasks. The objective of the study was to compare how men and women adapt their upper body kinematics during a fatiguing repetitive pointing task. Forty men and 41 women performed repetitive pointing movements (one per second) between two targets while maintaining their elbow elevated at shoulder height. The task ended when participants rated a perceived level of fatigue of 8/10. Trunk, humerothoracic, and elbow angles were compared between the first and last 30 s of the experiment and between men and women. Linear positions of the index finger (distance from the target) and the elbow (arm elevation) as well as movement timing were documented as task performance measures. Men (7.4 ± 3.2 min) and women (8.3 ± 4.5 min) performed the repetitive pointing task for a similar duration. For both sex groups, trunk range of motion increased with fatigue while shoulder's and elbow's decreased. Moreover, participants modified their trunk posture to compensate for the decreased humerothoracic elevation. Movements at all joints also became more variable with fatigue. However, of the 24 joint angle variables assessed, only two Sex × Fatigue interactions were observed. Although average humerothoracic elevation angle decreased in both subgroups, this decrease was greater in men (standardized response mean [SRM] - 1.63) than in women (SRM - 1.44). Moreover, the movement-to-movement variability of humerothoracic elevation angle increased only in women (SRM 0.42). Despite many similarities between men's and women's response to fatigue induced by repetitive pointing movements, some sex differences were observed. Those subtle differences may indicate that men's shoulder muscles were more fatigued than women's despite a similar level of perceived exertion. They may also indicate that men and women do not adapt the exact same way to a similar fatigue.
Hughes, Travis; Adler, Adam; Merrill, Joan T; Kelly, Jennifer A; Kaufman, Kenneth M; Williams, Adrienne; Langefeld, Carl D; Gilkeson, Gary S; Sanchez, Elena; Martin, Javier; Boackle, Susan A; Stevens, Anne M; Alarcón, Graciela S; Niewold, Timothy B; Brown, Elizabeth E; Kimberly, Robert P; Edberg, Jeffrey C; Ramsey-Goldman, Rosalind; Petri, Michelle; Reveille, John D; Criswell, Lindsey A; Vilá, Luis M; Jacob, Chaim O; Gaffney, Patrick M; Moser, Kathy L; Vyse, Timothy J; Alarcón-Riquelme, Marta E; James, Judith A; Tsao, Betty P; Scofield, R Hal; Harley, John B; Richardson, Bruce C; Sawalha, Amr H
2012-05-01
Systemic lupus erythematosus (SLE) is a sexually dimorphic autoimmune disease which is more common in women, but affected men often experience a more severe disease. The genetic basis of sexual dimorphism in SLE is not clearly defined. A study was undertaken to examine sex-specific genetic effects among SLE susceptibility loci. A total of 18 autosomal genetic susceptibility loci for SLE were genotyped in a large set of patients with SLE and controls of European descent, consisting of 5932 female and 1495 male samples. Sex-specific genetic association analyses were performed. The sex-gene interaction was further validated using parametric and non-parametric methods. Aggregate differences in sex-specific genetic risk were examined by calculating a cumulative genetic risk score for SLE in each individual and comparing the average genetic risk between male and female patients. A significantly higher cumulative genetic risk for SLE was observed in men than in women. (P=4.52x10-8) A significant sex-gene interaction was seen primarily in the human leucocyte antigen (HLA) region but also in IRF5, whereby men with SLE possess a significantly higher frequency of risk alleles than women. The genetic effect observed in KIAA1542 is specific to women with SLE and does not seem to have a role in men. The data indicate that men require a higher cumulative genetic load than women to develop SLE. These observations suggest that sex bias in autoimmunity could be influenced by autosomal genetic susceptibility loci.
Congrains, Carlos; Campanini, Emeline B; Torres, Felipe R; Rezende, Víctor B; Nakamura, Aline M; de Oliveira, Janaína L; Lima, André L A; Chahad-Ehlers, Samira; Sobrinho, Iderval S; de Brito, Reinaldo A
2018-01-01
Several studies have demonstrated that genes differentially expressed between sexes (sex-biased genes) tend to evolve faster than unbiased genes, particularly in males. The reason for this accelerated evolution is not clear, but several explanations have involved adaptive and nonadaptive mechanisms. Furthermore, the differences of sex-biased expression patterns of closely related species are also little explored out of Drosophila. To address the evolutionary processes involved with sex-biased expression in species with incipient differentiation, we analyzed male and female transcriptomes of Anastrepha fraterculus and Anastrepha obliqua, a pair of species that have diverged recently, likely in the presence of gene flow. Using these data, we inferred differentiation indexes and evolutionary rates and tested for signals of selection in thousands of genes expressed in head and reproductive transcriptomes from both species. Our results indicate that sex-biased and reproductive-biased genes evolve faster than unbiased genes in both species, which is due to both adaptive pressure and relaxed constraints. Furthermore, among male-biased genes evolving under positive selection, we identified some related to sexual functions such as courtship behavior and fertility. These findings suggest that sex-biased genes may have played important roles in the establishment of reproductive isolation between these species, due to a combination of selection and drift, and unveil a plethora of genetic markers useful for more studies in these species and their differentiation. © The Author(s) 2018. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.
Hobara, Mieko
2005-08-01
The Appropriate Pain Behavior Questionnaire (APBQ) was employed to examine the effects of the participants' sex and culture on their beliefs regarding gender-appropriate pain behavior. The APBQ examines beliefs about the social acceptability to male and female participants of the behavioral and verbal expressions of pain by men and women (referents) in the presence of others [Nayak, S., 2000. Cross Cult Research 34, 135-151]. The participants were 18 male and 14 female Japanese, and 11 male and 21 female Euro-Americans. There was a significant effect of sex: female participants considered pain behaviors more acceptable than male participants. There was a significant effect of culture: compared to both male and female Japanese, Euro-American participants rated pain behaviors in both sexes to be more acceptable. There was also a significant effect of referent gender: for both sexes in both cultures, pain behaviors in women were rated as more acceptable than in men. Furthermore, a significant interaction was found between referent gender and sex of the participant: Male and female participants of both cultures were equally accepting of pain behaviors in women, but male participants were less accepting of pain behaviors in men than in women. There also was a significant interaction between referent gender and culture of the participant: Japanese participants considered pain behavior in both genders to be less acceptable than did Americans. The results are explained in terms of cultural traditions and social roles, and have clear implications for clinical treatment and diagnosis.
Sex-specific differences in pathogen susceptibility in honey bees (Apis mellifera).
Retschnig, Gina; Williams, Geoffrey R; Mehmann, Marion M; Yañez, Orlando; de Miranda, Joachim R; Neumann, Peter
2014-01-01
Sex-related differences in susceptibility to pathogens are a common phenomenon in animals. In the eusocial Hymenoptera the two female castes, workers and queens, are diploid and males are haploid. The haploid susceptibility hypothesis predicts that haploid males are more susceptible to pathogen infections compared to females. Here we test this hypothesis using adult male (drone) and female (worker) honey bees (Apis mellifera), inoculated with the gut endoparasite Nosema ceranae and/or black queen cell virus (BQCV). These pathogens were chosen due to previously reported synergistic interactions between Nosema apis and BQCV. Our data do not support synergistic interactions between N. ceranae and BQCV and also suggest that BQCV has limited effect on both drone and worker health, regardless of the infection level. However, the data clearly show that, despite lower levels of N. ceranae spores in drones than in workers, Nosema-infected drones had both a higher mortality and a lower body mass than non-infected drones, across all treatment groups, while the mortality and body mass of worker bees were largely unaffected by N. ceranae infection, suggesting that drones are more susceptible to this pathogen than workers. In conclusion, the data reveal considerable sex-specific differences in pathogen susceptibility in honey bees and highlight the importance of ultimate measures for determining susceptibility, such as mortality and body quality, rather than mere infection levels.
Sex-Specific Differences in Pathogen Susceptibility in Honey Bees (Apis mellifera)
Retschnig, Gina; Williams, Geoffrey R.; Mehmann, Marion M.; Yañez, Orlando; de Miranda, Joachim R.; Neumann, Peter
2014-01-01
Sex-related differences in susceptibility to pathogens are a common phenomenon in animals. In the eusocial Hymenoptera the two female castes, workers and queens, are diploid and males are haploid. The haploid susceptibility hypothesis predicts that haploid males are more susceptible to pathogen infections compared to females. Here we test this hypothesis using adult male (drone) and female (worker) honey bees (Apis mellifera), inoculated with the gut endoparasite Nosema ceranae and/or black queen cell virus (BQCV). These pathogens were chosen due to previously reported synergistic interactions between Nosema apis and BQCV. Our data do not support synergistic interactions between N. ceranae and BQCV and also suggest that BQCV has limited effect on both drone and worker health, regardless of the infection level. However, the data clearly show that, despite lower levels of N. ceranae spores in drones than in workers, Nosema-infected drones had both a higher mortality and a lower body mass than non-infected drones, across all treatment groups, while the mortality and body mass of worker bees were largely unaffected by N. ceranae infection, suggesting that drones are more susceptible to this pathogen than workers. In conclusion, the data reveal considerable sex-specific differences in pathogen susceptibility in honey bees and highlight the importance of ultimate measures for determining susceptibility, such as mortality and body quality, rather than mere infection levels. PMID:24465518
Chamizo, V D; Rodríguez, C A; Sánchez, J; Mármol, F
2016-09-01
The effects of early environmental enrichment (EE) and voluntary wheel running on the preference for using a landmark or pool geometry when solving a simple spatial task in adult male and female rats were assessed. After weaning, rats were housed in same-sex pairs in enriched or standard cages (EE and control groups) for two and a half months. Then the rats were trained in a triangular-shaped pool to find a hidden platform whose location was defined in terms of these two sources of information, a landmark outside the pool and a particular corner of the pool. As expected, enriched rats reached the platform faster than control animals, and males and females did not differ. Enriched rats also performed better on subsequent test trials without the platform with the cues individually presented (either pool geometry or landmark). However, on a preference test without the platform, a clear sex difference was found: Females spent more time in an area of the pool that corresponded to the landmark, whereas males spent more time in the distinctive corner of the pool. The present EE protocol did not alter females' preference for the landmark cue. The results agree with the claim that environmental enrichment is a consequence of a reduced anxiety response (measured by thigmotaxis) during cognitive testing. A possible implication of ancestral selection pressures is discussed.
Sex differences in the stress response in SD rats.
Lu, Jing; Wu, Xue-Yan; Zhu, Qiong-Bin; Li, Jia; Shi, Li-Gen; Wu, Juan-Li; Zhang, Qi-Jun; Huang, Man-Li; Bao, Ai-Min
2015-05-01
Sex differences play an important role in depression, the basis of which is an excessive stress response. We aimed at revealing the neurobiological sex differences in the same study in acute- and chronically-stressed rats. Female Sprague-Dawley (SD) rats were randomly divided into 6 groups: chronic unpredictable mild stress (CUMS), acute foot shock (FS) and controls, animals in all 3 groups were sacrificed in proestrus or diestrus. Male SD rats were randomly divided into 3 groups: CUMS, FS and controls. Comparisons were made of behavioral changes in CUMS and control rats, plasma levels of corticosterone (CORT), testosterone (T) and estradiol (E2), and of the hypothalamic mRNA-expression of stress-related molecules, i.e. estrogen receptor α and β, androgen receptor, aromatase, mineralocorticoid receptor, glucocorticoid receptor, corticotropin-releasing hormone, arginine vasopressin and oxytocin. CUMS resulted in disordered estrus cycles, more behavioral and hypothalamic stress-related molecules changes and a stronger CORT response in female rats compared with male rats. Female rats also showed decreased E2 and T levels after FS and CUMS, while male FS rats showed increased E2 and male CUMS rats showed decreased T levels. Stress affects the behavioral, endocrine and the molecular response of the stress systems in the hypothalamus of SD rats in a clear sexual dimorphic way, which has parallels in human data on stress and depression. Copyright © 2015 Elsevier B.V. All rights reserved.
USDA-ARS?s Scientific Manuscript database
Field studies evaluated the relative performance of a clear versus several colored delta traps baited with sex pheromone or a food bait for two key moth pests of stone fruits: oriental fruit moth, Graphollita molesta (Busck); and peach twig borer, Anarsia lineatella Zeller. Preliminary studies found...
Obesity in children with poorly controlled asthma: Sex differences.
Lang, Jason E; Holbrook, Janet T; Wise, Robert A; Dixon, Anne E; Teague, W Gerald; Wei, Christine Y; Irvin, Charles G; Shade, David; Lima, John J
2013-09-01
Obesity increases asthma risk, and may alter asthma severity. In adults, sex appears to modify the effect of obesity on asthma. Among children, the effect of sex on the relationship between obesity and asthma severity remains less clear, particularly when considering race. To determine how obesity affects disease characteristics in a diverse cohort of children with poorly controlled asthma, and if obesity effects are altered by sex. We analyzed 306 children between 6 and 17 years of age with poorly controlled asthma enrolled in a 6-month trial assessing lansoprazole for asthma control. In this secondary analysis, we determined associations between obesity and symptom severity, spirometry, exacerbation risk, airway biomarkers, bronchial reactivity, and airflow perception. We used both a multivariate linear regression and longitudinal mixed-effect model to determine if obesity interacted with sex to affect asthma severity. Regardless of sex, BMI >95th percentile did not affect asthma control, exacerbation risk or airway biomarkers. Sex changed the effect of obesity on lung function (sex × obesity FEV1%, interaction P-value < 0.01, sex × obesity FEV1/FVC, interaction P-value = 0.03). Obese males had significantly worse airflow obstruction compared to non-obese males, while in females there was no obesity effect on airflow obstruction. In females, obesity was associated with significantly greater FEV1 and FVC, and a trend toward reduced airway reactivity. Obesity did not affect asthma control, airway markers or disease stability; however obesity did affect lung function in a sex-dependent manner. In males, obesity associated with reduced FEV1/FVC, and in females, obesity associated with substantially improved lung function. Copyright © 2012 Wiley Periodicals, Inc.
Gender and human rights dimensions of HIV/AIDS in Nigeria.
Aniekwu, Nkoli I
2002-12-01
Until very recently, researchers paid little attention to sex or gender issues in HIV/AIDS. When differences between females and males on health matters were considered at all the focus was clearly on womens' reproductive lives and not on factors affecting the spread of the disease. There was hardly any consideration of the influence of inequalities on the spread of HIV/AIDS and on outcomes of infection between the sexes. Hitherto, health policies and programmes focused on biological aspects of diagnosis, treatment and prevention. In this paper, the author seeks to provide an understanding of the social factors as well as identification of the capacity of human rights to develop an effective response to the disease. It is a gender perspective on human rights with specific implications for women in the context of HIV/AIDS.
Puberty in the Corpus Callosum
Chavarria, Mary C.; Sánchez, Francisco J.; Chou, Yi-Yu; Thompson, Paul M.; Luders, Eileen
2014-01-01
Adolescence is an important period for brain development. White matter growth is influenced by sex hormones such as testosterone, and the corpus callosum—the largest white matter structure in the human brain—may change structurally during the hormone-laden period of adolescence. Little is known about puberty’s relationship to structural brain development, even though pubertal stage may better predict cognitive and behavioral maturity than chronological age. We therefore aimed to establish the presence and direction of pubertal effects on callosal anatomy. For this purpose, we applied advanced surface-based mesh-modeling to map correlations between callosal thickness and pubertal stage in a large and well-matched sample of 124 children and adolescents (62 female and 62 male) aged 5–18 years from a normative database. When linking callosal anatomy to pubertal status, only positive correlations reached statistical significance, indicating that callosal growth advances with puberty. In tests of differences in callosal anatomy at different stages of puberty, callosal growth was concentrated in different locations depending on the pubertal stage. Changing levels of circulating sex hormones during different phases of puberty likely contributed to the observed effects, and further research is clearly needed. Direct quantification of sex hormone levels and regional fiber connectivity—ideally using fiber tractography—will reveal whether hormones are the main drivers of callosal change during puberty. These callosal findings may lead to hypotheses regarding cortical changes during puberty, which may promote or result from changes in interhemispheric connectivity. PMID:24468104
Whiteman, E.A.; Jennings, C.A.; Nemeth, R.S.
2005-01-01
Ultrasonic imaging was used to determine the spawning population structure and develop a fecundity estimation model for a red hind Epinephelus guttatus spawning aggregation within the Red Hind Bank Marine Conservation District, St Thomas, U.S.V.I. The spawning population showed considerable within-month and between-month variation in population size- and sex-structure. In the spawning season studied, males appeared to arrive at the aggregation site first in December although females represented a large proportion of the catch early in the aggregation periods in January and February. Spawning occurred in January and February, and size frequency distributions suggested that an influx of small females occurred during the second spawning month. An overall sex ratio of 2.9:1 (female:male) was recorded for the whole reproductive season. The sex ratio, however, differed between months and days within months. More females per male were recorded in January than in February when the sex ratio was male biased. Fecundity estimates for this species predicted very high potential fecundities (2.4 ?? 105-2.4 ?? 106 oocytes). The ultrasound model also illustrated a rapid increase in potential female fecundity with total length. Ultrasonic imaging may prove a valuable tool in population assessment for many species and locations in which invasive fishing methods are clearly undesirable. ?? 2005 The Fisheries Society of the British Isles.
The evolution of sex roles in birds is related to adult sex ratio.
Liker, András; Freckleton, Robert P; Székely, Tamás
2013-01-01
Sex-role reversal represents a formidable challenge for evolutionary biologists, since it is not clear which ecological, life-history or social factors facilitated conventional sex roles (female care and male-male competition for mates) to be reversed (male care and female-female competition). Classic theories suggested ecological or life-history predictors of role reversal, but most studies failed to support these hypotheses. Recent theory however predicts that sex-role reversal should be driven by male-biased adult sex ratio (ASR). Here we test this prediction for the first time using phylogenetic comparative analyses. Consistent with theory, both mating system and parental care are strongly related to ASR in shorebirds: conventional sex roles are exhibited by species with female-biased ASR, whereas sex-role reversal is associated with male-biased ASR. These results suggest that social environment has a strong influence on breeding systems and therefore revealing the causes of ASR variation in wild populations is essential for understanding sex role evolution.
Augustsson, Hanna; Dahlborn, Kristina; Meyerson, Bengt J
2005-02-15
In an evolutionary prospective, it is possible that female mice have a differential perception of novel events than male mice and use a different behavioural strategy for risk assessment. However, female mice are less studied than male mice in behavioural tests of emotional reactivity. The aim of the present study was to investigate how wild-derived female house mice differ from domesticated female mice in their risk assessment strategy. A total of 46 adult female mice, 14 BALB/c, 16 C57BL/6 and 14 Wild mice were tested in the Concentric Square Field (CSF), Open Field (OF) and Elevated Plus Maze (EPM) at three consecutive days. Parameters from all three tests were categorized according to their relevance to activity, exploration, approach-avoidance and use of open areas-shelter. Principal Component Analysis (PCA-SIMCA) of the animals' behaviour in the CSF arena was performed both for females alone and in comparison with earlier findings in male mice under the same test conditions. The results clearly show that female wild mice had a higher avoidance of open areas than the laboratory strains. There was also a trend indicating differences in exploration and approach-avoidance between female Wild and the laboratory strains. The multivariate test, CSF, was able to detect differences between Wild and laboratory strains in three (exploration, approach-avoidance, open-shelter) of the four functional categories measured. Wild female mice also had a higher frequency of rearing and grooming and a lower duration in the corridors in the CSF. Clear strain differences were found between BALB and C57BL in all tests where BALB generally had higher risk assessment and lower risk taking than C57BL. No general sex differences were found, however the sex differences were greater in Wild mice compared to the laboratory strains.
NASA Astrophysics Data System (ADS)
Brandstetter, Birgit; Ruther, Joachim
2016-06-01
The availability of linoleic acid (LA; C18:2∆9,12) is pivotal for animals. While vertebrates depend on a nutritional supply, some invertebrates, including the parasitic wasp Nasonia vitripennis, are able to synthesize LA from oleic acid (OA; C18:1∆9). This raises the question as to whether these animals nevertheless benefit from the additional uptake of LA with the diet. LA plays an important role in the sexual communication of N. vitripennis because males use it as a precursor for the synthesis of an abdominal sex pheromone attracting virgin females. We reared hosts of N. vitripennis that were fed diets enriched in the availability of stearic acid (SA: C18:0), OA or LA. N. vitripennis males developing on the different host types clearly differed in both the fatty acid composition of their body fat and sex pheromone titres. Males from LA-enriched hosts had an almost fourfold higher proportion of LA and produced significantly more sex pheromone than males from SA (2.2-fold) and OA (1.4-fold) enriched hosts, respectively. Our study demonstrates that animals being able to synthesize important nutrients de novo may still benefit from an additional supply with their diet.
School Subject Preferences of Pupils in Single Sex and Co-educational Secondary Schools.
ERIC Educational Resources Information Center
Colley, Ann; And Others
1994-01-01
Reports on a study of school subject preference among 566 male and 567 female students in both single-sex and coeducational British secondary schools. Finds an effect of school type for younger students only. Also finds clear effects of gender with higher rankings given to mathematics and science by boys and to art by girls. (CFR)
The Pedagogy of (In)Visibility: Two Accounts of Teaching about Sex, Gender, and Sexuality
ERIC Educational Resources Information Center
Miller, Andrea; Lucal, Betsy
2009-01-01
As teachers who use both our theoretical (academic) and practical (empirical) knowledge to entice our students to peer outside of the seemingly clear-cut boxes of the two-and-only-two dichotomies of sex, gender, and sexuality, we attempt to problematize not only sexuality categories but also gender categories (specifically, the category "woman").…
Single-Sex Teaching and Achievement in Science. Research Report
ERIC Educational Resources Information Center
Robinson, W. P.; Gillibrand, E.
2004-01-01
The primary purpose was to investigate the efficacy of a full year of single-sex (SS) teaching of science. The secondary aims were to locate any differentiation by set and gender, and to relate these to more proximal variables. Participants were 13 year olds. Higher set girls gave evidence of clear benefits overall, and higher set boys also,…
The Tribolium castaneum Ortholog of Sex combs reduced Controls Dorsal Ridge Development
Shippy, Teresa D.; Rogers, Carmelle D.; Beeman, Richard W.; Brown, Susan J.; Denell, Robin E.
2006-01-01
In insects, the boundary between the embryonic head and thorax is formed by the dorsal ridge, a fused structure composed of portions of the maxillary and labial segments. However, the mechanisms that promote development of this unusual structure remain a mystery. In Drosophila, mutations in the Hox genes Sex combs reduced and Deformed have been reported to cause abnormal dorsal ridge formation, but the significance of these abnormalities is not clear. We have identified three mutant allele classes of Cephalothorax, the Tribolium castaneum (red flour beetle) ortholog of Sex combs reduced, each of which has a different effect on dorsal ridge development. By using Engrailed expression to monitor dorsal ridge development in these mutants, we demonstrate that Cephalothorax promotes the fusion and subsequent dorsolateral extension of the maxillary and labial Engrailed stripes (posterior compartments) during dorsal ridge formation. Molecular and genetic analysis of these alleles indicates that the N terminus of Cephalothorax is important for the fusion step, but is dispensable for Engrailed stripe extension. Thus, we find that specific regions of Cephalothorax are required for discrete steps in dorsal ridge formation. PMID:16849608
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.
Lu, Xiaonan; Webb, Molly; Talbott, Mariah; Van Eenennaam, Joel; Palumbo, Amanda; Linares-Casenave, Javier; Doroshov, Serge; Struffenegger, Peter; Rasco, Barbara
2010-04-14
Fourier transform infrared spectroscopy (FT-IR, 4000-400 cm(-1)) was applied to blood plasma of farmed white sturgeon (N = 40) to differentiate and predict the stages of ovarian maturity. Spectral features of sex steroids (approximately 3000 cm(-1)) and vitellogenin (approximately 1080 cm(-1)) were identified. Clear segregation of maturity stages (previtellogenesis, vitellogenesis, postvitellogenesis, and follicular atresia) was achieved using principal component analysis (PCA). Progression of oocyte development in the late phase of vitellogenesis was also monitored using PCA based on changes in plasma concentrations of sex steroid and lipid content. The observed oocyte polarization index (PI, a measure of nuclear migration) was correlated with changes in plasma sex steroid levels revealed by FT-IR PCA results. A partial least squares (PLS) model predicted PI values within the range 0.12-0.40 (R = 0.95, SEP = 2.18%) from differences in spectral features. These results suggest that FT-IR may be a good tool for assessing ovarian maturity in farmed sturgeon and will reduce the need for the invasive ovarian biopsy required for PI determination.
Dupuy, Fabienne; Rouyar, Angéla; Deisig, Nina; Bourgeois, Thomas; Limousin, Denis; Wycke, Marie-Anne; Anton, Sylvia; Renou, Michel
2017-01-01
Recognition of intra-specific olfactory signals within a complex environment of plant-related volatiles is crucial for reproduction in male moths. Sex pheromone information is detected by specific olfactory receptor neurons (Phe-ORNs), highly abundant on the male antenna. The information is then transmitted to the pheromone processing macroglomerular complex (MGC) within the primary olfactory center, the antennal lobe, where it is processed by local interneurons and projection neurons. Ultimately a behavioral response, orientation toward the pheromone source, is elicited. Volatile plant compounds (VPCs) are detected by other functional types of olfactory receptor neurons (ORNs) projecting in another area of the antennal lobe. However, Phe-ORNs also respond to some VPCs. Female-produced sex pheromones are emitted within a rich environment of VPCs, some of which have been shown to interfere with the detection and processing of sex pheromone information. As interference between the different odor sources might depend on the spatial and temporal features of the two types of stimuli, we investigated here behavioral and neuronal responses to a brief sex pheromone blend pulse in a VPC background as compared to a control background in the male noctuid moth Agrotis ipsilon . We observed male orientation behavior in a wind tunnel and recorded responses of Phe-ORNs and MGC neurons to a brief sex pheromone pulse within a background of individual VPCs. We also recorded the global input signal to the MGC using in vivo calcium imaging with the same stimulation protocol. We found that VPCs eliciting a response in Phe-ORNs and MGC neurons masked responses to the pheromone and decreased the contrast between background odor and the sex pheromone at both levels, whereas α-pinene did not interfere with first order processing. The calcium signal produced in response to a VPC background was tonic, lasting longer than the VPC stimulus duration, and masked entirely the pheromone response. One percent heptanal and linalool, in addition to the masking effect, caused a clear delay in responses of MGC neurons to the sex pheromone. Upwind flight toward the pheromone in a wind tunnel was also delayed but otherwise not altered by different doses of heptanal.
Wu, Guan-Chung; Tey, Wei-Guan; Li, Hau-Wen; Chang, Ching-Fong
2015-01-01
Androgen administration has been widely used for masculinization in fish. The mechanism of the sex change in sexual fate regulation is not clear. Oral administration or pellet implantation was applied. We orally applied an aromatase inhibitor (AI, to decrease estrogen levels) and 17α-methyltestosterone (MT, to increase androgen levels) to induce masculinization to clarify the mechanism of the sex change in the protogynous orange-spotted grouper. After 3 mo of AI/MT administration, male characteristics were observed in the female-to-male sex change fish. These male characteristics included increased plasma 11-ketotestosterone (11-KT), decreased estradiol (E2) levels, increased male-related gene (dmrt1, sox9, and cyp11b2) expression, and decreased female-related gene (figla, foxl2, and cyp19a1a) expression. However, the reduced male characteristics and male-to-female sex change occurred after AI/MT-termination in the AI- and MT-induced maleness. Furthermore, the MT-induced oocyte-depleted follicle cells (from MT-implantation) had increased proliferating activity, and the sexual fate in a portion of female gonadal soma cells was altered to male function during the female-to-male sex change. In contrast, the gonadal soma cells were not proliferative during the early process of the male-to-female sex change. Additionally, the male gonadal soma cells did not alter to female function during the male-to-female sex change in the AI/MT-terminated fish. After MT termination in the male-to-female sex-changed fish, the differentiated male germ cells showed increased proliferating activities together with dormancy and did not show characteristics of both sexes in the early germ cells. In conclusion, these findings indicate for the first time in a single species that the mechanism involved in the replacement of soma cells is different between the female-to-male and male-to-female sex change processes in grouper. These results also demonstrate that sexual fate determination (secondary sex determination) is regulated by endogenous sex steroid levels.
Wu, Guan-Chung; Tey, Wei-Guan; Li, Hau-Wen; Chang, Ching-Fong
2015-01-01
Androgen administration has been widely used for masculinization in fish. The mechanism of the sex change in sexual fate regulation is not clear. Oral administration or pellet implantation was applied. We orally applied an aromatase inhibitor (AI, to decrease estrogen levels) and 17α-methyltestosterone (MT, to increase androgen levels) to induce masculinization to clarify the mechanism of the sex change in the protogynous orange-spotted grouper. After 3 mo of AI/MT administration, male characteristics were observed in the female-to-male sex change fish. These male characteristics included increased plasma 11-ketotestosterone (11-KT), decreased estradiol (E2) levels, increased male-related gene (dmrt1, sox9, and cyp11b2) expression, and decreased female-related gene (figla, foxl2, and cyp19a1a) expression. However, the reduced male characteristics and male-to-female sex change occurred after AI/MT-termination in the AI- and MT-induced maleness. Furthermore, the MT-induced oocyte-depleted follicle cells (from MT-implantation) had increased proliferating activity, and the sexual fate in a portion of female gonadal soma cells was altered to male function during the female-to-male sex change. In contrast, the gonadal soma cells were not proliferative during the early process of the male-to-female sex change. Additionally, the male gonadal soma cells did not alter to female function during the male-to-female sex change in the AI/MT-terminated fish. After MT termination in the male-to-female sex-changed fish, the differentiated male germ cells showed increased proliferating activities together with dormancy and did not show characteristics of both sexes in the early germ cells. In conclusion, these findings indicate for the first time in a single species that the mechanism involved in the replacement of soma cells is different between the female-to-male and male-to-female sex change processes in grouper. These results also demonstrate that sexual fate determination (secondary sex determination) is regulated by endogenous sex steroid levels. PMID:26714271
2015-05-21
as well as personal, fulfillment.1 However, numerous battles remain before American society reaches true equality between the sexes . The mere...clear that the true intention of feminist theory is to expand options available to both sexes while eliminating gender stratification within society...de Pizan’s attack on sexist clerics in the 15th century is “the first time a woman takes up her pen to defend her sex .”12 She was, however, by no
The effects of energy balance, obesity-proneness and sex on the neuronal response to sweet taste.
Cornier, Marc-Andre; Shott, Megan E; Thomas, Elizabeth A; Bechtell, Jamie L; Bessesen, Daniel H; Tregellas, Jason R; Frank, Guido K
2015-02-01
We have previously shown that propensity for weight gain, energy balance state and sex are important determinants of the neuronal response to visual food cues. It is not clear, though, whether these factors also impact the neuronal response to taste. The objective of this study was to examine the neuronal response to sweet taste during energy imbalance in men and women recruited to be obesity-prone (OP) or obesity-resistant (OR). OP (13 men and 12 women) and OR (12 men and 12 women) subjects were studied after 1 day of eucaloric, overfed and underfed conditions in a randomized crossover design. On each test day, fMRI was performed in the respective acute fed state while subjects received in random order 60 trials each of 1M sucrose solution (SU), or artificial saliva (AS) following a visual cue predicting the taste. The neuronal response to SU versus AS expectation was significantly greater in the amygdala, orbitofrontal cortex, putamen and insula in OR versus OP; SU receipt was not different between groups. There were also sex-based differences with men having greater neuronal response to SU versus AS receipt in the caudate than women. The results, however, were not impacted by the state of energy balance. In summary, response to expectation but not receipt of basic sweet taste was different in OR compared to OP, highlighting the importance of learning and conditioning in the propensity to gain weight. Response to sucrose taste receipt was stronger in men than women, raising questions about the effect of sex hormones on brain response to food. Copyright © 2014 Elsevier B.V. All rights reserved.
Sex Reversal in Reptiles: Reproductive Oddity or Powerful Driver of Evolutionary Change?
Holleley, Clare E; Sarre, Stephen D; O'Meally, Denis; Georges, Arthur
2016-01-01
Is sex a product of genes, the environment, or both? In this review, we describe the diversity of sex-determining mechanisms in reptiles, with a focus on systems that display gene-environment interactions. We summarise the field and laboratory-based evidence for the occurrence of environmental sex reversal in reptiles and ask whether this is a widespread evolutionary mechanism affecting the evolution of sex chromosomes and speciation in vertebrates. Sex determination systems exist across a continuum of genetic and environmental influences, blurring the lines between what was once considered a strict dichotomy between genetic sex determination and temperature-dependent sex determination. Across this spectrum, we identify the potential for sex reversal in species with clearly differentiated heteromorphic sex chromosomes (Pogona vitticeps, Bassiana duperreyi, Eremias multiocellata, Gekko japonicus), weakly differentiated homomorphic sex chromosomes (Niveoscincus ocellatus), and species with only a weak heritable predisposition for sex (Emys orbicularis, Trachemys scripta). We argue that sex reversal is widespread in reptiles (Testudines, Lacertidae, Agamidae, Scincidae, Gekkonidae) and has the potential to have an impact on individual fitness, resulting in reproductively, morphologically, and behaviourally unique phenotypes. Sex reversal is likely to be a powerful evolutionary force responsible for generating and maintaining lability and diversity in reptile sex-determining modes. © 2016 S. Karger AG, Basel.
Sex and vision II: color appearance of monochromatic lights.
Abramov, Israel; Gordon, James; Feldman, Olga; Chavarga, Alla
2012-09-04
Because cerebral cortex has a very large number of testosterone receptors, we examined the possible sex differences in color appearance of monochromatic lights across the visible spectrum. There is a history of men and women perceiving color differently. However, all of these studies deal with higher cognitive functions which may be culture-biased. We study basic visual functions, such as color appearance, without reference to any objects. We present here a detailed analysis of sex differences in primary chromatic sensations. We tested large groups of young adults with normal vision, including spatial and temporal resolution, and stereopsis. Based on standard color-screening and anomaloscope data, we excluded all color-deficient observers. Stimuli were equi-luminant monochromatic lights across the spectrum. They were foveally-viewed flashes presented against a dark background. The elicited sensations were measured using magnitude estimation of hue and saturation. When the only permitted hue terms are red (R) yellow (Y), green (G), blue (B), alone or in combination, such hue descriptions are language-independent and the hue and saturation values can be used to derive a wide range of color-discrimination functions. There were relatively small but clear and significant, differences between males and females in the hue sensations elicited by almost the entire spectrum. Generally, males required a slightly longer wavelength to experience the same hue as did females. The spectral loci of the unique hues are not correlated with anomaloscope matches; these matches are directly determined by the spectral sensitivities of L- and M-cones (genes for these cones are on the X-chromosomes). Nor are there correlations between loci of pairs of unique hues (R, Y, G, B). Wavelength-discrimination functions derived from the scaling data show that males have a broader range of poorer discrimination in the middle of the spectrum. The precise values for all the data depend on whether Newtonian or Maxwellian optics were used, but the sex differences were the same for both optical systems. As with our associated paper on spatio-temporal vision, there are marked sex differences in color vision. The color-appearances we measured are determined by inputs from thalamic neurons (LGN) to individual neurons in primary visual cortex. This convergence from LGN to cortex is guided by the cortex during embryogenesis. We hypothesize that testosterone plays a major role, somehow leading to different connectivities for males and females: color appearance requires a re-combination and re-weighting of neuronal inputs from the LGN to the cortex, which, as we show, depends on the sex of the participant.
Samad, Zainab; Boyle, Stephen; Ersboll, Mads; Vora, Amit N.; Zhang, Ye; Becker, Richard C.; Williams, Redford; Kuhn, Cynthia; Ortel, Thomas L.; Rogers, Joseph G.; O’Connor, Christopher; Velazquez, Eric J.; Jiang, Wei
2016-01-01
BACKGROUND Although emotional stress is associated with ischemic heart disease (IHD) and related clinical events, sex-specific differences in the psychobiological response to mental stress have not been clearly identified. OBJECTIVES We aimed to study the differential psychological and cardiovascular responses to mental stress between male and female patients with stable IHD. METHODS Patients with stable IHD enrolled in the REMIT (Responses of Mental Stress–Induced Myocardial Ischemia to Escitalopram) study underwent psychometric assessments, transthoracic echocardiography, and platelet aggregation studies at baseline and after 3 mental stress tasks. Mental stress–induced myocardial ischemia (MSIMI) was defined as the development or worsening of regional wall motion abnormality, reduction of left ventricular ejection fraction (LVEF) ≥8% by transthoracic echocardiography, and/or ischemic ST-segment change on electrocardiogram during 1 or more of the 3 mental stress tasks. RESULTS In the 310 participants with known IHD (18% women, 82% men), most baseline characteristics were similar between women and men (including heart rate, blood pressure, and LVEF), although women were more likely to be nonwhite, living alone (p < 0.001), and unmarried (p < 0.001); they also had higher baseline depression and anxiety (p < 0.05). At rest, women had heightened platelet aggregation responses to serotonin (p = 0.007) and epinephrine (p = 0.004) compared with men. Following mental stress, women had more MSIMI (57% vs. 41%, p < 0.04), expressed more negative (p = 0.02) and less positive emotion (p < 0.001), and demonstrated higher collagen-stimulated platelet aggregation responses (p = 0.04) than men. Men were more likely than women to show changes in traditional physiological measures, such as blood pressure (p < 0.05) and double product. CONCLUSIONS In this exploratory analysis, we identified clear, measurable, and differential responses to mental stress in women and men. Further studies should test the association of sex differences in cardiovascular and platelet reactivity in response to mental stress and long-term outcomes. (Responses of Myocardial Ischemia to Escitalopram Treatment [REMIT]; NCT00574847) PMID:25323254
Sex-related differences in murine hepatic transcriptional and proteomic responses to TCDD
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prokopec, Stephenie D.; Watson, John D.; Lee, Jamie
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is an environmental contaminant that produces myriad toxicities in most mammals. In rodents alone, there is a huge divergence in the toxicological response across species, as well as among different strains within a species. But there are also significant differences between males and females animals of a single strain. These differences are inconsistent across model systems: the severity of toxicity is greater in female rats than males, while male mice and guinea pigs are more sensitive than females. Because the specific events that underlie this difference remain unclear, we characterized the hepatic transcriptional response of adult male andmore » female C57BL/6 mice to 500 μg/kg TCDD at multiple time-points. The transcriptional profile diverged significantly between the sexes. Female mice demonstrated a large number of altered transcripts as early as 6 h following treatment, suggesting a large primary response. Conversely, male animals showed the greatest TCDD-mediated response 144 h following exposure, potentially implicating significant secondary responses. Nr1i3 was statistically significantly induced at all time-points in the sensitive male animals. This mRNA encodes the constitutive androstane receptor (CAR), a transcription factor involved in the regulation of xenobiotic metabolism, lipid metabolism, cell cycle and apoptosis. Surprisingly though, changes at the protein level (aside from the positive control, CYP1A1) were modest, with only FMO3 showing clear induction, and no genes with sex-differences. Thus, while male and female mice show transcriptional differences in their response to TCDD, their association with TCDD-induced toxicities remains unclear. - Highlights: • Differences exist between the toxicity phenotypes to TCDD in male and female mice. • TCDD-mediated transcriptomic differences were identified between the sexes. • Resistant female mice displayed a large, early-onset, transcriptomic response. • Sensitive male mice displayed a large, late-onset, transcriptomic response. • Fmo2, Fmo3 and Nr1i3 were induced across the time-course in only male mice.« less
[Incidence and follow-up characteristics of neurologically relevant psychogenic symptoms].
Franz, M; Schellberg, D; Reister, G; Schepank, H
1993-06-01
The author reports on the prevalence and stability of the course of neurologically relevant psychogenic symptoms as well as their dependence on age and sex. Altogether 240 probands from the Mannheim Cohort Study on the epidemiology of psychogenic disorders were examined for psychogenic impairment over a 10-year period during three investigation periods. On the whole, seven neurologically relevant groups of symptoms (headache, lumbar and cervical vertebral complaints, non-systematic vertigo, functional hyperkinesia, functional paresis, sleep disturbances, concentration disturbances) differ clearly in frequency, characteristics of the course and clinical relevance.
Code of Federal Regulations, 2014 CFR
2014-07-01
... (Continued) EQUAL EMPLOYMENT OPPORTUNITY COMMISSION GUIDELINES ON DISCRIMINATION BECAUSE OF SEX Pt. 1604, App... prohibits, among other things, discrimination in employment on the basis of sex. The Pregnancy Discrimination Act makes it clear that “because of sex” or “on the basis of sex”, as used in title VII, includes...
Doull, Marion; Welch, Vivian; Puil, Lorri; Runnels, Vivien; Coen, Stephanie E.; Shea, Beverley; O’Neill, Jennifer; Borkhoff, Cornelia; Tudiver, Sari; Boscoe, Madeline
2014-01-01
Background There is increasing recognition of sex/gender differences in health and the importance of identifying differential effects of interventions for men and women. Yet, to whom the research evidence does or does not apply, with regard to sex/gender, is often insufficiently answered. This is also true for systematic reviews which synthesize results of primary studies. A lack of analysis and reporting of evidence on sex/gender raises concerns about the applicability of systematic reviews. To bridge this gap, this pilot study aimed to translate knowledge about sex/gender analysis (SGA) into a user-friendly ‘briefing note’ format and evaluate its potential in aiding the implementation of SGA in systematic reviews. Methods Our Sex/Gender Methods Group used an interactive process to translate knowledge about sex/gender into briefing notes, a concise communication tool used by policy and decision makers. The briefing notes were developed in collaboration with three Cochrane Collaboration review groups (HIV/AIDS, Hypertension, and Musculoskeletal) who were also the target knowledge users of the briefing notes. Briefing note development was informed by existing systematic review checklists, literature on sex/gender, in-person and virtual meetings, and consultation with topic experts. Finally, we held a workshop for potential users to evaluate the notes. Results Each briefing note provides tailored guidance on considering sex/gender to reviewers who are planning or conducting systematic reviews and includes the rationale for considering sex/gender, with examples specific to each review group’s focus. Review authors found that the briefing notes provided welcome guidance on implementing SGA that was clear and concise, but also identified conceptual and implementation challenges. Conclusions Sex/gender briefing notes are a promising knowledge translation tool. By encouraging sex/gender analysis and equity considerations in systematic reviews, the briefing notes can assist systematic reviewers in ensuring the applicability of research evidence, with the goal of improved health outcomes for diverse populations. PMID:25372876
Mate attraction, retention and expulsion.
Miner, Emily J; Shackelford, Todd K
2010-02-01
Sexual selection theory and parental investment theory have guided much of the evolutionary psychological research on human mating. Based on these theories, researchers have predicted and found sex differences in mating preferences and behaviors. Men generally prefer that their long-term partners are youthful and physically attractive. Women generally prefer that their long-term partners have existing resources or clear potential for securing resources and display a willingness to invest those resources in children the relationship might produce. Both men and women, however, desire long-term partners who are kind and intelligent. Once a partner is obtained, men and women act in sex-specific ways to ensure the continuation and exclusivity of the relationship. Men, in particular, engage in behaviors designed to prevent, correct, and anticipate their partner's sexual infidelity. Relationships dissolve for evolutionarily-relevant reasons: infidelity, childlessness, and infertility. The discussion addresses directions for future research.
Vijayakumar, Nandita; Allen, Nicholas B; Youssef, George; Dennison, Meg; Yücel, Murat; Simmons, Julian G; Whittle, Sarah
2016-06-01
What we know about cortical development during adolescence largely stems from analyses of cross-sectional or cohort-sequential samples, with few studies investigating brain development using a longitudinal design. Further, cortical volume is a product of two evolutionarily and genetically distinct features of the cortex - thickness and surface area, and few studies have investigated development of these three characteristics within the same sample. The current study examined maturation of cortical thickness, surface area and volume during adolescence, as well as sex differences in development, using a mixed longitudinal design. 192 MRI scans were obtained from 90 healthy (i.e., free from lifetime psychopathology) adolescents (11-20 years) at three time points (with different MRI scanners used at time 1 compared to 2 and 3). Developmental trajectories were estimated using linear mixed models. Non-linear increases were present across most of the cortex for surface area. In comparison, thickness and volume were both characterised by a combination of non-linear decreasing and increasing trajectories. While sex differences in volume and surface area were observed across time, no differences in thickness were identified. Furthermore, few regions exhibited sex differences in the cortical development. Our findings clearly illustrate that volume is a product of surface area and thickness, with each exhibiting differential patterns of development during adolescence, particularly in regions known to contribute to the development of social-cognition and behavioral regulation. These findings suggest that thickness and surface area may be driven by different underlying mechanisms, with each measure potentially providing independent information about brain development. Hum Brain Mapp 37:2027-2038, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Comparison of the exposure-excretion relationship between men and women exposed to organic solvents.
Kawai, Toshio; Takeuchi, Akito; Ikeda, Masayuki
2015-01-01
The present study was initiated to examine if application of the same biological occupational exposure limits (BOELs) for organic solvents is applicable across the sexes. A survey was conducted in 69 micro-scale enterprises in a furniture-producing industrial park. In practice, 211 men and 52 women participated in the survey. They worked in a series of production process, and were exposed to solvent vapor mixtures. The exposure intensities were monitored with two types of diffusive samplers, one with carbon cloth (for solvents in general) and the other with water (for methyl alcohol) as adsorbents. Solvents in the adsorbents and head-space air from urine samples were analyzed with capillary FID-GC. The measured values were subjected to linear regression analysis followed by statistical evaluation for possible sex-related differences in slopes. Essentially no significant difference was detected between men and women in regression line parameters including slopes. Possible differences in the cases of acetone and toluene were discussed and excluded. With the exceptions for acetone and toluene, the present study did not detect any clear differences between men and women. In examinations of past reports, no support for the observed differences was found. The present findings deserve further study so that a solid conclusion can be formed.
Sex-specific foraging behaviour in a seabird with reversed sexual dimorphism: the red-footed booby.
Weimerskirch, Henri; Le Corre, Matthieu; Ropert-Coudert, Yan; Kato, Akiko; Marsac, Francis
2006-01-01
Most hypotheses attempting to explain the evolution of reversed sexual dimorphism (RSD) assume that size-related differences in foraging ability are of prime importance, but the studies on sex-specific differences in foraging behaviour remain scarce. We compare the foraging behaviour of males and females in a seabird species with a RSD by using several miniaturised activity and telemetry loggers. In red-footed boobies males are 5% smaller and 15% lighter than females, but have a longer tail than females. Both sexes spend similar time on the nest while incubating or brooding. When foraging at sea, males and females spend similar time foraging in oceanic waters, forage in similar areas, spend similar proportion of their foraging trip in flight, and feed on similar prey-flying fishes and flying squids-of similar size. However, compared to males, females range farther during incubation (85 km vs. 50 km), and furthermore feed mostly at the extremity of their foraging trip, whereas males actively forage throughout the trip. Males are much more active than females, landing and diving more often. During the study period, males lost mass, whereas females showed no significant changes. These results indicate that males and females of the red-footed boobies differ in several aspects in their foraging behaviour. Although some differences found in the study may be the direct result of the larger size of females, that is, the slightly higher speeds and deeper depths attained by females, others indicate clearly different foraging strategies between the sexes. The smaller size and longer tail of males confer them a higher agility, and could allow them to occupy a foraging niche different from that of females. The higher foraging effort of males related to its different foraging strategy is probably at the origin of the rapid mass loss of males during the breeding period. These results suggest that foraging differences are probably the reason for the differential breeding investment observed in boobies, and are likely to be involved in the evolution and maintenance of RSD.
Orishimo, Karl F; Liederbach, Marijeanne; Kremenic, Ian J; Hagins, Marshall; Pappas, Evangelos
2014-05-01
The incidence of anterior cruciate ligament (ACL) injuries among dancers is much lower than among team sport athletes, and no clear disparity between sexes has been reported in the dance population. Although numerous studies have observed differences in landing biomechanics of the lower extremity between male and female team sport athletes, there is currently little research examining the landing biomechanics of male and female dancers and none comparing athletes to dancers. Comparing the landing biomechanics within these populations may help explain the lower overall ACL injury rates and lack of sex disparity. The purpose was to compare the effects of sex and group (dancer vs team sport athlete) on single-legged drop-landing biomechanics. The primary hypothesis was that female dancers would perform a drop-landing task without demonstrating typical sex-related risk factors associated with ACL injuries. A secondary hypothesis was that female team sport athletes would display typical ACL risk factors during the same task. Controlled laboratory study. Kinematics and kinetics were recorded as 40 elite modern and ballet dancers (20 men and 20 women) and 40 team sport athletes (20 men and 20 women) performed single-legged drop landings from a 30-cm platform. Joint kinematics and kinetics were compared between groups and sexes with a group-by-sex multivariate analysis of variance (MANOVA) followed by pairwise t tests. Dancers of both sexes and male team sport athletes landed similarly in terms of frontal-plane knee alignment, whereas female team sport athletes landed with a significantly greater peak knee valgus (P = .007). Female dancers were found to have a lower hip adduction torque than those of the other 3 groups (P = .003). Dancers (male and female) exhibited a lower trunk side flexion (P = .002) and lower trunk forward flexion (P = .032) compared with team sport athletes. In executing a 30-cm drop landing, female team sport athletes displayed a greater knee valgus than did the other 3 groups. Dancers exhibited better trunk stability than did athletes. These biomechanical findings may provide insight into the cause of the epidemiological differences in ACL injuries between dancers and athletes and the lack of a sex disparity within dancers.
The thoracic surface anatomy of adult black South Africans: A reappraisal from CT scans.
Keough, N; Mirjalili, S A; Suleman, F E; Lockhat, Z I; van Schoor, A
2016-11-01
Surface landmarks or planes taught in anatomy curricula derive from standard anatomical textbooks. Although many surface landmarks are valid, clear age, sex, and population differences exist. We reappraise the thoracic surface anatomy of black South Africans. We analyzed 76 (female = 42; male = 34) thoracoabdominal CT-scans. Patients were placed in a supine position with arms abducted. We analyzed the surface anatomy of the sternal angle, tracheal, and pulmonary trunk bifurcation, azygos vein termination, central veins, heart apex, diaphragm, xiphisternal joint, and subcostal plane using standardized definitions. Surface anatomy landmarks were mostly within the normal variation limits described in previous studies. Variation was observed where the esophagus (T9) and inferior vena cava (IVC) (T8/T9/T10) passed through the diaphragm. The bifurcations of the trachea and pulmonary trunk were inferior to the sternal angle. The subcostal plane level was positioned at L1/L2. The origin of inferior mesenteric artery was mostly inferior to the subcostal plane. Sex differences were noted for the plane of the xiphisternal joint (P = 0.0082), with males (36%) intersecting at T10 and females (36%) intersecting at T9. We provide further evidence for population variations in surface anatomy. The clinical relevance of surface anatomical landmarks depends on descriptions of normal variation. Accurate descriptions of population, sex, age, and body type differences are essential. Clin. Anat. 29:1018-1024, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Kabat, Geoffrey C; Kim, Mimi Y; Hollenbeck, Albert R; Rohan, Thomas E
2014-12-01
To examine the association of adult height with risk of cancer at different anatomic sites in a cohort of men and women. The association of self-reported height with subsequent cancer risk was assessed in 288,683 men and 192,514 women enrolled in the National Institutes of Health-AARP Diet and Health Study. After a median follow-up of 10.5 years, incident cancer was diagnosed in 51,139 men and 23,407 women. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95 % confidence intervals (95 % CIs) for the association of height with cancer risk. After adjustment for covariates, height was positively associated with increased risk of all cancers combined in both men [HR10 cm increase = 1.05 (95 % CI 1.04-1.06)] and women [HR10 cm increase = 1.08 (95 % CI 1.06-1.10)]. Several sites common to men and women showed significant positive associations with height: colon, rectum, kidney, melanoma, and non-Hodgkin's lymphoma. For other shared sites, the association differed by sex. For still other sites, there was no clear association with height. Positive associations were also observed with cancers of the breast, endometrium, and prostate. Different patterns were observed in the height-cancer association by sex. Studies investigating the biological mechanisms underlying the association of height with cancer risk should focus on those sites that show a reproducible association with attained height.
Sexual selection drives evolution and rapid turnover of male gene expression.
Harrison, Peter W; Wright, Alison E; Zimmer, Fabian; Dean, Rebecca; Montgomery, Stephen H; Pointer, Marie A; Mank, Judith E
2015-04-07
The profound and pervasive differences in gene expression observed between males and females, and the unique evolutionary properties of these genes in many species, have led to the widespread assumption that they are the product of sexual selection and sexual conflict. However, we still lack a clear understanding of the connection between sexual selection and transcriptional dimorphism, often termed sex-biased gene expression. Moreover, the relative contribution of sexual selection vs. drift in shaping broad patterns of expression, divergence, and polymorphism remains unknown. To assess the role of sexual selection in shaping these patterns, we assembled transcriptomes from an avian clade representing the full range of sexual dimorphism and sexual selection. We use these species to test the links between sexual selection and sex-biased gene expression evolution in a comparative framework. Through ancestral reconstruction of sex bias, we demonstrate a rapid turnover of sex bias across this clade driven by sexual selection and show it to be primarily the result of expression changes in males. We use phylogenetically controlled comparative methods to demonstrate that phenotypic measures of sexual selection predict the proportion of male-biased but not female-biased gene expression. Although male-biased genes show elevated rates of coding sequence evolution, consistent with previous reports in a range of taxa, there is no association between sexual selection and rates of coding sequence evolution, suggesting that expression changes may be more important than coding sequence in sexual selection. Taken together, our results highlight the power of sexual selection to act on gene expression differences and shape genome evolution.
A Comparison of Selective Pressures in Plant X-Linked and Autosomal Genes
Krasovec, Marc; Filatov, Dmitry A.
2018-01-01
Selection is expected to work differently in autosomal and X-linked genes because of their ploidy difference and the exposure of recessive X-linked mutations to haploid selection in males. However, it is not clear whether these expectations apply to recently evolved sex chromosomes, where many genes retain functional X- and Y-linked gametologs. We took advantage of the recently evolved sex chromosomes in the plant Silene latifolia and its closely related species to compare the selective pressures between hemizygous and non-hemizygous X-linked genes as well as between X-linked genes and autosomal genes. Our analysis, based on over 1000 genes, demonstrated that, similar to animals, X-linked genes in Silene evolve significantly faster than autosomal genes—the so-called faster-X effect. Contrary to expectations, faster-X divergence was detectable only for non-hemizygous X-linked genes. Our phylogeny-based analyses of selection revealed no evidence for faster adaptation in X-linked genes compared to autosomal genes. On the other hand, partial relaxation of purifying selection was apparent on the X-chromosome compared to the autosomes, consistent with a smaller genetic diversity in S. latifolia X-linked genes (πx = 0.016; πaut = 0.023). Thus, the faster-X divergence in S. latifolia appears to be a consequence of the smaller effective population size rather than of a faster adaptive evolution on the X-chromosome. We argue that this may be a general feature of “young” sex chromosomes, where the majority of X-linked genes are not hemizygous, preventing haploid selection in heterogametic sex. PMID:29751495
A Comparison of Selective Pressures in Plant X-Linked and Autosomal Genes.
Krasovec, Marc; Nevado, Bruno; Filatov, Dmitry A
2018-05-03
Selection is expected to work differently in autosomal and X-linked genes because of their ploidy difference and the exposure of recessive X-linked mutations to haploid selection in males. However, it is not clear whether these expectations apply to recently evolved sex chromosomes, where many genes retain functional X- and Y-linked gametologs. We took advantage of the recently evolved sex chromosomes in the plant Silene latifolia and its closely related species to compare the selective pressures between hemizygous and non-hemizygous X-linked genes as well as between X-linked genes and autosomal genes. Our analysis, based on over 1000 genes, demonstrated that, similar to animals, X-linked genes in Silene evolve significantly faster than autosomal genes—the so-called faster-X effect. Contrary to expectations, faster-X divergence was detectable only for non-hemizygous X-linked genes. Our phylogeny-based analyses of selection revealed no evidence for faster adaptation in X-linked genes compared to autosomal genes. On the other hand, partial relaxation of purifying selection was apparent on the X-chromosome compared to the autosomes, consistent with a smaller genetic diversity in S. latifolia X-linked genes (π x = 0.016; π aut = 0.023). Thus, the faster-X divergence in S. latifolia appears to be a consequence of the smaller effective population size rather than of a faster adaptive evolution on the X-chromosome. We argue that this may be a general feature of “young” sex chromosomes, where the majority of X-linked genes are not hemizygous, preventing haploid selection in heterogametic sex.
Residential Spaces and Timing of First Sexual Intercourse Among Never-Married Youths in Nigeria.
Amoyaw, Jonathan Anim; Luginaah, Isaac
2017-10-01
Youths in sub-Saharan Africa who initiate sex at an early age tend to be more vulnerable to HIV/AIDS and other sexually transmitted diseases because of the lack of accurate knowledge of preventive behaviors. Although sociocultural and economic factors associated with sexual initiation among youths have been studied extensively in Nigeria, little is known about the effect of place-based factors. Rural and urban disparities remain high in Nigeria, and these disparities are reinforced by stark regional inequalities between the north and south. Considering these underlying inequalities, we examined the extent to which rural and urban youths in northern and southern Nigeria differ with regard to the timing of sexual initiation using the 2013 Nigerian Demographic and Health Survey. Results from our event history analyses suggest that never-married male and female youths who lived in the urban north delayed their first sexual intercourse compared with their counterparts in the rural north, but those who lived in the rural south had their first sex earlier. Young males who lived in the urban south also experienced their first sex earlier than their counterparts in the rural north. Surprisingly, educated youths and those who had accurate knowledge about HIV/AIDS transmission experienced their first sex early. Clearly, the timing of sexual initiation among youths varies across different spatial and cultural contexts. Therefore, interventions aimed at discouraging early sexual initiation among young people in Nigeria may need to go beyond merely providing health information and services to addressing the livelihood needs of youths, especially those in rural settings.
Mattila, Aino K; Fagerholm, Riitta; Santtila, Pekka; Miettinen, Päivi J; Taskinen, Seppo
2012-11-01
Gender identity and gender role orientation were assessed in 24 female assigned patients with disorders of sex development. A total of 16 patients were prenatally exposed to androgens, of whom 15 had congenital adrenal hyperplasia and 1 was virilized due to maternal tumor. Eight patients had 46,XY karyotype, of whom 5 had partial and 3 had complete androgen insensitivity syndrome. Gender identity was measured by the 27-item Gender Identity/Gender Dysphoria Questionnaire for Adolescents and Adults with 167 female medical students as controls, and gender role was assessed by the femininity and masculinity subscales of the 30-item Bem Sex Role Inventory with 104 female and 64 male medical students as controls. No patient reached the cutoff for gender identity disorder on the Gender Identity/Gender Dysphoria Questionnaire for Adolescents and Adults. However, patients with 46,XY karyotype demonstrated a somewhat more conflicted gender identity, although the overall differences were relatively small. As to gender role orientation, patients with complete androgen insensitivity syndrome had high scores on the femininity and masculinity scales of the Bem Sex Role Inventory, which made them the most androgynous group. Our findings, although clinically not clear cut, suggest that patients with disorders of sex development are a heterogeneous group regarding gender identity and gender role outcomes, and that this issue should be discussed with the family when treatment plans are made. Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
Sandel, Natalie K; Schatz, Philip; Goldberg, Kenneth B; Lazar, Mary
2017-03-01
Research on the acute effects of a concussion among lacrosse players is limited, and postconcussion patterns between male and female athletes have yet to be clearly established. Differences in the style of play and protective gear worn among male and female lacrosse players potentially confound a direct comparison of sex-based differences in this population. To explore sex-based differences in postconcussive neurocognitive functioning and symptom reporting outcomes in concussed adolescent male and female lacrosse players compared with a group of soccer players. Cohort study; Level of evidence, 3. A total of 224 adolescent lacrosse players (112 male, 112 female) aged 13 to 17 years (mean [±SD] age, 15.43 ± 1.09 years) were included in this study. A comparison group of soccer players was added and matched to lacrosse players based on age and sex to address confounding sport differences in male and female versions of lacrosse. All athletes underwent baseline and postinjury testing within 3 days of an injury using the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) tool. Data were analyzed at baseline using a multivariate analysis of variance (MANOVA) with sport and sex as between-participant factors. A 2 × 2 × 2 mixed-factorial MANOVA was also conducted for sex and sport comparisons at baseline versus after a concussion. Ancillary analyses evaluated sex-based differences in exceeded reliable change indices (RCIs) using an independent-samples t test and established postinjury cutoff scores reflective of a protracted recovery using chi-square tests. All athletes had a significantly worse cognitive profile and greater endorsement of symptoms after an injury ( F 5,216 = 30.30, P < .001, η ρ 2 = .41). Sport yielded a significant main effect ( F 5,216 = 2.36, P = .04, η ρ 2 = .05), but subsequent univariate analyses were nonsignificant ( P > .05) across all neurocognitive and symptom outcome variables. Likewise, there were no significant interaction effects for sport × time ( F 5,216 = 1.46, P = .21, η ρ 2 = .03) or sport × sex × time ( F 5,216 = 2.09, P = .07, η ρ 2 = .05), indicating that lacrosse and soccer players respond similarly on neurocognitive testing and symptom reporting after sustaining a concussion. Regarding sex-based differences, female athletes had a significantly greater neurocognitive decline and increased symptoms after a concussion relative to male athletes, regardless of the sport type (sex × time interaction effect: F 5,216 = 3.86, P = .002, η ρ 2 = .08), with the relationship between concussions and sex demonstrating a medium- to large-sized effect. Female athletes demonstrated a significantly greater number of exceeded RCIs ( t(216.16) = -3.732, P < .001), with 59% of male and 74% of female athletes with at least 1 RCI decline. Approximately 13% of male athletes, compared with 30% of female athletes, demonstrated scores indicative of protracted recovery at a 75% sensitivity (χ 2 (1, N = 224) = 9.43, P = .002). Athletes performed more poorly on computerized cognitive screening tools and reported greater symptoms after an acute concussion relative to their baseline performance. Female sex may be a modifier of an acute concussion outcome, given that female athletes in this study performed significantly worse than male athletes across all neurocognitive measures and reported greater symptoms relative to their baseline testing compared with male athletes, regardless of the sport played. Female athletes were also more likely than male athletes to demonstrate scores on neurocognitive testing that exceeded reliable change cutoffs and were predictive of a protracted recovery. The practical significance of these findings should be further verified by prospective longitudinal research given the medium- to large-sized effect demonstrated for the overall relationship between sex and concussions.
Boyer, Stéphane; Lefort, Marie-Caroline; Nboyine, Jerry; Wratten, Steve D.
2017-01-01
Background Melolonthinae beetles, comprising different white grub species, are a globally-distributed pest group. Their larvae feed on roots of several crop and forestry species, and adults can cause severe defoliation. In New Zealand, the endemic scarab pest Costelytra zealandica (White) causes severe defoliation on different horticultural crops, including grape vines (Vitis vinifera). Understanding flight and landing behaviours of this pest can help inform pest management decisions. Methods Adult beetles were counted and then removed from 96 grape vine plants from 21:30 until 23:00 h, every day from October 26 until December 2, during 2014 and 2015. Also, adults were removed from the grape vine foliage at dusk 5, 10, 15, 20 and 25 min after flight started on 2015. Statistical analyses were performed using generalised linear models with a beta-binomial distribution to analyse proportions and with a negative binomial distribution for beetle abundance. Results By analysing C. zealandica sex ratios during its entire flight season, it is clear that the proportion of males is higher at the beginning of the season, gradually declining towards its end. When adults were successively removed from the grape vines at 5-min intervals after flight activity begun, the mean proportion of males ranged from 6–28%. The male proportion suggests males were attracted to females that had already landed on grape vines, probably through pheromone release. Discussion The seasonal and daily changes in adult C. zealandica sex ratio throughout its flight season are presented for the first time. Although seasonal changes in sex ratio have been reported for other melolonthines, changes during their daily flight activity have not been analysed so far. Sex-ratio changes can have important consequences for the management of this pest species, and possibly for other melolonthines, as it has been previously suggested that C. zealandica females land on plants that produce a silhouette against the sky. Therefore, long-term management might evaluate the effect of different plant heights and architecture on female melolonthine landing patterns, with consequences for male distribution, and subsequently overall damage within horticultural areas. PMID:28462026
González-Chang, Mauricio; Boyer, Stéphane; Lefort, Marie-Caroline; Nboyine, Jerry; Wratten, Steve D
2017-01-01
Melolonthinae beetles, comprising different white grub species, are a globally-distributed pest group. Their larvae feed on roots of several crop and forestry species, and adults can cause severe defoliation. In New Zealand, the endemic scarab pest Costelytra zealandica (White) causes severe defoliation on different horticultural crops, including grape vines ( Vitis vinifera ). Understanding flight and landing behaviours of this pest can help inform pest management decisions. Adult beetles were counted and then removed from 96 grape vine plants from 21:30 until 23:00 h, every day from October 26 until December 2, during 2014 and 2015. Also, adults were removed from the grape vine foliage at dusk 5, 10, 15, 20 and 25 min after flight started on 2015. Statistical analyses were performed using generalised linear models with a beta-binomial distribution to analyse proportions and with a negative binomial distribution for beetle abundance. By analysing C. zealandica sex ratios during its entire flight season, it is clear that the proportion of males is higher at the beginning of the season, gradually declining towards its end. When adults were successively removed from the grape vines at 5-min intervals after flight activity begun, the mean proportion of males ranged from 6-28%. The male proportion suggests males were attracted to females that had already landed on grape vines, probably through pheromone release. The seasonal and daily changes in adult C. zealandica sex ratio throughout its flight season are presented for the first time. Although seasonal changes in sex ratio have been reported for other melolonthines, changes during their daily flight activity have not been analysed so far. Sex-ratio changes can have important consequences for the management of this pest species, and possibly for other melolonthines, as it has been previously suggested that C. zealandica females land on plants that produce a silhouette against the sky. Therefore, long-term management might evaluate the effect of different plant heights and architecture on female melolonthine landing patterns, with consequences for male distribution, and subsequently overall damage within horticultural areas.
In the Pursuit of Sons: Additional Births or Sex-Selective Abortion in Pakistan?
Zaidi, Batool; Morgan, S. Philip
2017-01-01
Even though Pakistan is a highly patriarchal society, it has not featured prominently in studies focusing on sex-selective abortion and sex ratios at birth. But with fertility declining and existing strong son preference—Pakistan has one of the highest desired sex ratios in the world—how will Pakistani families respond? In the pursuit of sons, will they have additional children or resort to sex-selective abortions? Or is there evidence that the pursuit of sons is weakening? Using data from three rounds of the demographic and health survey, we show clear evidence of son preference in fertility intentions, patterns of contraceptive use and parity progression ratios. More specifically, we find pervasive evidence that Pakistanis continue childbearing to have a son, to have more than one son and to have at least one daughter. We do not find consistent and convincing evidence that sex ratios at birth (which indicate sex-selective abortion) are increasing. PMID:28392607
Gerbi, Gemechu B.; Habtemariam, Tsegaye; Tameru, Berhanu; Nganwa, David; Robnett, Vinaida
2012-01-01
Objective To determine if significant differences exist in substance use among people living with HIV/AIDS (PLWHA) before and after establishing their HIV infection status. Method The study participants are HIV positive clients of a community based HIV/AIDS outreach facility located in Montgomery, Alabama. The questionnaire includes demographics, substance use and risky sexual behaviors pertaining to HIV transmission. Each participant completed an anonymous questionnaire. A total of 341 questionnaires were distributed and 326 were fully completed and returned, representing a response rate of 96%. Results Findings revealed a statistically significant difference in alcohol consumption before sex among PLWHA before and after establishing their HIV infection status (p = .001). No significant differences were observed among participants who reported as having used drugs intravenously (p = .89), and among those sharing the same syringe/needle with another person (p = .87) before and after establishing their HIV infection status. Conclusion There is continued substance use and alcohol consumption before sex among PLWHA after establishing their HIV status despite clear evidence of such risky behaviors that could lead to an increase in exposure to HIV. PMID:22623879
Bardella, Vanessa Bellini; Pita, Sebastián; Vanzela, André Luis Laforga; Galvão, Cleber; Panzera, Francisco
2016-10-01
The subfamily Triatominae (Hemiptera, Reduviidae) includes 150 species of blood-sucking insects, vectors of Chagas disease or American trypanosomiasis. Karyotypic information reveals a striking stability in the number of autosomes. However, this group shows substantial variability in genome size, the amount and distribution of C-heterochromatin, and the chromosome positions of 45S rDNA clusters. Here, we analysed the karyotypes of 41 species from six different genera with C-fluorescence banding in order to evaluate the base-pair richness of heterochromatic regions. Our results show a high heterogeneity in the fluorescent staining of the heterochromatin in both autosomes and sex chromosomes, never reported before within an insect subfamily with holocentric chromosomes. This technique allows a clear discrimination of the heterochromatic regions classified as similar by C-banding, constituting a new chromosome marker with taxonomic and evolutionary significance. The diverse fluorescent patterns are likely due to the amplification of different repeated sequences, reflecting an unusual dynamic rearrangement in the genomes of this subfamily. Further, we discuss the evolution of these repeated sequences in both autosomes and sex chromosomes in species of Triatominae.
Frank, Sabrina Nadine; Faust, Steffen; Kalbe, Martin; Trubiroha, Achim; Kloas, Werner; Sures, Bernd
2011-06-01
The activity of hepatic glutathione-S-transferase (GST) was analysed in 3 different fish species with respect to fish sex and infection with parasites. In both sexes of laboratory bred three-spined sticklebacks (Gasterosteus aculeatus) experimentally infected with Schistocephalus solidus (Cestoda), a significantly lower GST-activity was found for infected fish compared to control. After field sampling of roach (Rutilus rutilus) from Lake Müggelsee (MS) and the Reservoir Listertalsperre (LTS), the GST-activity showed significantly lower values for males infected with Ligula intestinalis from MS (25%) and for infected females from LTS (55%). L. intestinalis-infected female chub (Leuciscus cephalus) from LTS also appeared to have a lower GST-activity. Thus, it could be shown that the presence of parasites significantly affects GST-activity in different fish species resulting in a decreased GST-activity due to infection. Our results therefore emphasize the need for more integrative approaches in environmental pollution research to clearly identify the possible effects of parasites in an effort to develop biomarkers for evaluating environmental health.
ERIC Educational Resources Information Center
Younger, Frances
This book is based on the premise that sexual expression is a way for people to show affection and love for one another. The book is divided into six chapters that cover topics related to sexuality and growing up. The sections in each chapter contain questions that preteens and teenagers typically ask and provide clear, unambiguous, and…
Youth Smoking in the Country and in the Military: Findings and Ideas.
1999-01-01
to ask both groups the same question. Smoking Behavior: Navy vs. Civilians Research Triangle Institute provides comparisons standardized for sex ...comparisons standardized for sex , age, education, race/ethnicity, and marital status - 1994 data for civilians and 1995 data for Corps - Smoking in...teenagers (and preteens ) clearly begin smoking at younger ages than other population groups. For teens who were smoking by age 18, the percentages
Sex identification in female crayfish is bimodal
NASA Astrophysics Data System (ADS)
Aquiloni, Laura; Massolo, Alessandro; Gherardi, Francesca
2009-01-01
Sex identification has been studied in several species of crustacean decapods but only seldom was the role of multimodality investigated in a systematic fashion. Here, we analyse the effect of single/combined chemical and visual stimuli on the ability of the crayfish Procambarus clarkii to identify the sex of a conspecific during mating interactions. Our results show that crayfish respond to the offered stimuli depending on their sex. While males rely on olfaction alone for sex identification, females require the combination of olfaction and vision to do so. In the latter, chemical and visual stimuli act as non-redundant signal components that possibly enhance the female ability to discriminate potential mates in the crowded social context experienced during mating period. This is one of the few clear examples in invertebrates of non-redundancy in a bimodal communication system.
Clear, specific information about sexual behavior and its consequences is frequently not provided to adolescents by their families, schools and communities. The "sex education" that many receive comes from misinformed or uninformed peers.
Liu, Hui; Brown, Dustin
2014-01-01
Cigarette smoking has long been a target of public health intervention because it substantially contributes to morbidity and mortality. Individuals in different-sex marriages have lower smoking risk (i.e., prevalence and frequency) than different-sex cohabiters. However, little is known about the smoking risk of individuals in same-sex cohabiting unions. We compare the smoking risk of individuals in different-sex marriages, same-sex cohabiting unions, and different-sex cohabiting unions using pooled cross-sectional data from the 1997–2010 National Health Interview Surveys (N = 168,514). We further examine the role of socioeconomic status (SES) and psychological distress in the relationship between union status and smoking. Estimates from multinomial logistic regression models reveal that same-sex and different-sex cohabiters experience similar smoking risk when compared to one another, and higher smoking risk when compared to the different-sex married. Results suggest that SES and psychological distress factors cannot fully explain smoking differences between the different-sex married and same-sex and different-sex cohabiting groups. Moreover, without same-sex cohabiter’s education advantage, same-sex cohabiters would experience even greater smoking risk relative to the different-sex married. Policy recommendations to reduce smoking disparities among same-sex and different-sex cohabiters are discussed. PMID:25346559
Sex differences in the representation of call stimuli in a songbird secondary auditory area
Giret, Nicolas; Menardy, Fabien; Del Negro, Catherine
2015-01-01
Understanding how communication sounds are encoded in the central auditory system is critical to deciphering the neural bases of acoustic communication. Songbirds use learned or unlearned vocalizations in a variety of social interactions. They have telencephalic auditory areas specialized for processing natural sounds and considered as playing a critical role in the discrimination of behaviorally relevant vocal sounds. The zebra finch, a highly social songbird species, forms lifelong pair bonds. Only male zebra finches sing. However, both sexes produce the distance call when placed in visual isolation. This call is sexually dimorphic, is learned only in males and provides support for individual recognition in both sexes. Here, we assessed whether auditory processing of distance calls differs between paired males and females by recording spiking activity in a secondary auditory area, the caudolateral mesopallium (CLM), while presenting the distance calls of a variety of individuals, including the bird itself, the mate, familiar and unfamiliar males and females. In males, the CLM is potentially involved in auditory feedback processing important for vocal learning. Based on both the analyses of spike rates and temporal aspects of discharges, our results clearly indicate that call-evoked responses of CLM neurons are sexually dimorphic, being stronger, lasting longer, and conveying more information about calls in males than in females. In addition, how auditory responses vary among call types differ between sexes. In females, response strength differs between familiar male and female calls. In males, temporal features of responses reveal a sensitivity to the bird's own call. These findings provide evidence that sexual dimorphism occurs in higher-order processing areas within the auditory system. They suggest a sexual dimorphism in the function of the CLM, contributing to transmit information about the self-generated calls in males and to storage of information about the bird's auditory experience in females. PMID:26578918
Sex differences in the representation of call stimuli in a songbird secondary auditory area.
Giret, Nicolas; Menardy, Fabien; Del Negro, Catherine
2015-01-01
Understanding how communication sounds are encoded in the central auditory system is critical to deciphering the neural bases of acoustic communication. Songbirds use learned or unlearned vocalizations in a variety of social interactions. They have telencephalic auditory areas specialized for processing natural sounds and considered as playing a critical role in the discrimination of behaviorally relevant vocal sounds. The zebra finch, a highly social songbird species, forms lifelong pair bonds. Only male zebra finches sing. However, both sexes produce the distance call when placed in visual isolation. This call is sexually dimorphic, is learned only in males and provides support for individual recognition in both sexes. Here, we assessed whether auditory processing of distance calls differs between paired males and females by recording spiking activity in a secondary auditory area, the caudolateral mesopallium (CLM), while presenting the distance calls of a variety of individuals, including the bird itself, the mate, familiar and unfamiliar males and females. In males, the CLM is potentially involved in auditory feedback processing important for vocal learning. Based on both the analyses of spike rates and temporal aspects of discharges, our results clearly indicate that call-evoked responses of CLM neurons are sexually dimorphic, being stronger, lasting longer, and conveying more information about calls in males than in females. In addition, how auditory responses vary among call types differ between sexes. In females, response strength differs between familiar male and female calls. In males, temporal features of responses reveal a sensitivity to the bird's own call. These findings provide evidence that sexual dimorphism occurs in higher-order processing areas within the auditory system. They suggest a sexual dimorphism in the function of the CLM, contributing to transmit information about the self-generated calls in males and to storage of information about the bird's auditory experience in females.
Lu, Yuan; Ding, Qinglan; Xu, Xiao; Spatz, Erica S; Dreyer, Rachel P; D'Onofrio, Gail; Caulfield, Michael; Nasir, Khurram; Spertus, John A; Krumholz, Harlan M
2018-05-30
Young women (aged ≤55 years) with acute myocardial infarction (AMI) have poorer health status outcomes than similarly aged men. Low omega-3 fatty acids (FAs) have been implicated as risk factors for cardiovascular outcomes in AMI patients, but it is not clear whether young women have similar or different post-AMI omega-3 FA profiles compared with young men. We assessed the sex differences in post-AMI omega-3 FAs and the associations of these biomarkers with patient-reported outcomes (symptom, functioning status, and quality of life) at 12-month follow-up, using data from 2985 US adults with AMI aged 18 to 55 years enrolled in the VIRGO (Variation in Recovery: Role of Gender on Outcomes of Young Acute Myocardial Infarction Patients) study. Biomarkers including eicosapentaenoic acid, docosahexaenoic acid, arachidonic acid (AA), eicosapentaenoic acid/AA ratio, omega-3/omega-6 ratio, and omega-3 index were measured 1 month after AMI. Overall, the omega-3 FAs and AA were similar in young men and women with AMI. In both unadjusted and adjusted analysis (controlling for age, sex, race, smoking, hypertension, diabetes mellitus, body mass index, and health status score at 1 month), omega-3 FAs and AA were not significantly associated with 12-month health status scores using the Bonferroni corrected statistical threshold. We found no evidence of sex differences in omega-3 FAs and AA in young men and women 1 month after AMI. Omega-3 FAs and AA at 1-month after AMI were generally not associated with 12-month patient-reported health status after adjusting for patient demographic, clinical characteristics, and the corresponding 1-month health status score. © 2018 The Authors and Quest Diagnostics Inc. Published on behalf of the American Heart Association, Inc., by Wiley.
Červenka, Luděk; Škaroupková, Petra; Kompanowska-Jezierska, Elzbieta; Sadowski, Janusz
2016-10-01
The role of hypertension and the renin-angiotensin system (RAS) in sex-related differences in the course of chronic kidney disease (CKD) and congestive heart failure (CHF) remain unclear, especially when the two diseases are combined. In male and female Ren-2 transgenic rats (TGR), a model of hypertension with activation of endogenous RAS, CKD was induced by 5/6 renal mass reduction (5/6 NX) and CHF was elicited by volume overload achieved by creation of an aorto-caval fistula (ACF). The primary aim of the study was to examine long-term CKD- and CHF-related mortality, especially in animals with CKD and CHF combined, with particular interest in the potential sex-related differences. The follow-up period was 23 weeks after the first intervention (5/6 NX). We found, first, that TGR did not exhibit sexual dimorphism in the course of 5/6 NX-induced CKD. Second, in contrast, TGR exhibited important sex-related differences in the course of ACF-induced CHF-related mortality: intact female TGR showed higher survival rate than male TGR. This situation is reversed in the course of combined 5/6 NX-induced CKD and ACF-induced CHF-related mortality: intact female TGR exhibited poorer survival than male TGR. Third, the survival rate in animals with combined 5/6 NX-induced CKD and ACF-induced CHF was significantly worsened as compared with rat groups that were exposed to 'single organ disease'. Collectively, our present results clearly show that CKD aggravates long-term mortality of animals with CHF. In addition, TGR exhibit remarkable sexual dimorphism with respect to CKD- and CHF-related mortality, especially in animals with combined CKD and CHF. © 2016 John Wiley & Sons Australia, Ltd.
Gast, G C M; Gast, G-C M; Frenken, F J M; van Leest, L A T M; Wendel-Vos, G C W; Bemelmans, W J E
2007-03-01
To investigate time trends in overweight and Leisure Time Physical Activities (LTPA) in The Netherlands since 1980. Intra-national differences were examined stratified for sex, age and urbanisation degree. We used a random sample of about 140,000 respondents aged 20-69 years from the Health Interview Survey (Nethhis) and subsequent Permanent Survey on Living Conditions (POLS). Self-reported data on weight and height and demographic characteristics were gathered through interviews (every year) and data on LTPA were collected by self-administered questionnaires (1990-1997, 2001-2004). Linear regression analysis was performed for trend analyses. During 1981-2004, mean body mass index (BMI) increased significantly by 1.0 kg/m(2) (average per year=0.05 kg/m(2)). Trends were similar across sex and different degrees of urbanisation, but varied across age groups. In 20-to 39-year-old women, mean BMI increased by 1.7 kg/m(2), which was more than in older age groups (P
Unraveling the Sex Chromosome Heteromorphism of the Paradoxical Frog Pseudis tocantins
Gatto, Kaleb Pretto; Busin, Carmen Silvia; Lourenço, Luciana Bolsoni
2016-01-01
The paradoxical frog Pseudis tocantins is the only species in the Hylidae family with known heteromorphic Z and W sex chromosomes. The Z chromosome is metacentric and presents an interstitial nucleolar organizer region (NOR) on the long arm that is adjacent to a pericentromeric heterochromatic band. In contrast, the submetacentric W chromosome carries a pericentromeric NOR on the long arm, which is adjacent to a clearly evident heterochromatic band that is larger than the band found on the Z chromosome and justify the size difference observed between these chromosomes. Here, we provide evidence that the non-centromeric heterochromatic bands in Zq and Wq differ not only in size and location but also in composition, based on comparative genomic hybridization (CGH) and an analysis of the anuran PcP190 satellite DNA. The finding of PcP190 sequences in P. tocantins extends the presence of this satellite DNA, which was previously detected among Leptodactylidae and Hylodidae, suggesting that this family of repetitive DNA is even older than it was formerly considered. Seven groups of PcP190 sequences were recognized in the genome of P. tocantins. PcP190 probes mapped to the heterochromatic band in Wq, and a Southern blot analysis indicated the accumulation of PcP190 in the female genome of P. tocantins, which suggests the involvement of this satellite DNA in the evolution of the sex chromosomes of this species. PMID:27214234
Forewing structure of the solitary bee Osmia bicornis developing on heavy metal pollution gradient.
Szentgyörgyi, Hajnalka; Moroń, Dawid; Nawrocka, Anna; Tofilski, Adam; Woyciechowski, Michał
2017-10-01
Wild bees in natural conditions can develop under various environmental stressors. Heavy metal pollution of the environment is one of the most widely studied stressors in insects, yet its effect is poorly described in bees. We have measured how pollution of the environment along a zinc, cadmium and lead contamination gradient in Poland affects bee development, using red mason bees (Osmia bicornis) as a model and their forewing asymmetry measures to assess possible developmental instabilities. We have also described wing asymmetry measures in the red mason bee-an important managed pollinator species-for the first time. The development of bee larvae in a contaminated environment did not affect forewing asymmetry measures, but it did lead to a negative correlation of wing size with contamination in females. Bees also showed a clear change in their asymmetry measures between various seasons, suggesting other, unknown environmental factors affecting wing asymmetry more than pollution. Sexes were found to have different forewing shape and size, larger females having larger forewings than the smaller males. The direction of size asymmetry was in favour of the left side in both sexes and also shape differences between the left and right wings showed similar tendencies in males and females. The levels of forewing shape and size asymmetry were smaller in females, making them the more symmetrical sex.
Gender-related Differences in Food Craving and Obesity
Hallam, Jessica; Boswell, Rebecca G.; DeVito, Elise E.; Kober, Hedy
2016-01-01
Food craving is often defined as a strong desire to eat. Much work has shown that it consistently and prospectively predicts eating and weight-related outcomes, contributing to the growing obesity epidemic. Although there are clear gender differences in the prevalence and health consequences of obesity, relatively little recent work has investigated gender differences in craving, or any sex-hormone-based differences as they relate to phases of the menstrual cycle. Here, we propose that gender-related differences in food craving contribute to gender-related differences in obesity. Drawing on findings in the addiction literature, we highlight ways to incorporate gender-based differences in food craving into treatment approaches, potentially improving the efficacy of obesity and weight loss treatment. Overall, this review aims to emphasize the importance of investigating gender differences in food craving, with a view towards informing the development of more effective treatments for obesity and weight loss. PMID:27354843
NASA Astrophysics Data System (ADS)
Smith, David R. R.; Patterson, Roy D.
2005-11-01
Glottal-pulse rate (GPR) and vocal-tract length (VTL) are related to the size, sex, and age of the speaker but it is not clear how the two factors combine to influence our perception of speaker size, sex, and age. This paper describes experiments designed to measure the effect of the interaction of GPR and VTL upon judgements of speaker size, sex, and age. Vowels were scaled to represent people with a wide range of GPRs and VTLs, including many well beyond the normal range of the population, and listeners were asked to judge the size and sex/age of the speaker. The judgements of speaker size show that VTL has a strong influence upon perceived speaker size. The results for the sex and age categorization (man, woman, boy, or girl) show that, for vowels with GPR and VTL values in the normal range, judgements of speaker sex and age are influenced about equally by GPR and VTL. For vowels with abnormal combinations of low GPRs and short VTLs, the VTL information appears to decide the sex/age judgement.
Gender Nonconformity, Sexual Orientation, and Dutch Adolescents' Relationship with Peers.
Bos, Henny; Sandfort, Theo
2015-07-01
Same-sex attraction and gender nonconformity have both been shown to negatively affect the relationships of adolescents with their peers. It is not clear, though, whether same-sex attracted adolescents are more likely to have negative peer relationships because they are same-sex attracted or because they are more likely to be gender nonconforming. It is also possible that both stressors affect peer relationships independently or amplify each other in their impact. We explored these questions in a sample of 486 Dutch adolescents (M age = 14.02 years). We found that same-sex attraction and gender nonconformity both had an independent effect and that gender nonconformity moderated, but not mediated, the associations between same-sex attraction and peer relationships at school. Same-sex attraction was more strongly associated with poorer relationships with peers in adolescents who were more gender nonconforming. These findings indicate the importance of including gender nonconformity in the understanding of same-sex attracted adolescents' relationships and suggest that in order to improve same-sex attracted adolescents' social position at school, acceptance of gender diversity should be promoted as well.
Gender Nonconformity, Sexual Orientation, and Dutch Adolescents’ Relationship with Peers
Bos, Henny; Sandfort, Theo
2017-01-01
Same-sex attraction and gender nonconformity have both been shown to negatively affect the relationships of adolescents with their peers. It is not clear, though, whether same-sex attracted adolescents are more likely to have negative peer relationships because they are same-sex attracted or because they are more likely to be gender nonconforming. It is also possible that both stressors affect peer relationships independently or amplify each other in their impact. We explored these questions in a sample of 486 Dutch adolescents (M age = 14.02 years). We found that same-sex attraction and gender nonconformity both had an independent effect and that gender nonconformity moderated, but not mediated, the associations between same-sex attraction and peer relationships at school. Same-sex attraction was more strongly associated with poorer relationships with peers in adolescents who were more gender nonconforming. These findings indicate the importance of including gender nonconformity in the understanding of same-sex attracted adolescents’ relationships and suggest that in order to improve same-sex attracted adolescents’ social position at school, acceptance of gender diversity should be promoted as well. PMID:25548066
Hübner, Lena; Pennings, Steven C; Zimmer, Martin
2015-08-01
Distinct habitats are often linked through fluxes of matter and migration of organisms. In particular, intertidal ecotones are prone to being influenced from both the marine and the terrestrial realms, but whether or not small-scale migration for feeding, sheltering or reproducing is detectable may depend on the parameter studied. Within the ecotone of an upper saltmarsh in the United States, we investigated the sex-specific movement of the semi-terrestrial crab Armases cinereum using an approach of determining multiple measures of across-ecotone migration. To this end, we determined food preference, digestive abilities (enzyme activities), bacterial hindgut communities (genetic fingerprint), and the trophic position of Armases and potential food sources (stable isotopes) of males versus females of different sub-habitats, namely high saltmarsh and coastal forest. Daily observations showed that Armases moved frequently between high-intertidal (saltmarsh) and terrestrial (forest) habitats. Males were encountered more often in the forest habitat, whilst gravid females tended to be more abundant in the marsh habitat but moved more frequently. Food preference was driven by both sex and habitat. The needlerush Juncus was preferred over three other high-marsh detrital food sources, and the periwinkle Littoraria was the preferred prey of male (but not female) crabs from the forest habitats; both male and female crabs from marsh habitat preferred the fiddler crab Uca over three other prey items. In the field, the major food sources were clearly vegetal, but males have a higher trophic position than females. In contrast to food preference, isotope data excluded Uca and Littoraria as major food sources, except for males from the forest, and suggested that Armases consumes a mix of C4 and C3 plants along with animal prey. Digestive enzyme activities differed significantly between sexes and habitats and were higher in females and in marsh crabs. The bacterial hindgut community differed significantly between sexes, but habitat effects were greater than sex effects. By combining multiple measures of feeding ecology, we demonstrate that Armases exhibits sex-specific habitat choice and food preference. By using both coastal forest and saltmarsh habitats, but feeding predominantly in the latter, they possibly act as a key biotic vector of spatial subsidies across habitat borders. The degree of contributing to fluxes of matter, nutrients and energy, however, depends on their sex, indicating that changes in population structure would likely have profound effects on ecosystem connectivity and functioning.
Manchanda, Samiksha; Saikia, Bedangshu; Gupta, Neeraj; Chowdhary, Sona; Puliyel, Jacob M
2011-01-01
Sex-ratio at birth in families with previous girls is worse than those with a boy. Our aim was to prospectively study in a large maternal and child unit sex-ratio against previous birth sex and use of traditional medicines for sex selection. Sex-ratio among mothers in families with a previous girl and in those with a previous boy, prevalence of indigenous medicine use and sex-ratio in those using medicines for sex selection. Overall there were 806 girls to 1000 boys. The sex-ratio was 720:1000 if there was one previous girl and 178:1000 if there were two previous girls. In second children of families with a previous boy 1017 girls were born per 1000 boys. Sex-ratio in those with one previous girl, who were taking traditional medicines for sex selection, was 928:1000. Evidence from the second children clearly shows the sex-ratio is being manipulated by human interventions. More mothers with previous girls tend to use traditional medicines for sex selection, in their subsequent pregnancies. Those taking such medication do not seem to be helped according to expectations. They seem to rely on this method and so are less likely use more definitive methods like sex selective abortions. This is the first such prospective investigation of sex ratio in second children looked at against the sex of previous children. More studies are needed to confirm the findings.
The impact of prescription opioids on all-cause mortality in Canada.
Imtiaz, Sameer; Rehm, Jürgen
2016-08-01
An influential study from the United States generated considerable discussion and debate. This study documented rising morbidity and mortality in midlife among white non-Hispanic Americans in the 21st century, with clear linkages of all-cause mortality to increasing rates of poisonings, suicides and chronic liver disease deaths. All of these causes of deaths are strongly related to the use of legal and illegal substances, but the study stressed the importance of prescription opioids. Given the similarities between the United States and Canada in prescription opioid use, the assessment of similar all-cause mortality trends is relevant for Canada. As this commentary highlights, the all-cause mortality shifts seen in the United States cannot be seen in Canada for either sex or age groups. The exact reasons for the differences between the two countries are not clear, but it is important for public health to further explore this question.
Yuan, Shuai; Xue, Hong-Liang; Yu, Hong-Jie; Huang, Yao; Tang, Bo-Wen; Yang, Xu-Hao; Li, Qing-Xiao; He, Qi-Qiang
2018-06-13
Few studies have investigated the effect of smoking on type 2 diabetes in women compared with men, even though several epidemiological studies provided a clear picture of the risk among the entire population. We systematically searched PubMed and Embase up to August 2017 for prospective studies that were stratified by sex with measures of the relative risk (RR) for type 2 diabetes and current smoking compared with non-smoking. The sex-specific RRs and their ratios (RRRs), comparing women with man, were pooled using random-effects models. Seventeen articles were identified including 20 prospective cohorts with 5 077 289 participants and 223 084 incident cases of type 2 diabetes. The pooled RRR suggested a similar risk of type 2 diabetes associated with smoking in women compared with men (RRR: 0.98, 95% confidence interval [CI]: 0.96-1.01). Furthermore, no significant sex difference in the RR was found between former smokers and those who had never smoked (RRR: 0.98, 95% CI: 0.92-1.04). The findings of this meta-analysis indicate that female smokers had similar risk of type 2 diabetes with male smokers.
Mann, Rajinder S; Rouseff, Russell L; Smoot, Jack; Rao, Nandikeswara; Meyer, Wendy L; Lapointe, Stephen L; Robbins, Paul S; Cha, Dong; Linn, Charles E; Webster, Francis X; Tiwari, Siddharth; Stelinski, Lukasz L
2013-06-01
Huanglongbing (HLB) is the most destructive disease of citrus worldwide. The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is the vector of the phloem-inhabiting bacterium, Candidatus Liberibacter asiaticus, which is presumed to cause HLB in Florida citrus. Laboratory and field studies were conducted to examine the behavioral responses of male and female D. citri to their cuticular extracts. In olfactometer assays, more male D. citri were attracted to one, five, or 10 female cuticular extract equivalent units than blank controls. The results were confirmed in field studies in which clear or yellow traps baited with 10 female cuticular extract equivalent units attracted proportionately more males than clear traps baited with male cuticular extract or unbaited traps. Analyses of cuticular constituents of male and female D. citri revealed differences between the sexes in chemical composition of their cuticular extracts. Laboratory bioassays with synthetic chemicals identified from cuticular extracts indicated that dodecanoic acid attracted more males than clean air. Traps baited with dodecanoic acid did not increase total catch of D. citri as compared with blank traps at the dosages tested; however, the sex ratio of psyllid catch was male biased on traps baited with the highest lure loading dosage tested (10.0 mg). © 2012 The Authors Insect Science © 2012 Institute of Zoology, Chinese Academy of Sciences.
Masculinization of Gene Expression Is Associated with Exaggeration of Male Sexual Dimorphism
Pointer, Marie A.; Harrison, Peter W.; Wright, Alison E.; Mank, Judith E.
2013-01-01
Gene expression differences between the sexes account for the majority of sexually dimorphic phenotypes, and the study of sex-biased gene expression is important for understanding the genetic basis of complex sexual dimorphisms. However, it has been difficult to test the nature of this relationship due to the fact that sexual dimorphism has traditionally been conceptualized as a dichotomy between males and females, rather than an axis with individuals distributed at intermediate points. The wild turkey (Meleagris gallopavo) exhibits just this sort of continuum, with dominant and subordinate males forming a gradient in male secondary sexual characteristics. This makes it possible for the first time to test the correlation between sex-biased gene expression and sexually dimorphic phenotypes, a relationship crucial to molecular studies of sexual selection and sexual conflict. Here, we show that subordinate male transcriptomes show striking multiple concordances with their relative phenotypic sexual dimorphism. Subordinate males were clearly male rather than intersex, and when compared to dominant males, their transcriptomes were simultaneously demasculinized for male-biased genes and feminized for female-biased genes across the majority of the transcriptome. These results provide the first evidence linking sexually dimorphic transcription and sexually dimorphic phenotypes. More importantly, they indicate that evolutionary changes in sexual dimorphism can be achieved by varying the magnitude of sex-bias in expression across a large proportion of the coding content of a genome. PMID:23966876
Masculinization of gene expression is associated with exaggeration of male sexual dimorphism.
Pointer, Marie A; Harrison, Peter W; Wright, Alison E; Mank, Judith E
2013-01-01
Gene expression differences between the sexes account for the majority of sexually dimorphic phenotypes, and the study of sex-biased gene expression is important for understanding the genetic basis of complex sexual dimorphisms. However, it has been difficult to test the nature of this relationship due to the fact that sexual dimorphism has traditionally been conceptualized as a dichotomy between males and females, rather than an axis with individuals distributed at intermediate points. The wild turkey (Meleagris gallopavo) exhibits just this sort of continuum, with dominant and subordinate males forming a gradient in male secondary sexual characteristics. This makes it possible for the first time to test the correlation between sex-biased gene expression and sexually dimorphic phenotypes, a relationship crucial to molecular studies of sexual selection and sexual conflict. Here, we show that subordinate male transcriptomes show striking multiple concordances with their relative phenotypic sexual dimorphism. Subordinate males were clearly male rather than intersex, and when compared to dominant males, their transcriptomes were simultaneously demasculinized for male-biased genes and feminized for female-biased genes across the majority of the transcriptome. These results provide the first evidence linking sexually dimorphic transcription and sexually dimorphic phenotypes. More importantly, they indicate that evolutionary changes in sexual dimorphism can be achieved by varying the magnitude of sex-bias in expression across a large proportion of the coding content of a genome.
Emotional and sexual jealousy as a function of sex and sexual orientation in a Brazilian sample.
de Souza, Altay Alves Lino; Verderane, Michele Pereira; Taira, Juliana Tieme; Otta, Emma
2006-04-01
The goal of the present study was to compare the relative distress of homosexual and heterosexual Brazilian men and women on scenarios in which they imagined their partners sexually or emotionally involved with another person, using a forced-choice paradigm and continuous measures. Participants were 68 heterosexual men, 72 heterosexual women, 42 homosexual men, and 35 homosexual women. On the forced-choice questions heterosexual men (39 on one question and 37 on the other) were more upset than their female counterparts (21 on one question and 15 on the other) by scenarios of sexual infidelity than those of emotional infidelity. On questions using continuous measures no significant difference was found between pleasurable sex and attachment scenarios for heterosexual women or heterosexual men. On the highly upsetting scenarios heterosexual men discriminated between flirting and both pleasurable sex and attachment scenarios, being less disturbed by the former. In contrast, heterosexual women were equally distressed by the three scenarios. Scores for the homosexual men and homosexual women fell in between those of the heterosexual men and heterosexual women and did not show a clear cut preference for the sexual infidelity or the emotional alternative on the forced-choice paradigm. However, on the continuous measures of jealousy homosexuals resembled heterosexuals of the opposite sex. There was no evidence that jealousy would be less intense among homosexuals although reproductive outcomes were not at risk.
Wallis, M C; Waters, P D; Delbridge, M L; Kirby, P J; Pask, A J; Grützner, F; Rens, W; Ferguson-Smith, M A; Graves, J A M
2007-01-01
In eutherian ('placental') mammals, sex is determined by the presence or absence of the Y chromosome-borne gene SRY, which triggers testis determination. Marsupials also have a Y-borne SRY gene, implying that this mechanism is ancestral to therians, the SRY gene having diverged from its X-borne homologue SOX3 at least 180 million years ago. The rare exceptions have clearly lost and replaced the SRY mechanism recently. Other vertebrate classes have a variety of sex-determining mechanisms, but none shares the therian SRY-driven XX female:XY male system. In monotreme mammals (platypus and echidna), which branched from the therian lineage 210 million years ago, no orthologue of SRY has been found. In this study we show that its partner SOX3 is autosomal in platypus and echidna, mapping among human X chromosome orthologues to platypus chromosome 6, and to the homologous chromosome 16 in echidna. The autosomal localization of SOX3 in monotreme mammals, as well as non-mammal vertebrates, implies that SRY is absent in Prototheria and evolved later in the therian lineage 210-180 million years ago. Sex determination in platypus and echidna must therefore depend on another male-determining gene(s) on the Y chromosomes, or on the different dosage of a gene(s) on the X chromosomes.
Landgraeber, Stefan; Samelko, Lauryn; McAllister, Kyron; Putz, Sebastian; Jacobs, Joshua.J.; Hallab, Nadim James
2018-01-01
Background: The rate of revision for some designs of total hip replacements due to idiopathic aseptic loosening has been reported as higher for women. However, whether this is environmental or inherently sex-related is not clear. Objective: Can particle induced osteolysis be sex dependent? And if so, is this dependent on the type of implant debris (e.g. metal vs polymer)? The objective of this study was to test for material dependent inflammatory osteolysis that may be linked to sex using CoCrMo and implant grade conventional polyethylene (UHMWPE), using an in vivo murine calvaria model. Methods: Healthy 12 week old female and male C57BL/6J mice were treated with UHMWPE (1.0um ECD) or CoCrMo particles (0.9um ECD) or received sham surgery. Bone resorption was assessed by micro-computed tomography, histology and histomorphometry on day 12 post challenge. Results: Female mice that received CoCrMo particles showed significantly more inflammatory osteolysis and bone destruction compared to the females who received UHMWPE implant debris. Moreover, females challenged with CoCrMo particles exhibited 120% more inflammatory bone loss compared to males (p<0.01) challenged with CoCrMo implant debris (but this was not the case for UHMWPE particles). Conclusion: We demonstrated sex-specific differences in the amount of osteolysis resulting from CoCrMo particle challenge. This suggests osteo-immune responses to metal debris are preferentially higher in female compared to male mice, and supports the contention that there may be inherent sex related susceptibility to some types of implant debris. PMID:29785221
van Tetering, Marleen A J; Jolles, Jelle
2017-01-01
Executive functions (EFs) develop over the period of early childhood and adolescence up until young adulthood. Individual children differ substantially in the pace at which their EFs develop, and characteristics such as sex and the level of parental education (LPE) are thought to contribute to these differences. In the present study, we assessed age-related changes in EFs as perceived and evaluated by teachers and parents as well as the influence of sex and LPE on their evaluations. We used a newly developed observer-report questionnaire, the Amsterdam Executive Function Inventory (AEFI). The AEFI assesses three important components of the executive aspects of daily life behavior in 13 questions: Attention; Self-control and Self-monitoring; and Planning and Initiative taking. Teachers and parents evaluated these aspects of executive functioning in 186 schoolchildren in grades 3-6 (age: 9-12 years). Age effects within grades and differences in social economic status between the four participating schools were controlled. Results showed a significant increase in teacher-perceived EFs from third to fourth grades and from fifth to sixth grades. This development was influenced both by the sex of the child and by the LPE. As perceived by teachers, the component self-control and self-monitoring was higher for girls than for boys, and planning abilities were higher for children from families with a higher LPE. Additional analyses showed that there is a systematic and statistically significant difference between the evaluations of the teachers and that of parents. Parents reported higher scores for planning, whereas teachers reported higher scores for self-control and self-monitoring. Evaluations by parents and teachers were different for girls, but not for boys. These findings are important because they imply that the development of EFs as perceived by parents and teachers is influenced by child-related factors. Second, there are clear differences in evaluations between teachers and parents. The AEFI appears to be a tool that is easily used by parents and teachers and shows potential for monitoring the development of EFs as perceived by significant others during young adolescence.
Hamaide, Julie; De Groof, Geert; Van Steenkiste, Gwendolyn; Jeurissen, Ben; Van Audekerke, Johan; Naeyaert, Maarten; Van Ruijssevelt, Lisbeth; Cornil, Charlotte; Sijbers, Jan; Verhoye, Marleen; Van der Linden, Annemie
2017-02-01
Zebra finches are an excellent model to study the process of vocal learning, a complex socially-learned tool of communication that forms the basis of spoken human language. So far, structural investigation of the zebra finch brain has been performed ex vivo using invasive methods such as histology. These methods are highly specific, however, they strongly interfere with performing whole-brain analyses and exclude longitudinal studies aimed at establishing causal correlations between neuroplastic events and specific behavioral performances. Therefore, the aim of the current study was to implement an in vivo Diffusion Tensor Imaging (DTI) protocol sensitive enough to detect structural sex differences in the adult zebra finch brain. Voxel-wise comparison of male and female DTI parameter maps shows clear differences in several components of the song control system (i.e. Area X surroundings, the high vocal center (HVC) and the lateral magnocellular nucleus of the anterior nidopallium (LMAN)), which corroborate previous findings and are in line with the clear behavioral difference as only males sing. Furthermore, to obtain additional insights into the 3-dimensional organization of the zebra finch brain and clarify findings obtained by the in vivo study, ex vivo DTI data of the male and female brain were acquired as well, using a recently established super-resolution reconstruction (SRR) imaging strategy. Interestingly, the SRR-DTI approach led to a marked reduction in acquisition time without interfering with the (spatial and angular) resolution and SNR which enabled to acquire a data set characterized by a 78μm isotropic resolution including 90 diffusion gradient directions within 44h of scanning time. Based on the reconstructed SRR-DTI maps, whole brain probabilistic Track Density Imaging (TDI) was performed for the purpose of super resolved track density imaging, further pushing the resolution up to 40μm isotropic. The DTI and TDI maps realized atlas-quality anatomical maps that enable a clear delineation of most components of the song control and auditory systems. In conclusion, this study paves the way for longitudinal in vivo and high-resolution ex vivo experiments aimed at disentangling neuroplastic events that characterize the critical period for vocal learning in zebra finch ontogeny. Copyright © 2016 Elsevier Inc. All rights reserved.
Sacral neuromodulation in the treatment of the unstable bladder.
Bosch, J L
1998-07-01
Sacral neuromodulation as a treatment for urge incontinence in patients with an unstable bladder is the subject of ongoing clinical studies. Although approximately 75% of the patients treated with a permanent sacral foramen electrode implant have experienced significant improvements, it is now also clear that there is an initial failure rate of about 25%. Recent studies have pointed out the importance of improved patient selection on the basis of sex differences, urodynamic parameters and psychological factors. Also, newer forms of test stimulation and permanent electrode implantation are being explored in an effort to improve on the present results.
[Sex differences and anesthesiology: preface and comments].
Nishno, Takashi
2009-01-01
In this special issue, the topic of sex difference in the field of anesthesiology is featured. Eight subtopics are discussed including 1) sex differences in cardiovascular medicine, 2) perioperative cardiovascular management, 3) sex differences in the respiratory functions of the upper airway, 4) sex differences in the anesthetic management, 5) sex differences in pain, 6) sex differences in laboratory medicine, 7) sex differences in pharmacokinetics of anesthetics, and 8) postoperative nausea and vomiting. Although recent clinical and experimental studies have shown the existence of sex and/or gender differences in many fields of medicine, our knowledge of sex differences in anesthesiology is apparently insufficient. I believe that anesthesiologists should pay more attention to this topic to improve our daily practice of anesthesia.
Toward a reconceptualization of "choice": challenges by women at the margins.
Luthra, R
1993-01-01
It has been suggested that recent first world and third world feminist movements have gained impetus from a shared emphasis on "body politics" (abortion, rape, and domestic violence). It has been made clear by other writers, however, that first and third world women (including women of color in the first world) have very different conceptions of which policies and practices should be pursued to change their reproduction experiences (because the overriding experiences of their entire lives are so very different). Likewise, the concept of "the right to choose" has been challenged on the grounds that it ignores the external conditions (such as economics) which, in fact, dictate "choice." Eugenics also influences which "choices" are promoted among populations considered "undesirable." The dilemmas associated with reproductive choices are further highlighted by debate about the use of amniocentesis in India for sex determination and female feticide. At the center of this debate is whether calling for a ban on this practice would support or violate a woman's choice. The rhetoric of choice arose in the first place because women who wanted to end a pregnancy had "no choice" but to seek illegal abortions. However, working class women and Black women in the US object to the narrowness in the abortion rights agenda dictated by the use of this term. To assert women's "choice" absolves all others of the responsibility for a pregnancy. The "choice" concept is also vulnerable to political manipulation. "Choice" also evades ethical problems such as sex selection. Disabled feminists have also pointed out that it is as important to create conditions which include "the choice to have a disabled child" as it is to choose not to be a mother. Can feminists oppose the selective abortion of female fetuses while leaving the choice to abort a defective or unwanted fetus of either sex up to the mother? Objection to sex determination can be categorized as consequentialist (based on various predicted social and psychological consequences, such as more men would lead to more violence in the world) or nonconsequentialist (based on the inherent immorality of selective abortion). The benefits of sex selection would possibly include a reduction in sex-linked diseases and a reduction in the overall birth rate. Most US feminists support the moral, but not the legal, condemnation of sex selection. In India, where sex selection is openly practiced, feminists have tried to achieve legal prohibition of the use of tests for this purpose. This difference from the US position may be due to the difference in the abortion context in the 2 countries. Whether feminists support legal and/or moral prohibition of sex selection, however, almost all call for the longterm structural changes which must be made in the context of imperialism, racism, and poverty which would allow true "choices" to prevail.
Is homophobia associated with an implicit same-sex attraction?
Macinnis, Cara C; Hodson, Gordon
2013-01-01
Some theorists propose that homophobia stems from underlying same-sex attraction. A few studies have tested this hypothesis, yet without a clear measure of implicit sexual attraction, producing mixed results. For the first time, we test this attraction-based account of homophobia among both men and women using an implicit measure of sexual attraction. No evidence of an attraction-based account of homophobia emerged. Instead, implicit same-sex attraction was related to positive evaluations of gay men and lesbians among female participants. Even in targeted analyses examining the relation between implicit same-sex attraction and homosexual evaluations among only those theoretically most likely to demonstrate an attraction-based homophobic effect, implicit same-sex attraction was not associated with evaluations of homosexuals or was associated with more positive evaluations of homosexuals. In addition, explicit same-sex attraction was related to positive evaluations of gay men and lesbians for male participants. These results are more in keeping with the attitude-similarity effect (i.e., people like, rather than dislike, similar others).
Bakker, Theo C M; Giger, Thomas; Frommen, Joachim G; Largiadèr, Carlo R
2017-08-01
There is a need for rapid and reliable molecular sexing of three-spined sticklebacks, Gasterosteus aculeatus, the supermodel species for evolutionary biology. A DNA region at the 5' end of the sex-linked microsatellite Gac4202 was sequenced for the X chromosome of six females and the Y chromosome of five males from three populations. The Y chromosome contained two large insertions, which did not recombine with the phenotype of sex in a cross of 322 individuals. Genetic variation (SNPs and indels) within the insertions was smaller than on flanking DNA sequences. Three molecular PCR-based sex tests were developed, in which the first, the second or both insertions were covered. In five European populations (from DE, CH, NL, GB) of three-spined sticklebacks, tests with both insertions combined showed two clearly separated bands on agarose minigels in males and one band in females. The tests with the separate insertions gave similar results. Thus, the new molecular sexing method gave rapid and reliable results for sexing three-spined sticklebacks and is an improvement and/or alternative to existing methods.
Sex-Related Cochlear Impairment in Cigarette Smokers
Lisowska, Grażyna; Jochem, Jerzy; Gierlotka, Agata; Misiołek, Maciej; Ścierski, Wojciech
2017-01-01
Background A number of studies have documented the influence of cigarette smoking on hearing. However, the association between sex and hearing impairment in smokers as measured by otoacoustic emissions (OAEs) has not been clearly established. The aim of this study was to analyze sex-specific effects of smoking on hearing via conventional and ultra-high-frequency pure tone audiometry (PTA), and OAEs, specifically spontaneous OAEs, click-evoked OAEs, and distortion-product OAEs. Material/Methods The study included 84 healthy volunteers aged 25–45 years (mean 34), among them 46 women (25 non-smokers and 21 smokers) and 38 men (16 non-smokers and 22 smokers). The protocol of the study included otoscopic examination, tympanometry, low-, moderate-, and ultra-high-frequency PTA, evaluation of spontaneous click-evoked (CEAOEs) and distortion-product otoacoustic emissions (DPOAEs), assessment of the DP-grams for 2f1-f2 (f1 from 977 to5 164 Hz), and input/output function at L2 primary tone level of 40–70 dB SPL. Results Smokers and non-smokers did not differ significantly in terms of their hearing thresholds assessed with tone audiometry. Male smokers presented with significantly lower levels of CEAOEs and DPOAEs than both male non-smokers and female smokers. Conclusions Smoking does not modulate a hearing threshold determined with PTA at low, moderate, and ultra-high frequencies, but causes a significant decrease in OAE levels. This effect was observed only in males, which implies that they are more susceptible to smoking-induced hearing impairment. Sex-specific differences in otoacoustic emissions level may reflect influences of genetic, hormonal, behavioral, and/or environmental factors. PMID:28110343
Bagley, Bradford D; Chang, Shu-Ching; Ehresman, David J; Eveland, Alan; Zitzow, Jeremiah D; Parker, George A; Peters, Jeffrey M; Wallace, Kendall B; Butenhoff, John L
2017-12-01
Perfluorooctane sulfonate (PFOS) is an environmentally persistent chemical. Dietary 100 ppm PFOS fed to male mice and rats for 4 weeks caused hepatic steatosis through an unknown mechanism. Choline deficient diets can cause hepatic steatosis. A hepatic choline:PFOS ion complex was hypothesized to cause this effect in mice. This study tested whether dietary choline supplementation attenuates PFOS-induced hepatic steatosis in rats. Sprague Dawley rats (12/sex/group) were fed control, choline supplemented (CS), 100 ppm PFOS, or 100 ppm PFOS + CS diets for 3 weeks. Male rats fed both PFOS-containing diets had decreased serum cholesterol and triglycerides (TGs) on days 9, 16, and/or 23 and increased hepatic free fatty acids and TG (ie, steatosis). Female rats fed both PFOS diets had decreased serum cholesterol on days 9 and 16 and decreased hepatic free fatty acid and TG at termination (ie, no steatosis). Liver PFOS concentrations were similar for both sexes. Liver choline concentrations were increased in male rats fed PFOS (±CS), but the increase was lower in the PFOS + CS group. Female liver choline concentrations were not altered by any diet. These findings demonstrate a clear sex-related difference in PFOS-induced hepatic steatosis in the rat. Additional evaluated mechanisms (ie, nuclear receptor activation, mRNA upregulation, and choline kinase activity inhibition) did not appear to be involved in the hepatic steatosis. Dietary PFOS (100 ppm) induced hepatic steatosis in male, but not female, rats that was not attenuated by choline supplementation. The mechanism of lipid accumulation and the sex-related differences warrant further investigation. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Age-related differences in muscle fatigue vary by contraction type: a meta-analysis.
Avin, Keith G; Law, Laura A Frey
2011-08-01
During senescence, despite the loss of strength (force-generating capability) associated with sarcopenia, muscle endurance may improve for isometric contractions. The purpose of this study was to perform a systematic meta-analysis of young versus older adults, considering likely moderators (ie, contraction type, joint, sex, activity level, and task intensity). A 2-stage systematic review identified potential studies from PubMed, CINAHL, PEDro, EBSCOhost: ERIC, EBSCOhost: Sportdiscus, and The Cochrane Library. Studies reporting fatigue tasks (voluntary activation) performed at a relative intensity in both young (18-45 years of age) and old (≥ 55 years of age) adults who were healthy were considered. Sample size, mean and variance outcome data (ie, fatigue index or endurance time), joint, contraction type, task intensity (percentage of maximum), sex, and activity levels were extracted. Effect sizes were (1) computed for all data points; (2) subgrouped by contraction type, sex, joint or muscle group, intensity, or activity level; and (3) further subgrouped between contraction type and the remaining moderators. Out of 3,457 potential studies, 46 publications (with 78 distinct effect size data points) met all inclusion criteria. A lack of available data limited subgroup analyses (ie, sex, intensity, joint), as did a disproportionate spread of data (most intensities ≥ 50% of maximum voluntary contraction). Overall, older adults were able to sustain relative-intensity tasks significantly longer or with less force decay than younger adults (effect size=0.49). However, this age-related difference was present only for sustained and intermittent isometric contractions, whereas this age-related advantage was lost for dynamic tasks. When controlling for contraction type, the additional modifiers played minor roles. Identifying muscle endurance capabilities in the older adult may provide an avenue to improve functional capabilities, despite a clearly established decrement in peak torque.
Evidence of oligogenic sex determination in the apple snail Pomacea canaliculata.
Yusa, Yoichi; Kumagai, Natsumi
2018-06-01
A small number of genes may interact to determine sex, but few such examples have been demonstrated in animals, especially through comprehensive mating experiments. The highly invasive apple snail Pomacea canaliculata is gonochoristic and shows a large variation in brood sex ratio, and the involvement of multiple genes has been suggested for this phenomenon. We conducted mating experiments to determine whether their sex determination involves a few or many genes (i.e., oligogenic or polygenic sex determination, respectively). Full-sib females or males that were born from the same parents were mated to an adult of the opposite sex, and the brood sex ratios of the parents and their offspring were investigated. Analysis of a total of 4288 offspring showed that the sex ratios of offspring from the full-sib females were variable but clustered into only a few values. Similar patterns were observed for the full-sib males, although the effect was less clear because fewer offspring were used (n = 747). Notably, the offspring sex ratios of all full-sib females in some families were nearly 0.5 (proportion of males) with little variation. These results indicate that the number of genotypes of the full-sibs, and hence genes involved in sex determination, is small in this snail. Such oligogenic systems may be a major sex-determining system among animals, especially those with variable sex ratios.
NASA Astrophysics Data System (ADS)
Kirby, Miranda; Zhang, Wei; Laratta, Peter K.; Sin, Don D.; Lam, Stephen; Coxson, Harvey O.
2014-03-01
Although there are more women than men dying of chronic obstructive pulmonary disease (COPD) in the United States and elsewhere, we still do not have a clear understanding of the differences in the pathophysiology of airflow obstruction between the sexes. Optical coherence tomography (OCT) is an emerging imaging technology that has the capability of imaging small bronchioles with resolution approaching histology. Therefore, our objective was to compare OCT-derived airway wall measurements between males and females matched for lung size and in anatomically matched small airways. Subjects 50-80 yrs were enrolled in the British Columbia Lung Health Study and underwent OCT and spirometry. OCT was performed using a 1.5mm diameter probe/sheath in anatomically matched airways for males and females; the right lower lobe (RB8 or RB9) or left lower lobe (LB8 or LB9) during end-expiration. OCT airway wall area (Aaw) was obtained by manual segmentation. For males and females there was no significant difference in OCT Aaw (p=0.12). Spearman correlation coefficients indicated that the forced expiratory volume in 1 second (FEV1) and Aaw were significantly correlated for males (r=-0.78, p=0.004) but not for females (r=-0.20, p=0.49) matched for lung size. These novel OCT findings demonstrate that while there were no overall sex differences in airway wall thickness, the relationship between lung function and airway wall thickness was correlated only in men. Therefore, factors other than airway remodeling may be driving COPD pathogenesis in women and OCT may provide important information for investigating airway remodeling and its relationship with COPD progression.
Dimitrijević, Mirjana; Arsenović-Ranin, Nevena; Bufan, Biljana; Nacka-Aleksić, Mirjana; Macanović, Mirjana Lazarević; Milovanović, Petar; Đurić, Marija; Sopta, Jelena; Leposavić, Gordana
2018-05-21
Collagen-induced arthritis (CIA) is a frequently used animal model of rheumatoid arthritis, human autoimmune disease that exhibits clear sex bias in incidence and clinical course. Female Dark Agouti rats immunized for CIA showed also greater incidence and higher arthritic score than their male counterparts. The study investigated sex differences in mechanisms controlling the primary immune responses in draining lymph nodes (dLNs), as a factor contributing to this dimorphism. The higher frequencies of CD4 + CD25 + Foxp3- cells, presumably activated effector T (Teff) cells, and IL-17+, IFN-γ + and IL-17 + IFN-γ + T cells were found in female compared with male rat dLNs. However, the frequency of CD4 + CD25 + Foxp3+ T regulatory cells (Treg) did not differ between sexes. Thus, CD4+ Teff cells/Treg ratio, and IL-17+ T cells/Treg and IFN-γ + T cells/Treg ratios were higher in female than in male rats, and among them was found lower frequency of PD-1+ cells. This suggested less efficient control of (auto)immune Th1/Th17 cell responses in female rat dLNs. On the contrary, the frequency of IL-4+ T cells was lower in female than in male rat dLNs. Consistently, the ratio of serum levels of collagen-specific IgG2a (IFN-γ-dependent, with an important pathogenic role in CIA) and IgG1 (IL-4-dependent) was shifted towards IgG2a in female compared with male rats. As a whole, the study suggests that sexual dimorphism in the control of T cell activation/polarization could contribute to sex bias in the susceptibility to CIA. Moreover, the study advises the use of animals of both sexes in the preclinical testing of new drugs for rheumatoid arthritis. Copyright © 2018 Elsevier Inc. All rights reserved.
Methodologic and ethical ramifications of sex and gender differences in public health research.
Lawrence, Kitty; Rieder, Anita
2007-01-01
Experience and investigative studies have shown that inequalities still exist between the sexes as well as in how public health policies and strategies approach the needs of the sexes. Sufficient attention has not been given to gender in public health research. Gender-based differences and similarities need to be promoted, and more structured guidelines are needed to build gender into public health research models. The aim of this review was to investigate and discuss public health research and to answer several related questions on gender biases, ethics and methodologies, and the establishment of guidelines. Using the search terms public health research and gender , or ethics , gender , and public health, a literature search was conducted predominately with, but not limited to, the PubMed database. English- or German-language articles were identified that examined the current status of gender in public health research as well as any relevant ethical guidelines. A review of the current literature showed that much work has been undertaken to promote the inclusion of gender in health research. However, deficiencies in the extent of gender-oriented research have been found in a number of key areas, including ethics committees and public health research methodology. Women were found to be underrepresented in ethics committees, which lack clear guidance, particularly in the European Union, to ensure the inclusion of gender issues in public health research. Data are often not sex disaggregated, and information on gender and social circumstances are frequently lacking. Furthermore, some methodologies, such as those used in the field of occupational health, underestimate men's or women's burden of disease. Recommendations include establishing guidelines for researchers on how to incorporate gender in health research, ensuring that the composition of ethics committees is more representative of society, and recommending that data collection systems or bodies ensure that data are disaggregated by sex and include socioeconomic aspects.
Manchanda, Samiksha; Saikia, Bedangshu; Gupta, Neeraj; Chowdhary, Sona; Puliyel, Jacob M.
2011-01-01
Objective Sex-ratio at birth in families with previous girls is worse than those with a boy. Our aim was to prospectively study in a large maternal and child unit sex-ratio against previous birth sex and use of traditional medicines for sex selection. Main Outcome Measures Sex-ratio among mothers in families with a previous girl and in those with a previous boy, prevalence of indigenous medicine use and sex-ratio in those using medicines for sex selection. Results Overall there were 806 girls to 1000 boys. The sex-ratio was 720∶1000 if there was one previous girl and 178∶1000 if there were two previous girls. In second children of families with a previous boy 1017 girls were born per 1000 boys. Sex-ratio in those with one previous girl, who were taking traditional medicines for sex selection, was 928∶1000. Conclusion Evidence from the second children clearly shows the sex-ratio is being manipulated by human interventions. More mothers with previous girls tend to use traditional medicines for sex selection, in their subsequent pregnancies. Those taking such medication do not seem to be helped according to expectations. They seem to rely on this method and so are less likely use more definitive methods like sex selective abortions. This is the first such prospective investigation of sex ratio in second children looked at against the sex of previous children. More studies are needed to confirm the findings. PMID:21697990
Sañudo, C; Alfonso, M; San Julián, R; Thorkelsson, G; Valdimarsdottir, T; Zygoyiannis, D; Stamataris, C; Piasentier, E; Mills, C; Berge, P; Dransfield, E; Nute, G R; Enser, M; Fisher, A V
2007-04-01
This paper describes the responses of consumers in six European countries (Greece, Italy, Spain, France, Iceland and United Kingdom) tasting meat from twelve different local types of lambs produced in those same six countries. Animals represented 10 breeds and crossbreeds, three sexes, several diets composed of either milk, concentrates and various forages as main ingredients and different slaughter ages, from 1 and 12 months, and carcass weights, from 5.5 to 30.4kg. Tests were conducted by 36 volunteer families in each of the six countries involved in the study. Families were asked to roast the joints using their own cooking criteria, evaluating (from "dislike extremely" to "like extremely") flavour, tenderness, juiciness and overall liking. Also the cook was asked to rate the odour during cooking. Country and lamb type and their interaction were statistically significant for all the variables analysed. Results suggest a link between the assessments of a given lamb type and the consumers' culinary background, showing clear associations between country and lamb type preferences. It was possible to separate, independently of the country, different groups of families with similar preferences. Five family groups, which included 88 families (40.74%), had a clear Mediterranean origin and preferred types of lamb fed either milk or mainly concentrate diets. Seven family groups, which included 93 families (43.06%) with a clear northern origin, preferred types reared on grass or with grass included in the diet. The rest of the groups (four) that included 35 families (16.20%) had no clear composition (northern or Mediterranean), and they had a wider taste preference. It can clearly be seen that there are two categories of consumers of lamb in the analysed European market: those who prefer "milk or concentrate taste" and those who prefer "grass taste".
A Population-Based Study of Alcohol Use in Same-Sex and Different-Sex Unions
Reczek, Corinne; Liu, Hui; Spiker, Russell
2014-01-01
The present study advances research on union status and health by providing a first look at alcohol use differentials among different-sex and same-sex married and cohabiting individuals using nationally representative population-based data (National Health Interview Surveys 1997–2011, N = 181,581). The results showed that both same-sex and different-sex married groups reported lower alcohol use than both same-sex and different-sex cohabiting groups. The results further revealed that same-sex and different-sex married individuals reported similar levels of alcohol use, whereas same-sex and different-sex cohabiting individuals reported similar levels of alcohol use. Drawing on marital advantage and minority stress approaches, the findings suggest that it is cohabitation status—not same-sex status—that is associated with elevated alcohol rates. PMID:24860195
Trait aggressiveness does not predict social dominance of rats in the Visible Burrow System.
Buwalda, Bauke; Koolhaas, Jaap M; de Boer, Sietse F
2017-09-01
Hierarchical social status greatly influences health and well-being in mammals, including humans. The social rank of an individual is established during competitive encounters with conspecifics. Intuitively, therefore, social dominance and aggressiveness may seem intimately linked. Yet, whether an aggressive personality trait may predispose individuals to a particular rank in a social colony setting remains largely unclear. Here we tested the hypothesis that high trait aggressiveness in Wildtype Groningen (WTG) rats, as assessed in a classic resident-intruder offensive aggression paradigm predicts social dominance in a mixed-sex colony housing using the Visible Burrow System (VBS). We also hypothesized that hierarchical steepness, as reflected in the number and intensity of the social conflicts, positively correlates with the average level of trait aggressiveness of the male subjects in the VBS. Clear and stable hierarchical ranking was formed within a few days in VBS colonies as indicated and reflected by a rapid loss of body weight in subordinates which stabilized after 2-3days. Social conflicts, that occurred mainly during these first few days, also resulted in bite wounds in predominantly subordinate males. Data clearly showed that trait aggressiveness does not predict dominance status. The most aggressive male in a mixed sex group of conspecifics living in a closed VBS environment does not always become the dominant male. In addition, data did not convincingly indicate that in colonies with only highly aggressive males, agonistic interactions were more intense. Number of bite wounds and body weight loss did not positively correlate with trait-aggressiveness of subordinates. In this study, rats from this wild-derived rat strain behave differently from Long-Evans laboratory rats that have been studied up till now in many experiments using the VBS. Strain dependent differences in the capacity to display appropriate social behavior fitting an adaptive strategy to a high or low social ranking position probably play an important role in the level of perceived stress in mixed sex social colonies like the VBS. Copyright © 2017 Elsevier Inc. All rights reserved.
Spectral imaging analysis for silkworm gender classification
NASA Astrophysics Data System (ADS)
Sumriddetchkajorn, Sarun; Kamtongdee, Chakkrit; Sa-Ngiamsak, Chiranut
2013-05-01
We examine the effect of different wavelength spectra in the performance of our optical penetration-based silkworm pupa sex identification system. With available low-cost light emitting diodes (LEDs), each emitting different wavelength spectra at 468 nm, 565 nm, 639 nm, 940 nm, and broad white light, we find that the body of the silkworm pupa can block blue and near infrared light while allowing green and red light pass through. In particular, the red light can clearly highlight an important organ called "chitin gland" of the female, leading to high accuracy of silkworm gender identification. In our experiment with 120 silkworm pupae, measured high average 92.8% and lower average 87.5% accuracies in identifying silkworm gender are obtained under red and white light LEDs, respectively.
Estrogens, Neuroinflammation, and Neurodegeneration
Villa, Alessandro; Vegeto, Elisabetta; Poletti, Angelo
2016-01-01
Inflammatory activation of microglia is a hallmark of several disorders of the central nervous system. In addition to protecting the brain against inflammatory insults, microglia are neuroprotective and play a significant role in maintaining neuronal connectivity, but the prolongation of an inflammatory status may limit the beneficial functions of these immune cells. The finding that estrogen receptors are present in monocyte-derived cells and that estrogens prevent and control the inflammatory response raise the question of the role that this sex steroid plays in the manifestation and progression of pathologies that have a clear sex difference in prevalence, such as multiple sclerosis, Parkinson's disease, and Alzheimer's disease. The present review aims to provide a critical review of the current literature on the actions of estrogen in microglia and on the involvement of estrogen receptors in the manifestation of selected neurological disorders. This current understanding highlights a research area that should be expanded to identify appropriate replacement therapies to slow the progression of such diseases. PMID:27196727
Sex Differences and Sex Steroids in Lung Health and Disease
Townsend, Elizabeth A.; Miller, Virginia M.
2012-01-01
Sex differences in the biology of different organ systems and the influence of sex hormones in modulating health and disease are increasingly relevant in clinical and research areas. Although work has focused on sex differences and sex hormones in cardiovascular, musculoskeletal, and neuronal systems, there is now increasing clinical evidence for sex differences in incidence, morbidity, and mortality of lung diseases including allergic diseases (such as asthma), chronic obstructive pulmonary disease, pulmonary fibrosis, lung cancer, as well as pulmonary hypertension. Whether such differences are inherent and/or whether sex steroids play a role in modulating these differences is currently under investigation. The purpose of this review is to define sex differences in lung structure/function under normal and specific disease states, with exploration of whether and how sex hormone signaling mechanisms may explain these clinical observations. Focusing on adult age groups, the review addresses the following: 1) inherent sex differences in lung anatomy and physiology; 2) the importance of certain time points in life such as puberty, pregnancy, menopause, and aging; 3) expression and signaling of sex steroid receptors under normal vs. disease states; 4) potential interplay between different sex steroids; 5) the question of whether sex steroids are beneficial or detrimental to the lung; and 6) the potential use of sex steroid signaling as biomarkers and therapeutic avenues in lung diseases. The importance of focusing on sex differences and sex steroids in the lung lies in the increasing incidence of lung diseases in women and the need to address lung diseases across the life span. PMID:22240244
Ghosh, Sudipta; Dosaev, Tasbulat; Prakash, Jai; Livshits, Gregory
2017-04-01
The major aim of this study was to conduct comparative quantitative-genetic analysis of the body composition (BCP) and somatotype (STP) variation, as well as their correlations with blood pressure (BP) in two ethnically, culturally and geographically different populations: Santhal, indigenous ethnic group from India and Chuvash, indigenous population from Russia. Correspondently two pedigree-based samples were collected from 1,262 Santhal and1,558 Chuvash individuals, respectively. At the first stage of the study, descriptive statistics and a series of univariate regression analyses were calculated. Finally, multiple and multivariate regression (MMR) analyses, with BP measurements as dependent variables and age, sex, BCP and STP as independent variables were carried out in each sample separately. The significant and independent covariates of BP were identified and used for re-examination in pedigree-based variance decomposition analysis. Despite clear and significant differences between the populations in BCP/STP, both Santhal and Chuvash were found to be predominantly mesomorphic irrespective of their sex. According to MMR analyses variation of BP significantly depended on age and mesomorphic component in both samples, and in addition on sex, ectomorphy and fat mass index in Santhal and on fat free mass index in Chuvash samples, respectively. Additive genetic component contributes to a substantial proportion of blood pressure and body composition variance. Variance component analysis in addition to above mentioned results suggests that additive genetic factors influence BP and BCP/STP associations significantly. © 2017 Wiley Periodicals, Inc.
Same-Sex and Different-Sex Cohabiting Couple Relationship Stability.
Manning, Wendy D; Brown, Susan L; Stykes, J Bart
2016-08-01
Relationship stability is a key indicator of well-being, but most U.S.-based research has been limited to different-sex couples. The 2008 panel of the Survey of Income and Program Participation (SIPP) provides an untapped data resource to analyze relationship stability of same-sex cohabiting, different-sex cohabiting, and different-sex married couples (n = 5,701). The advantages of the SIPP data include the recent, nationally representative, and longitudinal data collection; a large sample of same-sex cohabitors; respondent and partner socioeconomic characteristics; and identification of a state-level indicator of a policy stating that marriage is between one man and one woman (i.e., DOMA). We tested competing hypotheses about the stability of same-sex versus different-sex cohabiting couples that were guided by incomplete institutionalization, minority stress, relationship investments, and couple homogamy perspectives (predicting that same-sex couples would be less stable) as well as economic resources (predicting that same-sex couples would be more stable). In fact, neither expectation was supported: results indicated that same-sex cohabiting couples typically experience levels of stability that are similar to those of different-sex cohabiting couples. We also found evidence of contextual effects: living in a state with a constitutional ban against same-sex marriage was significantly associated with higher levels of instability for same- and different-sex cohabiting couples. The level of stability in both same-sex and different-sex cohabiting couples is not on par with that of different-sex married couples. The findings contribute to a growing literature on health and well-being of same-sex couples and provide a broader understanding of family life.
Birth cohort and the specialization gap between same-sex and different-sex couples.
Giddings, Lisa; Nunley, John M; Schneebaum, Alyssa; Zietz, Joachim
2014-04-01
We examine differences in household specialization between same-sex and different-sex couples within and across three birth cohorts: Baby Boomers, Generation X, and Generation Y. Using three measures of household specialization, we find that same-sex couples are less likely than their different-sex counterparts to exhibit a high degree of specialization. However, the "specialization gap" between same-sex and different-sex couples narrows across birth cohorts. These findings are indicative of a cohort effect. Our results are largely robust to the inclusion of a control for the presence of children and for subsets of couples with and without children. We provide three potential explanations for why the specialization gap narrows across cohorts. First, different-sex couples from more recent birth cohorts may have become more like same-sex couples in terms of household specialization. Second, social and legal changes may have prompted a greater degree of specialization within same-sex couples relative to different-sex couples. Last, the advent of reproductive technologies, which made having children easier for same-sex couples from more recent birth cohorts, could result in more specialization in such couples relative to different-sex couples.
Pembrey, Marcus; Saffery, Richard; Bygren, Lars Olov
2014-01-01
Mammalian experiments provide clear evidence of male line transgenerational effects on health and development from paternal or ancestral early-life exposures such as diet or stress. The few human observational studies to date suggest (male line) transgenerational effects exist that cannot easily be attributed to cultural and/or genetic inheritance. Here we summarise relevant studies, drawing attention to exposure sensitive periods in early life and sex differences in transmission and offspring outcomes. Thus, variation, or changes, in the parental/ancestral environment may influence phenotypic variation for better or worse in the next generation(s), and so contribute to common, non-communicable disease risk including sex differences. We argue that life-course epidemiology should be reframed to include exposures from previous generations, keeping an open mind as to the mechanisms that transmit this information to offspring. Finally, we discuss animal experiments, including the role of epigenetic inheritance and non-coding RNAs, in terms of what lessons can be learnt for designing and interpreting human studies. This review was developed initially as a position paper by the multidisciplinary Network in Epigenetic Epidemiology to encourage transgenerational research in human cohorts. PMID:25062846
Solovenchuk, L L; Arshavskiĭ, V V
1988-05-01
Clearly definable polymorphism of hemisphere interrelations represented by three phenotypes was established by the method of EEG cross-correlation analysis. Each phenotype of the three, representing polymorphism, is characterized by marked specificity of perception and the processing of information, which determines certain integral physiological characteristics of individuals. Phenotype frequencies in aboriginal and new-come populations of the North-East of the USSR differ significantly. In comparison with the inhabitants, Moscow Russians of Magadan are significantly closer to aboriginal population, judging by their frequency distribution, and this may be due to the strategy specificity in adaptation of populations to environmental conditions. Significant difference in phenotype frequencies is shown in representatives of both sexes, this being more pronounced in the aboriginal population. The establishment of interhemispheric reaction type by approx. 10th year of individual's life is confirmed. Phenotype frequency correlations, depending on parental phenotype, were analyzed in children. The role of genetic and environmental factors in manifestation of the hemisphere relationship type is discussed. Rationality of the population analysis of hemisphere asymmetry types is grounded, according to the study of behavioural genetics and population adaptation.
Menstrual cycle and the temporal discrimination threshold.
Mc Govern, Eavan M; O'Connor, Emer; Beiser, Ines; Williams, Laura; Butler, John S; Quinlivan, Brendan; Narasimham, Shruti; Beck, Rebecca; Reilly, Richard B; O'Riordan, Sean; Hutchinson, Michael
2017-02-01
The temporal discrimination threshold (TDT) is a proposed pre-clinical biomarker (endophenotype) for adult onset isolated focal dystonia (AOIFD). Age- and sex-related effects on temporal discrimination demonstrate that women, before the age of 40 years, have faster temporal discrimination than men but their TDTs worsen with age at almost three times the rate of men. Thus after 40 years the TDT in women is progressively worse than in men. AOIFD is an increasingly female-predominant disorder after the age of 40; it is not clear whether this age-related sexually-dimorphic difference observed for both the TDT and sex ratio at disease onset in AOIFD is a hormonal or chromosomal effect. The aim of this study was to examine temporal discrimination at weekly intervals during two consecutive menstrual cycles in 14 healthy female volunteers to determine whether physiological hormonal changes affected temporal discrimination. We observed no significant differences in weekly temporal discrimination threshold values during the menstrual cycles and no significant correlation with the menstrual cycle stage. This observed stability of temporal discrimination during cyclical hormonal change raises interesting questions concerning the age-related sexually-dimorphic decline observed in temporal discrimination. Our findings pave the way for future studies exploring potential pathomechanisms for this age-related deterioration.
Variable sexually dimorphic gene expression in laboratory strains of Drosophila melanogaster.
Baker, Dean A; Meadows, Lisa A; Wang, Jing; Dow, Julian At; Russell, Steven
2007-12-10
Wild-type laboratory strains of model organisms are typically kept in isolation for many years, with the action of genetic drift and selection on mutational variation causing lineages to diverge with time. Natural populations from which such strains are established, show that gender-specific interactions in particular drive many aspects of sequence level and transcriptional level variation. Here, our goal was to identify genes that display transcriptional variation between laboratory strains of Drosophila melanogaster, and to explore evidence of gender-biased interactions underlying that variability. Transcriptional variation among the laboratory genotypes studied occurs more frequently in males than in females. Qualitative differences are also apparent to suggest that genes within particular functional classes disproportionately display variation in gene expression. Our analysis indicates that genes with reproductive functions are most often divergent between genotypes in both sexes, however a large proportion of female variation can also be attributed to genes without expression in the ovaries. The present study clearly shows that transcriptional variation between common laboratory strains of Drosophila can differ dramatically due to sexual dimorphism. Much of this variation reflects sex-specific challenges associated with divergent physiological trade-offs, morphology and regulatory pathways operating within males and females.
Medically assisted reproduction and ethical challenges
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kaeaeriaeinen, Helena; Evers-Kiebooms, Gerry; Coviello, Domenico
2005-09-01
Many of the ethical challenges associated with medically assisted reproduction are societal. Should the technique be restricted to only ordinary couples or could it be used also to single females or couples of same sex? Should the future child be entitled to know the identity of the gamete donor? Should there be age limits? Can embryos or gametes be used after the death of the donor? Can surrogate mothers be part of the process? Can preimplantation diagnostics be used to select the future baby's sex? In addition, there are several clearly medical questions that lead to difficult ethical problems. Ismore » it safe to use very premature eggs or sperms? Is the risk for some rare syndromes caused by imprinting errors really increased when using these techniques? Do we transfer genetic infertility to the offspring? Is the risk for multiple pregnancies too high when several embryos are implanted? Does preimplantation diagnosis cause some extra risks for the future child? Should the counselling of these couples include information of all these potential but unlikely risks? The legislation and practices differ in different countries and ethical discussion and professional guidelines are still needed.« less
NASA Astrophysics Data System (ADS)
Hou, Ya-Yi; Han, Xiao-Dong; Suzuki, Yuzuru
2001-09-01
The profiles of cortisol, testosterone, 11-ketotestosterone and 17α, 20β-dihydroxy-4-pregnene-3-one in male rainbow trout reared under constant water temperature and natural photoperiod were determined by radioimmunoassay. Gonads of male rainbow trout reached maturity when the fish were two years old. Changes in the plasma levels of both sex steroid hormones and cortisol were closely related to the GSI. Plasma levels of testosterone, 11-ketotestosterone and 17α; 20β-dihydroxy 4-pregnene-3-one showed a clear peak in the annual breeding season, when the GSI reached their maxima. Plasma cortisol levels also showed clearly seasonal changes in both two- and three-year-old fish. The results suggest that the elevated plasma levels of cortisol may not just be due to stresses during the breeding season but have certain physiological functions in the reproduction of rainbow trout.
Physiological Comparison of Concentric and Eccentric Arm Cycling in Males and Females
Beaven, C. Martyn; Willis, Sarah J.; Cook, Christian J.; Holmberg, Hans-Christer
2014-01-01
Lower body eccentric exercise is well known to elicit high levels of muscular force with relatively low cardiovascular and metabolic strain. As a result, eccentric exercise has been successfully utilised as an adaptive stressor to improve lower body muscle function in populations ranging from the frail and debilitated, to highly-trained individuals. Here we investigate the metabolic, cardiorespiratory, and energy costs of upper body eccentric exercise in a healthy population. Seven men and seven women performed 4-min efforts of eccentric (ECC) or concentric (CON) arm cycling on a novel arm ergometer at workloads corresponding to 40, 60, and 80% of their peak workload as assessed in an incremental concentric trial. The heart rate, ventilation, cardiac output, respiratory exchange ratio, and blood lactate concentrations were all clearly greater in CON condition at all of the relative workloads (all p<0.003). Effect size calculations demonstrated that the magnitude of the differences in VO2 and work economy between the ECC and CON exercise ranged from very large to extremely large; however, in no case did mechanical efficiency (ηMECH) differ between the conditions (all p>0.05). In contrast, delta efficiency (ηΔ), as previously defined by Coyle and colleagues in 1992, demonstrated a sex difference (men>women; p<0.05). Sex differences were also apparent in arteriovenous oxygen difference and heart rate during CON. Here, we reinforce the high-force, low cost attributes of eccentric exercise which can be generalised to the muscles of the upper body. Upper body eccentric exercise is likely to form a useful adjunct in debilitative, rehabilitative, and adaptive clinical exercise programs; however, reports of a shift towards an oxidative phenotype should be taken into consideration by power athletes. We suggest delta efficiency as a sensitive measure of efficiency that allowed the identification of sex differences. PMID:25372404
Huddy, Timothy F.; Ogawa-Okada, Maya; Adkins, Jamie L.
2018-01-01
Recent studies in mice have demonstrated a sexual dimorphism in circadian entrainment to scheduled feeding. On a time restricted diet, males tend to develop food anticipatory activity (FAA) sooner than females and with a higher amplitude of activity. The underlying cause of this sex difference remains unknown. One study suggests that sex hormones, both androgens and estrogens, modulate food anticipatory activity in mice. Here we present results suggesting that the sex difference in FAA is unrelated to gonadal sex hormones. While a sex difference between males and females in FAA on a timed, calorie restricted diet was observed there were no differences between intact and gonadectomized mice in the onset or magnitude of FAA. To test other sources of the sex difference in circadian entrainment to scheduled feeding, we used sex chromosome copy number mutants, but there was no difference in FAA when comparing XX, XY-, XY-;Sry Tg, and XX;Sry Tg mice, demonstrating that gene dosage of sex chromosomes does not mediate the sex difference in FAA. Next, we masculinized female mice by treating them with 17-beta estradiol during the neonatal period; yet again, we saw no difference in FAA between control and masculinized females. Finally, we observed that there was no longer a sex difference in FAA for older mice, suggesting that the sex difference in FAA is age-dependent. Thus, our study demonstrates that singular manipulations of gonadal hormones, sex chromosomes, or developmental patterning are not able to explain the difference in FAA between young male and female mice. PMID:29385171
Aguayo, Antonio; Martin, Camille S; Huddy, Timothy F; Ogawa-Okada, Maya; Adkins, Jamie L; Steele, Andrew D
2018-01-01
Recent studies in mice have demonstrated a sexual dimorphism in circadian entrainment to scheduled feeding. On a time restricted diet, males tend to develop food anticipatory activity (FAA) sooner than females and with a higher amplitude of activity. The underlying cause of this sex difference remains unknown. One study suggests that sex hormones, both androgens and estrogens, modulate food anticipatory activity in mice. Here we present results suggesting that the sex difference in FAA is unrelated to gonadal sex hormones. While a sex difference between males and females in FAA on a timed, calorie restricted diet was observed there were no differences between intact and gonadectomized mice in the onset or magnitude of FAA. To test other sources of the sex difference in circadian entrainment to scheduled feeding, we used sex chromosome copy number mutants, but there was no difference in FAA when comparing XX, XY-, XY-;Sry Tg, and XX;Sry Tg mice, demonstrating that gene dosage of sex chromosomes does not mediate the sex difference in FAA. Next, we masculinized female mice by treating them with 17-beta estradiol during the neonatal period; yet again, we saw no difference in FAA between control and masculinized females. Finally, we observed that there was no longer a sex difference in FAA for older mice, suggesting that the sex difference in FAA is age-dependent. Thus, our study demonstrates that singular manipulations of gonadal hormones, sex chromosomes, or developmental patterning are not able to explain the difference in FAA between young male and female mice.
Same-Sex and Different-Sex Cohabiting Couple Relationship Stability
Manning, Wendy; Brown, Susan; Stykes, Bart
2016-01-01
Relationship stability is a key indicator of well-being, but most U.S.-based research has been limited to different-sex couples. The 2008 panel of the Survey of Income and Program Participation (SIPP) provides an untapped data resource to analyze relationship stability of same-sex cohabiting, different-sex cohabiting, and different-sex married couples (n = 5,701). The advantages of the SIPP data include the recent, nationally representative, and longitudinal data collection; a large sample of same-sex cohabitors; respondent and partner socioeconomic characteristics; and identification of a state-level indicator of a policy stating that marriage is between one man and one woman (i.e., DOMA). We tested competing hypotheses about the stability of same-sex versus different-sex cohabiting couples that were guided by incomplete institutionalization, minority stress, relationship investments, and couple homogamy perspectives (predicting that same-sex couples would be less stable) as well as economic resources (predicting that same-sex couples would be more stable). In fact, neither expectation was supported: results indicated that same-sex cohabiting couples typically experience levels of stability that are similar to those of different-sex cohabiting couples. We also found evidence of contextual effects: living in a state with a constitutional ban against same-sex marriage was significantly associated with higher levels of instability for same- and different-sex cohabiting couples. The level of stability in both same-sex and different-sex cohabiting couples is not on par with that of different-sex married couples. The findings contribute to a growing literature on health and well-being of same-sex couples and provide a broader understanding of family life. PMID:27383844
A reproductive threat-based model of evolved sex differences in jealousy.
Sagarin, Brad J; Becker, D Vaughn; Guadagno, Rosanna E; Wilkinson, Wayne W; Nicastle, Lionel D
2012-08-10
Although heterosexual women and men consistently demonstrate sex differences in jealousy, these differences disappear among lesbians and gay men as well as among heterosexual women and men contemplating same-sex infidelities (infidelities in which the partner and rival are the same sex). Synthesizing these past findings, the present paper offers a reproductive threat-based model of evolved sex differences in jealousy that predicts that the sexes will differ only when the jealous perceivers' reproductive outcomes are differentially at risk. This model is supported by data from a web-based study in which lesbians, gay men, bisexual women and men, and heterosexual women and men responded to a hypothetical infidelity scenario with the sex of the rival randomly determined. After reading the scenario, participants indicated which type of infidelity (sexual versus emotional) would cause greater distress. Consistent with predictions, heterosexual women and men showed a sex difference when contemplating opposite-sex infidelities but not when contemplating same-sex infidelities, whereas lesbians and gay men showed no sex difference regardless of whether the infidelity was opposite-sex or same-sex.
Biased dispersal of Metrioptera bicolor, a wing dimorphic bush-cricket.
Heidinger, Ina Monika Margret; Hein, Silke; Feldhaar, Heike; Poethke, Hans-Joachim
2018-04-01
In the highly fragmented landscape of central Europe, dispersal is of particular importance as it determines the long-term survival of animal populations. Dispersal not only secures the recolonization of patches where populations went extinct, it may also rescue small populations and thus prevent local extinction events. As dispersal involves different individual fitness costs, the decision to disperse should not be random but context-dependent and often will be biased toward a certain group of individuals (e.g., sex- and wing morph-biased dispersal). Although biased dispersal has far-reaching consequences for animal populations, immediate studies of sex- and wing morph-biased dispersal in orthopterans are very rare. Here, we used a combined approach of morphological and genetic analyses to investigate biased dispersal of Metrioptera bicolor, a wing dimorphic bush-cricket. Our results clearly show wing morph-biased dispersal for both sexes of M. bicolor. In addition, we found sex-biased dispersal for macropterous individuals, but not for micropters. Both, morphological and genetic data, favor macropterous males as dispersal unit of this bush-cricket species. To get an idea of the flight ability of M. bicolor, we compared our morphological data with that of Locusta migratoria and Schistocerca gregaria, which are very good flyers. Based on our morphological data, we suggest a good flight ability for macropters of M. bicolor, although flying individuals of this species are seldom observed. © 2016 Institute of Zoology, Chinese Academy of Sciences.
Perception of Sexual Orientation from Facial Structure: A Study with Artificial Face Models.
González-Álvarez, Julio
2017-07-01
Research has shown that lay people can perceive sexual orientation better than chance from face stimuli. However, the relation between facial structure and sexual orientation has been scarcely examined. Recently, an extensive morphometric study on a large sample of Canadian people (Skorska, Geniole, Vrysen, McCormick, & Bogaert, 2015) identified three (in men) and four (in women) facial features as unique multivariate predictors of sexual orientation in each sex group. The present study tested the perceptual validity of these facial traits with two experiments based on realistic artificial 3D face models created by manipulating the key parameters and presented to Spanish participants. Experiment 1 included 200 White and Black face models of both sexes. The results showed an overall accuracy (0.74) clearly above chance in a binary hetero/homosexual judgment task and significant differences depending on the race and sex of the face models. Experiment 2 produced five versions of 24 artificial faces of both sexes varying the key parameters in equal steps, and participants had to rate on a 1-7 scale how likely they thought that the depicted person had a homosexual sexual orientation. Rating scores displayed an almost perfect linear regression as a function of the parameter steps. In summary, both experiments demonstrated the perceptual validity of the seven multivariate predictors identified by Skorska et al. and open up new avenues for further research on this issue with artificial face models.
Sex workers, unite! (Litigating for sex workers' freedom of association in Russia).
Arps, F S E Freddie; Golichenko, Mikhail
2014-12-11
The existing legal framework in Russia makes sex work and related activities punishable offenses, leaving sex workers stigmatized, vulnerable to violence, and disproportionally affected by HIV and other sexually transmitted infections. In 2013, the Ministry of Justice, supported by the courts, refused registration and official recognition to the first all-Russia association of sex workers, referring to the fact that sex work is under administrative and criminal punitive bans and therefore the right of association for sex workers is unjustified. In light of international human rights standards, in particular the jurisprudence of the European Court of Human Rights, we examine in this paper whether the overall punitive legal ban on sex work in Russia is discriminatory. The government's positive obligations concerning discrimination against sex workers whose activities are consensual and between adults, and whose working conditions leave them among society's most vulnerable, should outweigh their punitive laws and policies around sex work. The scope of legal criminalization is narrow: it should apply only in exceptional cases where it is clearly justified. Copyright © 2014 Arps and Golichenko. This is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original author and source are credited.
Tong, Sok-Keng; Hsu, Hwei-Jan; Chung, Bon-chu
2010-08-15
The zebrafish is a popular model for genetic analysis and its sex differentiation has been the focus of attention for breeding purposes. Despite numerous efforts, very little is known about the mechanism of zebrafish sex determination. The lack of discernible sex chromosomes and the difficulty of distinguishing the sex of juvenile fish are two major obstacles that hamper the progress in such studies. To alleviate these problems, we have developed a scheme involving methyltestosterone treatment followed by natural mating to generate fish with predictable sex trait. Female F1 fish that gave rise to all-female offspring were generated. This predictable sex trait enables characterization of gonadal development in juvenile fish by histological examination and gene expression analysis. We found the first sign of zebrafish sex differentiation to be ovarian gonocyte proliferation and differentiation at 10 to 12 days post-fertilization (dpf). Somatic genes were expressed indifferently at 10 to 17 dpf, and then became sexually dimorphic at three weeks. This result indicates clear distinction of male and female gonads derived independently from primordial gonads. We classified the earliest stages of zebrafish sex determination into the initial preparation followed by female germ cell growth, oocyte differentiation, and somatic differentiation. Our genetic selection scheme matches the prediction that female-dominant genetic factors are required to determine zebrafish sex. Copyright 2010 Elsevier Inc. All rights reserved.
HIV behavioural risks and the role of work environment among Chinese male sex workers in Hong Kong.
Wong, William C W; Leung, Phil W S; Li, C W
2012-01-01
Male sex workers are a highly marginalised group in Hong Kong and it is increasingly so with an influx of them travelling from mainland China to work as "freelance" sex workers. This study aimed to measure important work environment variables that might affect the likelihood of condom use among male sex workers working in Hong Kong. A cross-sectional survey of 161 participants recruited by snowball and convenience sampling methods through outreach workers of a local non-governmental organization was conducted in 2007-2008. Only 27.4%, 54.7% and 42.6% reported consistent condom use when engaging in oral, anal and vaginal sex, respectively. Logistic regression shows unsafe sex was nearly four times (OR=3.41; 95%CI 1.51-7.69) as common in institutionalised male sex workers as among their independent counterparts. Lack of condoms provided at workplaces was a major barrier in this socio-legal context and was strongly associated with condom non-use amongst institutionalised sex workers (OR= 10.86; 95%CI 2.94-40.17). The present study finds that when compared with independent Male sex workers (MSWs), institutionalised MSWs were older, less educated, earned a higher income but more likely to engage in unsafe sex with their clients and their partners. Public health physicians must work with law-enforcing authorities to provide clear guidelines to remove these HIV prevention barriers.
A Systems Biology Approach to Investigating Sex Differences in Cardiac Hypertrophy.
Harrington, Josephine; Fillmore, Natasha; Gao, Shouguo; Yang, Yanqin; Zhang, Xue; Liu, Poching; Stoehr, Andrea; Chen, Ye; Springer, Danielle; Zhu, Jun; Wang, Xujing; Murphy, Elizabeth
2017-08-19
Heart failure preceded by hypertrophy is a leading cause of death, and sex differences in hypertrophy are well known, although the basis for these sex differences is poorly understood. This study used a systems biology approach to investigate mechanisms underlying sex differences in cardiac hypertrophy. Male and female mice were treated for 2 and 3 weeks with angiotensin II to induce hypertrophy. Sex differences in cardiac hypertrophy were apparent after 3 weeks of treatment. RNA sequencing was performed on hearts, and sex differences in mRNA expression at baseline and following hypertrophy were observed, as well as within-sex differences between baseline and hypertrophy. Sex differences in mRNA were substantial at baseline and reduced somewhat with hypertrophy, as the mRNA differences induced by hypertrophy tended to overwhelm the sex differences. We performed an integrative analysis to identify mRNA networks that were differentially regulated in the 2 sexes by hypertrophy and obtained a network centered on PPARα (peroxisome proliferator-activated receptor α). Mouse experiments further showed that acute inhibition of PPARα blocked sex differences in the development of hypertrophy. The data in this study suggest that PPARα is involved in the sex-dimorphic regulation of cardiac hypertrophy. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.
A Theoretical Analysis of Sex Differences In Same-Sex Friendships.
ERIC Educational Resources Information Center
Barth, Robert J.; Kinder, Bill N.
1988-01-01
Investigates sex differences in same-sex friendships of 312 undergraduate students in terms of the intersection and social penetration model of relationship development, and Bem's theory of sex role orientation. Finds significant sex-related differences in depth, duration, and involvement. (FMW)
Kirschbaum, Allison L; Peterson, Zoë D
2018-02-01
The term masturbation is often not clearly defined despite its prevalent use in sex education, sex research, and clinical settings. The purpose of this study was to understand what behaviors are typically considered to be masturbation as well as the situational and individual variables that may affect the labeling of a behavior as such. An online study of 564 individuals demonstrated that a wide variety of behaviors were considered to be masturbation by a majority of participants. No difference was found between men and women in the total number of behaviors labeled as masturbation. Both men and women were more likely to label a behavior as masturbation (1) if there was no sexual partner present than if there was and (2) if an orgasm occurred than if it did not. In addition, women were more likely than men to label a behavior as masturbation if they were alone and if no orgasm occurred. Younger age was associated with labeling more behaviors as masturbation, but sexual identity, self-pleasuring experience, partnered sexual experience, and attitudes toward masturbation were not related to the number of behaviors labeled as masturbation. Results speak to the importance of behavioral specificity when discussing masturbation with students, clients, and in sex research.
Horie, Yoshifumi; Yamagishi, Takahiro; Shintaku, Yoko; Iguchi, Taisen; Tatarazako, Norihisa
2018-07-01
Tributyltin, an organotin compound, was used worldwide as an antifouling agent in aquatic environments and there has been much concern about the toxicological and ecotoxicological properties of organotin compounds. Even though it has been prohibited worldwide, tributyltin is still detected at low concentrations in aquatic environments. Here we investigated the effects of tributyltin on the early life-stage, reproduction, and gonadal sex differentiation in Japanese medaka (Oryzias latipes). In adults, exposure to tributyltin at 3.82 μg/L suppressed fecundity and fertility and increased mortality. At 10.48 μg/L all medaka died by the sixth day of exposure. Exposure to tributyltin during early life-stages induced no significant differences in mortality or embryonic development, but growth was suppressed in groups exposed to 0.13 and 0.68 μg/L. Furthermore, there was no abnormal gonadal development in Japanese medaka exposed to tributyltin. These results provide evidence of the negative effects of tributyltin on reproduction in a teleost fish. Tributyltin did not affect gonadal sex differentiation in Japanese medaka, but fecundity and fertility were suppressed, although it is not clear whether this suppression resulted from the endocrine-disrupting action of tributyltin or its toxicity. Copyright © 2018 Elsevier Ltd. All rights reserved.
Nationwide survey on the organ-specific prevalence and its interaction with sarcoidosis in Japan.
Hattori, Takeshi; Konno, Satoshi; Shijubo, Noriharu; Yamaguchi, Tetsuo; Sugiyama, Yukihiko; Honma, Sakae; Inase, Naohiko; Ito, Yoichi M; Nishimura, Masaharu
2018-06-21
Previous studies attempted to characterize the subjects with sarcoidosis according to differences in sex, age, and the presence of specific organ involvement. However, significant interactions among these factors precluded a clear conclusion based on simple comparison. This study aimed to clarify the age- and sex-stratified prevalence of specific organ involvement and the heterogenous nature of sarcoidosis. Using the data of 9,965 patients who were newly registered into a database at the Ministry of Health, Labour and Welfare, Japan between 2002 and 2011, we evaluated the age- and sex-specific prevalence of the eye, lung, and skin involvement of sarcoidosis. We also attempted corresponding analysis considering multiple factors. As compared with several decades ago, the monophasic age distribution in men became biphasic, and the biphasic distribution in women, monophasic. The prevalence of pulmonary and cutaneous lesions was significantly associated with age, whereas the prevalence of ocular involvement showed a biphasic pattern. The prevalence of bilateral hilar lymphadenopathy was significantly higher, whereas the prevalence of diffuse lung shadow was significantly lower, in subjects with ocular involvement than those without ocular involvement. Corresponding analysis visually clarified the complex interactions among factors. Our results contribute to a better understanding of the heterogeneous features of sarcoidosis.
[Medical students' sexuality--beliefs and attitudes].
Müldner-Nieckowski, Łukasz; Sobański, Jerzy A; Klasa, Katarzyna; Dembińska, Edyta; Rutkowski, Krzysztof
2012-01-01
Ability and readiness to talk with patients about sexual problems not only depend on education in sexual physiology and pathology, but also on the doctors' beliefs and attitudes towards sexuality. Considering importance of these matters, the authors decided to collect and evaluate the data regarding attitudes and cognitive schemata of medical students. Analysis of selected convictions and attitudes towards sex life of IV-th grade students of medicine. There was self-report Questionnaire on Satisfaction with Sexual Life (KSS2) applied. Medical students filled-out the questionnaire when attending the courses of Psychopathology of neurotic disorders or Psychotherapy. Analysis of the collected data revealed differentiation of the studied group in regard of beliefs and attitudes towards sex life, dialogue about sex in erotic relationships, and seeking for professional help. Regarding some aspects, significant differences between women and men occurred. The following factors, which may negatively influence medical doctor's competencies in domain of sexual health, were identified: discomfort considering their own sexuality, avoidance of sexual drive, negative moral judgment of sexual activity. Assessment of influence of students' and doctors' own sexuality on their competencies in diagnostics and treatment requires further studies. There is a clear indication to look for the means for prophylaxis and correction of ineffective attitudes and convictions of future doctors', as professional sexual education or interpersonal trainings.
Arnold, Arthur P.; Chen, Xuqi; Itoh, Yuichiro
2014-01-01
Summary A modern general theory of sex determination and sexual differentiation identifies the factors that cause sexual bias in gene networks, leading to sex differences in physiology and disease. The primary sex-biasing factors are those encoded on the sex chromosomes that are inherently different in the male and female zygote. These factors, and downstream factors such as gonadal hormones, act directly on tissues to produce sex differences, and to antagonize each other to reduce sex differences. Recent study of mouse models such as the Four Core Genotypes has begun to distinguish between direct effects of sex chromosome complement (XX vs. XY) and hormonal effects. Several lines of evidence implicate epigenetic processes in the control of sex differences, although a great deal of more information is needed about sex differences in the epigenome. PMID:23027446
41 CFR 105-54.204 - Advisory committee membership.
Code of Federal Regulations, 2013 CFR
2013-07-01
... Administrator's signature to the GSA Committee Management Officer and to the Special Counsel for Ethics and... basis of race, color, age, national origin, religion, sex, or mental and physical handicap in selecting... cleared by the Designated Agency Ethics Official. ...
41 CFR 105-54.204 - Advisory committee membership.
Code of Federal Regulations, 2011 CFR
2011-01-01
... Administrator's signature to the GSA Committee Management Officer and to the Special Counsel for Ethics and... basis of race, color, age, national origin, religion, sex, or mental and physical handicap in selecting... cleared by the Designated Agency Ethics Official. ...
41 CFR 105-54.204 - Advisory committee membership.
Code of Federal Regulations, 2012 CFR
2012-01-01
... Administrator's signature to the GSA Committee Management Officer and to the Special Counsel for Ethics and... basis of race, color, age, national origin, religion, sex, or mental and physical handicap in selecting... cleared by the Designated Agency Ethics Official. ...
41 CFR 105-54.204 - Advisory committee membership.
Code of Federal Regulations, 2014 CFR
2014-01-01
... Administrator's signature to the GSA Committee Management Officer and to the Special Counsel for Ethics and... basis of race, color, age, national origin, religion, sex, or mental and physical handicap in selecting... cleared by the Designated Agency Ethics Official. ...
Sex Roles and Gender Differences in the Experience of Depression.
ERIC Educational Resources Information Center
Chevron, Eve S.; And Others
1978-01-01
Sex differences and sex role correlates of depressive experiences were studied in 87 female and 41 male college students. The sex differences and intrasex correlations found indicate that experiences of depression are associated with different facets of sex role stereotypes. (Author)
Sex differences in parent-infant interaction during free play, departure, and separation.
Weinraub, M; Frankel, J
1977-12-01
20 18-month-olds were observed with their mothers and 20 with their fathers in laboratory free-play, departure, and separation situations. Parent and infant behaviors were allowed to vary naturally. Although there were no parent sex or infant sex differences in infants' free-play behavior, there were parent sex X infant sex differences in parental free-play behaviors. Parents talked to, sat on the floor more with, and tended to share play more with same-sexed than opposite-sexed infants, and the patterning of free-play behaviors was different for mothers and fathers. During departure, fathers talked to the infants more than mothers. Infants were more distressed in the absence of same-sexed than opposite-sexed parents. There were infant sex X parent sex differences in the relationships between separation distress and parental free-play and departure behaviors. The implications of these findings for understanding differential roles of mothers and fathers, the development of sex differences, and the determinants of separation distress are discussed.
Sex differences in same-sex direct aggression and sociosexuality: the role of risky impulsivity.
Cross, Catharine P
2010-12-23
Sex differences in same-sex direct aggression and sociosexuality are among the most robust in the literature. The present article evaluated the hypothesis that both can be explained by a sex difference in the willingness to take impulsive risks. Self-report data were gathered from 3,775 respondents (1,514 female) on same-sex aggression, sociosexuality, and risky impulsivity. Risky impulsivity was higher for men than for women (d = .34) and path analysis showed it to be a common cause of same-sex aggression and sociosexuality for both sexes. However, it did not completely mediate the sex differences in same-sex aggression and sociosexuality. The results suggest that same-sex aggression and sociosexual behavior share a common psychological mechanism, but that fully explaining sex differences in aggression requires a more sensitive assay of impulsive risk and a consideration of dyadic processes.
A General Theory of Sexual Differentiation
Arnold, Arthur P.
2016-01-01
A general theory of mammalian sexual differentiation is proposed. All biological sex differences are the result of the inequality in effects of the sex chromosomes, which are the only factors that differ in XX vs. XY zygotes. This inequality leads to male-specific effects of the Y chromosome, including expression of the testis-determining gene Sry that causes differentiation of testes. Thus, Sry sets up lifelong sex differences in effects of gonadal hormones. Y genes also act outside of the gonads to cause male-specific effects. Differences in the number of X chromosomes between XX and XY cells causes sex differences in expression (1) of Xist, (2) of X genes that escape inactivation, and (2) of parentally imprinted X genes. Sex differences in phenotype are ultimately the result of multiple, independent sex-biasing factors, hormonal and sex chromosomal. These factors act in parallel and in combination to induce sex differences. They can also can offset each other to reduce sex differences. Other mechanisms, operating at the level of populations, cause groups of males to differ on average from groups of females. The theory has advantages for directing attention to inherent sex-biasing factors that operate in many tissues to cause sex differences, to cause sex-biased protection from disease, and to frame questions for further study. PMID:27870435
A general theory of sexual differentiation.
Arnold, Arthur P
2017-01-02
A general theory of mammalian sexual differentiation is proposed. All biological sex differences are the result of the inequality in effects of the sex chromosomes, which are the only factors that differ in XX vs. XY zygotes. This inequality leads to male-specific effects of the Y chromosome, including expression of the testis-determining gene Sry that causes differentiation of testes. Thus, Sry sets up lifelong sex differences in effects of gonadal hormones. Y genes also act outside of the gonads to cause male-specific effects. Differences in the number of X chromosomes between XX and XY cells cause sex differences in expression (1) of Xist, (2) of X genes that escape inactivation, and (3) of parentally imprinted X genes. Sex differences in phenotype are ultimately the result of multiple, independent sex-biasing factors, hormonal and sex chromosomal. These factors act in parallel and in combination to induce sex differences. They also can offset each other to reduce sex differences. Other mechanisms, operating at the level of populations, cause groups of males to differ on average from groups of females. The theory frames questions for further study, and directs attention to inherent sex-biasing factors that operate in many tissues to cause sex differences, and to cause sex-biased protection from disease. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Stoet, Gijsbert; Geary, David C.
2013-01-01
We analyzed one decade of data collected by the Programme for International Student Assessment (PISA), including the mathematics and reading performance of nearly 1.5 million 15 year olds in 75 countries. Across nations, boys scored higher than girls in mathematics, but lower than girls in reading. The sex difference in reading was three times as large as in mathematics. There was considerable variation in the extent of the sex differences between nations. There are countries without a sex difference in mathematics performance, and in some countries girls scored higher than boys. Boys scored lower in reading in all nations in all four PISA assessments (2000, 2003, 2006, 2009). Contrary to several previous studies, we found no evidence that the sex differences were related to nations’ gender equality indicators. Further, paradoxically, sex differences in mathematics were consistently and strongly inversely correlated with sex differences in reading: Countries with a smaller sex difference in mathematics had a larger sex difference in reading and vice versa. We demonstrate that this was not merely a between-nation, but also a within-nation effect. This effect is related to relative changes in these sex differences across the performance continuum: We did not find a sex difference in mathematics among the lowest performing students, but this is where the sex difference in reading was largest. In contrast, the sex difference in mathematics was largest among the higher performing students, and this is where the sex difference in reading was smallest. The implication is that if policy makers decide that changes in these sex differences are desired, different approaches will be needed to achieve this for reading and mathematics. Interventions that focus on high-achieving girls in mathematics and on low achieving boys in reading are likely to yield the strongest educational benefits. PMID:23516422
Stoet, Gijsbert; Geary, David C
2013-01-01
We analyzed one decade of data collected by the Programme for International Student Assessment (PISA), including the mathematics and reading performance of nearly 1.5 million 15 year olds in 75 countries. Across nations, boys scored higher than girls in mathematics, but lower than girls in reading. The sex difference in reading was three times as large as in mathematics. There was considerable variation in the extent of the sex differences between nations. There are countries without a sex difference in mathematics performance, and in some countries girls scored higher than boys. Boys scored lower in reading in all nations in all four PISA assessments (2000, 2003, 2006, 2009). Contrary to several previous studies, we found no evidence that the sex differences were related to nations' gender equality indicators. Further, paradoxically, sex differences in mathematics were consistently and strongly inversely correlated with sex differences in reading: Countries with a smaller sex difference in mathematics had a larger sex difference in reading and vice versa. We demonstrate that this was not merely a between-nation, but also a within-nation effect. This effect is related to relative changes in these sex differences across the performance continuum: We did not find a sex difference in mathematics among the lowest performing students, but this is where the sex difference in reading was largest. In contrast, the sex difference in mathematics was largest among the higher performing students, and this is where the sex difference in reading was smallest. The implication is that if policy makers decide that changes in these sex differences are desired, different approaches will be needed to achieve this for reading and mathematics. Interventions that focus on high-achieving girls in mathematics and on low achieving boys in reading are likely to yield the strongest educational benefits.
The Stability of Same-Sex Cohabitation, Different-Sex Cohabitation, and Marriage
ERIC Educational Resources Information Center
Lau, Charles Q.
2012-01-01
This study contributes to the emerging demographic literature on same-sex couples by comparing the level and correlates of union stability among 4 types of couples: (a) male same-sex cohabitation, (b) female same-sex cohabitation, (c) different-sex cohabitation, and (d) different-sex marriage. The author analyzed data from 2 British birth cohort…
Yunyong, Liu; Zhe, Wang; Junting, Xu; Yan, Zhou; Xiaoxia, An; Li, Zhao; Yuan, Gu; Chao, Jiang
2016-07-01
This study was designed to assess the levels of and associations between gay-related stressful events, social support, emotional distress and the number of unprotected anal intercourse partners among Chinese men who have sex with men. Using a respondent-driven sampling method, 807 men who have sex with men were recruited in urban areas of northeast China and data were collected via face-to-face interviews. Gay-related stressful events were measured using the Gay-Related Stressful Life Events Scale; levels of depression, anxiety symptoms and social support were measured using the Self-Rating Depression Scale, the Self-Rating Anxiety Scale and the Social Support Rating Scale, respectively. Over a quarter of study participants experienced gay-related stressful events during the preceding 3 months. Their average Self-Rating Depression Scale, Self-Rating Anxiety Scale and Social Support scores differed significantly from the national norm. Gay-related stressful events significantly correlated with anxiety (r = 0.167, p < 0.001), depression (r = 0.165, p < 0.001), social support (r = -0.107, p = 0.002) and number of unprotected anal intercourse partners (r = 0.13, p < 0.001), showing a clear dose-response relationship. Gay-related stressful events are common and are significantly associated with emotional distress, lack of social support and high-risk sexual behaviors among Chinese men who have sex with men. Multifaceted approaches are warranted to increase social support and reduce intolerance toward homosexual behaviors and to reduce risky sexual behaviors related to the rapid HIV epidemic among men who have sex with men population in China. © The Royal Australian and New Zealand College of Psychiatrists 2015.
Risk Adjustment and Primary Health Care in Chile
Vargas, Veronica; Wasem, Juergen
2006-01-01
Aim To offer a capitation formula with greater capacity for guiding resource spending on population with poorer health and lower socioeconomic status in the context of financing and equity in primary health care. Methods We collected two years of data on a sample of 10 000 individuals from a region in Chile, Valdivia and Temuco and evaluated three models to estimate utilization and expenditures per capita. The first model included age and sex; the second one included age, sex, and the presence of two key diagnoses; and the third model included age, sex, and the presence of seven key diagnoses. Regression results were evaluated by R2 and predictive ratios to select the best specifications. Results Per-capita expenditures by age and sex confirmed international trends, where children under five, women, and the elderly were the main users of primary health care services. Women sought health advice twice as much as men. Clear differences by socioeconomic status were observed for the indigent population aged ≥65 years who under-utilized primary health care services. From the three models, major improvement in the predictive power occurred from the demographic (adjusted R2, 9%) to the demographic plus two diagnoses model (adjusted R2, 27%). Improvements were modest when five other diagnoses were added (adjusted R2, 28%). Conclusion The current formula that uses municipality’s financial power and geographic location of health centers to adjust capitation payments provides little incentive to appropriate care for the indigent and people with chronic conditions. A capitation payment that adjusts for age, sex, and the presence of diabetes and hypertension will better guide resource allocation to those with poorer health and lower socioeconomic status. PMID:16758525
Gennatas, Efstathios D; Avants, Brian B; Wolf, Daniel H; Satterthwaite, Theodore D; Ruparel, Kosha; Ciric, Rastko; Hakonarson, Hakon; Gur, Raquel E; Gur, Ruben C
2017-05-17
Developmental structural neuroimaging studies in humans have long described decreases in gray matter volume (GMV) and cortical thickness (CT) during adolescence. Gray matter density (GMD), a measure often assumed to be highly related to volume, has not been systematically investigated in development. We used T1 imaging data collected on the Philadelphia Neurodevelopmental Cohort to study age-related effects and sex differences in four regional gray matter measures in 1189 youths ranging in age from 8 to 23 years. Custom T1 segmentation and a novel high-resolution gray matter parcellation were used to extract GMD, GMV, gray matter mass (GMM; defined as GMD × GMV), and CT from 1625 brain regions. Nonlinear models revealed that each modality exhibits unique age-related effects and sex differences. While GMV and CT generally decrease with age, GMD increases and shows the strongest age-related effects, while GMM shows a slight decline overall. Females have lower GMV but higher GMD than males throughout the brain. Our findings suggest that GMD is a prime phenotype for the assessment of brain development and likely cognition and that periadolescent gray matter loss may be less pronounced than previously thought. This work highlights the need for combined quantitative histological MRI studies. SIGNIFICANCE STATEMENT This study demonstrates that different MRI-derived gray matter measures show distinct age and sex effects and should not be considered equivalent but complementary. It is shown for the first time that gray matter density increases from childhood to young adulthood, in contrast with gray matter volume and cortical thickness, and that females, who are known to have lower gray matter volume than males, have higher density throughout the brain. A custom preprocessing pipeline and a novel high-resolution parcellation were created to analyze brain scans of 1189 youths collected as part of the Philadelphia Neurodevelopmental Cohort. A clear understanding of normal structural brain development is essential for the examination of brain-behavior relationships, the study of brain disease, and, ultimately, clinical applications of neuroimaging. Copyright © 2017 the authors 0270-6474/17/375065-09$15.00/0.
Weinraub, M; Clemens, L P; Sockloff, A; Ethridge, T; Gracely, E; Myers, B
1984-08-01
The onset and development of preschoolers' awareness of sex role stereotypes, gender labeling, gender identity, and sex-typed toy preference were explored in 26-, 31-, and 36-month-old children. Gender labeling, gender identity, sex-typed toy preferences, and awareness of adult sex role differences were observed in significantly more 26-month-old children than would have been expected by chance. Verbal gender labeling was observed in a majority of 26-month-olds, while verbal and nonverbal gender identity were observed in a majority of 31-month-olds. Nonverbal gender labeling and awareness of adult sex role differences were observed in a majority of children by 36 months. No evidence of awareness of sex differences in children's toys was found in the majority of children at any age. Awareness of sex role differences in children's toys was not related to awareness of adult sex role differences. Brighter children were more aware of adult sex role differences. Sex-typed toy preference was not related to awareness of sex role differences but was related to gender identity. Predictors of sex role development included the mothers' employment, and the father's personality traits, attitudes toward women, and sex-typed activities in the home. Implications for theories of early sex role development are discussed.
Daughter neglect, women's work, and marriage: Pakistan and Bangladesh compared.
Miller, B D
1984-01-01
This article looks at juvenile sex ratios, juvenile mortality, women's work roles and marriage patterns in Pakistan and bangladesh in order to assess whether patterns previously observed in India, namely, daughter neglect in the northwest and equal juvenile sex ratios in the eastern part of the country, are carried over into the 2 adjacent nations, Pakistan and Bangladesh, respectively. The Indian study indicates that nationwide sex ratio data, sample survey data on childhood mortality, longitudinal population records in several locations and ethonographic evidence all point to inequalities in mortality as the prime cause of unbalanced sex ratios. The juvenile sex ratios of Pakistan and Bangladesh are very different from 1 another. Whereas there are no regional contrasts among juvenile sex ratios within Bangladesh, it is greater within Pakistan. Sex ratio data correspond roughly to what the mortality data indicate in terms of the contrast between Pakistan and Bangladesh. The evidence on juvenile mortality in both countries is too scant to support an airtight argument that juvenile females in Pakistan have much higher mortality rates than boys, while mortality rates are more balanced in Bangladesh. But the existing evidence clearly points to that conclusion. The immediate causes of the greater sex-differential mortality in Pakistan cannot be documented in the available ethnographic literature. Biased allocation of food, medical care, and love might be operating. Looking at the economic and sociocultural complex that promotes much differences between Pakistan and Bangladesh, it is argued that, in both countries, class-based variations in both women's work and marriage patterns exist and are important. It is hypothesized that females in Pakistan are little valued for agricultural labor, and pose an economic liability on their families who need to provide a large dowry with her marriage to compensate for the daughter's low economic utility to the agrucultural workforce. Both agroeconomic and household economic factors would contribute to an intense preference for sons and a concomitant neglect of daughters. In Bangladesh, where female labor is highly valued, marriage costs for daughters would be relatively low. The present study reveals that, in spite of economic and cultural reasons for son preference in both Pakistan and Bangladesh, survival of daughters relative to sons is less impaired in the latter. The direction of change for both, however, appears toward increased devaluation of daughters, relative to sons, as tribal groups become settled peasants, as machines replace women's work functions, and as bridewealth is transformed into large cash dowries.
Pletzer, Belinda
2014-01-01
This article reviews the literature on sex-specific strategy use in cognitive tasks with the aim to carve out a link between sex differences in different cognitive tasks. I conclude that male strategies are commonly holistic and oriented toward global stimulus aspects, while female strategies are commonly decomposed and oriented toward local stimulus aspects. Thus, the strategies observed in different tasks, may depend on sex differences in attentional focus and hence sex differences in global-local processing. I hypothesize that strategy use may be sex hormone dependent and hence subject to change over the menstrual cycle as evidenced by findings in global-local processing and emotional memory. Furthermore, I propose sex hormonal modulation of hemispheric asymmetries as one possible neural substrate for this theory, thereby building on older theories, emphasizing the importance of sex differences in brain lateralization. The ideas described in the current article represent a perspective toward a unifying approach to the study of sex differences in cognition and their neural correlates.
Rich-Edwards, Janet W; Kaiser, Ursula B; Chen, Grace L; Manson, JoAnn E; Goldstein, Jill
2018-04-12
A sex and gender-informed perspective increases rigor, promotes discovery, and expands the relevance of biomedical research. In the current era of accountability to present data for males and females, thoughtful and deliberate methodology can improve study design and inference in sex and gender differences research. We address issues of motivation, subject selection, sample size, data collection, analysis, and interpretation, considering implications for basic, clinical, and population research. In particular, we focus on methods to test sex/gender differences as effect modification or interaction, and discuss why some inferences from sex-stratified data should be viewed with caution. Without careful methodology, the pursuit of sex difference research, despite a mandate from funding agencies, will result in a literature of contradiction. However, given the historic lack of attention to sex differences, the absence of evidence for sex differences is not necessarily evidence of the absence of sex differences. Thoughtfully conceived and conducted sex and gender differences research is needed to drive scientific and therapeutic discovery for all sexes and genders.
Basso, Agustín; Attademo, Andrés M; Lajmanovich, Rafael C; Peltzer, Paola M; Junges, Celina; Cabagna, Mariana C; Fiorenza, Gabriela S; Sanchez-Hernandez, Juan Carlos
2012-01-01
In this study, we determined normal serum butyrylcholinesterase (BChE) and carboxylesterase (CbE) activities in Tupinambis merianae in order to obtain reference values for organophosphorus pesticide monitoring. Forty-two T. merianae individuals were grouped by sex and size to identify potential differences in their enzyme levels to allow for proper representation of normal values for females, males, juveniles, and hatchlings. Mean CbE was determined using two model substrates: alpha-naphtylacetate (α-NA) and p-nitrophenyl valerate (4-NPV). BChE and CbE sensitivity to malaoxon (Mx) was also evaluated as well as the possibility of BChE reactivation with pyridine-2-aldoxime methochloride (2-PAM). Mean adult females' BChE was significantly higher than adult males, juveniles, and hatchlings. No significant differences were found between groups regarding CbE. CbE (4-NPV) activity showed slightly negative correlation with lizard snout-vent length, while BChE and CbE (α-NA) showed no correlation with body size. Apparent IC(50) values for BChE and CbE (α-NA) suggested different sensitivities among groups. CbE (4-NPV) could not be inhibited. All Mx-inhibited groups treated with 2-PAM in a final concentration of 2.8 mM showed clear signs of reactivation. In conclusion, the results demonstrate that (1) plasma esterase activity did not vary with age and sex, except for BChE activity, and (2) because biological and environmental variables could be confounding factors in the response of plasma cholinesterases, complementary biomarkers like CbE inhibition and oxime-induced reactivation of esterases are strongly recommended.
Lambdin, Barrot H.; Bruce, R. Douglas; Chang, Olivia; Nyandindi, Cassian; Sabuni, Norman; Zamudio-Haas, Sophia; McCurdy, Sheryl; Masao, Frank; Ivo, Yovin; Msami, Amani; Ubuguy, Omar; Mbwambo, Jessie
2013-01-01
Introduction Current estimates suggest an HIV prevalence of 42% among people who inject drugs (PWIDs) in Dar es Salaam, while HIV prevalence is estimated to be 8.8% among the general population in the city. To address the HIV epidemic in this population, the government of Tanzania began establishing HIV prevention, treatment and care services including outreach and medication assisted treatment (MAT) for PWIDs in 2010. We assessed gender inequities in utilization of outreach and MAT services and evaluated differences in HIV risk behaviors between female and male PWIDs. Materials and Methods Routine outreach data between December 2010 to mid-August 2012 and baseline data on clients enrolling in methadone from February 2011 to August 2012 were utilized. Binomial regression was used to estimate adjusted relative risk estimates comparing females to males. Results From December 2010 to August 2012, 8,578 contacts were made to drug users; among them 1,898 were injectors. A total of 453 injectors were eligible and referred to MAT, of which, 443 enrolled in treatment. However, regarding total outreach contacts, outreach to PWID, referral to MAT and enrollment in MAT, 8% or less of drug users accessing services were women. In contrast, weighted estimations from surveys suggest that 34% of PWIDs are female, and this approximation is similar to recent population size estimations. Overall, 43% of traditional outreach workers conducting outreach with drug users were female. Though reporting higher levels of condom usage, female PWID were more likely to report multiple sex partners, anal sex, commercial sex work and struggle under a higher burden of addiction, mental disorders and abuse. Conclusions Services have not been mobilized adequately to address the clear needs of females who inject drugs. A clear and urgent need exists for women-centered strategies that effectively engage female PWID into HIV prevention services. PMID:23825620
Iburg, T M; Arnbjerg, J; Rueløkke, M L
2013-02-01
Perineal glands in guinea pigs are part of the sebaceous glandular complex. Their secretions are used for scent marking. This is important for social status and can be seen in both sexes and castrated males. Discrepancy exits about the existence of these glands in female guinea pigs and knowledge of the anatomical consequences of castration on the male perineal glands is sparse. To examine these uncertainties related to gender, perineal glands from 13 sexually mature pet guinea pigs were examined macro- and microscopically. Clear gender differences in the anatomy of perineal glands were found, and castrated males showed signs of atrophy and fatty infiltration in the glands. Females do have perineal glands, although smaller than the glands in the male. The glands are typically sebaceous with multiple excretory ducts. A macroscopic unique feature in the males was the clearly evident orifices of a large excretory duct on each side of the slightly everted perineal sac. However, the reason for this gender difference is not clear. In castrated males, the orifices were atrophied and difficult to see. In addition, the sebaceous glands of the hair follicles in the skin folds of the perineal opening were smaller and less abundant in females and castrated males. The changes in castrated males are presumably linked to the hormonal changes and decreased secretion after castration. The dense keratin layer in the perineal sac was thicker in males than in both castrated males and females and could contribute to the concrement formation seen mainly in males. © 2012 Blackwell Verlag GmbH.
Does surgical genitoplasty affect gender identity in the intersex infant?
Nihoul-Fékété, C
2005-01-01
There is no clear-cut answer to the question of whether surgical genitoplasty affects gender identity in the intersex infant. The debate centres around which is more important for the development of gender identity: the biological sex of a child or the sex in which a child is reared. We believe that the surgical achievement of a phenotype concordant with the sex of rearing is a tremendous help to the parents of an intersex infant. We do not consider that the 'neutral' upbringing of a child with ambiguous genitalia is a feasible option, first because of the parents' distress which prevents them from raising their child normally and second because in most cultures around the world gender variants are not treated as equals. A neutral upbringing may induce psychosocial consequences that are more pernicious than carefully considered neonatal sex attribution and concordant surgical genitoplasty. (c) 2005 S. Karger AG, Basel.
NASA Astrophysics Data System (ADS)
Baker, Dale
This study examined the effects of single-sex middle school science and mathematics classrooms with high minority enrollment on achievement, affect, peer, and teacher-student interactions. All students earned higher grades in mathematics than in science. Girls earned higher grades than boys. The higher grades of girls were not clearly attributable to the singlesex environment, and aspects of the single-sex environment interfered with boys' achievement. The single-sex environment contributed to girls', but not boys', feelings of empowerment, peer support, and positive self-concept. The curriculum and pedagogy were better suited to girls than to boys, leading to discipline problems and hostile interactions. However, boys were more engaged in technology-based activities than girls. Overall, all-boy classes were less supportive learning environments than all-girl classes. Although the results replicate findings elsewhere, this is the only study to look at minority students in middle school.
Paul Sullins, D
2017-12-01
Because of classification errors reported by the National Center for Health Statistics, an estimated 42 % of the same-sex married partners in the sample for this study are misclassified different-sex married partners, thus calling into question findings regarding same-sex married parents. Including biological parentage as a control variable suppresses same-sex/different-sex differences, thus obscuring the data error. Parentage is not appropriate as a control because it correlates nearly perfectly (+.97, gamma) with the same-sex/different-sex distinction and is invariant for the category of joint biological parents.
Rovatsos, Michail; Pokorná, Martina Johnson; Altmanová, Marie; Kratochvíl, Lukáš
2015-01-01
Amniotes possess variability in sex determining mechanisms, however, this diversity is still only partially known throughout the clade and sex determining systems still remain unknown even in such a popular and distinctive lineage as chameleons (Squamata: Acrodonta: Chamaeleonidae). Here, we present evidence for female heterogamety in this group. The Malagasy giant chameleon (Furcifer oustaleti) (chromosome number 2n = 22) possesses heteromorphic Z and W sex chromosomes with heterochromatic W. The panther chameleon (Furcifer pardalis) (2n = 22 in males, 21 in females), the second most popular chameleon species in the world pet trade, exhibits a rather rare Z1Z1Z2Z2/Z1Z2W system of multiple sex chromosomes, which most likely evolved from W-autosome fusion. Notably, its neo-W chromosome is partially heterochromatic and its female-specific genetic content has expanded into the previously autosomal region. Showing clear evidence for genotypic sex determination in the panther chameleon, we resolve the long-standing question of whether or not environmental sex determination exists in this species. Together with recent findings in other reptile lineages, our work demonstrates that female heterogamety is widespread among amniotes, adding another important piece to the mosaic of knowledge on sex determination in amniotes needed to understand the evolution of this important trait. PMID:26286647
Brase, Gary L; Adair, Lora; Monk, Kale
2014-02-04
To the extent that sex differences are mediated by mechanisms such as sex-roles and beliefs, individual differences in these more proximate traits should account for significant portions of relevant sex differences. Differences between women and men in reactions to sexual and emotional infidelity were assessed in a large sample of participants (n = 477), and these target reactions were evaluated as a function of many potential proximate mediators (infidelity implications beliefs, gender-role beliefs, interpersonal trust, attachment style, sociosexuality, and culture of honor beliefs) and as a function of participant sex. Results found a consistent sex difference that was not mediated by any other variables, although a handful of other variables were related to male, but not female, individual differences. These findings suggest particularly promising directions for future research on integrating evolutionarily based sex differences and proximate individual differences.
Ajdacic-Gross, Vladeta; Rodgers, Stephanie; Müller, Mario; Hengartner, Michael P; Aleksandrowicz, Aleksandra; Kawohl, Wolfram; Heekeren, Karsten; Rössler, Wulf; Angst, Jules; Castelao, Enrique; Vandeleur, Caroline; Preisig, Martin
2016-09-01
Interest in subtypes of mental disorders is growing in parallel with continuing research progress in psychiatry. The aim of this study was to examine pure animal phobia in contrast to other specific phobias and a mixed subtype. Data from three representative Swiss community samples were analysed: PsyCoLaus (n = 3720), the ZInEP Epidemiology Survey (n = 1500) and the Zurich Study (n = 591). Pure animal phobia and mixed animal/other specific phobias consistently displayed a low age at onset of first symptoms (8-12 years) and clear preponderance of females (OR > 3). Meanwhile, other specific phobias started up to 10 years later and displayed almost a balanced sex ratio. Pure animal phobia showed no associations with any included risk factors and comorbid disorders, in contrast to numerous associations found in the mixed subtype and in other specific phobias. Across the whole range of epidemiological parameters examined in three different samples, pure animal phobia seems to represent a different entity compared to other specific phobias. The etiopathogenetic mechanisms and risk factors associated with pure animal phobias appear less clear than ever.
Sex Differences in Human and Animal Toxicology.
Gochfeld, Michael
2017-01-01
Sex, the states of being female or male, potentially interacts with all xenobiotic exposures, both inadvertent and deliberate, and influences their toxicokinetics (TK), toxicodynamics, and outcomes. Sex differences occur in behavior, exposure, anatomy, physiology, biochemistry, and genetics, accounting for female-male differences in responses to environmental chemicals, diet, and pharmaceuticals, including adverse drug reactions (ADRs). Often viewed as an annoying confounder, researchers have studied only one sex, adjusted for sex, or ignored it. Occupational epidemiology, the basis for understanding many toxic effects in humans, usually excluded women. Likewise, Food and Drug Administration rules excluded women of childbearing age from drug studies for many years. Aside from sex-specific organs, sex differences and sex × age interactions occur for a wide range of disease states as well as hormone-influenced conditions and drug distribution. Women have more ADRs than men; the classic sex hormone paradigm (gonadectomy and replacement) reveals significant interaction of sex and TK including absorption, distribution, metabolisms, and elimination. Studies should be designed to detect sex differences, describe the mechanisms, and interpret these in a broad social, clinical, and evolutionary context with phenomena that do not differ. Sex matters, but how much of a difference is needed to matter remains challenging.
Sex Differences in Human and Animal Toxicology: Toxicokinetics
Gochfeld, Michael
2016-01-01
Sex, the states of being female or male, potentially interacts with all xenobiotic exposures, both inadvertent and deliberate, and influences their toxicokinetics, toxicodynamics, and outcomes. Sex differences occur in behavior, exposure, anatomy, physiology, biochemistry, and genetics, accounting for female-male differences in responses to environmental chemicals, diet, and pharmaceuticals, including adverse drug reactions. Often viewed as an annoying confounder, researchers have studied only one sex, adjusted for sex, or ignored it. Occupational epidemiology, the basis for understanding many toxic effects in humans, usually excluded women. Likewise FDA rules excluded women of child-bearing age from drug studies for many years. Aside from sex-specific organs, sex differences and sex × age interactions occur for a wide range of disease states as well as hormone-influenced conditions and drug distribution. Women have more adverse drug reactions than men, The Classic Sex Hormone Paradigm (gonadectomy and replacement) reveals significant interaction of sex and toxicokinetics including absorption, distribution, metabolisms and elimination. Studies should be designed to detect sex differences, describe the mechanisms, and interpret these in a broad social, clinical and evolutionary context with phenomena that do not differ. Sex matters, but how much of a difference is needed to matter remains challenging. PMID:27895264
A systematic literature review of sex differences in childhood language and brain development.
Etchell, Andrew; Adhikari, Aditi; Weinberg, Lauren S; Choo, Ai Leen; Garnett, Emily O; Chow, Ho Ming; Chang, Soo-Eun
2018-06-01
The extent of sex differences in childhood language development is unclear. We conducted a systematic literature review synthesizing results from studies examining sex differences in brain structure and function relevant to language development during childhood. We searched PubMed and Scopus databases, and this returned a total of 46 published studies meeting criteria for inclusion that directly examined sex differences in brain development relevant to language function in children. The results indicate that: (a) sex differences in brain structure or function do not necessarily lead to differences in language task performance; (b) evidence for sex differences in brain and language development are limited; (c) when present, sex differences often interact with a variety of factors such as age and task. Overall, the magnitude of sexual dimorphism of brain developmental trajectories associated with language is not as significant as previously thought. Sex differences were found, however, in studies employing tighter age ranges. This suggests that sex differences may be more prominent during certain developmental stages but are negligible in other stages, likely due to different rates of maturation between the sexes. More research is needed to improve our understanding of how sex differences may arise due to the influence of sex hormones and developmental stages, and how these differences may lead to differences in various language task performance. These studies are expected to provide normative information that may be used in studies examining neurodevelopmental disorders that frequently affect more males than females, and also often affect language development. Copyright © 2018 Elsevier Ltd. All rights reserved.
Long-Term Fragility of Y Chromosomes Is Dominated by Short-Term Resolution of Sexual Antagonism
Blackmon, Heath; Brandvain, Yaniv
2017-01-01
The evolution of heteromorphic sex chromosomes has fascinated biologists, inspiring theoretical models, experimental studies, and studies of genome structure. This work has produced a clear model, in which heteromorphic sex chromosomes result from repeated fixations of inversions (or other recombination suppression mechanisms) that tether sexually antagonistic alleles to sex-determining regions, followed by the degeneration of these regions induced by the lack of sex chromosome recombination in the heterogametic sex. However, current models do not predict if inversions are expected to preferentially accumulate on one sex-chromosome or another, and do not address if inversions can accumulate even when they cause difficulties in pairing between heteromorphic chromosomes in the heterogametic sex increasing aneuploidy or meiotic arrest. To address these questions, we developed a population genetic model in which the sex chromosome aneuploidy rate is elevated when males carry an inversion on either the X or Y chromosome. We show that inversions fix more easily when male-beneficial alleles are dominant, and that inversions on the Y chromosome fix with lower selection coefficients than comparable X chromosome inversions. We further show that sex-chromosome inversions can often invade and fix despite causing a substantial increase in the risk of aneuploidy. As sexual antagonism can lead to the fixation of inversions that increase sex chromosomes aneuploidy (which underlies genetic diseases including Klinefelter and Turner syndrome in humans) selection could subsequently favor diverse mechanisms to reduce aneuploidy—including alternative meiotic mechanisms, translocations to, and fusions with, the sex chromosomes, and sex chromosome turnover. PMID:29021279
Fedak, Mike; Årthun, Marius; Nicholls, Keith; Robinson, Patrick; Costa, Dan; Biuw, Martin
2016-01-01
Hauling out is an essential component of pinniped life-history. Haul-out behaviour may be affected by biological (e.g. sex, age and condition) and physical factors (e.g. food availability and environmental conditions), and identifying these factors may help explain the spatio-temporal distribution and habitat use of pinnipeds. The aim of this study is to describe observed winter haul-out patterns of adult Weddell seals in the Weddell Sea and investigate the role of potential predictors to gain insight into the way these animals interact with the physical environment in this region. We examined the haul-out behaviour in relation to available biological (i.e., diving effort, sex) and physical information (i.e., sun angle). Thirty-three satellite telemetry tags were deployed on adult Weddell seals in the southern Weddell Sea during February 2007, 2009 and 2011, following their annual moult recording information on the behavioural mode of the animal: at surface, hauled out or diving. At the end of the austral summer Weddell seals spent, on average, more than 40% of their time hauled out on the ice. Under constant light conditions, it appears that physiological factors drive sex differences in the timing and duration of haul-out behaviour, with females spending on average more time hauled out than males during daylight hours. This time spent hauled-out declined to around 15% in both sexes by the beginning of autumn and remained at this level with a clear nocturnal haul-out pattern during the winter. The time spent diving increased during this period, indicating an increase in foraging effort during the winter months, and led to a common haul-out pattern in both sexes over winter. We found a positive relationship between haul-out duration and the percentage of time spent diving prior to a haul-out in both sexes, with the exception of female daytime haul-outs early in the year. PMID:27196097
Krause, James S; Ricks, Jillian M
2012-04-01
To identify the stability of vocational interests first assessed during inpatient rehabilitation for spinal cord injury and again an average of 834.9 days postinjury to determine the extent to which stability of interest varies as a function of race and sex. Longitudinal. Data were collected at a specialty hospital. At enrollment, participants were a minimum of 16 years of age, were currently hospitalized for inpatient rehabilitation, were less than 6 months postinjury, had residual impairment after traumatic spinal cord injury, and were either white or black, and non-Hispanic. Participants (N=304) were assessed an average ± SD of 50±26.6 days after injury and again an average ± SD of 834.9±192.7 days postinjury (averaged 785.1 d between assessments). Not applicable. The Strong Interest Inventory, a 317-item vocational interests measure. A repeated-measures general linear model was used with 4 groups based on a combination of race and sex. Significant cohort by time interactions were observed on 4 general occupational themes (investigative, artistic, enterprising, and conventional). In nearly all cases, black women showed decreases in average interest scores compared with the other groups. There was a clear pattern of change in the direction of greater homogeneity of interests over time as measured by the range of theme scores between cohorts based on sex and race. Although changes in mean interest profiles varied as a function of sex and race, less consistent differences were observed when stability coefficients were the measure of change. The direction and degree of change in mean scores for vocational interests was related to sex and race. With the exception of black women, vocational interests increased from baseline to follow-up. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Boehme, Lars; Baker, Amy; Fedak, Mike; Årthun, Marius; Nicholls, Keith; Robinson, Patrick; Costa, Dan; Biuw, Martin; Photopoulou, Theoni
2016-01-01
Hauling out is an essential component of pinniped life-history. Haul-out behaviour may be affected by biological (e.g. sex, age and condition) and physical factors (e.g. food availability and environmental conditions), and identifying these factors may help explain the spatio-temporal distribution and habitat use of pinnipeds. The aim of this study is to describe observed winter haul-out patterns of adult Weddell seals in the Weddell Sea and investigate the role of potential predictors to gain insight into the way these animals interact with the physical environment in this region. We examined the haul-out behaviour in relation to available biological (i.e., diving effort, sex) and physical information (i.e., sun angle). Thirty-three satellite telemetry tags were deployed on adult Weddell seals in the southern Weddell Sea during February 2007, 2009 and 2011, following their annual moult recording information on the behavioural mode of the animal: at surface, hauled out or diving. At the end of the austral summer Weddell seals spent, on average, more than 40% of their time hauled out on the ice. Under constant light conditions, it appears that physiological factors drive sex differences in the timing and duration of haul-out behaviour, with females spending on average more time hauled out than males during daylight hours. This time spent hauled-out declined to around 15% in both sexes by the beginning of autumn and remained at this level with a clear nocturnal haul-out pattern during the winter. The time spent diving increased during this period, indicating an increase in foraging effort during the winter months, and led to a common haul-out pattern in both sexes over winter. We found a positive relationship between haul-out duration and the percentage of time spent diving prior to a haul-out in both sexes, with the exception of female daytime haul-outs early in the year.
The relationship of modernity of sex roles to pregnancy planning.
Jurich, J
1984-08-01
This study investigates the relationship of women's role modernity to pregnancy planning. The subjects were 59 married primiparous women aged 18 to 33 who had given birth in a metropolitan midwestern hospital. Over 1/2 the sample had some college eduction. The pregnancy planning variable is operationalized as the implementation of family planning goals. Subjects who desired pregnancy and actively attempted to conceive are considered to be planners. In contrast, nonplanners are defined as women who preferred to avoid pregnancy but were not successful and women who did not actively seek or avoid pregancy. The modernity of sex roles variable is operationalized through use of the Scanzoni instrument. This instrument is constructed from a series of items that measure 3 social positions related to sex roles in the family context: those of wife, husband and mother. The instrument is modified in this investigation, leaving 21 5-point scale items to be included in the data analysis. Smallest space analysis of the inter-item correlation matrix demonstrate that the social positions of wife and husband do not clearly reflect different aspects of sex role modernity. A comparison of the average inter-item correlation for the variables within each social position with the average inter-item for the variables across the positions reveals that the dimensions proposed by Scanzoni are not empirically different. In light of these findings, further exploratory data analysis of all items was conducted to discern which items do empirically cluster together. Scanzoni's 21 sex role items were submitted to principal component factor analysis; 3 factors emerged. 1) wife-husband equlity; 2) flexibility in role integration; and 3) values regarding primary role. 3 new sex role modernity values were created to correspond to the 3 factors and were then used to explore the relationship between sex role modernity and pregnancy planning. Chi square analyses were not statistically significant. Therefore, the hypothesis that women at the extremes of the modernity continuum would be more likely to plan than women who fall in the middle, was rejected. Although no relationship between the sex role factors and pregnancy planning was found, 6 of the Scanzoni items, when linearly combined, manifested a strong relationship to planning: 1) wife's emotional nature; 2) wife's most important task is caring for husbands and kids; 3) wife takes job if not satisfied with wife/mom role; 4) wife gives up job if inconveniences husband/kids; 5) wife's job as important as husband's job; 6) women's pay equal to man's. Although 4 of these items load on the sex role factors, it is unclear whether they are truly reflective of these factors.
Arnold, Arthur P; Cassis, Lisa A; Eghbali, Mansoureh; Reue, Karen; Sandberg, Kathryn
2017-05-01
This review summarizes recent evidence concerning hormonal and sex chromosome effects in obesity, atherosclerosis, aneurysms, ischemia/reperfusion injury, and hypertension. Cardiovascular diseases occur and progress differently in the 2 sexes, because biological factors differing between the sexes have sex-specific protective and harmful effects. By comparing the 2 sexes directly, and breaking down sex into its component parts, one can discover sex-biasing protective mechanisms that might be targeted in the clinic. Gonadal hormones, especially estrogens and androgens, have long been found to account for some sex differences in cardiovascular diseases, and molecular mechanisms mediating these effects have recently been elucidated. More recently, the inherent sexual inequalities in effects of sex chromosome genes have also been implicated as contributors in animal models of cardiovascular diseases, especially a deleterious effect of the second X chromosome found in females but not in males. Hormonal and sex chromosome mechanisms interact in the sex-specific control of certain diseases, sometimes by opposing the action of the other. © 2017 American Heart Association, Inc.
Baumle, Amanda K
2014-01-01
In this article, I use pooled data from the 2008-2010 American Community Surveys to examine outcomes for different-sex married, different-sex cohabiting, and same-sex cohabiting elders across several key economic and health indicators, as well as other demographic characteristics. The findings suggest that elders in same-sex cohabiting partnerships differ from those in different-sex marriages and different-sex cohabiting relationships in terms of both financial and health outcomes, and that women in same-sex cohabiting partnerships fare worse than men or women in other couple types. The results indicate that financial implications related to the sex of one's partner might be more predictive of economic and health outcomes in old age, rather than solely access to legal marriage. Nonetheless, findings suggest that individuals in same-sex cohabiting partnerships might experience worse outcomes in old age as a result of cumulative effects across the life course from both the sex of their partner (in the case of female couples) as well as their lack of access to benefits associated with marriage. Accordingly, these findings demonstrate that persons in same-sex cohabiting partnerships require unique policy considerations to address health and economic concerns in old age. Copyright © 2013 Elsevier Inc. All rights reserved.
But the kids are okay: motherhood, consumption and sex work in neo-liberal Latin America.
Rivers-Moore, Megan
2010-12-01
Although sex work remains highly stigmatized around the world, its relatively high value (when compared to other kinds of work available for low-income women) allows sex workers to attain some level of economic, if not social, mobility. This article challenges the idea that sex work in 'third world' settings is always about mere subsistence. Instead, it suggests that sex workers in Costa Rica's tourism sector work to survive, but they also demonstrate significant personal ambition and aim not only to increase their own consumption levels, but crucially to get ahead. Women are clear about what sex work enables for their families and themselves: not the maintenance of the status quo, but rather a level of consumption otherwise unavailable to them as low-income and poor women. Sex work offers an opportunity to consume and to get ahead that these women have been unable to attain in other kinds of employment, primarily domestic and factory work. Furthermore, sex work allows women to think of themselves as particularly good mothers, able to provide for and spend important quality time with their kids. The article argues that survival, consumption, and motherhood are discursively deployed, in often contradictory and conflicting ways, in order to counteract the effects that stigma has on sex workers. It also suggests that sex workers may very well be the quintessential subjects of neo-liberalism in Latin America, in their embrace of entrepreneurial work and consumption.
The human sexual response cycle: brain imaging evidence linking sex to other pleasures.
Georgiadis, J R; Kringelbach, M L
2012-07-01
Sexual behavior is critical to species survival, yet comparatively little is known about the neural mechanisms in the human brain. Here we systematically review the existing human brain imaging literature on sexual behavior and show that the functional neuroanatomy of sexual behavior is comparable to that involved in processing other rewarding stimuli. Sexual behavior clearly follows the established principles and phases for wanting, liking and satiety involved in the pleasure cycle of other rewards. The studies have uncovered the brain networks involved in sexual wanting or motivation/anticipation, as well as sexual liking or arousal/consummation, while there is very little data on sexual satiety or post-orgasmic refractory period. Human sexual behavior also interacts with other pleasures, most notably social interaction and high arousal states. We discuss the changes in the underlying brain networks supporting sexual behavior in the context of the pleasure cycle, the changes to this cycle over the individual's life-time and the interactions between them. Overall, it is clear from the data that the functional neuroanatomy of sex is very similar to that of other pleasures and that it is unlikely that there is anything special about the brain mechanisms and networks underlying sex. Copyright © 2012 Elsevier Ltd. All rights reserved.
School Progress Among Children of Same-Sex Couples.
Watkins, Caleb S
2018-06-01
This study uses logit regressions on a pooled sample of children from the 2012, 2013, and 2014 American Community Survey to perform a nationally representative analysis of school progress for a large sample of 4,430 children who reside with same-sex couples. Odds ratios from regressions that compare children between different-sex married couples and same-sex couples fail to show significant differences in normal school progress between households across a variety of sample compositions. Likewise, marginal effects from regressions that compare children with similar family dynamics between different-sex married couples and same-sex couples fail to predict significantly higher probabilities of grade retention for children of same-sex couples. Significantly lower grade retention rates are sometimes predicted for children of same-sex couples than for different-sex married couples, but these differences are sensitive to sample exclusions and do not indicate causal benefits to same-sex parenting.
Sex as a determinant of type 1 diabetes at diagnosis.
Turtinen, Maaret; Härkönen, Taina; Parkkola, Anna; Ilonen, Jorma; Knip, Mikael
2018-06-03
The present study tested the hypothesis that girls have a more aggressive disease process than boys at the diagnosis of type 1 diabetes (T1D). Demographic and clinical characteristics, the humoral autoantibody profile, and the genetic risk assessed by the presence of human leukocyte antigen DR-DQ haplotypes were analyzed in terms of sex in 4993 children and adolescents diagnosed with T1D between January 2003 and December 2016. A clear male preponderance (56.6%) was observed in our cohort and boys were significantly older than girls at clinical diagnosis (mean 8.3 vs 7.7 years, P < .001). Age-adjusted analyses showed a poorer metabolic decompensation in girls than boys at diagnosis. Boys tested more often positive for autoantibodies against insulin autoantibodies (P = .008), islet antigen-2 autoantibodies (P = .033), and zinc transporter 8 autoantibodies (P = .027), whereas girls had a higher frequency of glutamic acid decarboxylase autoantibodies (GADA) (P < .001) and higher GADA (P < .001) and islet cell antibody titers (P = .001). We did not find any significant differences in the genetic risk profile between girls and boys. Our data show that the metabolic derangement is more severe in girls already at diagnosis of T1D and this finding is independent of age. The immunologic aggressiveness of the disease is more variable as the predominance of different autoantibodies varies between sexes with a higher frequency of GADA in girls, while the 3 other biochemical autoantibodies were more common in boys. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Sex and age differences in the antidepressant-like effect of fluoxetine in the forced swim test.
Fernández-Guasti, Alonso; Olivares-Nazario, Maribel; Reyes, Rebeca; Martínez-Mota, Lucía
2017-01-01
This study compared in males and females of three representative ages: young adults (3-5months old), middle-aged (12-15months old) and senescent (23-25months old) the antidepressant-like effect of fluoxetine (FLX, 5.0 and 10mg/kg) in the forced swim test (FST). Intact (non gonadectomized) rats were evaluated. Young adult females were chosen in proestrus/estrus or in metestrus/diestrus, while middle-aged and senescent females were selected in metestrus/diestrus. Locomotion and motor coordination were also recorded. Under basal conditions (without FLX), young adult and middle-aged females showed less immobility than males. This sex difference disappeared at senescence because males diminished their levels of immobility. Thus, senescent males showed lower immobility than middle-aged and young males. FLX (5 and 10mg/kg) produced similar actions in young females irrespective of their estrous cycle phase, therefore, these subgroups were pooled in a single one. Young adult and middle aged females clearly responded to 5 and 10mg/kg of FLX with a reduction in immobility, while young adult and middle-aged males only did to 10mg/kg. In senescent females 10mg/kg FLX reduced immobility. Remarkably, in senescent males this FLX dose did not produce an antidepressant-like effect. FLX marginally affected locomotion; however, at its highest dose (10mg/kg), and only in senescent males, interfered with motor coordination tested in the rotarod. These data show that sex and aging influence behavioral despair without treatment and after FLX. Copyright © 2016 Elsevier Inc. All rights reserved.
Bray, Freddie Ian; Weiderpass, Elisabete
2010-03-15
Smoking is a major contributor to all-cause mortality in Europe and accounts for one-fifth of the cancer-related deaths. Monitoring the tobacco epidemic via an analysis of lung cancer trends is essential in helping countries arrest the effects of tobacco epidemic in the region. The study aims to provide a comprehensive and up-to-date overview of the temporal patterns of lung cancer mortality in Europe, emphasizing country- and sex-specific differences. National lung cancer mortality data were extracted from the WHO mortality databank by age, sex, year of death (1970-2007) for 36 countries in Europe. Trends in lung cancer mortality in men have tended to decrease in many European countries during the last two decades, particularly in North and Western Europe. Among women, mortality rates are still increasing in many countries, although in a few populations, rates are beginning to stabilize, notably in the high-risk countries within Eastern Europe (Hungary, Poland and the Czech Republic), and in Northern Europe (Denmark, Iceland and the United Kingdom). Men and women are clearly in very different phases of the smoking epidemic, and, as reflected in the mortality rates by birth cohort, the stage varies widely by country within each European region. That lung cancer mortality trends in men are on a downwards path in most European countries while female rates continue to rise, points to an urgent need for national and European prevention strategies that target tobacco cessation and prevention among European women.
Secular trends in the prevalence of dementia and depression in Swedish septuagenarians 1976-2006.
Wiberg, P; Waern, M; Billstedt, E; Ostling, S; Skoog, I
2013-12-01
It is not clear whether the prevalence of dementia and depression among the elderly has changed during the past 30 years. Population-based samples from Gothenburg, Sweden were examined with identical psychiatric and neuropsychiatric examinations at age 70 years in 1976-1977 (n = 404, response rate 78.8%) and 2000-2001 (n = 579, response rate 66.4%), and at age 75 in 1976-1977 (n = 303, response rate 78%) and 2005-2006 (n = 753, response rate 63.4%). Depression was diagnosed according to DSM-IV and dementia according to Kay's criteria. General linear models (GLMs) were used to test for differences between groups. Dementia was related to age but not to birth cohort or sex. Major depression was related to sex (higher in women) but not to birth cohort or age. Minor depression was related to birth cohort, sex (higher in women), age (higher at age 75) and the interaction effect of birth cohort × age; that is, the prevalence of minor depression increased with age in the 2000s but not in the 1970s. Thus, the prevalence of minor depression was higher in 2005-2006 than in 1976-1977 among 75-year-olds for both men (12.4% v. 3.7%) and women (19.1% v. 5.6%) whereas there were no birth cohort differences at age 70. Secular changes were observed only for minor depression, which is considered to be related more to psychosocial factors than major depression. The high prevalence of minor depression in later-born birth cohorts emphasizes the importance of detecting minor depression in the elderly.
Moaref, Ali Reza; Petramfar, Peyman; Aghasadeghi, Kamran; Zamirian, Mahmood; Sharifkazemi, Mohammad Bagher; Rezaian, Shahed; Afifi, Sasan; Zare, Najaf; Rezaian, Gholam Reza
2009-12-01
The association of patent foramen ovale (PFO) and atrial septal aneurysm (ASA) with migraine headache attack (MHA) has been clearly shown. The same findings have been recently demonstrated also in cluster headache. Although tension-type headaches (TTH) are the most common kind of headache, their association with these atrial septal abnormalities has never been studied before. The study was conducted to clarify whether there was a significant association between the presence of such atrial septal abnormalities and tension headache, when compared with migraineurs. One hundred consecutive patients with migraine and 100 age- and sex-matched subjects with TTH and 50 healthy volunteers with no headache were enrolled in the study and underwent a complete transesophageal echocardiographic study with contrast injections at rest and with the Valsalva maneuver. There was no significant difference between the age and the sex of the participants of the three groups. The overall prevalence of PFO was 23% in patients with TTH and that of large PFOs was only 11%. The 23% prevalence of PFO in patients with TTH was not statistically different from 16% found in our normal control group. Furthermore, we found a significantly higher prevalence of PFO in migraineurs (50%) when compared with patients with tension headache (p < 0.001). This was also true for the collective presence of large PFOs and ASAs (35%) (p < 0.001). Although atrial septal anomalies have an association with MHA, they do not have a significant association with TTH.
Luders, Eileen; Toga, Arthur W; Thompson, Paul M
2014-01-01
Numerous studies have demonstrated a sexual dimorphism of the human corpus callosum. However, the question remains if sex differences in brain size, which typically is larger in men than in women, or biological sex per se account for the apparent sex differences in callosal morphology. Comparing callosal dimensions between men and women matched for overall brain size may clarify the true contribution of biological sex, as any observed group difference should indicate pure sex effects. We thus examined callosal morphology in 24 male and 24 female brains carefully matched for overall size. In addition, we selected 24 extremely large male brains and 24 extremely small female brains to explore if observed sex effects might vary depending on the degree to which male and female groups differed in brain size. Using the individual T1-weighted brain images (n=96), we delineated the corpus callosum at midline and applied a well-validated surface-based mesh-modeling approach to compare callosal thickness at 100 equidistant points between groups determined by brain size and sex. The corpus callosum was always thicker in men than in women. However, this callosal sex difference was strongly determined by the cerebral sex difference overall. That is, the larger the discrepancy in brain size between men and women, the more pronounced the sex difference in callosal thickness, with hardly any callosal differences remaining between brain-size matched men and women. Altogether, these findings suggest that individual differences in brain size account for apparent sex differences in the anatomy of the corpus callosum. © 2013.
Luders, Eileen; Toga, Arthur W.; Thompson, Paul M.
2013-01-01
Numerous studies have demonstrated a sexual dimorphism of the human corpus callosum. However, the question remains if sex differences in brain size, which typically is larger in men than in women, or biological sex per se account for the apparent sex differences in callosal morphology. Comparing callosal dimensions between men and women matched for overall brain size may clarify the true contribution of biological sex, as any observed group difference should indicate pure sex effects. We thus examined callosal morphology in 24 male and 24 female brains carefully matched for overall size. In addition, we selected 24 extremely large male brains and 24 extremely small female brains to explore if observed sex effects might vary depending on the degree to which male and female groups differed in brain size. Using the individual T1-weighted brain images (n=96), we delineated the corpus callosum at midline and applied a well-validated surface-based mesh-modeling approach to compare callosal thickness at 100 equidistant points between groups determined by brain size and sex. The corpus callosum was always thicker in men than in women. However, this callosal sex difference was strongly determined by the cerebral sex difference overall. That is, the larger the discrepancy in brain size between men and women, the more pronounced the sex difference in callosal thickness, with hardly any callosal differences remaining between brain-size matched men and women. Altogether, these findings suggest that individual differences in brain size account for apparent sex differences in the anatomy of the corpus callosum. PMID:24064068
Family Structure and Child Health: Does the Sex Composition of Parents Matter?
Reczek, Corinne; Spiker, Russell; Liu, Hui; Crosnoe, Robert
2016-01-01
The children of different-sex married couples appear to be advantaged on a range of outcomes relative to the children of different-sex cohabiting couples. Despite the legalization of same-sex marriage in the United States, whether and how this general pattern extends to the children of same-sex married and cohabiting couples is unknown. This study examines this question with nationally representative data from the 2004–2013 pooled National Health Interview Survey (NHIS). Results reveal that children in cohabiting households have poorer health outcomes than children in married households regardless of the sex composition of their parents. Children in same-sex and different-sex married households are relatively similar to each other on health outcomes, as are children in same-sex and different-sex cohabiting households. These patterns are not fully explained by socioeconomic differences among the four different types of families. This evidence can inform general debates about family structure and child health as well as and policy interventions aiming to reduce child health disparities. PMID:27553617
Family Structure and Child Health: Does the Sex Composition of Parents Matter?
Reczek, Corinne; Spiker, Russell; Liu, Hui; Crosnoe, Robert
2016-10-01
The children of different-sex married couples appear to be advantaged on a range of outcomes relative to the children of different-sex cohabiting couples. Despite the legalization of same-sex marriage in the United States, whether and how this general pattern extends to the children of same-sex married and cohabiting couples is unknown. This study examines this question with nationally representative data from the 2004-2013 pooled National Health Interview Survey (NHIS). Results reveal that children in cohabiting households have poorer health outcomes than children in married households regardless of the sex composition of their parents. Children in same-sex and different-sex married households are relatively similar to each other on health outcomes, as are children in same-sex and different-sex cohabiting households. These patterns are not fully explained by socioeconomic differences among the four different types of families. This evidence can inform general debates about family structure and child health as well as policy interventions aiming to reduce child health disparities.
Why contagious yawning does not (yet) equate to empathy.
Massen, Jorg J M; Gallup, Andrew C
2017-09-01
Various studies and researchers have proposed a link between contagious yawning and empathy, yet the conceptual basis for the proposed connection is not clear and deserves critical evaluation. Therefore, we systematically examined the available empirical evidence addressing this association; i.e., a critical review of studies on inter-individual differences in contagion and self-reported values of empathy, differences in contagion based on familiarity or sex, and differences in contagion among individuals with psychological disorders, as well as developmental research, and brain imaging and neurophysiological studies. In doing so, we reveal a pattern of inconsistent and inconclusive evidence regarding the connection between contagious yawning and empathy. Furthermore, we identify study limitations and confounding variables, such as visual attention and social inhibition. Future research examining links between contagious yawning and empathy requires more rigorous investigation involving objective measurements to explicitly test for this connection. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Wang, Zhe; Chen, Nan; Petrill, Stephen A.; Deater-Deckard, Kirby
2014-01-01
We examined broad dimensions of children’s personalities (total n = 1056; age = 3.5 to 12 years) based on observers’ perceptions following a few hours of structured interaction. Siblings’ behaviors during a two-hour cognitive assessment in the home were rated separately by two different observers. Exploratory and confirmatory factor analyses clearly revealed a two-factor solution in three different samples. There was correspondence between parent-rated temperament and the observer-rated factors. Cross-sectional analyses indicated lower Plasticity among older children and higher Stability among older children. Sex differences were negligible. Plasticity and Stability were correlated in the .2 to .3 range. Most of the sibling similarity in the Plasticity was due to additive genetic influences, whereas most sibling similarity in Stability was attributable to shared environmental influences. The findings implicate a biometric factor structure to childhood personality that fits well with emerging bio-social theories of personality development. PMID:24932065
Sex-based differences in brain alterations across chronic pain conditions
Gupta, Arpana; Mayer, Emeran A; Fling, Connor; Labus, Jennifer S; Naliboff, Bruce D; Hong, Jui-Yang; Kilpatrick, Lisa A
2016-01-01
Common brain mechanisms are thought to play a significant role across a multitude of chronic pain syndromes. In addition, there is strong evidence for the existence of sex differences in the prevalence of chronic pain and in the neurobiology of pain. Thus, it is important to consider sex when developing general principals of pain neurobiology. The goal of the current review is to evaluate what is known about sex-specific brain alterations across multiple chronic pain populations. A total of 15 sex difference and 143 single-sex manuscripts were identified out of 412 chronic pain neuroimaging manuscripts. Results from sex difference studies indicate more prominent primary sensorimotor structural and functional alterations in female chronic pain patients compared to male chronic pain patients; differences in the nature and degree of insula alterations, with greater insula reactivity in male patients; differences in the degree of anterior cingulate structural alterations; and differences in emotional-arousal reactivity. Qualitative comparisons of male-specific and female-specific studies appear to be consistent with the results from sex difference studies. Given these differences, mixed-sex studies of chronic pain risk creating biased data or missing important information and single-sex studies have limited generalizability. The advent of large scale neuroimaging databases will likely aid in building a more comprehensive understanding of sex differences and commonalities in brain mechanisms underlying chronic pain. PMID:27870423
Sex-based differences in brain alterations across chronic pain conditions.
Gupta, Arpana; Mayer, Emeran A; Fling, Connor; Labus, Jennifer S; Naliboff, Bruce D; Hong, Jui-Yang; Kilpatrick, Lisa A
2017-01-02
Common brain mechanisms are thought to play a significant role across a multitude of chronic pain syndromes. In addition, there is strong evidence for the existence of sex differences in the prevalence of chronic pain and in the neurobiology of pain. Thus, it is important to consider sex when developing general principals of pain neurobiology. The goal of the current Mini-Review is to evaluate what is known about sex-specific brain alterations across multiple chronic pain populations. A total of 15 sex difference and 143 single-sex articles were identified from among 412 chronic pain neuroimaging articles. Results from sex difference studies indicate more prominent primary sensorimotor structural and functional alterations in female chronic pain patients compared with male chronic pain patients: differences in the nature and degree of insula alterations, with greater insula reactivity in male patients; differences in the degree of anterior cingulate structural alterations; and differences in emotional-arousal reactivity. Qualitative comparisons of male-specific and female-specific studies appear to be consistent with the results from sex difference studies. Given these differences, mixed-sex studies of chronic pain risk creating biased data or missing important information and single-sex studies have limited generalizability. The advent of large-scale neuroimaging databases will likely aid in building a more comprehensive understanding of sex differences and commonalities in brain mechanisms underlying chronic pain. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Same-sex cohabitors and health: the role of race-ethnicity, gender, and socioeconomic status.
Liu, Hui; Reczek, Corinne; Brown, Dustin
2013-03-01
A legacy of research finds that marriage is associated with good health. Yet same-sex cohabitors cannot marry in most states in the United States and therefore may not receive the health benefits associated with marriage. We use pooled data from the 1997 to 2009 National Health Interview Surveys to compare the self-rated health of same-sex cohabiting men (n = 1,659) and same-sex cohabiting women (n = 1,634) with that of their different-sex married, different-sex cohabiting, and unpartnered divorced, widowed, and never-married counterparts. Results from logistic regression models show that same-sex cohabitors report poorer health than their different-sex married counterparts at the same levels of socioeconomic status. Additionally, same-sex cohabitors report better health than their different-sex cohabiting and single counterparts, but these differences are fully explained by socioeconomic status. Without their socioeconomic advantages, same-sex cohabitors would report similar health to nonmarried groups. Analyses further reveal important racial-ethnic and gender variations.
Mouse model systems to study sex chromosome genes and behavior: relevance to humans
Cox, Kimberly H.; Bonthuis, Paul J.; Rissman, Emilie F.
2014-01-01
Sex chromosome genes directly influence sex differences in behavior. The discovery of the Sry gene on the Y chromosome (Gubbay et al., 1990; Koopman et al., 1990) substantiated the sex chromosome mechanistic link to sex differences. Moreover, the pronounced connection between X chromosome gene mutations and mental illness produces a strong sex bias in these diseases. Yet, the dominant explanation for sex differences continues to be the gonadal hormones. Here we review progress made on behavioral differences in mouse models that uncouple sex chromosome complement from gonadal sex. We conclude that many social and cognitive behaviors are modified by sex chromosome complement, and discuss the implications for human research. Future directions need to include identification of the genes involved and interactions with these genes and gonadal hormones. PMID:24388960
Genes, Environments, and Sex Differences in Alcohol Research.
Salvatore, Jessica E; Cho, Seung Bin; Dick, Danielle M
2017-07-01
The study of sex differences has been identified as one way to enhance scientific reproducibility, and the National Institutes of Health (NIH) have implemented a new policy to encourage the explicit examination of sex differences. Our goal here is to address sex differences in behavioral genetic research on alcohol outcomes. We review sex differences for alcohol outcomes and whether the source and magnitude of genetic influences on alcohol consumption and alcohol use disorder (AUD) are the same across sexes; describe common research designs for studying sex-specific gene-by-environment interaction (G × E) effects; and discuss the role of statistical power and theory when testing sex-specific genetic effects. There are robust sex differences for many alcohol outcomes. The weight of evidence suggests that the source and magnitude of genetic influences on alcohol consumption and AUD are the same across sexes. Whether there are sex-specific G × E effects has received less attention to date. The new NIH policy necessitates a systematic approach for studying sex-specific genetic effects in alcohol research. Researchers are encouraged to report power for tests of these effects and to use theory to develop testable hypotheses, especially for studies of G × E.
Sex Differences in Magical Ideation: A Community-Based Twin Study
Karcher, Nicole R.; Slutske, Wendy S.; Kerns, John G.; Piasecki, Thomas M.; Martin, Nicholas G.
2014-01-01
Two questions regarding sex differences in magical ideation were investigated in this study: (1) whether there are mean level sex differences on the Magical Ideation Scale (MIS), and (2) whether there are quantitative and/or qualitative sex differences in the genetic contributions to variation on this scale. These questions were evaluated using data obtained from a large community sample of adult Australian twins (N=4,355) that included opposite-sex pairs. Participants completed a modified 15-item version of the MIS within a larger assessment battery. Women reported both higher means and variability on the MIS than men; this was also observed within families (in opposite-sex twin pairs). Biometric modeling indicated that the proportion of variation in MIS scores due to genetic influences (indicating quantitative sex differences) and the specific latent genetic contributions to this variation (indicating qualitative sex differences) were the same in men and women. These findings clarify the nature of sex differences in magical ideation and point to avenues for future research. PMID:24364500
Lippa, Richard A
2010-06-01
Using data from over 200,000 participants from 53 nations, I examined the cross-cultural consistency of sex differences for four traits: extraversion, agreeableness, neuroticism, and male-versus-female-typical occupational preferences. Across nations, men and women differed significantly on all four traits (mean ds = -.15, -.56, -.41, and 1.40, respectively, with negative values indicating women scoring higher). The strongest evidence for sex differences in SDs was for extraversion (women more variable) and for agreeableness (men more variable). United Nations indices of gender equality and economic development were associated with larger sex differences in agreeableness, but not with sex differences in other traits. Gender equality and economic development were negatively associated with mean national levels of neuroticism, suggesting that economic stress was associated with higher neuroticism. Regression analyses explored the power of sex, gender equality, and their interaction to predict men's and women's 106 national trait means for each of the four traits. Only sex predicted means for all four traits, and sex predicted trait means much more strongly than did gender equality or the interaction between sex and gender equality. These results suggest that biological factors may contribute to sex differences in personality and that culture plays a negligible to small role in moderating sex differences in personality.
Confidence mediates the sex difference in mental rotation performance.
Estes, Zachary; Felker, Sydney
2012-06-01
On tasks that require the mental rotation of 3-dimensional figures, males typically exhibit higher accuracy than females. Using the most common measure of mental rotation (i.e., the Mental Rotations Test), we investigated whether individual variability in confidence mediates this sex difference in mental rotation performance. In each of four experiments, the sex difference was reliably elicited and eliminated by controlling or manipulating participants' confidence. Specifically, confidence predicted performance within and between sexes (Experiment 1), rendering confidence irrelevant to the task reliably eliminated the sex difference in performance (Experiments 2 and 3), and manipulating confidence significantly affected performance (Experiment 4). Thus, confidence mediates the sex difference in mental rotation performance and hence the sex difference appears to be a difference of performance rather than ability. Results are discussed in relation to other potential mediators and mechanisms, such as gender roles, sex stereotypes, spatial experience, rotation strategies, working memory, and spatial attention.
WHY WE SHOULD CONSIDER SEX (AND STUDY SEX DIFFERENCES) IN ADDICTION RESEARCH
Sanchis-Segura, Carla; Becker, Jill
2017-01-01
Among mammals, every cell has a biological sex, and the sex of an individual pervades its body and brain. In this review we describe the processes through which mammals become phenotypically male or female by organizational and activational influences of genes and hormones throughout development. We emphasized that the molecular and cellular changes triggered by sex chromosomes and steroid hormones may generate sex differences in overt physiological functions and behavior, but they may alternatively promote end-point convergences between males and females. Clinical and preclinical evidence suggest that sex and gender differences modulate drug consumption as well as of the transition towards drug-promoted pathological states such as dependence and addiction. Additionally, sex differences in drug pharmacokinetics and pharmacodynamics will also influence dependence and addiction as well as side effects of drugs. These effects will further interact with socially gendered factors to result in sex differences in the access to, engagement in, and efficacy of any therapeutic attempt. Finally, we maintain that “sex-sameness” is as important as “sex differences” when building a complete understanding of biology for both males and females and provide a framework with which to classify and guide investigation into the mechanisms mediating sex differences and sex-sameness. PMID:27029841
Cui, Z; Hui, M; Liu, Y; Song, C; Li, X; Li, Y; Liu, L; Shi, G; Wang, S; Li, F; Zhang, X; Liu, C; Xiang, J; Chu, K H
2015-01-01
The sex determination system in crabs is believed to be XY-XX from karyotypy, but centromeres could not be identified in some chromosomes and their morphology is not completely clear. Using quantitative trait locus mapping of the gender phenotype, we revealed a ZW-ZZ sex determination system in Eriocheir sinensis and presented a high-density linkage map covering ~98.5% of the genome, with 73 linkage groups corresponding to the haploid chromosome number. All sex-linked markers in the family we used were located on a single linkage group, LG60, and sex linkage was confirmed by genome-wide association studies (GWAS). Forty-six markers detected by GWAS were heterozygous and segregated only in the female parent. The female LG60 was thus the putative W chromosome, with the homologous male LG60 as the Z chromosome. The putative Z and W sex chromosomes were identical in size and carried many homologous loci. Sex ratio (5:1) skewing towards females in induced triploids using unrelated animals also supported a ZW-ZZ system. Transcriptome data were used to search for candidate sex-determining loci, but only one LG60 gene was identified as an ankyrin-2 gene. Double sex- and mab3-related transcription factor 1 (Dmrt1), a Z-linked gene in birds, was located on a putative autosome. With complete genome sequencing and transcriptomic data, more genes on putative sex chromosomes will be characterised, thus leading towards a comprehensive understanding of the sex determination and differentiation mechanisms of E. sinensis, and decapod crustaceans in general. PMID:25873149
Evidence for sex differences in cardiovascular aging and adaptive responses to physical activity.
Parker, Beth A; Kalasky, Martha J; Proctor, David N
2010-09-01
There are considerable data addressing sex-related differences in cardiovascular system aging and disease risk/progression. Sex differences in cardiovascular aging are evident during resting conditions, exercise, and other acute physiological challenges (e.g., orthostasis). In conjunction with these sex-related differences-or perhaps even as an underlying cause-the impact of cardiorespiratory fitness and/or physical activity on the aging cardiovascular system also appears to be sex-specific. Potential mechanisms contributing to sex-related differences in cardiovascular aging and adaptability include changes in sex hormones with age as well as sex differences in baseline fitness and the dose of activity needed to elicit cardiovascular adaptations. The purpose of the present paper is thus to review the primary research regarding sex-specific plasticity of the cardiovascular system to fitness and physical activity in older adults. Specifically, the paper will (1) briefly review known sex differences in cardiovascular aging, (2) detail emerging evidence regarding observed cardiovascular outcomes in investigations of exercise and physical activity in older men versus women, (3) explore mechanisms underlying the differing adaptations to exercise and habitual activity in men versus women, and (4) discuss implications of these findings with respect to chronic disease risk and exercise prescription.
Bos, Henny M W; Kuyper, Lisette; Gartrell, Nanette K
2018-03-01
This investigation compared Dutch same-sex parent and different-sex parent households on children's psychological well-being, parenting stress, and support in child rearing. It was also assessed whether associations among children's well-being, parenting stress, and support in child rearing were different in the two household types. Data were based on a nationally representative survey (N = 25,250). Matching was used to enhance similarity in background characteristics between both types of families. Parental and child characteristics were matched for 43 female same-sex parent, 52 male same-sex parent, and 95 different-sex parent households with offspring between 5 and 18 years old. No significant differences were found on children's well-being, problems in the parent-child relationship, being worried about the child, or the use of formal and informal support between mothers in same-sex and different-sex parent households or for fathers in same-sex and different-sex parent households. Regarding perceived confidence in child rearing, fathers in same-sex parent households and mothers in different-sex parent households felt less competent than their counterparts. Neither the associations between children's well-being and the predictors (parenting stress variables) nor those between support and the predictors (parenting stress and children's well-being) differed along household type. In this population-based study, the similarity in child outcomes regardless of household type confirms the results of prior investigations based on convenience samples. These findings are pertinent to family therapists, practitioners, court officials, and policymakers who seek information on parenting experiences and child outcomes in female and male same-sex parent families. © 2017 Family Process Institute.
Sex Differences in Mental and Behavioral Traits.
ERIC Educational Resources Information Center
Garai, Josef E.; Scheinfeld, Amram
1968-01-01
This review of research conducted on sex differences attempts to answer the following questions: (1) Do the sexes differ in their basic capacities for specific types of mental performance and occupational achievement? (2) If such differences exist, to what extent are they genetically determined? (3) Are sex differences in abilities, interests, and…
Sex Differences in the Presentation of Chronic Low Back Pain
ERIC Educational Resources Information Center
Sheffer, Christine E.; Cassisi, Jeffrey E.; Ferraresi, Laurette M.; Lofland, Kenneth R.; McCracken, Lance M.
2002-01-01
Sex differences in 351 patients with chronic low back pain were examined. Biological, psychological, and psychosocial factors were considered. Sex differences in adaptive functioning were consistent with traditional gender roles. Significant interactions were found for sex and employment status, and sex and marital status. Retired women reported…
Cordaux, Richard; Gilbert, Clément
2017-07-21
An increasing number of horizontal gene transfer (HGT) events from bacteria to animals have been reported in the past years, many of which involve Wolbachia bacterial endosymbionts and their invertebrate hosts. Most transferred Wolbachia genes are neutrally-evolving fossils embedded in host genomes. A remarkable case of Wolbachia HGT for which a clear evolutionary significance has been demonstrated is the " f element", a nuclear Wolbachia insert involved in female sex determination in the terrestrial isopod Armadillidium vulgare . The f element represents an instance of bacteria-to-animal HGT that has occurred so recently that it was possible to infer the donor (feminizing Wolbachia closely related to the w VulC Wolbachia strain of A. vulgare ) and the mechanism of integration (a nearly complete genome inserted by micro-homology-mediated recombination). In this review, we summarize our current knowledge of the f element and discuss arising perspectives regarding female sex determination, unstable inheritance, population dynamics and the molecular evolution of the f element. Overall, the f element unifies three major areas in evolutionary biology: symbiosis, HGT and sex determination. Its characterization highlights the tremendous impact sex ratio distorters can have on the evolution of sex determination mechanisms and sex chromosomes in animals and plants.
The evolutionary stability of cross-sex, cross-trait genetic covariances.
Gosden, Thomas P; Chenoweth, Stephen F
2014-06-01
Although knowledge of the selective agents behind the evolution of sexual dimorphism has advanced considerably in recent years, we still lack a clear understanding of the evolutionary durability of cross-sex genetic covariances that often constrain its evolution. We tested the relative stability of cross-sex genetic covariances for a suite of homologous contact pheromones of the fruit fly Drosophila serrata, along a latitudinal gradient where these traits have diverged in mean. Using a Bayesian framework, which allowed us to account for uncertainty in all parameter estimates, we compared divergence in the total amount and orientation of genetic variance across populations, finding divergence in orientation but not total variance. We then statistically compared orientation divergence of within-sex (G) to cross-sex (B) covariance matrices. In line with a previous theoretical prediction, we find that the cross-sex covariance matrix, B, is more variable than either within-sex G matrix. Decomposition of B matrices into their symmetrical and nonsymmetrical components revealed that instability is linked to the degree of asymmetry. We also find that the degree of asymmetry correlates with latitude suggesting a role for spatially varying natural selection in shaping genetic constraints on the evolution of sexual dimorphism. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.
Bilsky, Sarah A.; Feldner, Matthew T.; Knapp, Ashley A.; Rojas, Sasha M.; Leen-Feldner, Ellen W.
2016-01-01
Evidence suggests that smoking to cope among adolescents is associated with a number of problematic outcomes (e.g., greater smoking frequency, higher rates of dependence). It is thus imperative to better understand factors that may increase the likelihood of smoking to cope among adolescents. Research suggests anxiety sensitivity (AS) is associated with smoking to cope among adults, although the link between AS and coping motives for cigarette use among youth is less clear. Sex differences have also been noted in AS. The current study investigates this association using a biological challenge paradigm. Specifically, the indirect effects of anxious reactivity to bodily arousal on the relation between the physical and mental AS factors and coping motives for cigarette smoking were examined within a sample of 108 adolescent cigarette smokers. Sex was examined as a moderator. Results suggested significant indirect effects of self-reported anxiety in response to bodily arousal on the relation between physical AS and coping motives for cigarette smoking. This indirect effect was moderated by sex, such that it was significant for females but not males. Models examining AS mental concerns and psychophysiological responding to the challenge were not significant. These results suggest that, relative to their low-AS counterparts, female adolescents high in physical concerns respond with elevated anxiety in response to interoceptive arousal and, in turn, endorse elevated coping-related smoking motives. Findings are discussed in terms of implications for understanding the nature and origins of coping-related smoking motives and how such information can be utilized to inform intervention efforts. PMID:27054780
Sun, Yu; Lee, Renick; Chen, Yu; Collinson, Simon; Thakor, Nitish; Bezerianos, Anastasios; Sim, Kang
2015-01-01
Sexual dimorphism in the brain maturation during childhood and adolescence has been repeatedly documented, which may underlie the differences in behaviors and cognitive performance. However, our understanding of how gender modulates the development of structural connectome in healthy adults is still not entirely clear. Here we utilized graph theoretical analysis of longitudinal diffusion tensor imaging data over a five-year period to investigate the progressive gender differences of brain network topology. The brain networks of both genders showed prominent economical "small-world" architecture (high local clustering and short paths between nodes). Additional analysis revealed a more economical "small-world" architecture in females as well as a greater global efficiency in males regardless of scan time point. At the regional level, both increased and decreased efficiency were found across the cerebral cortex for both males and females, indicating a compensation mechanism of cortical network reorganization over time. Furthermore, we found that weighted clustering coefficient exhibited significant gender-time interactions, implying different development trends between males and females. Moreover, several specific brain regions (e.g., insula, superior temporal gyrus, cuneus, putamen, and parahippocampal gyrus) exhibited different development trajectories between males and females. Our findings further prove the presence of sexual dimorphism in brain structures that may underlie gender differences in behavioral and cognitive functioning. The sex-specific progress trajectories in brain connectome revealed in this work provide an important foundation to delineate the gender related pathophysiological mechanisms in various neuropsychiatric disorders, which may potentially guide the development of sex-specific treatments for these devastating brain disorders.
Loza, C M; Scarano, A C; Soibelzon, L H; Negrete, J; Carlini, A A
2015-01-01
The auditory region of pinnipeds has seldom been described. Here we describe and analyze the ontogenetic trajectory of the tympanic bulla of the southern elephant seal, Mirounga leonina (Phocidae, Mammalia). This species is extremely sexually dimorphic and highly polygynous (organized in harems). We examined 118 specimens, arranged in three age classes (CI, CII, and CIII), ranging from newborn to adults (males and females). To analyze the overall size and shape of the tympanic bulla we performed a geometric morphometric analysis including 87 skulls. Females reach definitive shape and size of the bulla at earlier ontogenetic stages than males, in agreement with their earlier involvement in reproductive activities. The internal anatomy of the tympanic region (e.g. form and extension of the paries) does not show remarkable differences between sexes or age classes. The greatest differences between age classes are related to bone thickness, resulting from the apposition of new annual layers. An examination of possible sex-related external differences among age classes shows significant shape differences between males and females in CIII. The morphology observed in neonates is conserved across all individuals from CI, which included specimens up to 1 year old. Clear morphological differences were observed between CI individuals, on one hand, and CII individuals plus CIII females on the other. During cranial development of both male and females, the glenoid cavity expands and compresses the bulla; this condition reaches its maximum expression in CIII males. CIII males showed the greatest morphological differences, with respect to both CI and CII individuals, and CIII females. PMID:25827162
Impact of X/Y genes and sex hormones on mouse neuroanatomy.
Vousden, Dulcie A; Corre, Christina; Spring, Shoshana; Qiu, Lily R; Metcalf, Ariane; Cox, Elizabeth; Lerch, Jason P; Palmert, Mark R
2018-06-01
Biological sex influences brain anatomy across many species. Sex differences in brain anatomy have classically been attributed to differences in sex chromosome complement (XX versus XY) and/or in levels of gonadal sex steroids released from ovaries and testes. Using the four core genotype (4CG) mouse model in which gonadal sex and sex chromosome complement are decoupled, we previously found that sex hormones and chromosomes influence the volume of distinct brain regions. However, recent studies suggest there may be more complex interactions between hormones and chromosomes, and that circulating steroids can compensate for and/or mask underlying chromosomal effects. Moreover, the impact of pre vs post-pubertal sex hormone exposure on this sex hormone/sex chromosome interplay is not well understood. Thus, we used whole brain high-resolution ex-vivo MRI of intact and pre-pubertally gonadectomized 4CG mice to investigate two questions: 1) Do circulating steroids mask sex differences in brain anatomy driven by sex chromosome complement? And 2) What is the contribution of pre- versus post-pubertal hormones to sex-hormone-dependent differences in brain anatomy? We found evidence of both cooperative and compensatory interactions between sex chromosomes and sex hormones in several brain regions, but the interaction effects were of low magnitude. Additionally, most brain regions affected by sex hormones were sensitive to both pre- and post-pubertal hormones. This data provides further insight into the biological origins of sex differences in brain anatomy. Copyright © 2018 Elsevier Inc. All rights reserved.
Stuijfzand, Suzannah; De Wied, Minet; Kempes, Maaike; Van de Graaff, Jolien; Branje, Susan; Meeus, Wim
Although gender differences in affective empathy are well established, evidence of gender differences in the development of affective empathy is inconsistent. Consideration of same-sex versus other-sex affective empathy may assist in elucidating these inconsistencies. Gender differences were investigated in the experience of empathic sadness towards same- versus other-sex targets. The relationships were studied cross-sectionally ( N = 730) and longitudinally ( N = 318) with Dutch adolescents using the empathic sadness scale of the Index of Empathy for Children and Adolescents (IECA; Bryant 1982). In both studies, female adolescents reported more empathic sadness than did male adolescents. Female targets also received more affective empathy than did male targets, and, more importantly, gender differences were observed in same-sex versus other-sex affective empathy. Specifically, in both studies male adolescents reported less empathic sadness towards same-sex than towards other-sex targets. In contrast, female adolescents reported more empathic sadness towards same-sex than towards other-sex targets in the cross-sectional study, and equal levels of empathic sadness towards both types of targets in the longitudinal study. Findings highlight the importance of considering same-sex versus other-sex affective empathy. Gender differences in same-sex and other-sex affective empathy have implications for assisting adolescents in social conflict resolution and interventions for bullying and aggressive behaviour in adolescence using empathy training.
Respiratory sinus arrhythmia responses to cognitive tasks: effects of task factors and RSA indices.
Overbeek, Thérèse J M; van Boxtel, Anton; Westerink, Joyce H D M
2014-05-01
Many studies show that respiratory sinus arrhythmia (RSA) decreases while performing cognitive tasks. However, there is uncertainty about the role of contaminating factors such as physical activity and stress-inducing task variables. Different methods to quantify RSA may also contribute to variable results. In 83 healthy subjects, we studied RSA responses to a working memory task requiring varying levels of cognitive control and a perceptual attention task not requiring strong cognitive control. RSA responses were quantified in the time and frequency domain and were additionally corrected for differences in mean interbeat interval and respiration rate, resulting in eight different RSA indices. The two tasks were clearly differentiated by heart rate and facial EMG reference measures. Cognitive control induced inhibition of RSA whereas perceptual attention generally did not. However, the results show several differences between different RSA indices, emphasizing the importance of methodological variables. Age and sex did not influence the results. Copyright © 2014 Elsevier B.V. All rights reserved.
Sex Role Typing in the Preschool Years: An Overview.
ERIC Educational Resources Information Center
Vroegh, Karen; Handrich, Millicent
Sex role typing in the preschool child is the subject of this research report. Specific topics considered are sex differences, awareness of sex differences, sex role preferences, parent preferences, sex role identification, and family variables related to sex role typing. This summary of research studies in the field reports experimental and…
2013-01-01
Background Tilapia is the common name for a group of cichlid fishes and is one of the most important aquacultured freshwater food fish. Mozambique tilapia and its hybrids, including red tilapia are main representatives of salt tolerant tilapias. A linkage map is an essential framework for mapping QTL for important traits, positional cloning of genes and understanding of genome evolution. Results We constructed a consensus linkage map of Mozambique tilapia and red tilapia using 95 individuals from two F1 families and 401 microsatellites including 282 EST-derived markers. In addition, we conducted comparative mapping and searched for sex-determining loci on the whole genome. These 401 microsatellites were assigned to 22 linkage groups. The map spanned 1067.6 cM with an average inter-marker distance of 3.3 cM. Comparative mapping between tilapia and stickleback, medaka, pufferfish and zebrafish revealed clear homologous relationships between chromosomes from different species. We found evidence for the fusion of two sets of two independent chromosomes forming two new chromosome pairs, leading to a reduction of 24 chromosome pairs in their ancestor to 22 pairs in tilapias. The XY sex determination locus in Mozambique tilapia was mapped on LG1, and verified in five families containing 549 individuals. The major XY sex determination locus in red tilapia was located on LG22, and verified in two families containing 275 individuals. Conclusions A first-generation linkage map of salt tolerant tilapia was constructed using 401 microsatellites. Two separate fusions of two sets of two independent chromosomes may lead to a reduction of 24 chromosome pairs in their ancestor to 22 pairs in tilapias. The XY sex-determining loci from Mozambique tilapia and red tilapia were mapped on LG1 and LG22, respectively. This map provides a useful resource for QTL mapping for important traits and comparative genome studies. The DNA markers linked to the sex-determining loci could be used in the selection of YY males for breeding all-male populations of salt tolerant tilapia, as well as in studies on mechanisms of sex determination in fish. PMID:23356773
Androgen Receptor Signaling in Bladder Cancer
Li, Peng; Chen, Jinbo; Miyamoto, Hiroshi
2017-01-01
Emerging preclinical findings have indicated that steroid hormone receptor signaling plays an important role in bladder cancer outgrowth. In particular, androgen-mediated androgen receptor signals have been shown to correlate with the promotion of tumor development and progression, which may clearly explain some sex-specific differences in bladder cancer. This review summarizes and discusses the available data, suggesting the involvement of androgens and/or the androgen receptor pathways in urothelial carcinogenesis as well as tumor growth. While the precise mechanisms of the functions of the androgen receptor in urothelial cells remain far from being fully understood, current evidence may offer chemopreventive or therapeutic options, using androgen deprivation therapy, in patients with bladder cancer. PMID:28241422
NASA Astrophysics Data System (ADS)
Tabata, Jun; Narai, Yutaka; Sawamura, Nobuo; Hiradate, Syuntaro; Sugie, Hajime
2012-07-01
Mealybugs, which include several agricultural pests, are small sap feeders covered with a powdery wax. They exhibit clear sexual dimorphism; males are winged but fragile and short lived, whereas females are windless and less mobile. Thus, sex pheromones emitted by females facilitate copulation and reproduction by serving as a key navigation tool for males. Although the structures of the hitherto known mealybug pheromones vary among species, they have a common structural motif; they are carboxylic esters of monoterpene alcohols with irregular non-head-to-tail linkages. However, in the present study, we isolated from the Matsumoto mealybug, Crisicoccus matsumotoi (Siraiwa), a pheromone with a completely different structure. Using gas chromatography-mass spectrometry and nuclear magnetic resonance spectroscopy, we identified the pheromone as 3-methyl-3-butenyl 5-methylhexanoate. Its attractiveness to males was confirmed in a series of field trapping experiments involving comparison between the isolated natural product and a synthetic sample. This is the first report of a hemiterpene mealybug pheromone. In addition, the acid moiety (5-methylhexanoate) appears to be rare in insect pheromones.
Bisch-Knaden, Sonja; Daimon, Takaaki; Shimada, Toru; Hansson, Bill S.; Sachse, Silke
2014-01-01
The silkmoth Bombyx mori is the main producer of silk worldwide and has furthermore become a model organism in biological research, especially concerning chemical communication. However, the impact domestication might have had on the silkmoth's olfactory sense has not yet been investigated. Here, we show that the pheromone detection system in B. mori males when compared with their wild ancestors Bombyx mandarina seems to have been preserved, while the perception of environmental odorants in both sexes of domesticated silkmoths has been degraded. In females, this physiological impairment was mirrored by a clear reduction in olfactory sensillum numbers. Neurophysiological experiments with hybrids between wild and domesticated silkmoths suggest that the female W sex chromosome, so far known to have the sole function of determining femaleness, might be involved in the detection of environmental odorants. Moreover, the coding of odorants in the brain, which is usually similar among closely related moths, differs strikingly between B. mori and B. mandarina females. These results indicate that domestication has had a strong impact on odour detection and processing in the olfactory model species B. mori. PMID:24258720
Wijetunga, Charity; Martinez, Ricardo; Rosenfeld, Barry; Cruise, Keith
2018-01-01
The Juvenile Sex Offender Assessment Protocol-Revised (J-SOAP-II) is the most commonly used measure in the assessment of recidivism risk among juveniles who have committed sexual offenses (JSOs), but mixed support exists for its predictive validity. This study compared the predictive validity of the J-SOAP-II across two offender characteristics, age and sexual drive, in a sample of 156 JSOs who had been discharged from a correctional facility or a residential treatment program. The J-SOAP-II appeared to be a better predictor of sexual recidivism for younger JSOs (14-16 years old) than for older ones (17-19 years old), with significant differences found for the Dynamic Summary Scale and Scale III (Intervention). In addition, several of the measure's scales significantly predicted sexual recidivism for JSOs with a clear pattern of sexualized behavior but not for those without such a pattern, indicating that the J-SOAP-II may have greater clinical utility for JSOs with heightened sexual drive. The implications of these findings are discussed.
Protective efficacy of BCG against leprosy in São Paulo.
Lombardi, C; Pedrazzani, E S; Pedrazzani, J C; Filho, P F; Zicker, F
1996-03-01
The case-control study reported here evaluated the protective effect of BCG vaccine against leprosy in São Paulo, Brazil. Seventy-eight patients under age 16 who had been diagnosed as having leprosy (cases) and 385 healthy individuals (controls) were selected and matched by sex, age, place of residence, and type of exposure to leprosy (intradomiciliary or extradomiciliary). The cases were drawn from an active patient registry and from a group of new leprosy cases treated at 50 health centers in the cities of Bauru and Ribeirão Preto in the state of São Paulo. In order to estimate the protective effect of BCG, the prevalences of BCG scars in cases and controls were compared. The presence of one or more scars was associated with an estimated protective efficacy of 90% (95% confidence interval: 78% to 96%). Stratified analysis by age group, sex, socioeconomic level, and clinical form of the disease revealed no significant differences in the protection provided by the vaccine. However, it seems clear that more data will be needed in order to accurately assess the true relevance of BCG for leprosy control programs.
Complex patterns of signalling to convey different social goals of sex in bonobos, Pan paniscus.
Genty, Emilie; Neumann, Christof; Zuberbühler, Klaus
2015-11-05
Sexual behaviour in bonobos (Pan paniscus) functions beyond mere reproduction to mediate social interactions and relationships. In this study, we assessed the signalling behaviour in relation to four social goals of sex in this species: appeasement after conflict, tension reduction, social bonding and reproduction. Overall, sexual behaviour was strongly decoupled from its ancestral reproductive function with habitual use in the social domain, which was accompanied by a corresponding complexity in communication behaviour. We found that signalling behaviour varied systematically depending on the initiator's goals and gender. Although all gestures and vocalisations were part of the species-typical communication repertoire, they were often combined and produced flexibly. Generally, gestures and multi-modal combinations were more flexibly used to communicate a goal than vocalisations. There was no clear relation between signalling behaviour and success of sexual initiations, suggesting that communication was primarily used to indicate the signaller's intention, and not to influence a recipient's willingness to interact sexually. We discuss these findings in light of the larger question of what may have caused, in humans, the evolutionary transition from primate-like communication to language.
Foschi, Martha; Valenzuela, Jerilee
2015-11-01
We use an application-files experimental design to investigate a new topic in the assessment of candidates for junior-engineering jobs. Our focus is on two semi-finalists, a man and a woman, who show clearly different but still good levels of academic record. We keep the gap between those levels constant, but vary the sex category of the better performer. We also include control conditions in which the two have similar records. Each assessor's task was to choose either one applicant or neither, and to rate both in competence and suitability. The control-group competence ratings indicate no gender bias by either men or women; the experimental-conditions competence data are consistent with the candidates' records as predicted, but also show women minimizing the record of the better-performing male candidate. Choice and suitability, on the other hand, reveal a preference for the female applicant across respondents and conditions, as anticipated given the more open nature of those two questions, while still reflecting the academic records. Findings and their interpretation are presented in detail. Copyright © 2015 Elsevier Inc. All rights reserved.
Zou, Jilin
2014-06-01
Prior studies indicate that trait emotional intelligence (EI) is associated negatively with loneliness. However, the mechanisms underlying the relationship are not clear. This study assessed whether both self-esteem and social support mediated the associations between trait EI and loneliness. 469 Chinese undergraduate participants whose age ranged from 18 to 23 years (208 women) were asked to complete four self-report questionnaires, including the Wong Law Emotional Intelligence Scale, the Social and Emotional Loneliness Scale, the Rosenberg Self-esteem Scale, and the Multi-Dimensional Scale of Perceived Social Support. Analyses indicated that self-esteem and social support fully mediated the associations between trait EI and loneliness. Effect contrasts indicated that the specific indirect effect through social support was significantly greater than that through self-esteem. Moreover, a multiple-group analysis indicated that no path differed significantly by sex. These results suggest that social support is more important than self-esteem in the association between trait EI and loneliness. Furthermore, both sexes appear to share the same mechanism underlying this association.
Bisch-Knaden, Sonja; Daimon, Takaaki; Shimada, Toru; Hansson, Bill S; Sachse, Silke
2014-01-07
The silkmoth Bombyx mori is the main producer of silk worldwide and has furthermore become a model organism in biological research, especially concerning chemical communication. However, the impact domestication might have had on the silkmoth's olfactory sense has not yet been investigated. Here, we show that the pheromone detection system in B. mori males when compared with their wild ancestors Bombyx mandarina seems to have been preserved, while the perception of environmental odorants in both sexes of domesticated silkmoths has been degraded. In females, this physiological impairment was mirrored by a clear reduction in olfactory sensillum numbers. Neurophysiological experiments with hybrids between wild and domesticated silkmoths suggest that the female W sex chromosome, so far known to have the sole function of determining femaleness, might be involved in the detection of environmental odorants. Moreover, the coding of odorants in the brain, which is usually similar among closely related moths, differs strikingly between B. mori and B. mandarina females. These results indicate that domestication has had a strong impact on odour detection and processing in the olfactory model species B. mori.
Explaining the sex difference in dyslexia.
Arnett, Anne B; Pennington, Bruce F; Peterson, Robin L; Willcutt, Erik G; DeFries, John C; Olson, Richard K
2017-06-01
Males are diagnosed with dyslexia more frequently than females, even in epidemiological samples. This may be explained by greater variance in males' reading performance. We expand on previous research by rigorously testing the variance difference theory, and testing for mediation of the sex difference by cognitive correlates. We developed an analytic framework that can be applied to group differences in any psychiatric disorder. Males' overrepresentation in the low performance tail of the reading distribution was accounted for by mean and variance differences across sex. There was no sex difference at the high performance tail. Processing speed (PS) and inhibitory control partially mediated the sex difference. Verbal reasoning emerged as a strength in males. Our results complement a previous finding that PS partially mediates the sex difference in symptoms of attention deficit/hyperactivity disorder (ADHD), and helps explain the sex difference in both dyslexia and ADHD and their comorbidity. © 2017 Association for Child and Adolescent Mental Health.
Vanacker, M; Masson, G; Beisel, J-N
2012-03-01
Sampling of the fish community was carried out for 20 years in the Mirgenbach reservoir, in North-Eastern France. The prevalence and the mean intensity of Ligula intestinalis (Cestoda) were analysed in roach (Rutilus rutilus) and silver bream (Blicca bjoerkna) populations, the main two infected species. The aim of this study was to investigate the host switch from roach to silver bream and the consequences of L. intestinalis infestation in silver bream, which is an unusual host for this parasite as Ligula parasitism in silver bream appears to be rare. We analysed in detail the relationships between parasitism index (PI), gonadosomatic index (GSI), perivisceral fat abundance (PFA) and condition index (CI) in the silver bream population. In 1998, prevalence of L. intestinalis highlighted a clear host switch from roach to silver bream. In the silver bream population, young fish were the most severely infected and the impact of plerocercoids appeared to be different depending on the host sex. In male silver bream, plerocercoids drew energy from fat reserves even if GSI was also slightly impacted. On the contrary, in females energy was diverted from gonad maturation rather than from perivisceral fat reserves. No significant difference was observed in terms of CI in either sex.
Richard, Aline; Martin, Brian; Wanner, Miriam; Eichholzer, Monika; Rohrmann, Sabine
2015-02-01
Associations of physical activity with all-cause mortality seem to be quite strong, but little is known about potential effect modifiers as sex, race/ethnicity, age, and obesity. Data of the Third National Health and Nutrition Examination Survey (NHANES III), conducted 1988-1994 with mortality follow-up until 2006, were used to compare mortality risk between different levels of leisure-time physical activity (LTPA) and occupational physical activity (OPA). Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). LTPA (n = 15,307) was inversely associated with all-cause mortality (HR 0.75, 95% CI 0.64-0.88 for regular vs. no LTPA). There was a statistically significant interaction with age (P = .03), with participants over 60 years of age benefitting more from regular or irregular LTPA. OPA was positively associated with all-cause mortality (HR 1.25, 95% CI 0.85-1.84 for high vs. low OPA), particularly among Mexican-Americans (HR 2.28, 95% CI 1.23-4.22); statistically significant interactions were observed for obesity and gender. LTPA clearly predicts all-cause mortality. However, associations between OPA and all-cause mortality are unclear and need further research with special regard to ethnic differences.
Sex differences in stress responses: a critical role for corticotropin-releasing factor.
Bangasser, Debra A; Wiersielis, Kimberly R
2018-03-01
Rates of post-traumatic stress disorder, panic disorder, and major depression are higher in women than in men. Another shared feature of these disorders is that dysregulation of the stress neuropeptide, corticotropin-releasing factor (CRF), is thought to contribute to their pathophysiology. Therefore, sex differences in responses to CRF could contribute to this sex bias in disease prevalence. Here, we review emerging data from non-human animal models that reveal extensive sex differences in CRF functions ranging from its presynaptic regulation to its postsynaptic efficacy. Specifically, detailed are sex differences in the regulation of CRF-containing neurons and the amount of CRF that they produce. We also describe sex differences in CRF receptor expression, distribution, trafficking, and signaling. Finally, we highlight sex differences in the processes that mitigate the effects of CRF. In most cases, the identified sex differences can lead to increased stress sensitivity in females. Thus, the relevance of these differences for the increased risk of depression and anxiety disorders in women compared to men is also discussed.
Tran, Linda Diem
2016-01-01
A difference-in-difference approach was used to compare the effects of same-sex domestic partnership, civil union, and marriage policies on same- and different-sex partners who could have benefitted from their partners’ employer-based insurance (EBI) coverage. Same-sex partners had 78% lower odds (ME=-21%) of having EBI compared to different-sex partners, adjusting for socioeconomic and health-related factors. Same-sex partners living in states that recognized same-sex marriage or domestic partnership had 89% greater odds of having EBI compared to those in states that did not recognize same-sex unions (ME=5%). The impact of same-sex legislation on increasing take-up of dependent EBI coverage among lesbians, gay men, and bisexual individuals (LGBs) was modest, and domestic partnership legislation was equally as effective as same-sex marriage in increasing same-sex partner EBI coverage. Extending dependent EBI coverage to same-sex partners can mitigate gaps in coverage for a segment of the LGB population but will not eliminate them. PMID:26762647
The end of gonad-centric sex determination in mammals
Arnold, Arthur P.
2011-01-01
The 20th century theory of mammalian sex determination states that the embryo is sexually indifferent until the differentiation of gonads, after which sex differences in phenotype are caused by differential effects of gonadal hormones. That theory is inadequate because some sex differences precede differentiation of the gonads and/or are determined by non-gonadal effects of the sexual inequality in number and type of sex chromosomes. A general theory of sex determination is proposed, which recognizes multiple parallel primary sex-determining pathways initiated by genes or factors encoded by the sex chromosomes. The separate sex-specific pathways interact to synergize with or antagonize each other, enhancing or reducing sex differences in phenotype. PMID:22078126
Fernández-de-Larrea, Nerea; Michel, Angelika; Romero, Beatriz; Butt, Julia; Pawlita, Michael; Pérez-Gómez, Beatriz; Castaño-Vinyals, Gemma; Moreno, Victor; Martín, Vicente; Amiano, Pilar; Castilla, Jesús; Fernández-Tardón, Guillermo; Dierssen-Sotos, Trinidad; Clofent, Juan; Alguacil, Juan; Huerta, José María; Jiménez-Moleón, José Juan; Barricarte, Aurelio; Molinuevo, Amaia; Fernández-Villa, Tania; Casabonne, Delphine; Sierra, Ángeles; Kogevinas, Manolis; de Sanjosé, Silvia; Pollán, Marina; Del Campo, Rosa; Waterboer, Tim; Aragonés, Nuria
2017-10-01
Differences in Helicobacter pylori protein expression have been related to the risk of severe gastric diseases. In Spain, a marked geographic pattern in gastric cancer mortality has long been reported. To characterize antibody reactivity patterns against 16 H. pylori proteins, by age, sex, and region of birth, in a large sample of the Spanish adult population. Antibody reactivity was quantified by H. pylori multiplex serology in a sample from the control group of the multicase-control study MCC-Spain. For this analysis, 2555 population-based controls were included. Each participant was classified as seropositive or seronegative for each protein according to specific cutoffs. Overall H. pylori seroprevalence was defined as positivity against ≥4 proteins. Descriptive analyses by age, sex, and region of birth were performed for both seroprevalence and seroreactivity (continuous measure). Differences among groups were tested by logistic and linear regression models. Overall H. pylori seroprevalence increased with age in both sexes. For ages 55-74, seroprevalence was lower in women than in men (84% vs 92%, P<.001). Region of birth explained 7% of the variability in seroprevalence. Among H. pylori seropositive subjects, proteins with the highest seroprevalence were GroEL, NapA, HP231, and Omp. Seropositivity for most of the proteins increased or remained stable with age, rising mainly for CagA, GroEL, and HyuA in women. A clear cohort effect was not observed. This is the first study to describe the antibody patterns against 16 H. pylori proteins in the Spanish population. We found variability in the H. pylori antibody profiles according to both individual factors such as age and sex, and environmental factors such as the region of birth. The slightness of the reduction in seropositivity with decreasing age highlights the ongoing importance of this infection. © 2017 John Wiley & Sons Ltd.
Age-Related Differences in Muscle Fatigue Vary by Contraction Type: A Meta-analysis
Avin, Keith G.
2011-01-01
Background During senescence, despite the loss of strength (force-generating capability) associated with sarcopenia, muscle endurance may improve for isometric contractions. Purpose The purpose of this study was to perform a systematic meta-analysis of young versus older adults, considering likely moderators (ie, contraction type, joint, sex, activity level, and task intensity). Data Sources A 2-stage systematic review identified potential studies from PubMed, CINAHL, PEDro, EBSCOhost: ERIC, EBSCOhost: Sportdiscus, and The Cochrane Library. Study Selection Studies reporting fatigue tasks (voluntary activation) performed at a relative intensity in both young (18–45 years of age) and old (≥55 years of age) adults who were healthy were considered. Data Extraction Sample size, mean and variance outcome data (ie, fatigue index or endurance time), joint, contraction type, task intensity (percentage of maximum), sex, and activity levels were extracted. Data Synthesis Effect sizes were (1) computed for all data points; (2) subgrouped by contraction type, sex, joint or muscle group, intensity, or activity level; and (3) further subgrouped between contraction type and the remaining moderators. Out of 3,457 potential studies, 46 publications (with 78 distinct effect size data points) met all inclusion criteria. Limitations A lack of available data limited subgroup analyses (ie, sex, intensity, joint), as did a disproportionate spread of data (most intensities ≥50% of maximum voluntary contraction). Conclusions Overall, older adults were able to sustain relative-intensity tasks significantly longer or with less force decay than younger adults (effect size=0.49). However, this age-related difference was present only for sustained and intermittent isometric contractions, whereas this age-related advantage was lost for dynamic tasks. When controlling for contraction type, the additional modifiers played minor roles. Identifying muscle endurance capabilities in the older adult may provide an avenue to improve functional capabilities, despite a clearly established decrement in peak torque. PMID:21616932
Dong, Miao; Seemann, Frauke; Humble, Joseph L; Liang, Yimin; Peterson, Drew R; Ye, Rui; Ren, Honglin; Kim, Hui-Su; Lee, Jae-Seong; Au, Doris W T; Lam, Yun Wah
2017-11-01
Growing evidence suggests that the immune system of teleost is vulnerable to xenoestrogens, which are ubiquitous in the marine environment. This study detected and identified the major circulatory immune proteins deregulated by 17α-ethinylestradiol (EE2), which may be linked to fish susceptibility to pathogens in the marine medaka, Oryzias melastigma. Fish immune competence was determined using a host resistance assay to pathogenic bacteria Edwardsiella tarda. Females were consistently more susceptible to infection-induced mortality than males. Exposure to EE2 could narrow the sex gap of mortality by increasing infection-induced death in male fish. Proteomic analysis revealed that the major plasma immune proteins of adult fish were highly sexually dimorphic. EE2 induced pronounced sex-specific changes in the plasma proteome, with the male plasma composition clearly becoming "feminised". Male plasma was found to contain a higher level of fibrinogens, WAP63 and ependymin-2-like protein, which are involved in coagulation, inflammation and regeneration. For the first time, we demonstrated that expression of C1q subunit B (C1Q), an initiating factor of the classical complement pathway, was higher in males and was suppressed in both sexes in response to EE2 and bacterial challenge. Moreover, cleavage and post-translational modification of C3, the central component of the complement system, could be altered by EE2 treatment in males (C3dg down; C3g up). Multiple regression analysis indicated that C1Q is possibly an indicator of fish survival, which warrants further confirmation. The findings support the potential application of plasma immune proteins for prognosis/diagnosis of fish immune competence. Moreover, this study provides the first biochemical basis of the sex-differences in fish immunity and how these differences might be modified by xenoestrogens. Copyright © 2017 Elsevier Ltd. All rights reserved.
Krishnamurthy, Pavan K.; Rajamohamedsait, Hameetha B.; Gonzalez, Veronica; Rajamohamedsait, Wajitha J.; Ahmed, Nawal; Krishnaswamy, Senthilkumar; Sigurdsson, Einar M.
2016-01-01
Type 2 diabetes mellitus is characterized by the deposition of islet amyloid polypeptide (IAPP) as amyloid in islets, a process thought to be toxic to β-cells. To determine the feasibility of targeting these aggregates therapeutically, we vaccinated transgenic (Tg) mice that overexpress human IAPP and were fed a high-fat diet to promote their diabetic phenotype. Our findings indicate that prophylactic vaccination with IAPP and its derivative IAPP7-19-TT, protects wild-type female mice, but not males, from obesity-induced early mortality, and the derivative showed a strong trend for prolonging the lifespan of Tg females but not males. Furthermore, IAPP7-19-TT-immunized Tg females cleared a glucose bolus more efficiently than controls, while IAPP-immunized Tg females showed an impaired ability to clear a glucose bolus compared to their adjuvant injected Tg controls. Interestingly, IAPP or IAPP7-19-TT treatments had no effect on glucose clearance in Tg males. Overall, these beneficial effects of IAPP targeted immunization depend on Tg status, sex, and immunogen. Hence, future studies in this field should carefully consider these variables that clearly affect the therapeutic outcome. In conclusion, IAPP targeting immunotherapy may have benefits in patients with type 2 diabetes. PMID:27379014
Parriault, Marie-Claire; van Melle, Astrid; Basurko, Célia; Gaubert-Marechal, Emilie; Macena, Raimunda Hermelinda Maia; Rogier, Stéphanie; Kerr, Ligia Regina Franco Sansigolo; Nacher, Mathieu
2015-08-01
The border between Brazil and French Guiana is a place of economic, cultural, social and sexual exchange. Female sex workers represent a high risk population for HIV in this area where sexual tourism is particularly developed. HIV testing seems to be an important element in the fight against the epidemic. Indeed, early HIV testing gives access to treatments and prevention. An HIV/AIDS knowledge, attitudes, behaviors and practices survey was conducted in 2011 among sex workers along the border between Brazil and French Guiana. A total of 213 female sex workers were interviewed. One third (31.5%) of the interviewed had never tested for HIV. Factors associated with non HIV-testing were the lack of knowledge of places where to do an HIV test, to be 30 or older, feeling at risk of HIV, not evaluating one's own risk towards HIV, and living in Oiapoque. These results clearly suggest that targeted interventions are needed to encourage and assist female sex workers to get tested regularly.
Herlitz, Agneta; Reuterskiöld, Lena; Lovén, Johanna; Thilers, Petra P; Rehnman, Jenny
2013-01-01
Are cognitive sex differences magnified by individual differences in age, sex hormones, or puberty development? Cross-sectional samples of 12- to 14-year-old boys (n = 85) and girls (n = 102) completed tasks assessing episodic memory, face recognition, verbal fluency, and mental rotations. Blood estradiol, free testosterone, and self-rated puberty scores were obtained. Sex differences were found on all cognitive measures. However, the magnitude was not larger for older children, hormones and cognitive performance were not associated, and early maturers did not perform better than late maturers. Thus, cognitive sex differences were not associated with age, levels of sex hormones, or puberty development.
Rabelo, Ana Gb; Teixeira, Camila Vl; Magalhães, Thamires Nc; Carletti-Cassani, Ana Flávia Mk; Amato Filho, Augusto Cs; Joaquim, Helena Pg; Talib, Leda L; Forlenza, Orestes; Ribeiro, Patrícia Ao; Secolin, Rodrigo; Lopes-Cendes, Iscia; Cendes, Fernando; Balthazar, Marcio Lf
2017-10-01
Introduction The search for a reliable neuroimaging biomarker in Alzheimer's disease is a matter of intense research. The presence of cerebral microbleeds seems to be a potential biomarker. However, it is not clear if the presence of microbleeds has clinical usefulness to differentiate mild Alzheimer's disease and amnestic mild cognitive impairment from normal aging. We aimed to verify if microbleed prevalence differs among three groups: mild Alzheimer's disease, amnestic mild cognitive impairment due to Alzheimer's disease, and normal controls. Moreover, we studied whether microbleeds were associated with apolipoprotein E allele ɛ4 status, cerebrospinal fluid amyloid-beta, total and phosphorylated tau protein levels, vascular factors, and cognition. Methods Twenty-eight mild Alzheimer's disease patients, 34 with amnestic mild cognitive impairment and 36 cognitively normal elderly subjects underwent: magnetic resonance imaging with a susceptibility-weighted imaging sequence on a 3T scanner, apolipoprotein E genotyping and a full neuropsychological evaluation. Only amnestic mild cognitive impairment and mild Alzheimer's disease underwent cerebrospinal fluid analysis. We compared the groups and verified if microbleeds were predicted by all other variables. Results Mild Alzheimer's disease presented a higher prevalence of apolipoprotein E allele ɛ4 in relation to amnestic mild cognitive impairment and control group. No significant differences were found between groups when considering microbleed presence. Logistic regression tests failed to find any relationship between microbleeds and the variables. We performed three different regression models using different independent variables: Model 1 - amyloid-beta, phosphorylated tau protein, total tau, apolipoprotein E allele ɛ4 status, age, and sex; Model 2 - vascular risk factors, age, and sex; Model 3 - cognitive scores sex, age, and education. Conclusion Although microbleeds might be related to the Alzheimer's disease process, their presence is not a good candidate for a neuroimaging biomarker of the disease, especially in its early phases.
A predictive relationship between population and genetic sex ratios in clonal species
NASA Astrophysics Data System (ADS)
McLetchie, D. Nicholas; García-Ramos, Gisela
2017-04-01
Sexual reproduction depends on mate availability that is reflected by local sex ratios. In species where both sexes can clonally expand, the population sex ratio describes the proportion of males, including clonally derived individuals (ramets) in addition to sexually produced individuals (genets). In contrast to population sex ratio that accounts for the overall abundance of the sexes, the genetic sex ratio reflects the relative abundance of genetically unique mates, which is critical in predicting effective population size but is difficult to estimate in the field. While an intuitive positive relationship between population (ramet) sex ratio and genetic (genet) sex ratio is expected, an explicit relationship is unknown. In this study, we determined a mathematical expression in the form of a hyperbola that encompasses a linear to a nonlinear positive relationship between ramet and genet sex ratios. As expected when both sexes clonally have equal number of ramets per genet both sex ratios are identical, and thus ramet sex ratio becomes a linear function of genet sex ratio. Conversely, if sex differences in ramet number occur, this mathematical relationship becomes nonlinear and a discrepancy between the sex ratios amplifies from extreme sex ratios values towards intermediate values. We evaluated our predictions with empirical data that simultaneously quantified ramet and genet sex ratios in populations of several species. We found that the data support the predicted positive nonlinear relationship, indicating sex differences in ramet number across populations. However, some data may also fit the null model, which suggests that sex differences in ramet number were not extensive, or the number of populations was too small to capture the curvature of the nonlinear relationship. Data with lack of fit suggest the presence of factors capable of weakening the positive relationship between the sex ratios. Advantages of this model include predicting genet sex ratio using population sex ratios given known sex differences in ramet number, and detecting sex differences in ramet number among populations.
Mental rotation does not account for sex differences in left-right confusion.
Ocklenburg, Sebastian; Hirnstein, Marco; Ohmann, Hanno Andreas; Hausmann, Markus
2011-06-01
Several studies have demonstrated that women believe they are more prone to left-right confusion (LRC) than men. However, while some studies report that there is also a sex difference in LRC tasks favouring men, others report that men and women perform equally well. Recently, it was suggested that sex differences only emerge in LRC tasks when they involve mental rotation. That is, sex differences that are reported for some LRC tasks are strongly affected by the well-documented male advantage in mental rotation. To test this assumption, 91 participants were investigated on two LRC tasks: The Left-Right Commands Task and the Bergen Left-Right Discrimination Test. Additionally, participants were asked to complete an LRC self-rating questionnaire. To rule out the possibility that sex differences in LRC are confounded by sex differences in mental rotation, male and female participants were matched for mental rotation performance, resulting in a sample of 46 matched participants. These matched participants showed robust sex differences in favour of men in all LRC measurements. This suggests that pronounced sex differences in LRC are a genuine phenomenon that exists independently of sex differences in mental rotation. Copyright © 2011 Elsevier Inc. All rights reserved.
A Research Note on Time With Children in Different- and Same-Sex Two-Parent Families.
Prickett, Kate C; Martin-Storey, Alexa; Crosnoe, Robert
2015-06-01
Public debate on same-sex marriage often focuses on the disadvantages that children raised by same-sex couples may face. On one hand, little evidence suggests any difference in the outcomes of children raised by same-sex parents and different-sex parents. On the other hand, most studies are limited by problems of sample selection and size, and few directly measure the parenting practices thought to influence child development. This research note demonstrates how the 2003-2013 American Time Use Survey (n=44,188) may help to address these limitations. Two-tier Cragg's Tobit alternative models estimated the amount of time that parents in different-sex and same-sex couples engaged in child-focused time. Women in same-sex couples were more likely than either women or men in different-sex couples to spend such time with children. Overall, women (regardless of the gender of their partners) and men coupled with other men spent significantly more time with children than men coupled with women, conditional on spending any child-focused time. These results support prior research that different-sex couples do not invest in children at appreciably different levels than same-sex couples. We highlight the potential for existing nationally representative data sets to provide preliminary insights into the developmental experiences of children in nontraditional families.
Evidence for sex differences in cardiovascular aging and adaptive responses to physical activity
Parker, Beth A.; Kalasky, Martha J.; Proctor, David N.
2010-01-01
There are considerable data addressing sex-related differences in cardiovascular system aging and disease risk/progression. Sex differences in cardiovascular aging are evident during resting conditions, exercise, and other acute physiological challenges (e.g., orthostasis). In conjunction with these sex-related differences—or perhaps even as an underlying cause—the impact of cardiorespiratory fitness and/or physical activity on the aging cardiovascular system also appears to be sex-specific. Potential mechanisms contributing to sex-related differences in cardiovascular aging and adaptability include changes in sex hormones with age as well as sex differences in baseline fitness and the dose of activity needed to elicit cardiovascular adaptations. The purpose of the present paper is thus to review the primary research regarding sex-specific plasticity of the cardiovascular system to fitness and physical activity in older adults. Specifically, the paper will (1) briefly review known sex differences in cardiovascular aging, (2) detail emerging evidence regarding observed cardiovascular outcomes in investigations of exercise and physical activity in older men versus women, (3) explore mechanisms underlying the differing adaptations to exercise and habitual activity in men versus women, and (4) discuss implications of these findings with respect to chronic disease risk and exercise prescription. PMID:20480371
Sex Differences in Technical Communication: A Perspective from Social Role Theory
ERIC Educational Resources Information Center
Thompson, Isabelle
2004-01-01
This article interprets technical communication research about sex differences according to social role theory, which argues that sex differences are enculturated through experiences associated with social positions in the family and the workplace. It reevaluates technical communication research about sex differences in communicative and…
Sex differences in the human brain and the impact of sex chromosomes and sex hormones.
Lentini, E; Kasahara, M; Arver, S; Savic, I
2013-10-01
While there has been increasing support for the existence of cerebral sex differences, the mechanisms underlying these differences are unclear. Based on animal data, it has long been believed that sexual differentiation of the brain is primarily linked to organizational effects of fetal testosterone. This view is, however, in question as more recent data show the presence of sex differences before the onset of testosterone production. The present study focuses on the impact that sex chromosomes might have on these differences. Utilizing the inherent differences in sex and X-chromosome dosage among XXY males, XY males, and XX females, comparative voxel-based morphometry was conducted using sex hormones and sex chromosomes as covariates. Sex differences in the cerebellar and precentral gray matter volumes (GMV) were found to be related to X-chromosome dosage, whereas sex differences in the amygdala, the parahippocamus, and the occipital cortex were linked to testosterone levels. An increased number of sex chromosomes was associated with reduced GMV in the amygdala, caudate, and the temporal and insular cortices, with increased parietal GMV and reduced frontotemporal white matter volume. No selective, testosterone independent, effect of the Y-chromosome was detected. Based on these observations, it was hypothesized that programming of the motor cortex and parts of cerebellum is mediated by processes linked to X-escapee genes, which do not have Y-chromosome homologs, and that programming of certain limbic structures involves testosterone and X-chromosome escapee genes with Y-homologs.
Bos, Henny M W; Knox, Justin R; van Rijn-van Gelderen, Loes; Gartrell, Nanette K
2016-04-01
Using the 2011-2012 National Survey of Children's Health data set, we compared spouse/partner relationships and parent-child relationships (family relationships), parenting stress, and children's general health, emotional difficulties, coping behavior, and learning behavior (child outcomes) in households of same-sex (female) versus different-sex continuously coupled parents with biological offspring. We assessed whether associations among family relationships, parenting stress, and child outcomes were different in the 2 household types. Parental and child characteristics were matched for 95 female same-sex parent and 95 different-sex parent households with children 6 to 17 years old. One parent per household was interviewed by telephone. Multivariate analyses of variance and multiple linear regressions were conducted. No differences were observed between household types on family relationships or any child outcomes. Same-sex parent households scored higher on parenting stress (95% confidence interval = 2.03-2.30) than different-sex parent households (95% confidence interval = 1.76-2.03), p = .006. No significant interactions between household type and family relationships or household type and parenting stress were found for any child outcomes. Children with female same-sex parents and different-sex parents demonstrated no differences in outcomes, despite female same-sex parents reporting more parenting stress. Future studies may reveal the sources of this parenting stress.
Kolla, Nathan J; van der Maas, Mark; Erickson, Patricia G; Mann, Robert E; Seeley, Jane; Vingilis, Evelyn
Attention deficit hyperactivity disorder (ADHD) is often cited as a risk factor for criminality. However, many studies do not take other criminogenic variables into account when reporting on this relationship. It is even less clear whether models that include ADHD as a potential risk factor for criminality consider the importance of sex differences. To answer this question, we collected data from a telephone population survey sampling adults over the age of 18 years in the province of Ontario, Canada (final sample size = 5196). Respondents were screened for ADHD using the Adult ADHD Self-Report Version 1.1 Screener (ASRS-V1.1) and four extra items. Problematic drinking was assessed using the Alcohol Use Disorders Identification Test (AUDIT), while cannabis misuse was evaluated using the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST). The Antisocial Personality Disorder Scale from the Mini-International Neuropsychiatric Interview provided a measure of previous conduct disorder symptoms and the 12-item General Health Questionnaire screening procedure was used to gauge general distress. History of arrest was self-reported. Three separate logistic regression analyses (entire sample, male only, and female only) were applied to estimate the association of the foregoing variables with arrest history. In the combined sample, conduct disorder symptoms, problem alcohol use, and problem cannabis use all predicted history of arrest. With regard to the male sample, conduct disorder symptoms, elevated AUDIT and ASSIST scores, and general distress were associated with an arrest history. For the female subsample, only conduct disorder symptoms and problematic cannabis use showed a relationship with criminality. To summarize, ADHD did not predict history of arrest for either subsample or the combined sample. When comparing males and females, conduct disorder symptoms and cannabis misuse exerted stronger effects on history of arrest for females than males. These results suggest that the relative importance and type of clinical risk factors for arrest may differ according to sex. Such information could be useful for crime prevention policies and correctional programs that take into account differences in experience by sex. Copyright © 2018 Elsevier Ltd. All rights reserved.
Zhao, Liqin; Mao, Zisu; Woody, Sarah K; Brinton, Roberta D
2016-06-01
Despite recent advances in the understanding of clinical aspects of sex differences in Alzheimer's disease (AD), the underlying mechanisms, for instance, how sex modifies AD risk and why the female brain is more susceptible to AD, are not clear. The purpose of this study is to elucidate sex disparities in brain aging profiles focusing on 2 major areas-energy and amyloid metabolism-that are most significantly affected in preclinical development of AD. Total RNA isolated from hippocampal tissues of both female and male 129/C57BL/6 mice at ages of 6, 9, 12, or 15 months were comparatively analyzed by custom-designed Taqman low-density arrays for quantitative real-time polymerase chain reaction detection of a total of 182 genes involved in a broad spectrum of biological processes modulating energy production and amyloid homeostasis. Gene expression profiles revealed substantial differences in the trajectory of aging changes between female and male brains. In female brains, 44.2% of genes were significantly changed from 6 months to 9 months and two-thirds showed downregulation. In contrast, in male brains, only 5.4% of genes were significantly altered at this age transition. Subsequent changes in female brains were at a much smaller magnitude, including 10.9% from 9 months to 12 months and 6.1% from 12 months to 15 months. In male brains, most changes occurred from 12 months to 15 months and the majority were upregulated. Furthermore, gene network analysis revealed that clusterin appeared to serve as a link between the overall decreased bioenergetic metabolism and increased amyloid dyshomeostasis associated with the earliest transition in female brains. Together, results from this study indicate that: (1) female and male brains follow profoundly dissimilar trajectories as they age; (2) female brains undergo age-related changes much earlier than male brains; (3) early changes in female brains signal the onset of a hypometabolic phenotype at risk for AD. These findings provide a mechanistic rationale for female susceptibility to AD and suggest a potential window of opportunity for AD prevention and risk reduction in women. Copyright © 2016 Elsevier Inc. All rights reserved.
Sex differences in learning processes of classical and operant conditioning
Dalla, Christina; Shors, Tracey J.
2009-01-01
Males and females learn and remember differently at different times in their lives. These differences occur in most species, from invertebrates to humans. We review here sex differences as they occur in laboratory rodent species. We focus on classical and operant conditioning paradigms, including classical eyeblink conditioning, fear conditioning, active avoidance and conditioned taste aversion. Sex differences have been reported during acquisition, retention and extinction in most of these paradigms. In general, females perform better than males in the classical eyeblink conditioning, in fear-potentiated startle and in most operant conditioning tasks, such as the active avoidance test. However, in the classical fear conditioning paradigm, in certain lever-pressing paradigms and in the conditioned taste aversion males outperform females or are more resistant to extinction. Most sex differences in conditioning are dependent on organizational effects of gonadal hormones during early development of the brain, in addition to modulation by activational effects during puberty and adulthood. Critically, sex differences in performance account for some of the reported effects on learning and these are discussed throughout the review. Because so many mental disorders are more prevalent on one sex than the other, it is important to consider sex differences in learning when applying animal models of learning for these disorders. Finally, we discuss how sex differences in learning continue to alter the brain throughout the lifespan. Thus, sex differences in learning are not only mediated by sex differences in the brain, but also contribute to them. PMID:19272397
Sex differences in learning processes of classical and operant conditioning.
Dalla, Christina; Shors, Tracey J
2009-05-25
Males and females learn and remember differently at different times in their lives. These differences occur in most species, from invertebrates to humans. We review here sex differences as they occur in laboratory rodent species. We focus on classical and operant conditioning paradigms, including classical eyeblink conditioning, fear-conditioning, active avoidance and conditioned taste aversion. Sex differences have been reported during acquisition, retention and extinction in most of these paradigms. In general, females perform better than males in the classical eyeblink conditioning, in fear-potentiated startle and in most operant conditioning tasks, such as the active avoidance test. However, in the classical fear-conditioning paradigm, in certain lever-pressing paradigms and in the conditioned taste aversion, males outperform females or are more resistant to extinction. Most sex differences in conditioning are dependent on organizational effects of gonadal hormones during early development of the brain, in addition to modulation by activational effects during puberty and adulthood. Critically, sex differences in performance account for some of the reported effects on learning and these are discussed throughout the review. Because so many mental disorders are more prevalent in one sex than the other, it is important to consider sex differences in learning when applying animal models of learning for these disorders. Finally, we discuss how sex differences in learning continue to alter the brain throughout the lifespan. Thus, sex differences in learning are not only mediated by sex differences in the brain, but also contribute to them.
An Association Mapping Framework To Account for Potential Sex Difference in Genetic Architectures.
Kang, Eun Yong; Lee, Cue Hyunkyu; Furlotte, Nicholas A; Joo, Jong Wha J; Kostem, Emrah; Zaitlen, Noah; Eskin, Eleazar; Han, Buhm
2018-05-11
Over the past few years, genome-wide association studies have identified many trait-associated loci that have different effects on females and males, which increased attention to the genetic architecture differences between the sexes. The between-sex differences in genetic architectures can cause a variety of phenomena such as differences in the effect sizes at trait-associated loci, differences in the magnitudes of polygenic background effects, and differences in the phenotypic variances. However, current association testing approaches for dealing with sex, such as including sex as a covariate, cannot fully account for these phenomena and can be suboptimal in statistical power. We present a novel association mapping framework, MetaSex, that can comprehensively account for the genetic architecture differences between the sexes. Through simulations and applications to real data, we show that our framework has superior performance than previous approaches in association mapping. Copyright © 2018, Genetics.
Willoughby, Karen A.; Desrocher, Mary; Levine, Brian; Rovet, Joanne F.
2012-01-01
Few studies have examined both episodic and semantic autobiographical memory (AM) performance during late childhood and early adolescence. Using the newly developed Children’s Autobiographical Interview (CAI), the present study examined the effects of age and sex on episodic and semantic AM and everyday memory in 182 children and adolescents. Results indicated that episodic and semantic AM both improved between 8 and 16 years of age; however, age-related changes were larger for episodic AM than for semantic AM. In addition, females were found to recall more episodic AM details, but not more semantic AM details, than males. Importantly, this sex difference in episodic AM recall was attenuated under conditions of high retrieval support (i.e., the use of probing questions). The ability to clearly visualize past events at the time of recollection was related to children’s episodic AM recall performance, particularly the retrieval of perceptual details. Finally, similar age and sex effects were found between episodic AM and everyday memory ability (e.g., memory for everyday activities). More specifically, older participants and females exhibited better episodic AM and everyday memory performance than younger participants and males. Overall, the present study provides important new insight into both episodic and semantic AM performance, as well as the relation between episodic AM and everyday memory, during late childhood and adolescence. PMID:22403560
Willoughby, Karen A; Desrocher, Mary; Levine, Brian; Rovet, Joanne F
2012-01-01
Few studies have examined both episodic and semantic autobiographical memory (AM) performance during late childhood and early adolescence. Using the newly developed Children's Autobiographical Interview (CAI), the present study examined the effects of age and sex on episodic and semantic AM and everyday memory in 182 children and adolescents. Results indicated that episodic and semantic AM both improved between 8 and 16 years of age; however, age-related changes were larger for episodic AM than for semantic AM. In addition, females were found to recall more episodic AM details, but not more semantic AM details, than males. Importantly, this sex difference in episodic AM recall was attenuated under conditions of high retrieval support (i.e., the use of probing questions). The ability to clearly visualize past events at the time of recollection was related to children's episodic AM recall performance, particularly the retrieval of perceptual details. Finally, similar age and sex effects were found between episodic AM and everyday memory ability (e.g., memory for everyday activities). More specifically, older participants and females exhibited better episodic AM and everyday memory performance than younger participants and males. Overall, the present study provides important new insight into both episodic and semantic AM performance, as well as the relation between episodic AM and everyday memory, during late childhood and adolescence.
Convergent evolution of Y chromosome gene content in flies.
Mahajan, Shivani; Bachtrog, Doris
2017-10-04
Sex-chromosomes have formed repeatedly across Diptera from ordinary autosomes, and X-chromosomes mostly conserve their ancestral genes. Y-chromosomes are characterized by abundant gene-loss and an accumulation of repetitive DNA, yet the nature of the gene repertoire of fly Y-chromosomes is largely unknown. Here we trace gene-content evolution of Y-chromosomes across 22 Diptera species, using a subtraction pipeline that infers Y genes from male and female genome, and transcriptome data. Few genes remain on old Y-chromosomes, but the number of inferred Y-genes varies substantially between species. Young Y-chromosomes still show clear evidence of their autosomal origins, but most genes on old Y-chromosomes are not simply remnants of genes originally present on the proto-sex-chromosome that escaped degeneration, but instead were recruited secondarily from autosomes. Despite almost no overlap in Y-linked gene content in different species with independently formed sex-chromosomes, we find that Y-linked genes have evolved convergent gene functions associated with testis expression. Thus, male-specific selection appears as a dominant force shaping gene-content evolution of Y-chromosomes across fly species.While X-chromosome gene content tends to be conserved, Y-chromosome evolution is dynamic and difficult to reconstruct. Here, Mahajan and Bachtrog use a subtraction pipeline to identify Y-linked genes in 22 Diptera species, revealing patterns of Y-chromosome gene-content evolution.
Lutyk, Dorota; Tagirov, Makhsud; Drobniak, Szymon; Rutkowska, Joanna
2017-12-01
Sexual dimorphism in prenatal development is widespread among vertebrates, including birds. Its mechanism remains unclear, although it has been attributed to the effect of maternal steroid hormones. The aim of this study was to investigate how increased levels of steroid hormones in the eggs influence early embryonic development of male and female offspring. We also asked whether maternal hormones take part in the control of sex-specific expression of the genes involved in prenatal development. We experimentally manipulated hormones' concentrations in the egg yolk by injecting zebra finch females prior to ovulation with testosterone or corticosterone. We assessed growth rate and expression levels of CDK7, FBP1 and GHR genes in 37h-old embryos. We found faster growth and higher expression of two studied genes in male compared to female embryos. Hormonal treatment, despite clearly differentiating egg steroid levels, had no effect on the sex-specific pattern of the embryonic gene expression, even though we confirmed expression of receptors of androgens and glucocorticoids at such an early stage of development. Thus, our study shows high stability of the early sex differences in the embryonic development before the onset of sexual differentiation and indicates their independence of maternal hormones in the egg. Copyright © 2017 Elsevier Inc. All rights reserved.
Thelytokous parthenogenesis in eusocial Hymenoptera.
Rabeling, Christian; Kronauer, Daniel J C
2013-01-01
Female parthenogenesis, or thelytoky, is particularly common in solitary Hymenoptera. Only more recently has it become clear that many eusocial species also regularly reproduce thelytokously, and here we provide a comprehensive overview. Especially in ants, thelytoky underlies a variety of idiosyncratic life histories with unique evolutionary and ecological consequences. In all eusocial species studied, thelytoky probably has a nuclear genetic basis and the underlying cytological mechanism retains high levels of heterozygosity. This is in striking contrast to many solitary wasps, in which thelytoky is often induced by cytoplasmic bacteria and results in an immediate loss of heterozygosity. These differences are likely related to differences in haplodiploid sex determination mechanisms, which in eusocial species usually require heterozygosity for female development. At the same time, haplodiploidy might account for important preadaptations that can help explain the apparent ease with which Hymenoptera transition between sexual and asexual reproduction.
Dinno, Alexis
2014-12-01
In the recent Demography article titled "The Effect of Same-Sex Marriage Laws on Different-Sex Marriage: Evidence From the Netherlands," Trandafir attempted to answer the question, Are rates of opposite sex marriage affected by legal recognition of same-sex marriages? The results of his approach to statistical inference-looking for evidence of a difference in rates of opposite-sex marriage-provide an absence of evidence of such effects. However, the validity of his conclusion of no causal relationship between same-sex marriage laws and rates of opposite-sex marriage is threatened by the fact that Trandafir did not also look for equivalence in rates of opposite-sex marriage in order to provide evidence of an absence of such an effect. Equivalence tests in combination with difference tests are introduced and presented in this article as a more valid inferential approach to the substantive question Trandafir attempted to answer.
Sex-Typed Activities: Cause or Effect?
ERIC Educational Resources Information Center
Carpenter, C. Jan; Huston-Stein, Aletha
Sex differences in activity selection or choice appear by age 12 or 18 months. These choices are one of the earliest indicators of sex differences in the behavior of young children. Differences in activity participation or toy choices are evident long before the emergence of sex differences in personality characteristics like passivity or…
Monitoring and Managing Codling Moth Clearly and Precisely
USDA-ARS?s Scientific Manuscript database
Studies were conducted in two ‘Comice’ pear orchards treated with sex pheromone in southern Oregon to implement the use of site-specific management practices for codling moth. The density of monitoring traps was increased and insecticide sprays were applied based on moth catch thresholds. Only porti...
Sex differences in the psychopharmacological treatment of depression.
Sramek, John J; Murphy, Michael F; Cutler, Neal R
2016-12-01
Although a number of studies have observed that females respond better to serotonergic antidepressants than males and that postmenopausal females have a diminished response to antidepressants compared with younger females, there are also studies that conflict with both of these findings, making any generalizations regarding sex differences difficult to make. Sex variance in antidepressant efficacy and pharmacokinetics profiles have been attributed to sex-based physiological differences, behavioral differences, related disorders, and sex-specific conditions, including pregnancy and menopause. This paper will review the history and current research on sex effects of antidepressant treatment.
Prevalence of major depressive disorder and dementia in psychogeriatric outpatients.
Chinello, A; Grumelli, B; Perrone, C; Annoni, G
2007-01-01
The relationship between depression and dementia in the elderly has been widely investigated, but the real interplay between these variables is still not clear. This observational study highlights the influence of some basic variables, such as sex and age, in the development of dementia and major depression. It shows (i) the importance of sex in the age of onset of depression and dementia, (ii) the presence of two types of depressive syndrome, the first linked to the development of dementia, the second as reactive depression; (iii) the need for more attention to depressive symptoms in young-elderly men.
Furman, Benjamin L S; Evans, Ben J
2018-01-01
Abstract There exists extraordinary variation among species in the degree and nature of sex chromosome divergence. However, much of our knowledge about sex chromosomes is based on comparisons between deeply diverged species with different ancestral sex chromosomes, making it difficult to establish how fast and why sex chromosomes acquire variable levels of divergence. To address this problem, we studied sex chromosome evolution in two species of African clawed frog (Xenopus), both of whom acquired novel systems for sex determination from a recent common ancestor, and both of whom have female (ZW/ZZ) heterogamy. Derived sex chromosomes of one species, X. laevis, have a small region of suppressed recombination that surrounds the sex determining locus, and have remained this way for millions of years. In the other species, X. borealis, a younger sex chromosome system exists on a different pair of chromosomes, but the region of suppressed recombination surrounding an unidentified sex determining gene is vast, spanning almost half of the sex chromosomes. Differences between these sex chromosome systems are also apparent in the extent of nucleotide divergence between the sex chromosomes carried by females. Our analyses also indicate that in autosomes of both of these species, recombination during oogenesis occurs more frequently and in different genomic locations than during spermatogenesis. These results demonstrate that new sex chromosomes can assume radically different evolutionary trajectories, with far-reaching genomic consequences. They also suggest that in some instances the origin of new triggers for sex determination may be coupled with rapid evolution sex chromosomes, including recombination suppression of large genomic regions. PMID:29608717
[Gender: new methodological approaches in guideline development].
Weinbrenner, Susanne; Lönnfors, Sanna; Babitsch, Birgit
2010-01-01
Gender and diversity have a strong impact on health and illness as evidenced by sex and gender differences in the onset and progression of diseases as well as in diagnosis, therapy, and therapeutic outcome. The number of sex/gender-specific studies in medicine has increased steadily in recent years, indicating sex (biological) and gender (social) differences in numerous diseases. Despite this evidence, however, sex/gender differences are rarely considered in medical practice or in health systems, suggesting a delay in transferring such research into evidence-based medical treatment. Similarly, quality improvement guidelines in medical care do not systematically integrate the sex/gender perspective. Against this backdrop, this paper seeks to enumerate the necessary components of a guideline development and evaluation process that systematically integrates sex/gender differences in addition to providing a sex/gender-based methodological approach. The latter is illustrated by a pilot study in which four international guidelines on depression were selected. The sex/gender appropriateness of these guidelines was analysed using two methods: first, sex/gender-relevant words were counted; and second, relevant sex/gender differences were summarised based on a systematic literature review and then compared with the information given in the guidelines. The findings of the pilot study revealed that although strong evidence exists on sex/gender differences in depression, such research was rarely implemented in the guidelines. Given the scope and potential of guidelines to improve the quality of health care, it is essential that they consider the crucial role of sex/gender differences. To date, sex/gender differences have been insufficiently addressed in guideline development and evaluation when they should be an integral component of the process. Copyright © 2010. Published by Elsevier GmbH.
Dumais, Kelly M.; Veenema, Alexa H.
2015-01-01
The neuropeptides vasopressin (VP) and oxytocin (OT) and their receptors in the brain are involved in the regulation of various social behaviors and have emerged as drug targets for the treatment of social dysfunction in several sex-biased neuropsychiatric disorders. Sex differences in the VP and OT systems may therefore be implicated in sex-specific regulation of healthy as well as impaired social behaviors. We begin this review by highlighting the sex differences, or lack of sex differences, in VP and OT synthesis in the brain. We then discuss the evidence showing the presence or absence of sex differences in VP and OT receptors in rodents and humans, as well as showing new data of sexually dimorphic V1a receptor binding in the rat brain. Importantly, we find that there is lack of comprehensive analysis of sex differences in these systems in common laboratory species, and we find that, when sex differences are present, they are highly brain region- and species- specific. Interestingly, VP system parameters (VP and V1aR) are typically higher in males, while sex differences in the OT system are not always in the same direction, often showing higher OT expression in females, but higher OT receptor expression in males. Furthermore, VP and OT receptor systems show distinct and largely non-overlapping expression in the rodent brain, which may cause these receptors to have either complementary or opposing functional roles in the sex-specific regulation of social behavior. Though still in need of further research, we close by discussing how manipulations of the VP and OT systems have given important insights into the involvement of these neuropeptide systems in the sex-specific regulation of social behavior in rodents and humans. PMID:25951955
Dumais, Kelly M; Veenema, Alexa H
2016-01-01
The neuropeptides vasopressin (VP) and oxytocin (OT) and their receptors in the brain are involved in the regulation of various social behaviors and have emerged as drug targets for the treatment of social dysfunction in several sex-biased neuropsychiatric disorders. Sex differences in the VP and OT systems may therefore be implicated in sex-specific regulation of healthy as well as impaired social behaviors. We begin this review by highlighting the sex differences, or lack of sex differences, in VP and OT synthesis in the brain. We then discuss the evidence showing the presence or absence of sex differences in VP and OT receptors in rodents and humans, as well as showing new data of sexually dimorphic V1a receptor binding in the rat brain. Importantly, we find that there is lack of comprehensive analysis of sex differences in these systems in common laboratory species, and we find that, when sex differences are present, they are highly brain region- and species-specific. Interestingly, VP system parameters (VP and V1aR) are typically higher in males, while sex differences in the OT system are not always in the same direction, often showing higher OT expression in females, but higher OT receptor expression in males. Furthermore, VP and OT receptor systems show distinct and largely non-overlapping expression in the rodent brain, which may cause these receptors to have either complementary or opposing functional roles in the sex-specific regulation of social behavior. Though still in need of further research, we close by discussing how manipulations of the VP and OT systems have given important insights into the involvement of these neuropeptide systems in the sex-specific regulation of social behavior in rodents and humans. Copyright © 2015 Elsevier Inc. All rights reserved.
Tran, Linda Diem
2016-12-01
A difference-in-difference approach was used to compare the effects of same-sex domestic partnership, civil union, and marriage policies on same- and different-sex partners who could have benefitted from their partners' employer-based insurance (EBI) coverage. Same-sex partners had 78% lower odds (Marginal Effect = -21%) of having EBI compared with different-sex partners, adjusting for socioeconomic and health-related factors. Same-sex partners living in states that recognized same-sex marriage or domestic partnership had 89% greater odds of having EBI compared with those in states that did not recognize same-sex unions (ME = 5%). The impact of same-sex legislation on increasing take-up of dependent EBI coverage among lesbians, gay men, and bisexual individuals was modest, and domestic partnership legislation was equally as effective as same-sex marriage in increasing same-sex partner EBI coverage. Extending dependent EBI coverage to same-sex partners can mitigate gaps in coverage for a segment of the lesbians, gay men, and bisexual population but will not eliminate them. © The Author(s) 2016.
The origin and evolution of vertebrate sex chromosomes and dosage compensation
Livernois, A M; Graves, J A M; Waters, P D
2012-01-01
In mammals, birds, snakes and many lizards and fish, sex is determined genetically (either male XY heterogamy or female ZW heterogamy), whereas in alligators, and in many reptiles and turtles, the temperature at which eggs are incubated determines sex. Evidently, different sex-determining systems (and sex chromosome pairs) have evolved independently in different vertebrate lineages. Homology shared by Xs and Ys (and Zs and Ws) within species demonstrates that differentiated sex chromosomes were once homologous, and that the sex-specific non-recombining Y (or W) was progressively degraded. Consequently, genes are left in single copy in the heterogametic sex, which results in an imbalance of the dosage of genes on the sex chromosomes between the sexes, and also relative to the autosomes. Dosage compensation has evolved in diverse species to compensate for these dose differences, with the stringency of compensation apparently differing greatly between lineages, perhaps reflecting the concentration of genes on the original autosome pair that required dosage compensation. We discuss the organization and evolution of amniote sex chromosomes, and hypothesize that dosage insensitivity might predispose an autosome to evolving function as a sex chromosome. PMID:22086077
ERIC Educational Resources Information Center
Murphy, Roger J. L.
1978-01-01
Sex differences in GCE 'O' level examination performance are reflected both in the number of boys and girls entering for different subjects and in the numbers obtaining the higher grades. From a review of possible factors, it seems that sex-role stereotyping is the most influential. (Author/SJL)
26 CFR 1.1031(e)-1 - Exchange of livestock of different sexes.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 26 Internal Revenue 11 2012-04-01 2012-04-01 false Exchange of livestock of different sexes. 1.1031(e)-1 Section 1.1031(e)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Exchange of livestock of different sexes. Section 1031(e) provides that livestock of different sexes are...
26 CFR 1.1031(e)-1 - Exchange of livestock of different sexes.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 26 Internal Revenue 11 2013-04-01 2013-04-01 false Exchange of livestock of different sexes. 1.1031(e)-1 Section 1.1031(e)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Exchange of livestock of different sexes. Section 1031(e) provides that livestock of different sexes are...
26 CFR 1.1031(e)-1 - Exchange of livestock of different sexes.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 26 Internal Revenue 11 2011-04-01 2011-04-01 false Exchange of livestock of different sexes. 1.1031(e)-1 Section 1.1031(e)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Exchange of livestock of different sexes. Section 1031(e) provides that livestock of different sexes are...
26 CFR 1.1031(e)-1 - Exchange of livestock of different sexes.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 26 Internal Revenue 11 2014-04-01 2014-04-01 false Exchange of livestock of different sexes. 1.1031(e)-1 Section 1.1031(e)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Exchange of livestock of different sexes. Section 1031(e) provides that livestock of different sexes are...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-12-19
...] Draft Guidance for Industry and Food and Drug Administration Staff; Evaluation of Sex Differences in... entitled ``Evaluation of Sex Differences in Medical Device Clinical Studies.'' This document provides guidance on the study and evaluation of sex differences in medical device clinical trials, with a specific...
Preschoolers' Mental Rotation: Sex Differences in Hemispheric Asymmetry
ERIC Educational Resources Information Center
Hahn, Nicola; Jansen, Petra; Heil, Martin
2010-01-01
Mental rotation performance has been found to produce one of the largest sex differences in cognition accompanied by sex differences in functional cerebral asymmetry. Although sex differences in mental rotation performance can be reliably demonstrated as early as age 5 years old, that is, long before puberty, no data exist as to whether…
The Genetics of Sex Differences in Brain and Behavior
Ngun, Tuck C; Ghahramani, Negar; Sánchez, Francisco J.; Bocklandt, Sven; Vilain, Eric
2010-01-01
Biological differences between men and women contribute to many sex-specific illnesses and disorders. Historically, it was argued that such differences were largely, if not exclusively, due to gonadal hormone secretions. However, emerging research has shown that some differences are mediated by mechanisms other than the action of these hormone secretions and in particular by products of genes located on the X and Y chromosomes, which we refer to as direct genetic effects. This paper reviews the evidence for direct genetic effects in behavioral and brain sex differences. We highlight the `four core genotypes' model and sex differences in the midbrain dopaminergic system, specifically focusing on the role of Sry. We also discuss novel research being done on unique populations including people attracted to the same sex and people with a cross-gender identity. As science continues to advance our understanding of biological sex differences, a new field is emerging that is aimed at better addressing the needs of both sexes: gender-based biology and medicine. Ultimately, the study of the biological basis for sex differences will improve healthcare for both men and women. PMID:20951723
Vallortigara, G; Andrew, R J
1994-12-01
Right hemisphere advantage in individual recognition (as shown by differences between response to strangers and companions) is clear in the domestic chick. Chicks using the left eye (and so, thanks to the complete optic decussation, predominantly the right hemisphere) discriminate between stranger and companion. Chicks using the right eye discriminate less clearly or not at all. The ability of left eyed chicks to respond to differences between strangers and companions stimuli is associated with a more general ability to detect and respond to novelty: this difference between left and right eyed chicks also holds for stimuli which are not social partners. The right hemisphere also shows advantage in tasks with a spatial component (topographical learning; response to change in the spatial context of a stimulus) in the chick, as in humans. Similar specialisations of the two hemispheres are also revealed in tests which involve olfactory cues presented by social partners. The special properties of the left hemisphere are less well established in the chick. Evidence reviewed here suggests that it tends to respond to selected properties of a stimulus and to use them to assign it to a category; such assignment then allows an appropriate response. When exposed to an imprinting stimulus (visual or auditory) a chick begins by using right eye or ear (suggesting left hemisphere control), and then shifts to the left eye or ear (suggesting right hemisphere control), as exposure continues. The left hemisphere here is thus involved whilst behaviour is dominated by vigorous response to releasing stimuli presented by an object. Subsequent learning about the full detailed properties of the stimulus, which is crucial for individual recognition, may explain the shift to right hemisphere control after prolonged exposure to the social stimulus. There is a marked sex difference in choice tests: females tend to choose companions in tests where males choose strangers. It is possible that this difference is specifically caused by stronger motivation to sustain social contact in female chicks, for which there is extensive evidence. However, sex differences in response to change in familiar stimuli are also marked in tests which do not involve social partners. Finally, in both sexes there are two periods during development in which there age-dependent shifts in bias to use one or other hemisphere. These periods (days 3-5 and 8-11) coincide with two major changes in the social behaviour of chicks reared by a hen in a normal brood. It is argued that one function of these periods is to bring fully into play the hemisphere most appropriate to the type of response to, and learning about, social partners which is needed at particular points in development. Parallels are discussed between the involvement of lateralised processes in the recognition of social partners in chicks and humans. Copyright © 1994. Published by Elsevier B.V.
Selective sex differences in declarative memory.
Maitland, Scott B; Herlitz, Agneta; Nyberg, Lars; Bäckman, Lars; Nilsson, Lars-Göran
2004-10-01
Sex invariance of a six-factor, higher order model of declarative memory (two second-order factors: episodic and semantic memory; and four first-order factors: recall, recognition, fluency, and knowledge) was established for 1,796 participants (35-85 years). Metric invariance of first- and second-order factor loadings across sex was demonstrated. At the second-order level, a female advantage was observed for both episodic and semantic memory. At the first-order level, sex differences in episodic memory were apparent for both recall and recognition, whereas the differences in semantic memory were driven by a female superiority in fluency. Additional tests of sex differences in three age groups (35-50, 55-65, and 70-85 years of age) indicated that the female superiority in declarative memory diminished with advancing age. The factor-specific sex differences are discussed in relation to sex differences in hippocampal function.
An Immunohistochemical Approach to Identify the Sex of Young Marine Turtles.
Tezak, Boris M; Guthrie, Kathleen; Wyneken, Jeanette
2017-08-01
Marine turtles exhibit temperature-dependent sex determination (TSD). During critical periods of embryonic development, the nest's thermal environment directs whether an embryo will develop as a male or female. At warmer sand temperatures, nests tend to produce female-biased sex ratios. The rapid increase of global temperature highlights the need for a clear assessment of its effects on sea turtle sex ratios. However, estimating hatchling sex ratios at rookeries remains imprecise due to the lack of sexual dimorphism in young marine turtles. We rely mainly upon laparoscopic procedures to verify hatchling sex; however, in some species, morphological sex can be ambiguous even at the histological level. Recent studies using immunohistochemical (IHC) techniques identified that embryonic snapping turtle (Chelydra serpentina) ovaries overexpressed a particular cold-induced RNA-binding protein in comparison to testes. This feature allows the identification of females vs. males. We modified this technique to successfully identify the sexes of loggerhead sea turtle (Caretta caretta) hatchlings, and independently confirmed the results by standard histological and laparoscopic methods that reliably identify sex in this species. We next tested the CIRBP IHC method on gonad samples from leatherback turtles (Dermochelys coriacea). Leatherbacks display delayed gonad differentiation, when compared to other sea turtles, making hatchling gonads difficult to sex using standard H&E stain histology. The IHC approach was successful in both C. caretta and D. coriacea samples, offering a much-needed tool to establish baseline hatchling sex ratios, particularly for assessing impacts of climate change effects on leatherback turtle hatchlings and sea turtle demographics. Anat Rec, 300:1512-1518, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
Gutzmer, Kyle; Ludwig-Barron, Natasha T; Wyatt, Gail E; Hamilton, Alison B; Stockman, Jamila K
2016-05-01
We examined African American women's experiences of communication with their male intimate partners a couple of hours before and after an incident of unwanted sex. We also examined women's experiences of disclosure following an incident of unwanted sex. Semi-structured qualitative interviews were conducted with a community-based sample of sexually active African American women (n = 19) reporting at least one incident of sexual coercion (i.e., being pressured into unwanted sex without consent) by an intimate male partner since the age of 18. Our analysis was guided by "the sexual division of power" from Connell's (1987) theory of gender and power. Data were analyzed inductively by examining the interviews for common themes in the following domains: communication before the unwanted sex, communication after the unwanted sex, and disclosure to others. Men pressured partners for unwanted sex through verbal and non-verbal tactics, ranging from pestering and blunt requests for sex to verbal bullying and violence. Many women responded by clearly saying no. However, many women also described eventually ceasing to resist their partners and engaging in unwanted sex. After the unwanted sex, men actively and passively avoided discussing the incident. Although many women discussed the unwanted sex with family and friends, less women disclosed to trained professionals. In some cases, women did not discuss the incident with anyone at all. These findings indicate that, when addressing sexual violence against women, there is a need to target men as well as the norms of masculinity that underpin physical and sexual violence against women.
Gutzmer, Kyle; Ludwig-Barron, Natasha T.; Wyatt, Gail E.; Hamilton, Alison B.; Stockman, Jamila K.
2016-01-01
We examined African American women's experiences of communication with their male intimate partners a couple of hours before and after an incident of unwanted sex. We also examined women's experiences of disclosure following an incident of unwanted sex. Semi-structured qualitative interviews were conducted with a community-based sample of sexually active African American women (n=19) reporting at least one incident of sexual coercion (i.e., being pressured into unwanted sex without consent) by an intimate male partner since the age of 18. Our analysis was guided by “the sexual division of power” from the Theory of Gender and Power. Data were analyzed inductively by examining the interviews for common themes in the following domains: communication before the unwanted sex, communication after the unwanted sex, and disclosure to others. Men pressured partners for unwanted sex through verbal and nonverbal tactics, ranging from pestering and blunt requests for sex to verbal bullying and violence. Many women responded by clearly saying no. However, many women also described eventually ceasing to resist their partners and engaging in unwanted sex. After the unwanted sex, men actively and passively avoided discussing the incident. Although many women discussed the unwanted sex with family and friends, less women disclosed to trained professionals. In some cases, women did not discuss the incident with anyone at all. These findings indicate that, when addressing sexual violence against women, there is a need to target men as well as the norms of masculinity that underpin physical and sexual violence against women. PMID:26892099
Parent-Adolescent Sexual Communication and Adolescent Safer Sex Behavior: A Meta-Analysis.
Widman, Laura; Choukas-Bradley, Sophia; Noar, Seth M; Nesi, Jacqueline; Garrett, Kyla
2016-01-01
Parent-adolescent sexual communication has received considerable attention as a factor that can positively affect safer sex behavior among youth; however, the evidence linking such communication to youth contraceptive and condom use has not been empirically synthesized. To examine the effect of parent-adolescent sexual communication on safer sex behavior among youth and explore potential moderators of this association. A systematic search of studies published from database inception through June 30, 2014, using the MEDLINE, PsycINFO, and Communication & Mass Media Complete databases and relevant review articles yielded 5098 studies, of which 52 studies with 25,314 adolescents met the study eligibility criteria. Analysis was conducted from July 1, 2014, to July 27, 2015. Studies were included if they sampled adolescents (mean sample age ≤18 years), included an adolescent report of sexual communication with one or both parents, measured safer sex behavior, and were published in English. Correlation coefficients (r) and 95% CIs were computed from studies and meta-analyzed using random-effects models. Safer sex behavior, including use of contraceptives or condoms. Fifty-two articles, including 71 independent effects representing more than 3 decades of research on 25,314 adolescents (weighted mean age, 15.2 years) were synthesized. Across studies, there was a significant weighted mean effect (r = 0.10; 95% CI, 0.08-0.13) linking parent-adolescent sexual communication with safer sex behavior, which was statistically heterogeneous (Q = 203.50, P < .001, I2 = 65.60). Moderation analyses revealed larger effects for communication with girls (r = 0.12) than boys (r = 0.04) and among youth who discussed sex with their mothers (r = 0.14) compared with their fathers (r = 0.03). Effects did not differ for contraceptive vs condom use or among longitudinal vs cross-sectional studies, indicating that parent sexual communication had a similar effect across study designs and outcomes. Several methodological issues were identified in the literature; future studies can improve on these issues by measuring parent-adolescent communication with robust, multi-item measures, clearly specifying the target parent, and applying multimethod longitudinal designs. Sexual communication with parents, particularly mothers, plays a small protective role in safer sex behavior among adolescents; this protective effect is more pronounced for girls than boys. We discuss the implications for practice and make suggestions for future research on parent-adolescent sexual communication.
Parent-Adolescent Sexual Communication and Adolescent Safer Sex Behavior: A Meta-Analysis
Widman, Laura; Choukas-Bradley, Sophia; Noar, Seth M.; Nesi, Jacqueline; Garrett, Kyla
2016-01-01
Importance Parent-adolescent sexual communication has received considerable attention as one factor that can positively impact safer sex among youth; however, the evidence linking communication to youth contraceptive and condom use has not been empirically synthesized. Objective This meta-analysis examined the effect of parent-adolescent sexual communication on youth safer sex behavior and explored potential moderators of this association. Data Sources A systematic search was conducted of studies published through June 2014 using Medline, PsycINFO, and Communication & Mass Media Complete databases and relevant review articles. Study Selection Studies were included if they: 1) sampled adolescents (mean sample age≤18); 2) included an adolescent report of sexual communication with parent(s); 3) measured safer sex behavior; and 4) were published in English. Data Extraction and Synthesis Correlation coefficients (r) and 95% confidence intervals (CIs) were computed from studies and meta-analyzed using random-effects models. Main Outcomes and Measures The primary outcome was safer sex behavior, including use of contraceptives/birth control or condoms. Results Seventy-one independent effects representing over three decades of research on 25,314 adolescents (mean age = 15.1) were synthesized. Across studies, there was a small, significant weighted mean effect (r = .10, [95% CI:0.08–0.13]) linking parent-adolescent sexual communication to safer sex behavior, which was statistically heterogeneous (Q = 203.50, p < .001, I2 = 65.60). Moderation analyses revealed larger effects for communication with girls (r = .12) than boys (r = .04), and among youth who discussed sex with mothers (r = .14) compared to fathers (r = .03). Effects did not differ for contraceptive versus condom use, or among longitudinal versus cross-sectional studies, indicating parent sexual communication had a similar impact across study designs and outcomes. Several methodological issues were identified in the literature; future studies can improve on these by measuring parent-adolescent communication with robust, multi-item measures, clearly specifying the target parent, and applying multi-method longitudinal designs. Conclusions and Relevance Sexual communication with parents, particularly mothers, plays a small protective role in adolescent safer sex behavior, and this protective effect is more pronounced for girls than boys. Implications for practice and suggestions for future research on parent-adolescent communication are discussed. PMID:26524189
Attitudes towards same-sex marriage in Portugal: predictors and scale validation.
de Oliveira, João Manuel; Lopes, Diniz; Cameira, Miguel; Nogueira, Conceição
2014-12-19
The goal of the present research was to validate a Portuguese version of Pearl and Galupo's (2007) Attitudes toward Same-Sex Marriage Scale (ATSM). Participants were 1,402 heterosexual men and women that completed an on-line questionnaire. The final 15-item scale formed a single factor showing high internal consistency (α = .95). This one factor structure was backed-up by a confirmatory factorial analysis. In a general way, the results indicate a clearly positive attitude toward same-sex marriage (overall mean was 63.79, SD = 12.66, above the scale mid-point, t(1401) = 55.55, p < .001). Furthermore, analysis of the scale's predictors demonstrates how a left-wing orientation (β = .22, p < .001) and the level of denial of deservingness for lesbian/gay discrimination (β = .30, p < .001) prove to be the best predictors of attitudes towards same-sex marriage. On the whole, these results indicate that the Portuguese ATSM version is a reliable instrument for carrying out scientific research and measuring and monitoring public opinion on this subject.
Ballonoff Suleiman, Ahna; Johnson, Megan; Shirtcliff, Elizabeth A; Galván, Adriana
2015-08-01
Many school-based abstinence-only sex education curricula state that sexual activity outside of marriage is likely to have harmful psychological effects. Recent advances in neuroscience have expanded our understanding of the neural underpinnings of romantic love, marriage, sexual desire, and sexual behavior and improved our understanding of adolescent brain development. In this article, we review recent advances in neuroscience and clarify what is known about the link between neural development and adolescent romantic and sexual behavior and what opportunities exist for future research. Whereas the evidence from neuroscience does not yet allow for clear conclusions about the cost or benefits of early romantic relationships and sexual behavior, it does indicate that providing developmentally appropriate education contributes to lifelong sexual health. Developing policies and practices for school-based sex education that reflect current research will best support the sexual and reproductive health of adolescents throughout their lives. © 2015, American School Health Association.
Separated by Sex: A Critical Look at Single-Sex Education for Girls (edited by Susan Morse)
NASA Astrophysics Data System (ADS)
Ceraulo, Reviewed By Sandra C.
1999-05-01
As Cornelius Riordan states in his round-table paper, "The challenge of effective and equitable schooling in the next century is to overcome the resistance and recalcitrance of youth cultures in and out of school" (p 58). While this is admittedly not a new problem, it is more complex in its modern form and innovative ways to solve it are needed. In an old tradition, one such attempt has been single-sex schools, which have had particular success with the disadvantaged and white females in American society, with the notable involvement of Catholic religious communities. The report does not make clear whether their successes can be reproduced in some modification of the public school format. However, the AAUW report on single-sex schools sheds light on some of the characteristics that make true learning communities out of ordinary schools and on what it takes to reach disadvantaged girls. For these reasons, the AAUW report is good reading for educators at all levels.
Targeted metabolomic profiling in rat tissues reveals sex differences.
Ruoppolo, Margherita; Caterino, Marianna; Albano, Lucia; Pecce, Rita; Di Girolamo, Maria Grazia; Crisci, Daniela; Costanzo, Michele; Milella, Luigi; Franconi, Flavia; Campesi, Ilaria
2018-03-16
Sex differences affect several diseases and are organ-and parameter-specific. In humans and animals, sex differences also influence the metabolism and homeostasis of amino acids and fatty acids, which are linked to the onset of diseases. Thus, the use of targeted metabolite profiles in tissues represents a powerful approach to examine the intermediary metabolism and evidence for any sex differences. To clarify the sex-specific activities of liver, heart and kidney tissues, we used targeted metabolomics, linear discriminant analysis (LDA), principal component analysis (PCA), cluster analysis and linear correlation models to evaluate sex and organ-specific differences in amino acids, free carnitine and acylcarnitine levels in male and female Sprague-Dawley rats. Several intra-sex differences affect tissues, indicating that metabolite profiles in rat hearts, livers and kidneys are organ-dependent. Amino acids and carnitine levels in rat hearts, livers and kidneys are affected by sex: male and female hearts show the greatest sexual dimorphism, both qualitatively and quantitatively. Finally, multivariate analysis confirmed the influence of sex on the metabolomics profiling. Our data demonstrate that the metabolomics approach together with a multivariate approach can capture the dynamics of physiological and pathological states, which are essential for explaining the basis of the sex differences observed in physiological and pathological conditions.
Gordon, Elizabeth A.; Corbitt, Cynthia
2015-01-01
Sex differences in social behaviors exist in mammals during adulthood, and further evidence suggests that sex differences in behavior are present before sexual maturity. In order to model behavioral disorders in animals, it is important to assess baseline sex-related behavioral differences, especially when studying disorders for which sex-related behavioral effects are expected. We investigated the effect of sex on behavior in 3 strains of pre-pubertal mice (C57BL/6, CFW, and CF1) using a wheel-running assay. We found no significant sex differences in latency to run on the wheel or total duration of wheel running within each strain. During the social interaction test, there were no differences between sexes in latency or total duration of contact or following between a subject and novel mouse. We also evaluated behavioral patterns of wheel running and stereotypical behaviors, such as burrowing and grooming. Both sexes showed characteristic wheel running behavior, spending the majority of each trial interacting with the wheel when it was free and more time performing other activities (e.g., stereotypical behaviors, general locomotion) when it was jammed. These results provide evidence that, among various strains of pre-pubertal mice, baseline sex-related behavioral differences are not strong enough to influence the measured behaviors. PMID:26316671