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Sample records for sex-specific fitness returns

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

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

    2015-11-01

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

  2. Assured fitness returns in a social wasp with no worker caste.

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    Lucas, Eric R; Field, Jeremy

    2011-10-07

    The theory of assured fitness returns proposes that individuals nesting in groups gain fitness benefits from effort expended in brood-rearing, even if they die before the young that they have raised reach independence. These benefits, however, require that surviving nest-mates take up the task of rearing these young. It has been suggested that assured fitness returns could have favoured group nesting even at the origin of sociality (that is, in species without a dedicated worker caste). We show that experimentally orphaned brood of the apoid wasp Microstigmus nigrophthalmus continue to be provisioned by surviving adults for at least two weeks after the orphaning. This was the case for brood of both sexes. There was no evidence that naturally orphaned offspring received less food than those that still had mothers in the nest. Assured fitness returns can therefore represent a real benefit to nesting in groups, even in species without a dedicated worker caste.

  3. The contribution of the mitochondrial genome to sex-specific fitness variance.

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    Smith, Shane R T; Connallon, Tim

    2017-05-01

    Maternal inheritance of mitochondrial DNA (mtDNA) facilitates the evolutionary accumulation of mutations with sex-biased fitness effects. Whereas maternal inheritance closely aligns mtDNA evolution with natural selection in females, it makes it indifferent to evolutionary changes that exclusively benefit males. The constrained response of mtDNA to selection in males can lead to asymmetries in the relative contributions of mitochondrial genes to female versus male fitness variation. Here, we examine the impact of genetic drift and the distribution of fitness effects (DFE) among mutations-including the correlation of mutant fitness effects between the sexes-on mitochondrial genetic variation for fitness. We show how drift, genetic correlations, and skewness of the DFE determine the relative contributions of mitochondrial genes to male versus female fitness variance. When mutant fitness effects are weakly correlated between the sexes, and the effective population size is large, mitochondrial genes should contribute much more to male than to female fitness variance. In contrast, high fitness correlations and small population sizes tend to equalize the contributions of mitochondrial genes to female versus male variance. We discuss implications of these results for the evolution of mitochondrial genome diversity and the genetic architecture of female and male fitness. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  4. Persistent sex-by-environment effects on offspring fitness and sex-ratio adjustment in a wild bird population.

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    Bowers, E Keith; Thompson, Charles F; Sakaluk, Scott K

    2015-03-01

    A major component of sex-allocation theory, the Trivers-Willard model (TWM), posits that sons and daughters are differentially affected by variation in the rearing environment. In many species, the amount of parental care received is expected to have differing effects on the fitness of males and females. When this occurs, the TWM predicts that selection should favour adjustment of the offspring sex ratio in relation to the expected fitness return from offspring. However, evidence for sex-by-environment effects is mixed, and little is known about the adaptive significance of producing either sex. Here, we test whether offspring sex ratios vary according to predictions of the TWM in the house wren (Troglodytes aedon, Vieillot). We also test the assumption of a sex-by-environment effect on offspring using two experiments, one in which we manipulated age differences among nestlings within broods, and another in which we held nestling age constant but manipulated brood size. As predicted, females with high investment ability overproduced sons relative to those with lower ability. Males were also overproduced early within breeding seasons. In our experiments, the body mass of sons was more strongly affected by the sibling-competitive environment and resource availability than that of daughters: males grew heavier than females when reared in good conditions but were lighter than females when in poor conditions. Parents rearing broods with 1:1 sex ratios were more productive than parents rearing broods biased more strongly towards sons or daughters, suggesting that selection favours the production of mixed-sex broods. However, differences in the condition of offspring as neonates persisted to adulthood, and their reproductive success as adults varied with the body mass of sons, but not daughters, prior to independence from parental care. Thus, selection should favour slight but predictable variations in the sex ratio in relation to the quality of offspring that parents are

  5. Community-Based Colorectal Cancer Screening in a Rural Population: Who Returns Fecal Immunochemical Test (FIT) Kits?

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    Crosby, Richard A; Stradtman, Lindsay; Collins, Tom; Vanderpool, Robin

    2017-09-01

    To determine the return rate of community-delivered fecal immunochemical test (FIT) kits in a rural population and to identify significant predictors of returning kits. Residents were recruited in 8 rural Kentucky counties to enroll in the study and receive an FIT kit. Of 345 recruited, 82.0% returned an FIT kit from the point of distribution. These participants were compared to the remainder relative to age, sex, marital status, having an annual income below $15,000, not graduating from high school, not having a regular health care provider, not having health care coverage, being a current smoker, indicating current overweight or obese status, and a scale measure of fatalism pertaining to colorectal cancer. Predictors achieving significance at the bivariate level were entered into a stepwise logistic regression model to calculate adjusted OR and 95% CI. The return rate was 82.0%. In adjusted analyses, those indicating an annual income of less than $15,000 were 2.85 times more likely to return their kits (95% CI: 1.56-5.24; P < .001). Also, those not perceiving themselves to be overweight/obese were 1.95 times more likely to return their kits (95% CI: 1.07-3.55; P = .029). An outreach-based colorectal cancer screening program in a rural population may yield high return rates. People with annual incomes below $15,000 and those not having perceptions of being overweight/obese may be particularly likely to return FIT kits. © 2016 National Rural Health Association.

  6. Epigenetics and sex-specific fitness: an experimental test using male-limited evolution in Drosophila melanogaster.

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    Abbott, Jessica K; Innocenti, Paolo; Chippindale, Adam K; Morrow, Edward H

    2013-01-01

    When males and females have different fitness optima for the same trait but share loci, intralocus sexual conflict is likely to occur. Epigenetic mechanisms such as genomic imprinting (in which expression is altered according to parent-of-origin) and sex-specific maternal effects have been suggested as ways by which this conflict can be resolved. However these ideas have not yet been empirically tested. We designed an experimental evolution protocol in Drosophila melanogaster that enabled us to look for epigenetic effects on the X-chromosome-a hotspot for sexually antagonistic loci. We used special compound-X females to enforce father-to-son transmission of the X-chromosome for many generations, and compared fitness and gene expression levels between Control males, males with a Control X-chromosome that had undergone one generation of father-son transmission, and males with an X-chromosome that had undergone many generations of father-son transmission. Fitness differences were dramatic, with experimentally-evolved males approximately 20% greater than controls, and with males inheriting a non-evolved X from their father about 20% lower than controls. These data are consistent with both strong intralocus sexual conflict and misimprinting of the X-chromosome under paternal inheritance. However, expression differences suggested that reduced fitness under paternal X inheritance was largely due to deleterious maternal effects. Our data confirm the sexually-antagonistic nature of Drosophila's X-chromosome and suggest that the response to male-limited X-chromosome evolution entails compensatory evolution for maternal effects, and perhaps modification of other epigenetic effects via coevolution of the sex chromosomes.

  7. Sex recombination, and reproductive fitness: an experimental study using Paramecium

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    Nyberg, D.

    1982-08-01

    The effect of sex and recombination on reproductive fitness are measured using five wild stocks of Paramecium primaurelia. Among the wild stocks there were highly significant differences in growth rates. No hybrid had as low a fitness as the least fit parental stock. Recombination produced genotypes of higher fitness than those of either parent only in the cross between the two stocks of lowest fitness. The increase in variance of fitness as a result of recombination was almost exclusively attributable to the generation lines with low fitness. The fitness consequences of sexuality and mate choice were stock specific; some individuals leaving the most descendants by inbreeding, others by outcrossing. For most crosses the short-term advantage of sex, if any, accrue from the fusion of different gametes (hybrid vigor) and not from recombination. Since the homozygous genotype with the highest fitnes left the most progeny by inbreeding (no recombination), the persistence of conjugation in P. primaurelia is paradoxical. (JMT)

  8. Sex-specific selection under environmental stress in seed beetles.

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    Martinossi-Allibert, I; Arnqvist, G; Berger, D

    2017-01-01

    Sexual selection can increase rates of adaptation by imposing strong selection in males, thereby allowing efficient purging of the mutation load on population fitness at a low demographic cost. Indeed, sexual selection tends to be male-biased throughout the animal kingdom, but little empirical work has explored the ecological sensitivity of this sex difference. In this study, we generated theoretical predictions of sex-specific strengths of selection, environmental sensitivities and genotype-by-environment interactions and tested them in seed beetles by manipulating either larval host plant or rearing temperature. Using fourteen isofemale lines, we measured sex-specific reductions in fitness components, genotype-by-environment interactions and the strength of selection (variance in fitness) in the juvenile and adult stage. As predicted, variance in fitness increased with stress, was consistently greater in males than females for adult reproductive success (implying strong sexual selection), but was similar in the sexes in terms of juvenile survival across all levels of stress. Although genetic variance in fitness increased in magnitude under severe stress, heritability decreased and particularly so in males. Moreover, genotype-by-environment interactions for fitness were common but specific to the type of stress, sex and life stage, suggesting that new environments may change the relative alignment and strength of selection in males and females. Our study thus exemplifies how environmental stress can influence the relative forces of natural and sexual selection, as well as concomitant changes in genetic variance in fitness, which are predicted to have consequences for rates of adaptation in sexual populations. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

  9. Sexual selection on spontaneous mutations strengthens the between-sex genetic correlation for fitness.

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    Allen, Scott L; McGuigan, Katrina; Connallon, Tim; Blows, Mark W; Chenoweth, Stephen F

    2017-10-01

    A proposed benefit to sexual selection is that it promotes purging of deleterious mutations from populations. For this benefit to be realized, sexual selection, which is usually stronger on males, must purge mutations deleterious to both sexes. Here, we experimentally test the hypothesis that sexual selection on males purges deleterious mutations that affect both male and female fitness. We measured male and female fitness in two panels of spontaneous mutation-accumulation lines of the fly, Drosophila serrata, each established from a common ancestor. One panel of mutation accumulation lines limited both natural and sexual selection (LS lines), whereas the other panel limited natural selection, but allowed sexual selection to operate (SS lines). Although mutation accumulation caused a significant reduction in male and female fitness in both the LS and SS lines, sexual selection had no detectable effect on the extent of the fitness reduction. Similarly, despite evidence of mutational variance for fitness in males and females of both treatments, sexual selection had no significant impact on the amount of mutational genetic variance for fitness. However, sexual selection did reshape the between-sex correlation for fitness: significantly strengthening it in the SS lines. After 25 generations, the between-sex correlation for fitness was positive but considerably less than one in the LS lines, suggesting that, although most mutations had sexually concordant fitness effects, sex-limited, and/or sex-biased mutations contributed substantially to the mutational variance. In the SS lines this correlation was strong and could not be distinguished from unity. Individual-based simulations that mimick the experimental setup reveal two conditions that may drive our results: (1) a modest-to-large fraction of mutations have sex-limited (or highly sex-biased) fitness effects, and (2) the average fitness effect of sex-limited mutations is larger than the average fitness effect of

  10. Developmental trajectories of paediatric headache - sex-specific analyses and predictors.

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    Isensee, Corinna; Fernandez Castelao, Carolin; Kröner-Herwig, Birgit

    2016-01-01

    Headache is the most common pain disorder in children and adolescents and is associated with diverse dysfunctions and psychological symptoms. Several studies evidenced sex-specific differences in headache frequency. Until now no study exists that examined sex-specific patterns of change in paediatric headache across time and included pain-related somatic and (socio-)psychological predictors. Latent Class Growth Analysis (LCGA) was used in order to identify different trajectory classes of headache across four annual time points in a population-based sample (n = 3 227; mean age 11.34 years; 51.2 % girls). In multinomial logistic regression analyses the influence of several predictors on the class membership was examined. For girls, a four-class model was identified as the best fitting model. While the majority of girls reported no (30.5 %) or moderate headache frequencies (32.5 %) across time, one class with a high level of headache days (20.8 %) and a class with an increasing headache frequency across time (16.2 %) were identified. For boys a two class model with a 'no headache class' (48.6 %) and 'moderate headache class' (51.4 %) showed the best model fit. Regarding logistic regression analyses, migraine and parental headache proved to be stable predictors across sexes. Depression/anxiety was a significant predictor for all pain classes in girls. Life events, dysfunctional stress coping and school burden were also able to differentiate at least between some classes in both sexes. The identified trajectories reflect sex-specific differences in paediatric headache, as seen in the number and type of classes extracted. The documented risk factors can deliver ideas for preventive actions and considerations for treatment programmes.

  11. Sex-specific mechanism of social hierarchy in mice.

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    van den Berg, Wouter E; Lamballais, Sander; Kushner, Steven A

    2015-05-01

    The establishment of social hierarchies is a naturally occurring, evolutionarily conserved phenomenon with a well-established impact on fitness and health. Investigations of complex social group dynamics may offer novel opportunities for translational studies of autism spectrum disorder. Here we describe a robust behavioral paradigm using an automated version of the tube test. Isogenic groups of male and female mice establish linear social hierarchies that remain highly stable for at least 14 days, the longest interval tested. Remarkably, however, their social strategy is sex-specific: females primarily utilize intrinsic attributes, whereas males are strongly influenced by prior social experience. Using both genetic and pharmacological manipulations, we identify testosterone as a critical sex-specific factor for determining which social strategy is used. Males inheriting a null mutation of the sex-determining region Y (Sry) gene used a similar social cognitive strategy as females. In contrast, females with transgenic expression of Sry utilized a typically male social strategy. Analogously, castration of males and testosterone supplementation of females yielded similar outcomes, with a reversal of their social cognitive strategy. Together, our results demonstrate a sex-specific mechanism underlying social hierarchy, in which both males and females retain the functional capacity to adapt their social strategy. More generally, we expect the automated tube test to provide an important complementary approach for both fundamental and translational studies of social behavior.

  12. Long-term fitness benefits of egg sex modification by the Seychelles warbler

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    Komdeur, J

    Sex-ratio theory states that if the fitness costs to the parents of producing one offspring's sex relative to the other are higher, parents should discount these costs by producing fewer individuals of the more costly sex. In the co-operatively breeding Seychelles warbler (Acrocephalus sechellensis)

  13. Fitness prospects: effects of age, sex and recruitment age on reproductive value in a long-lived seabird.

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    Zhang, He; Rebke, Maren; Becker, Peter H; Bouwhuis, Sandra

    2015-01-01

    Reproductive value is an integrated measure of survival and reproduction fundamental to understanding life-history evolution and population dynamics, but little is known about intraspecific variation in reproductive value and factors explaining such variation, if any. By applying generalized additive mixed models to longitudinal individual-based data of the common tern Sterna hirundo, we estimated age-specific annual survival probability, breeding probability and reproductive performance, based on which we calculated age-specific reproductive values. We investigated effects of sex and recruitment age (RA) on each trait. We found age effects on all traits, with survival and breeding probability declining with age, while reproductive performance first improved with age before levelling off. We only found a very small, marginally significant, sex effect on survival probability, but evidence for decreasing age-specific breeding probability and reproductive performance with RA. As a result, males had slightly lower age-specific reproductive values than females, while birds of both sexes that recruited at the earliest ages of 2 and 3 years (i.e. 54% of the tern population) had somewhat higher fitness prospects than birds recruiting at later ages. While the RA effects on breeding probability and reproductive performance were statistically significant, these effects were not large enough to translate to significant effects on reproductive value. Age-specific reproductive values provided evidence for senescence, which came with fitness costs in a range of 17-21% for the sex-RA groups. Our study suggests that intraspecific variation in reproductive value may exist, but that, in the common tern, the differences are small. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

  14. Sex differences in the return-to-work process of cancer survivors 2 years after diagnosis: results from a large French population-based sample.

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    Marino, Patricia; Teyssier, Luis Sagaon; Malavolti, Laetitia; Le Corroller-Soriano, Anne-Gaelle

    2013-04-01

    To investigate the effects of clinical, sociodemographic, and occupational factors on time to return to work (RTW) during the 2 years after cancer diagnosis and to analyze whether sex differences exist. This study was based on a French national cross-sectional survey involving 4,270 cancer survivors. Time to RTW was estimated through the duration of sick leave of 801 cancer survivors younger than 58 years who were employed during the 2-year survey. Multivariate analysis of the RTW after sick leave was performed using a Weibull accelerated failure time model. We found some sex differences in the RTW process. Older men returned to work more slowly than older women (P = .013), whereas married men returned to work much faster than married women (P = .019). Duration dependence was also sex-specific. In men, the time spent on sick leave was independent of the probability of returning to work, whereas in women, this duration dependence was positive (P work contract (P = .042). The factor found to accelerate RTW was a higher educational level (P = .014). The RTW process 2 years after cancer diagnosis differed between men and women. A better knowledge of this process should help the national implementation of more cost-effective strategies for managing the RTW of cancer survivors.

  15. Sex-specific patterns in abundance, temporary emigration and survival of Indo-Pacific bottlenose dolphins (Tursiops aduncus in coastal and estuarine waters

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    Kate R Sprogis

    2016-02-01

    Full Text Available Inherent difficulties in determining the sex of free-ranging sexually monomorphic species often prevents a sex-specific focus on estimating abundance, movement patterns and survival rates. This study provides insights into sex-specific population parameters of Indo-Pacific bottlenose dolphins (Tursiops aduncus. Systematic, boat-based photo-identification surveys (n = 417 were conducted year-round from 2007-2013 in coastal and estuarine waters off Bunbury, Western Australia. Pollock’s Robust Design was used to quantify population parameters for three datasets: i adults and juveniles combined, ii adult females and iii adult males. For all datasets, abundance estimates varied seasonally, with general highs during summer and/or autumn, and lows during winter. Dolphins had seasonally structured temporary emigration rates with similar trends between sexes. The derived return rate (1-γ’ of temporary emigrants into the study area was highest from winter to spring, indicating that dolphins had a high probability of return into the study area during spring. We suggest that the return of dolphins into the study area and increase in abundance is influenced by the breeding season (summer/autumn. Prey availability is likely a main driver responsible for the movement of dolphins out of the study area during winter. Seasonal apparent survival rates were constant and high (0.98-0.99 for all datasets. High apparent survival rates suggest there is no permanent emigration from the study area. Our sex-specific modeling approach offers a comprehensive interpretation of the population dynamics of a top predator in a coastal and estuarine environment and acts as a model for future sex-based population studies on sexually monomorphic species.

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

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    Gamble, Tony

    2016-05-01

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

  17. Experiences of condom fit and feel among African-American men who have sex with men.

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    Reece, Michael; Dodge, Brian; Herbenick, Debby; Fisher, Christopher; Alexander, Andreia; Satinsky, Sonya

    2007-10-01

    To offer an empirical understanding of characteristics associated with the fit and feel of condoms among African-American men who have sex with men (MSM), a particularly high-risk group for HIV and other sexually transmitted infections (STI) in the United States. Survey data were collected from 178 adult African-American MSM attending a community event in Atlanta, Georgia. Although the majority of participants reported that condoms generally fit properly and felt comfortable, a substantial number of men reported a variety of problems with the fit and feel of condoms. Specifically, 21% reported that condoms felt too tight, 18% reported that condoms felt too short, 10% reported that condoms felt too loose, and 7% reported that condoms felt too long. There were significant associations between men's reports of condom breakage and slippage, and their perceptions of condom fit and feel. Perceptions of condom fit and feel were also related to men's reports of seeking condoms for their size-specific properties. The fit and feel issues that men in this sample identified may be among those that contribute to their likelihood of using, or not using, condoms consistently and correctly. A better understanding of these factors will be beneficial to both condom manufacturers and sexual health professionals who share a common goal of increasing consistent and correct condom use and reducing the incidence of HIV and other STI among this and other communities.

  18. The effect of sex on the mean and variance of fitness in facultatively sexual rotifers.

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    Becks, L; Agrawal, A F

    2011-03-01

    The evolution of sex is a classic problem in evolutionary biology. While this topic has been the focus of much theoretical work, there is a serious dearth of empirical data. A simple yet fundamental question is how sex affects the mean and variance in fitness. Despite its importance to the theory, this type of data is available for only a handful of taxa. Here, we report two experiments in which we measure the effect of sex on the mean and variance in fitness in the monogonont rotifer, Brachionus calyciflorus. Compared to asexually derived offspring, we find that sexual offspring have lower mean fitness and less genetic variance in fitness. These results indicate that, at least in the laboratory, there are both short- and long-term disadvantages associated with sexual reproduction. We briefly review the other available data and highlight the need for future work. © 2010 The Authors. Journal of Evolutionary Biology © 2010 European Society For Evolutionary Biology.

  19. The canonical equation of adaptive dynamics for life histories: from fitness-returns to selection gradients and Pontryagin's maximum principle.

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    Metz, Johan A Jacob; Staňková, Kateřina; Johansson, Jacob

    2016-03-01

    This paper should be read as addendum to Dieckmann et al. (J Theor Biol 241:370-389, 2006) and Parvinen et al. (J Math Biol 67: 509-533, 2013). Our goal is, using little more than high-school calculus, to (1) exhibit the form of the canonical equation of adaptive dynamics for classical life history problems, where the examples in Dieckmann et al. (J Theor Biol 241:370-389, 2006) and Parvinen et al. (J Math Biol 67: 509-533, 2013) are chosen such that they avoid a number of the problems that one gets in this most relevant of applications, (2) derive the fitness gradient occurring in the CE from simple fitness return arguments, (3) show explicitly that setting said fitness gradient equal to zero results in the classical marginal value principle from evolutionary ecology, (4) show that the latter in turn is equivalent to Pontryagin's maximum principle, a well known equivalence that however in the literature is given either ex cathedra or is proven with more advanced tools, (5) connect the classical optimisation arguments of life history theory a little better to real biology (Mendelian populations with separate sexes subject to an environmental feedback loop), (6) make a minor improvement to the form of the CE for the examples in Dieckmann et al. and Parvinen et al.

  20. Evolution of sexes from an ancestral mating-type specification pathway.

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    Sa Geng

    2014-07-01

    Full Text Available Male and female sexes have evolved repeatedly in eukaryotes but the origins of dimorphic sexes and their relationship to mating types in unicellular species are not understood. Volvocine algae include isogamous species such as Chlamydomonas reinhardtii, with two equal-sized mating types, and oogamous multicellular species such as Volvox carteri with sperm-producing males and egg-producing females. Theoretical work predicts genetic linkage of a gamete cell-size regulatory gene(s to an ancestral mating-type locus as a possible step in the evolution of dimorphic gametes, but this idea has not been tested. Here we show that, contrary to predictions, a single conserved mating locus (MT gene in volvocine algae-MID, which encodes a RWP-RK domain transcription factor-evolved from its ancestral role in C. reinhardtii as a mating-type specifier, to become a determinant of sperm and egg development in V. carteri. Transgenic female V. carteri expressing male MID produced functional sperm packets during sexual development. Transgenic male V. carteri with RNA interference (RNAi-mediated knockdowns of VcMID produced functional eggs, or self-fertile hermaphrodites. Post-transcriptional controls were found to regulate cell-type-limited expression and nuclear localization of VcMid protein that restricted its activity to nuclei of developing male germ cells and sperm. Crosses with sex-reversed strains uncoupled sex determination from sex chromosome identity and revealed gender-specific roles for male and female mating locus genes in sexual development, gamete fitness and reproductive success. Our data show genetic continuity between the mating-type specification and sex determination pathways of volvocine algae, and reveal evidence for gender-specific adaptations in the male and female mating locus haplotypes of Volvox. These findings will enable a deeper understanding of how a master regulator of mating-type determination in an ancestral unicellular species was

  1. Does the silver moss Bryum argenteum exhibit sex-specific patterns in vegetative growth rate, asexual fitness or prezygotic reproductive investment?

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    Horsley, Kimberly; Stark, Lloyd R; McLetchie, D Nicholas

    2011-05-01

    Expected life history trade-offs associated with sex differences in reproductive investment are often undetected in seed plants, with the difficulty arising from logistical issues of conducting controlled experiments. By controlling genotype, age and resource status of individuals, a bryophyte was assessed for sex-specific and location-specific patterns of vegetative, asexual and sexual growth/reproduction across a regional scale. Twelve genotypes (six male, six female) of the dioecious bryophyte Bryum argenteum were subcultured to remove environmental effects, regenerated asexually to replicate each genotype 16 times, and grown over a period of 92 d. Plants were assessed for growth rates, asexual and sexual reproductive traits, and allocation to above- and below-ground regenerative biomass. The degree of sexual versus asexual reproductive investment appears to be under genetic control, with three distinct ecotypes found in this study. Protonemal growth rate was positively correlated with asexual reproduction and sexual reproduction, whereas asexual reproduction was negatively correlated (appeared to trade-off) with vegetative growth (shoot production). No sex-specific trade-offs were detected. Female sex-expressing shoots were longer than males, but the sexes did not differ in growth traits, asexual traits, sexual induction times, or above- and below-ground biomass. Males, however, had much higher rates of inflorescence production than females, which translated into a significantly higher (24x) prezygotic investment for males relative to females. Evidence for three distinct ecotypes is presented for a bryophyte based on regeneration traits. Prior to zygote production, the sexes of this bryophyte did not differ in vegetative growth traits but significantly differed in reproductive investment, with the latter differences potentially implicated in the strongly biased female sex ratio. The disparity between males and females for prezygotic reproductive investment is

  2. Can Neglected Tropical Diseases Compromise Human Wellbeing in Sex-, Age-, and Trait-Specific Ways?

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    David C Geary

    2016-04-01

    Full Text Available Traits that facilitate competition for reproductive resources or that influence mate choice have evolved to signal resilience to infectious disease and other stressors. As a result, the dynamics of competition and choice can, in theory, be used to generate predictions about sex-, age-, and trait-specific vulnerabilities for any sexually reproducing species, including humans. These dynamics and associated vulnerabilities are reviewed for nonhuman species, focusing on traits that are compromised by exposure to parasites. Using the same approach, sex-, age-, and trait-specific vulnerabilities to parasitic disease are illustrated for children's and adolescent's physical growth and fitness. Suggestions are then provided for widening the assessment of human vulnerabilities to include age-appropriate measures of behavioral (e.g., children's play and cognitive (e.g., language fluency traits. These are traits that are likely to be compromised by infection in age- and sex-specific ways. Inclusion of these types of measures in studies of neglected tropic diseases has the potential to provide a more nuanced understanding of how these diseases undermine human wellbeing and may provide a useful means to study the efficacy of associated treatments.

  3. Effects of seed size, inbreeding and maternal sex on offspring fitness in gynodioecious Plantago coronopus

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    Koelewijn, H.P.; Damme, van J.M.M.

    2005-01-01

    1 Male steriles (MS) must have a fitness advantage relative to hermaphrodites (H) if they are to be maintained in gynodioecious species. We report experiments in which we disentangle the relative contributions of seed size, inbreeding and maternal sex to the fitness advantage of male steriles in

  4. Sex Differences in Time to Return-to-Play Progression After Sport-Related Concussion.

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    Stone, Sarah; Lee, Bobby; Garrison, J Craig; Blueitt, Damond; Creed, Kalyssa

    2016-10-03

    Recently, female sports participation has increased, and there is a tendency for women to experience more symptoms and variable presentation after sport-related concussion (SRC). The purpose of this study was to determine whether sex differences exist in time to begin a return-to-play (RTP) progression after an initial SRC. After initial SRC, female athletes (11-20 years old) would take longer to begin an RTP progression compared with age-matched male athletes. Retrospective cohort study. Level 3. A total of 579 participants (365 males [mean age, 15.0 ± 1.7 years], 214 females [mean age, 15.2 ± 1.5 years]), including middle school, high school, and collegiate athletes who participated in various sports and experienced an initial SRC were included and underwent retrospective chart review. The following information was collected: sex, age at injury, sport, history of prior concussion, date of injury, and date of initiation of RTP progression. Participants with a history of more than 1 concussion or injury sustained from non-sport-related activity were excluded. Despite American football having the greatest percentage (49.2%) of sport participation, female athletes took significantly longer to start an RTP progression after an initial SRC (29.1 ± 26.3 days) compared with age-matched male athletes (22.7 ± 18.3 days; P = 0.002). On average, female athletes took approximately 6 days longer to begin an RTP progression compared with age-matched male athletes. This suggests that sex differences exist between athletes, ages 11 to 20 years, with regard to initiation of an RTP progression after SRC. Female athletes may take longer to recover after an SRC, and therefore, may take longer to return to sport. Sex should be considered as part of the clinical decision-making process when determining plan of care for this population. © 2016 The Author(s).

  5. Returns to Tenure, Firm-Specific Human Capital and Worker Heterogeneity

    DEFF Research Database (Denmark)

    Bingley, Paul; Westergård-Nielsen, Niels Chr.

    2003-01-01

    Workers with longer job tenure are paid more, on average, than those with shorter tenure. This paper re-opens the debate about whether individual financial returns to tenure are due to firm-specific human capital accumulation or sorting according to unobserved individual productivity heterogeneity...... firms to distinguish between firm-specific human capital and worker heterogeneity. Although the proportion of tenure returns due to firm-specific human capital is smaller than that found in the US, it has increased from 10% in 1980 to 30% in 1998 in Denmark. This change coincides with decentralisation...

  6. Returnable packaging for non-specific building materials

    NARCIS (Netherlands)

    Gassel, van F.J.M.

    1998-01-01

    A certain amount of construction waste comes from disposable packaging and this waste is ecologically damaging, one solution would be to reduce the disposable by using returnable packaging for non-specific construction products. To find out if this solution is feasible a study has been carried out

  7. Kinetics of concentration decay of specific organic matter in UASB reactors operating with and without return of aerobic sludge.

    Science.gov (United States)

    Pontes, P P; Chernicharo, C A L; Von Sperling, M

    2014-08-01

    This study aimed at assessing the influence of the return of excess aerobic sludge from a trickling filter (TF) upon the anaerobic digestion process in an upflow anaerobic sludge blanket (UASB) reactor, by evaluating its effect on the kinetics of the decay of specific organic matter (carbohydrates, proteins and lipids), as well as on the concentrations of volatile fatty acids in the UASB reactor. A pilot-scale UASB/TF system was used to perform the experiments, operating with (phase 2) and without (phase 1) excess sludge return from the TF to the UASB reactor. Sampling was carried out at different heights of the UASB reactor (0, 25, 125 and 225-cm height), and profile concentrations were determined for the following parameters: carbohydrates, proteins, lipids and volatile fatty acids. First-order kinetics showed the best fit to the decay of concentrations of carbohydrates, proteins, lipids and chemical oxygen demand (COD) in the UASB reactor. The parameters showing the best fit to the first-order kinetics were proteins and COD, during the sludge return phase. The occurrence of higher apparent reaction constants was further observed during the sludge return phase. For an influent COD concentration of 600 mg L-1 and hydraulic retention times of 2.1, 2.6 and 3.0 h in phase 1, the effluent COD concentrations were 125.3, 88.4 and 62.4 mg L-1, respectively, whereas in phase 2, the effluent COD concentrations were 75.5, 47.6 and 30.1 mg L-1, respectively.

  8. Autologous osteochondral mosaicplasty or TruFit plugs for cartilage repair.

    Science.gov (United States)

    Hindle, Paul; Hendry, Jane L; Keating, John F; Biant, Leela C

    2014-06-01

    Autologous osteochondral mosaicplasty and TruFit Bone graft substitute plugs are methods used to repair symptomatic articular cartilage defects in the adult knee. There have been no comparative studies of the two techniques. This retrospective study assessed functional outcome of patients using the EQ-5D, Knee Injury and Osteoarthritis Outcome Score (KOOS) and Modified Cincinnati scores at follow-up of 1-5 years. There were 66 patients in the study (35 TruFit and 31 Mosaicplasty): 44 males and 22 females with a mean age of 37.3 years (SD 12.6). The mean BMI was 26.8. Thirty-six articular cartilage lesions were due to trauma, twenty-six due to osteochondritis dissecans and three due to non-specific degenerative change or unknown. There was no difference between the two groups age (n.s.), sex (n.s.), BMI (n.s.), defect location (n.s.) or aetiology (n.s.). The median follow-up was 22 months for the TruFit cohort and 30 months for the mosaicplasty group. There was no significant difference in the requirement for re-operation (n.s). Patients undergoing autologous mosaicplasty had a higher rate of returning to sport (p = 0.006), lower EQ-5D pain scores (p = 0.048) and higher KOOS activities of daily living (p = 0.029) scores. Sub-group analysis showed no difference related to the number of cases the surgeon performed. Patients requiring re-operation had lower outcome scores regardless of their initial procedure. This study demonstrated significantly better outcomes using two validated outcome scores (KOOS, EQ-5D), and an ability to return to sport in those undergoing autologous mosaicplasty compared to those receiving TruFit plugs. IV.

  9. Conservation and sex-specific splicing of the doublesex gene

    Indian Academy of Sciences (India)

    Genetic control of sex determination in insects has been best characterized in Drosophila melanogaster, where the master gene Sxl codes for RNA that is sex specifically spliced to produce a functional protein only in females. SXL regulates the sex-specific splicing of transformer (tra) RNA which, in turn, regulates the ...

  10. Sex-specific life history responses to nymphal diet quality and immune status in a field cricket.

    Science.gov (United States)

    Kelly, C D; Neyer, A A; Gress, B E

    2014-02-01

    Individual fitness is expected to benefit from earlier maturation at a larger body size and higher body condition. However, poor nutritional quality or high prevalence of disease make this difficult because individuals either cannot acquire sufficient resources or must divert resources to other fitness-related traits such as immunity. Under such conditions, individuals are expected to mature later at a smaller body size and in poorer body condition. Moreover, the juvenile environment can also produce longer-term effects on adult fitness by causing shifts in resource allocation strategies that could alter investment in immune function and affect adult lifespan. We manipulated diet quality and immune status of juvenile Texas field crickets, Gryllus texensis, to investigate how poor developmental conditions affect sex-specific investment in fitness-related traits. As predicted, a poor juvenile diet was related to smaller mass and body size at eclosion in both sexes. However, our results also reveal sexually dimorphic responses to different facets of the rearing environment: female life history decisions are affected more by diet quality, whereas males are affected more by immune status. We suggest that females respond to decreased nutritional income because this threatens their ability to achieve a large adult body size, whereas male fitness is more dependent on reaching adulthood and so they invest in immunity and survival to eclosion. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

  11. Do sex-specific densities affect local survival of free-ranging great tits?

    NARCIS (Netherlands)

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

    2011-01-01

    Competition within sexes is expected when resources are sex specific, whereas competition between sexes can occur when similar resources are exploited. Local population density and sex ratio will determine the amount of sex-specific interactions and thus the potential degree of sex-specific

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

    DEFF Research Database (Denmark)

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

    2015-01-01

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

  13. Sex-specific mechanisms for responding to stress.

    Science.gov (United States)

    Bangasser, Debra A; Wicks, Brittany

    2017-01-02

    Posttraumatic stress disorder and major depression share stress as an etiological contributor and are more common in women than in men. Traditionally, preclinical studies investigating the neurobiological underpinnings of stress vulnerability have used only male rodents; however, recent studies that include females are finding sex-specific mechanisms for responding to stress. This Mini-Review examines recent literature using a framework developed by McCarthy and colleagues (2012; J Neurosci 32:2241-2247) that highlights different types of sex differences. First, we detail how learned fear responses in rats are sexually dimorphic. Then, we contrast this finding with fear extinction, which is similar in males and females at the behavioral level but at the circuitry level is associated with sex-specific cellular changes and, thus, exemplifies a sex convergence. Next, sex differences in stress hormones are detailed. Finally, the effects of stress on learning, attention, and arousal are used to highlight the concept of a sex divergence in which the behavior of males and females is similar at baseline but diverges following stressor exposure. We argue that appreciating and investigating the diversity of sex differences in stress response systems will improve our understanding of vulnerability and resilience to stress-related psychiatric disorders and likely lead to the development of novel therapeutics for better treatment of these disorders in both men and women. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  14. Maternal provision of non-sex-specific transformer messenger RNA in sex determination of the wasp Asobara tabida.

    Science.gov (United States)

    Geuverink, E; Verhulst, E C; van Leussen, M; van de Zande, L; Beukeboom, L W

    2018-02-01

    In many insect species maternal provision of sex-specifically spliced messenger RNA (mRNA) of sex determination genes is an essential component of the sex determination mechanism. In haplodiploid Hymenoptera, maternal provision in combination with genomic imprinting has been shown for the parasitoid Nasonia vitripennis, known as maternal effect genomic imprinting sex determination (MEGISD). Here, we characterize the sex determination cascade of Asobara tabida, another hymenopteran parasitoid. We show the presence of the conserved sex determination genes doublesex (dsx), transformer (tra) and transformer-2 (tra2) orthologues in As. tabida. Of these, At-dsx and At-tra are sex-specifically spliced, indicating a conserved function in sex determination. At-tra and At-tra2 mRNA is maternally provided to embryos but, in contrast to most studied insects, As. tabida females transmit a non-sex-specific splice form of At-tra mRNA to the eggs. In this respect, As. tabida sex determination differs from the MEGISD mechanism. How the paternal genome can induce female development in the absence of maternal provision of sex-specifically spliced mRNA remains an open question. Our study reports a hitherto unknown variant of maternal effect sex determination and accentuates the diversity of insect sex determination mechanisms. © 2017 The Authors. Insect Molecular Biology published by John Wiley & Sons Ltd on behalf of Royal Entomological Society.

  15. Reference Curves for Field Tests of Musculoskeletal Fitness in U.S. Children and Adolescents: The 2012 NHANES National Youth Fitness Survey.

    Science.gov (United States)

    Laurson, Kelly R; Saint-Maurice, Pedro F; Welk, Gregory J; Eisenmann, Joey C

    2017-08-01

    Laurson, KR, Saint-Maurice, PF, Welk, GJ, and Eisenmann, JC. Reference curves for field tests of musculoskeletal fitness in U.S. children and adolescents: The 2012 NHANES National Youth Fitness Survey. J Strength Cond Res 31(8): 2075-2082, 2017-The purpose of the study was to describe current levels of musculoskeletal fitness (MSF) in U.S. youth by creating nationally representative age-specific and sex-specific growth curves for handgrip strength (including relative and allometrically scaled handgrip), modified pull-ups, and the plank test. Participants in the National Youth Fitness Survey (n = 1,453) were tested on MSF, aerobic capacity (via submaximal treadmill test), and body composition (body mass index [BMI], waist circumference, and skinfolds). Using LMS regression, age-specific and sex-specific smoothed percentile curves of MSF were created and existing percentiles were used to assign age-specific and sex-specific z-scores for aerobic capacity and body composition. Correlation matrices were created to assess the relationships between z-scores on MSF, aerobic capacity, and body composition. At younger ages (3-10 years), boys scored higher than girls for handgrip strength and modified pull-ups, but not for the plank. By ages 13-15, differences between the boys and girls curves were more pronounced, with boys scoring higher on all tests. Correlations between tests of MSF and aerobic capacity were positive and low-to-moderate in strength. Correlations between tests of MSF and body composition were negative, excluding absolute handgrip strength, which was inversely related to other MSF tests and aerobic capacity but positively associated with body composition. The growth curves herein can be used as normative reference values or a starting point for creating health-related criterion reference standards for these tests. Comparisons with prior national surveys of physical fitness indicate that some components of MSF have likely decreased in the United States over

  16. Density-dependent sex ratio and sex-specific preference for host traits in parasitic bat flies.

    Science.gov (United States)

    Szentiványi, Tamara; Vincze, Orsolya; Estók, Péter

    2017-08-29

    Deviation of sex ratios from unity in wild animal populations has recently been demonstrated to be far more prevalent than previously thought. Ectoparasites are prominent examples of this bias, given that their sex ratios vary from strongly female- to strongly male-biased both among hosts and at the metapopulation level. To date our knowledge is very limited on how and why these biased sex ratios develop. It was suggested that sex ratio and sex-specific aggregation of ectoparasites might be shaped by the ecology, behaviour and physiology of both hosts and their parasites. Here we investigate a highly specialised, hematophagous bat fly species with strong potential to move between hosts, arguably limited inbreeding effects, off-host developmental stages and extended parental care. We collected a total of 796 Nycteribia kolenatii bat flies from 147 individual bats using fumigation and subsequently determined their sex. We report a balanced sex ratio at the metapopulation level and a highly variable sex ratio among infrapopulations ranging from 100% male to 100% female. We show that infrapopulation sex ratio is not random and is highly correlated with infrapopulation size. Sex ratio is highly male biased in small and highly female biased in large infrapopulations. We show that this pattern is most probably the result of sex-specific preference in bat flies for host traits, most likely combined with a higher mobility of males. We demonstrate that female bat flies exert a strong preference for high host body condition and female hosts, while the distribution of males is more even. Our results suggest that locally biased sex ratios can develop due to sex-specific habitat preference of parasites. Moreover, it is apparent that the sex of both hosts and parasites need to be accounted for when a better understanding of host-parasite systems is targeted.

  17. Sex-Specificity in the Reward Value of Facial Attractiveness.

    Science.gov (United States)

    Hahn, Amanda C; Fisher, Claire I; DeBruine, Lisa M; Jones, Benedict C

    2016-05-01

    Studies of the sex-specificity of sexual arousal in adults (i.e., the tendency to respond more strongly to preferred-sex individuals than non-preferred sex individuals) have suggested that heterosexual men, homosexual men, and homosexual women show stronger sex-specific responses than do heterosexual women. Evidence for a similar pattern of results in studies investigating the reward value of faces is equivocal. Consequently, we investigated the effects of (1) sexual orientation (homosexual vs. heterosexual), (2) sex (male vs. female), (3) image sex (preferred-sex vs. non-preferred-sex), and (4) the physical attractiveness of the individual shown in the image on the reward value of faces. Participants were 130 heterosexual men, 130 homosexual men, 130 heterosexual women, and 130 homosexual women. The reward value of faces was assessed using a standard key-press task. Multilevel modeling of responses indicated that images of preferred-sex individuals were more rewarding than images of non-preferred-sex individuals and that this preferred-sex bias was particularly pronounced when more physically attractive faces were presented. These effects were not qualified by interactions involving either the sexual orientation or the sex of our participants, however, suggesting that the preferred-sex bias in the reward value of faces is similar in heterosexual men, homosexual men, heterosexual women, and homosexual women.

  18. Sex-specific lifespan and its evolution in nematodes.

    Science.gov (United States)

    Ancell, Henry; Pires-daSilva, Andre

    2017-10-01

    Differences between sexes of the same species in lifespan and aging rate are widespread. While the proximal and evolutionary causes of aging are well researched, the factors that contribute to sex differences in these traits have been less studied. The striking diversity of nematodes provides ample opportunity to study variation in sex-specific lifespan patterns associated with shifts in life history and mating strategy. Although the plasticity of these sex differences will make it challenging to generalize from invertebrate to vertebrate systems, studies in nematodes have enabled empirical evaluation of predictions regarding the evolution of lifespan. These studies have highlighted how natural and sexual selection can generate divergent patterns of lifespan if the sexes are subject to different rates or sources of mortality, or if trade-offs between complex traits and longevity are resolved differently in each sex. Here, we integrate evidence derived mainly from nematodes that addresses the molecular and evolutionary basis of sex-specific aging and lifespan. Ultimately, we hope to generate a clearer picture of current knowledge in this area, and also highlight the limitations of our understanding. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. Evaluation of starter dietary digestible lysine level on broilers raised under a sex-separated or straight-run housing regime, part 2: Economics of sex separation and digestible lysine level for maximum returns.

    Science.gov (United States)

    Da Costa, M J; Colson, G; Frost, T J; Halley, J; Pesti, G M

    2017-09-01

    The objective of this experiment was to determine the maximum net returns digestible lysine (dLys) levels (MNRL) when maintaining the ideal amino acid ratio for starter diets of broilers raised sex separate or comingled (straight-run). A total of 3,240 Ross 708 chicks was separated by sex and placed in 90 pens by 2 rearing types: sex separate (36 males or 36 females) or straight-run (18 males + 18 females). Each rearing type was fed 6 starter diets (25 d) formulated to have dLys levels between 1.05 and 1.80%. A common grower diet with 1.02% of dLys was fed from 25 to 32 days. Body weight gain (BWG) and feed intake were assessed at 25 and 32 d for performance evaluation. Additionally, at 26 and 33 d, 4 birds per pen were sampled for carcass yield evaluation. Data were modeled using response surface methodology in order to estimate feed intake and whole carcass weight at 1,600 g live BW. Returns over feed cost were estimated for a 1.8-million-broiler complex of each rearing system under 9 feed/meat price scenarios. Results indicated that females needed more feed to reach market weight, followed by straight-run birds, and then males. At medium meat and feed prices, female birds had MNRL at 1.07% dLys, whereas straight-run and males had MNRL at 1.05%. As feed and meat prices increased, females had MNRL increased up to 1.15% dLys. Sex separation resulted in increased revenue under certain feed and meat prices, and before sex separation cost was deducted. When the sexing cost was subtracted from the returns, sex separation was not shown to be economically viable when targeting birds for light market BW. © 2017 Poultry Science Association Inc.

  20. Sex-Specific Neurotoxic Effects of Organophosphate Pesticides Across the Life Course.

    Science.gov (United States)

    Comfort, Nicole; Re, Diane B

    2017-12-01

    This review discusses the sex-specific effects of exposure to various organophosphate (OP) pesticides throughout the life course and potential reasons for the differential vulnerabilities observed across sexes. Sex is a crucial factor in the response to toxicants, yet the sex-specific effects of OP exposure, particularly in juveniles and adults, remain unresolved. This is largely due to study design and inconsistencies in exposure and outcome assessments. Exposure to OPs results in multiple adverse outcomes influenced by many factors including sex. Reported sex-specific effects suggest that males are more susceptible to OPs, which reflects the sex-dependent prevalence of various neurodevelopmental and neurodegenerative disorders such as autism and amyotrophic lateral sclerosis (ALS), in which males are at greater risk. Thus, this review proposes that the biological sex-specific effects elicited by OP exposure may in part underlie the dimorphic susceptibilities observed in neurological disorders. Understanding the immediate and long-term effects of OP exposure across sexes will be critical in advancing our understanding of OP-induced neurotoxicity and disease.

  1. Facial Resemblance Exaggerates Sex-Specific Jealousy-Based Decisions1

    Directory of Open Access Journals (Sweden)

    Steven M. Platek

    2007-01-01

    Full Text Available Sex differences in reaction to a romantic partner's infidelity are well documented and are hypothesized to be attributable to sex-specific jealousy mechanisms which are utilized to solve adaptive problems associated with risk of extra-pair copulation. Males, because of the risk of cuckoldry become more upset by sexual infidelity, while females, because of loss of resources and biparental investment tend to become more distressed by emotional infidelity. However, the degree to which these sex-specific reactions to jealousy interact with cues to kin are completely unknown. Here we investigated the interaction of facial resemblance with decisions about sex-specific jealousy scenarios. Fifty nine volunteers were asked to imagine that two different people (represented by facial composites informed them about their romantic partner's sexual or emotional infidelity. Consistent with previous research, males ranked sexual infidelity scenarios as most upsetting and females ranked emotional infidelity scenarios most upsetting. However, when information about the infidelity was provided by a face that resembled the subject, sex-specific reactions to jealousy were exaggerated. This finding highlights the use of facial resemblance as a putative self-referent phenotypic matching cue that impacts trusting behavior in sexual contexts.

  2. The Mitochondrial Lon Protease Is Required for Age-Specific and Sex-Specific Adaptation to Oxidative Stress.

    Science.gov (United States)

    Pomatto, Laura C D; Carney, Caroline; Shen, Brenda; Wong, Sarah; Halaszynski, Kelly; Salomon, Matthew P; Davies, Kelvin J A; Tower, John

    2017-01-09

    Multiple human diseases involving chronic oxidative stress show a significant sex bias, including neurodegenerative diseases, cancer, immune dysfunction, diabetes, and cardiovascular disease. However, a possible molecular mechanism for the sex bias in physiological adaptation to oxidative stress remains unclear. Here, we report that Drosophila melanogaster females but not males adapt to hydrogen peroxide stress, whereas males but not females adapt to paraquat (superoxide) stress. Stress adaptation in each sex requires the conserved mitochondrial Lon protease and is associated with sex-specific expression of Lon protein isoforms and proteolytic activity. Adaptation to oxidative stress is lost with age in both sexes. Transgenic expression of transformer gene during development transforms chromosomal males into pseudo-females and confers the female-specific pattern of Lon isoform expression, Lon proteolytic activity induction, and H 2 O 2 stress adaptation; these effects were also observed using adult-specific transformation. Conversely, knockdown of transformer in chromosomal females eliminates the female-specific Lon isoform expression, Lon proteolytic activity induction, and H 2 O 2 stress adaptation and produces the male-specific paraquat (superoxide) stress adaptation. Sex-specific expression of alternative Lon isoforms was also observed in mouse tissues. The results develop Drosophila melanogaster as a model for sex-specific stress adaptation regulated by the Lon protease, with potential implications for understanding sexual dimorphism in human disease. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. alpha AD alpha hybrids of Cryptococcus neoformans: evidence of same-sex mating in nature and hybrid fitness.

    Directory of Open Access Journals (Sweden)

    Xiaorong Lin

    2007-10-01

    Full Text Available Cryptococcus neoformans is a ubiquitous human fungal pathogen that causes meningoencephalitis in predominantly immunocompromised hosts. The fungus is typically haploid, and sexual reproduction involves two individuals with opposite mating types/sexes, alpha and a. However, the overwhelming predominance of mating type (MAT alpha over a in C. neoformans populations limits alpha-a mating in nature. Recently it was discovered that C. neoformans can undergo same-sex mating under laboratory conditions, especially between alpha isolates. Whether same-sex mating occurs in nature and contributes to the current population structure was unknown. In this study, natural alpha AD alpha hybrids that arose by fusion between two alpha cells of different serotypes (A and D were identified and characterized, providing definitive evidence that same-sex mating occurs naturally. A novel truncated allele of the mating-type-specific cell identity determinant SXI1 alpha was also identified as a genetic factor likely involved in this process. In addition, laboratory-constructed alpha AD alpha strains exhibited hybrid vigor both in vitro and in vivo, providing a plausible explanation for their relative abundance in nature despite the fact that AD hybrids are inefficient in meiosis/sporulation and are trapped in the diploid state. These findings provide insights on the origins, genetic mechanisms, and fitness impact of unisexual hybridization in the Cryptococcus population.

  4. Species- and sex-specific connectivity effects of habitat fragmentation in a suite of woodland birds.

    Science.gov (United States)

    Amos, Nevil; Harrisson, Katherine A; Radford, James Q; White, Matt; Newell, Graeme; Mac Nally, Ralph; Sunnucks, Paul; Pavlova, Alexandra

    2014-06-01

    Loss of functional connectivity following habitat loss and fragmentation could drive species declines. A comprehensive understanding of fragmentation effects on functional connectivity of an ecological assemblage requires investigation of multiple species with different mobilities, at different spatial scales, for each sex, and in different landscapes. Based on published data on mobility and ecological responses to fragmentation of 10 woodland-dependent birds, and using simulation studies, we predicted that (1) fragmentation would impede dispersal and gene flow of eight "decliners" (species that disappear from suitable patches when landscape-level tree cover falls below species-specific thresholds), but not of two "tolerant" species (whose occurrence in suitable habitat patches is independent of landscape tree cover); and that fragmentation effects would be stronger (2) in the least mobile species, (3) in the more philopatric sex, and (4) in the more fragmented region. We tested these predictions by evaluating spatially explicit isolation-by-landscape-resistance models of gene flow in fragmented landscapes across a 50 x 170 km study area in central Victoria, Australia, using individual and population genetic distances. To account for sex-biased dispersal and potential scale- and configuration-specific effects, we fitted models specific to sex and geographic zones. As predicted, four of the least mobile decliners showed evidence of reduced genetic connectivity. The responses were strongly sex specific, but in opposite directions in the two most sedentary species. Both tolerant species and (unexpectedly) four of the more mobile decliners showed no reduction in gene flow. This is unlikely to be due to time lags because more mobile species develop genetic signatures of fragmentation faster than do less mobile ones. Weaker genetic effects were observed in the geographic zone with more aggregated vegetation, consistent with gene flow being unimpeded by landscape

  5. Who Has the Advantage? Race and Sex Differences in Returns to Social Capital at Home and at School*

    Science.gov (United States)

    Dufur, Mikaela J.; Parcel, Toby L.; Hoffmann, John P.; Braudt, David B.

    2016-01-01

    A growing body of literature suggests that social capital is a valuable resource for children and youth, and that returns to that capital can increase academic success. However, relatively little is known about whether youth from different backgrounds build social capital in the same way and whether they receive the same returns to that capital. We examine the creation of and returns to social capital in family and school settings on academic achievement, measured as standardized test scores, for white boys, black boys, white girls, and black girls who were seniors in high school in the United States. Our findings suggest that while youth in different groups build social capital in largely the same way, differences exist by race and sex as to how family social capital affects academic achievement. Girls obtain greater returns to family social capital than do boys, but no group receives significant returns to school social capital after controlling for individual- and school-level characteristics. PMID:27594731

  6. Physical Fitness Percentiles of German Children Aged 9-12 Years: Findings from a Longitudinal Study.

    Directory of Open Access Journals (Sweden)

    Kathleen Golle

    Full Text Available Generating percentile values is helpful for the identification of children with specific fitness characteristics (i.e., low or high fitness level to set appropriate fitness goals (i.e., fitness/health promotion and/or long-term youth athlete development. Thus, the aim of this longitudinal study was to assess physical fitness development in healthy children aged 9-12 years and to compute sex- and age-specific percentile values.Two-hundred and forty children (88 girls, 152 boys participated in this study and were tested for their physical fitness. Physical fitness was assessed using the 50-m sprint test (i.e., speed, the 1-kg ball push test, the triple hop test (i.e., upper- and lower- extremity muscular power, the stand-and-reach test (i.e., flexibility, the star run test (i.e., agility, and the 9-min run test (i.e., endurance. Age- and sex-specific percentile values (i.e., P10 to P90 were generated using the Lambda, Mu, and Sigma method. Adjusted (for change in body weight, height, and baseline performance age- and sex-differences as well as the interactions thereof were expressed by calculating effect sizes (Cohen's d.Significant main effects of Age were detected for all physical fitness tests (d = 0.40-1.34, whereas significant main effects of Sex were found for upper-extremity muscular power (d = 0.55, flexibility (d = 0.81, agility (d = 0.44, and endurance (d = 0.32 only. Further, significant Sex by Age interactions were observed for upper-extremity muscular power (d = 0.36, flexibility (d = 0.61, and agility (d = 0.27 in favor of girls. Both, linear and curvilinear shaped curves were found for percentile values across the fitness tests. Accelerated (curvilinear improvements were observed for upper-extremity muscular power (boys: 10-11 yrs; girls: 9-11 yrs, agility (boys: 9-10 yrs; girls: 9-11 yrs, and endurance (boys: 9-10 yrs; girls: 9-10 yrs. Tabulated percentiles for the 9-min run test indicated that running distances between 1

  7. Sex linkage, sex-specific selection, and the role of recombination in the evolution of sexually dimorphic gene expression.

    Science.gov (United States)

    Connallon, Tim; Clark, Andrew G

    2010-12-01

    Sex-biased genes--genes that are differentially expressed within males and females--are nonrandomly distributed across animal genomes, with sex chromosomes and autosomes often carrying markedly different concentrations of male- and female-biased genes. These linkage patterns are often gene- and lineage-dependent, differing between functional genetic categories and between species. Although sex-specific selection is often hypothesized to shape the evolution of sex-linked and autosomal gene content, population genetics theory has yet to account for many of the gene- and lineage-specific idiosyncrasies emerging from the empirical literature. With the goal of improving the connection between evolutionary theory and a rapidly growing body of genome-wide empirical studies, we extend previous population genetics theory of sex-specific selection by developing and analyzing a biologically informed model that incorporates sex linkage, pleiotropy, recombination, and epistasis, factors that are likely to vary between genes and between species. Our results demonstrate that sex-specific selection and sex-specific recombination rates can generate, and are compatible with, the gene- and species-specific linkage patterns reported in the genomics literature. The theory suggests that sexual selection may strongly influence the architectures of animal genomes, as well as the chromosomal distribution of fixed substitutions underlying sexually dimorphic traits. © 2010 The Author(s). Evolution© 2010 The Society for the Study of Evolution.

  8. Physical Fitness Reference Standards in French Youth: The BOUGE Program.

    Science.gov (United States)

    Vanhelst, Jérémy; Labreuche, Julien; Béghin, Laurent; Drumez, Elodie; Fardy, Paul S; Chapelot, Didier; Mikulovic, Jacques; Ulmer, Zékya

    2017-06-01

    The aim of this study was to establish sex- and age-specific physical fitness percentiles in French youth. A sample of 11,186 children and adolescents (5,546 boys and 5,640 girls), aged between 10 and 15 years, was assessed in the French national BOUGE study. Participants were tested for their cardiorespiratory fitness, muscular endurance, speed, flexibility, and agility using the following tests: 20-m shuttle run tests, curl-ups test, 50-m sprint test, back-saver sit and reach test, and 10 × 5-m shuttle run test. Percentile values were estimated for French youth as a function of age stratified by sex using the generalized additive model for location, scale, and shape (GAMLSS). In general, physical fitness was better in boys than in girls, except for the back-saver sit and reach test, in which girls performed better. Except for the back-saver sit and reach test and 10 × 5-m shuttle run test, physical fitness performance was significantly associated with age. Sex- and age-specific normative values for physical fitness tests in French youth expressed as percentiles from the fifth to the 95th are provided. Reference values provide normative data for French youth. The data are useful in identifying special needs for appropriate intervention programs.

  9. Sex-specific evolution during the diversification of live-bearing fishes.

    Science.gov (United States)

    Culumber, Zachary W; Tobler, Michael

    2017-08-01

    Natural selection is often assumed to drive parallel functional diversification of the sexes. But males and females exhibit fundamental differences in their biology, and it remains largely unknown how sex differences affect macroevolutionary patterns. On microevolutionary scales, we understand how natural and sexual selection interact to give rise to sex-specific evolution during phenotypic diversification and speciation. Here we show that ignoring sex-specific patterns of functional trait evolution misrepresents the macroevolutionary adaptive landscape and evolutionary rates for 112 species of live-bearing fishes (Poeciliidae). Males and females of the same species evolve in different adaptive landscapes. Major axes of female morphology were correlated with environmental variables but not reproductive investment, while male morphological variation was primarily associated with sexual selection. Despite the importance of both natural and sexual selection in shaping sex-specific phenotypic diversification, species diversification was overwhelmingly associated with ecological divergence. Hence, the inter-predictability of mechanisms of phenotypic and species diversification may be limited in many systems. These results underscore the importance of explicitly addressing sex-specific diversification in empirical and theoretical frameworks of evolutionary radiations to elucidate the roles of different sources of selection and constraint.

  10. Sex-specific associative learning cues and inclusive fitness benefits in the Seychelles warbler

    NARCIS (Netherlands)

    Richardson, DS; Burke, T; Komdeur, J

    In cooperative, breeding vertebrates, indirect fitness benefits would be maximized by subordinates that accurately assess their relatedness to group offspring and preferentially help more closely related kin. In the Seychelles warbler (Acrocephalus sechellensis), we found a positive relationship

  11. Vasopressin and oxytocin receptor systems in the brain: Sex differences and sex-specific regulation of social behavior.

    Science.gov (United States)

    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.

  12. Vasopressin and oxytocin receptor systems in the brain: sex differences and sex-specific regulation of social behavior

    Science.gov (United States)

    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

  13. Standard specification for beaded process glass pipe and fittings

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2002-01-01

    1.1 This specification covers chemically resistant, low expansion Type-I borosilicate glass, Class A, (see Specification E 438) used to manufacture beaded end flanged-glass pipe and fittings for pressure and vacuum applications.

  14. Contextual modulation of social and endocrine correlates of fitness: insights from the life history of a sex changing fish.

    Science.gov (United States)

    Pradhan, Devaleena S; Solomon-Lane, Tessa K; Grober, Matthew S

    2015-01-01

    Steroid hormones are critical regulators of reproductive life history, and the steroid sensitive traits (morphology, behavior, physiology) associated with particular life history stages can have substantial fitness consequences for an organism. Hormones, behavior and fitness are reciprocally associated and can be used in an integrative fashion to understand how the environment impacts organismal function. To address the fitness component, we highlight the importance of using reliable proxies of reproductive success when studying proximate regulation of reproductive phenotypes. To understand the mechanisms by which the endocrine system regulates phenotype, we discuss the use of particular endocrine proxies and the need for appropriate functional interpretation of each. Lastly, in any experimental paradigm, the responses of animals vary based on the subtle differences in environmental and social context and this must also be considered. We explore these different levels of analyses by focusing on the fascinating life history transitions exhibited by the bi-directionally hermaphroditic fish, Lythrypnus dalli. Sex changing fish are excellent models for providing a deeper understanding of the fitness consequences associated with behavioral and endocrine variation. We close by proposing that local regulation of steroids is one potential mechanism that allows for the expression of novel phenotypes that can be characteristic of specific life history stages. A comparative species approach will facilitate progress in understanding the diversity of mechanisms underlying the contextual regulation of phenotypes and their associated fitness correlates.

  15. Employers' views on the fit note.

    Science.gov (United States)

    Kotze, E

    2014-12-01

    The fit note replaced the sick note in 2010. The statement of fitness for work (fit note) is expected to benefit the British economy by helping more people stay in work and prevent long-term sickness absence. Understanding and responding to employers' views on the fit note is key, in order for this goal to be achieved. To explore employers' views on the fit note. A qualitative study was undertaken and face-to-face interviews were conducted with participants representing employers from a variety of industries. There were 21 participants who were mainly human resources officers and line managers. Employers welcomed the introduction of the fit note and felt that it was an improvement on the sick note. The majority of employers felt the fit note had the potential to promote an earlier return to work, if used properly. The main problems reported were the completion of the fit notes and quality of advice received from general practitioners. Employers felt that the most helpful advice came from fit notes with information on the functional effects of the medical condition. Some employers found return to work decisions problematic. The fit note has the potential to promote an earlier return to work. In order for the fit note to achieve its aim, further understanding of the difficulties employers are having when making return to work decisions is important, in order to develop guidance to enable them to provide the practical support employees need to return to work sooner. © The Author 2014. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Construction of physical maps for the sex-specific regions of papaya sex chromosomes

    Directory of Open Access Journals (Sweden)

    Na Jong-Kuk

    2012-05-01

    Full Text Available Abstract Background Papaya is a major fruit crop in tropical and subtropical regions worldwide. It is trioecious with three sex forms: male, female, and hermaphrodite. Sex determination is controlled by a pair of nascent sex chromosomes with two slightly different Y chromosomes, Y for male and Yh for hermaphrodite. The sex chromosome genotypes are XY (male, XYh (hermaphrodite, and XX (female. The papaya hermaphrodite-specific Yh chromosome region (HSY is pericentromeric and heterochromatic. Physical mapping of HSY and its X counterpart is essential for sequencing these regions and uncovering the early events of sex chromosome evolution and to identify the sex determination genes for crop improvement. Results A reiterate chromosome walking strategy was applied to construct the two physical maps with three bacterial artificial chromosome (BAC libraries. The HSY physical map consists of 68 overlapped BACs on the minimum tiling path, and covers all four HSY-specific Knobs. One gap remained in the region of Knob 1, the only knob structure shared between HSY and X, due to the lack of HSY-specific sequences. This gap was filled on the physical map of the HSY corresponding region in the X chromosome. The X physical map consists of 44 BACs on the minimum tiling path with one gap remaining in the middle, due to the nature of highly repetitive sequences. This gap was filled on the HSY physical map. The borders of the non-recombining HSY were defined genetically by fine mapping using 1460 F2 individuals. The genetically defined HSY spanned approximately 8.5 Mb, whereas its X counterpart extended about 5.4 Mb including a 900 Kb region containing the Knob 1 shared by the HSY and X. The 8.5 Mb HSY corresponds to 4.5 Mb of its X counterpart, showing 4 Mb (89% DNA sequence expansion. Conclusion The 89% increase of DNA sequence in HSY indicates rapid expansion of the Yh chromosome after genetic recombination was suppressed 2–3 million years ago. The

  17. Body mass index and physical fitness in Brazilian adolescents.

    Science.gov (United States)

    Lopes, Vitor P; Malina, Robert M; Gomez-Campos, Rossana; Cossio-Bolaños, Marco; Arruda, Miguel de; Hobold, Edilson

    2018-05-05

    Evaluate the relationship between body mass index and physical fitness in a cross-sectional sample of Brazilian youth. Participants were 3849 adolescents (2027 girls) aged 10-17 years. Weight and height were measured; body mass index was calculated. Physical fitness was evaluated with a multistage 20m shuttle run (cardiovascular endurance), standing long jump (power), and push-ups (upper body strength). Participants were grouped by sex into four age groups: 10-11, 12-13, 14-15, and 16-17 years. Sex-specific ANOVA was used to evaluate differences in each physical fitness item among weight status categories by age group. Relationships between body mass index and each physical fitness item were evaluated with quadratic regression models by age group within each sex. The physical fitness of thin and normal youth was, with few exceptions, significantly better than the physical fitness of overweight and obese youth in each age group by sex. On the other hand, physical fitness performances did not consistently differ, on average, between thin and normal weight and between overweight and obese youths. Results of the quadratic regressions indicated a curvilinear (parabolic) relationship between body mass index and each physical fitness item in most age groups. Better performances were attained by adolescents in the mid-range of the body mass index distribution, while performances of youth at the low and high ends of the body mass index distribution were lower. Relationships between the body mass index and physical fitness were generally nonlinear (parabolic) in youth 10-17 years. Copyright © 2018 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  18. Infant sex-specific placental cadmium and DNA methylation associations

    Energy Technology Data Exchange (ETDEWEB)

    Mohanty, April F., E-mail: april.mohanty@va.gov [Cardiovascular Health Research Unit, University of Washington, 1730 Minor Ave, Seattle, WA 98101 (United States); Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA (United States); Farin, Fred M., E-mail: freddy@u.washington.edu [Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, 4225 Roosevelt Way N.E., Suite #100, Seattle, WA 98105 (United States); Bammler, Theo K., E-mail: tbammler@u.washington.edu [Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, 4225 Roosevelt Way N.E., Suite #100, Seattle, WA 98105 (United States); MacDonald, James W., E-mail: jmacdon@uw.edu [Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, 4225 Roosevelt Way N.E., Suite #100, Seattle, WA 98105 (United States); Afsharinejad, Zahra, E-mail: zafshari@u.washington.edu [Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, 4225 Roosevelt Way N.E., Suite #100, Seattle, WA 98105 (United States); Burbacher, Thomas M., E-mail: tmb@uw.edu [Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, Box: 357234, 1705 N.E. Pacific Street, Seattle, WA 98195 (United States); Siscovick, David S., E-mail: dsiscovick@nyam.org [Cardiovascular Health Research Unit, University of Washington, 1730 Minor Ave, Seattle, WA 98101 (United States); Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA (United States); Department of Medicine, University of Washington, Seattle, WA (United States); and others

    2015-04-15

    Background: Recent evidence suggests that maternal cadmium (Cd) burden and fetal growth associations may vary by fetal sex. However, mechanisms contributing to these differences are unknown. Objectives: Among 24 maternal-infant pairs, we investigated infant sex-specific associations between placental Cd and placental genome-wide DNA methylation. Methods: We used ANOVA models to examine sex-stratified associations of placental Cd (dichotomized into high/low Cd using sex-specific Cd median cutoffs) with DNA methylation at each cytosine-phosphate-guanine site or region. Statistical significance was defined using a false discovery rate cutoff (<0.10). Results: Medians of placental Cd among females and males were 5 and 2 ng/g, respectively. Among females, three sites (near ADP-ribosylation factor-like 9 (ARL9), siah E3 ubiquitin protein ligase family member 3 (SIAH3), and heparin sulfate (glucosamine) 3-O-sulfotransferase 4 (HS3ST4) and one region on chromosome 7 (including carnitine O-octanoyltransferase (CROT) and TP5S target 1 (TP53TG1)) were hypomethylated in high Cd placentas. Among males, high placental Cd was associated with methylation of three sites, two (hypomethylated) near MDS1 and EVI1 complex locus (MECOM) and one (hypermethylated) near spalt-like transcription factor 1 (SALL1), and two regions (both hypomethylated, one on chromosome 3 including MECOM and another on chromosome 8 including rho guanine nucleotide exchange factor (GEF) 10 (ARHGEF10). Differentially methylated sites were at or close to transcription start sites of genes involved in cell damage response (SIAH3, HS3ST4, TP53TG1) in females and cell differentiation, angiogenesis and organ development (MECOM, SALL1) in males. Conclusions: Our preliminary study supports infant sex-specific placental Cd-DNA methylation associations, possibly accounting for previously reported differences in Cd-fetal growth associations across fetal sex. Larger studies are needed to replicate and extend these

  19. Infant sex-specific placental cadmium and DNA methylation associations

    International Nuclear Information System (INIS)

    Mohanty, April F.; Farin, Fred M.; Bammler, Theo K.; MacDonald, James W.; Afsharinejad, Zahra; Burbacher, Thomas M.; Siscovick, David S.

    2015-01-01

    Background: Recent evidence suggests that maternal cadmium (Cd) burden and fetal growth associations may vary by fetal sex. However, mechanisms contributing to these differences are unknown. Objectives: Among 24 maternal-infant pairs, we investigated infant sex-specific associations between placental Cd and placental genome-wide DNA methylation. Methods: We used ANOVA models to examine sex-stratified associations of placental Cd (dichotomized into high/low Cd using sex-specific Cd median cutoffs) with DNA methylation at each cytosine-phosphate-guanine site or region. Statistical significance was defined using a false discovery rate cutoff (<0.10). Results: Medians of placental Cd among females and males were 5 and 2 ng/g, respectively. Among females, three sites (near ADP-ribosylation factor-like 9 (ARL9), siah E3 ubiquitin protein ligase family member 3 (SIAH3), and heparin sulfate (glucosamine) 3-O-sulfotransferase 4 (HS3ST4) and one region on chromosome 7 (including carnitine O-octanoyltransferase (CROT) and TP5S target 1 (TP53TG1)) were hypomethylated in high Cd placentas. Among males, high placental Cd was associated with methylation of three sites, two (hypomethylated) near MDS1 and EVI1 complex locus (MECOM) and one (hypermethylated) near spalt-like transcription factor 1 (SALL1), and two regions (both hypomethylated, one on chromosome 3 including MECOM and another on chromosome 8 including rho guanine nucleotide exchange factor (GEF) 10 (ARHGEF10). Differentially methylated sites were at or close to transcription start sites of genes involved in cell damage response (SIAH3, HS3ST4, TP53TG1) in females and cell differentiation, angiogenesis and organ development (MECOM, SALL1) in males. Conclusions: Our preliminary study supports infant sex-specific placental Cd-DNA methylation associations, possibly accounting for previously reported differences in Cd-fetal growth associations across fetal sex. Larger studies are needed to replicate and extend these

  20. A father effect explains sex-ratio bias.

    Science.gov (United States)

    Malo, Aurelio F; Martinez-Pastor, Felipe; Garcia-Gonzalez, Francisco; Garde, Julián; Ballou, Jonathan D; Lacy, Robert C

    2017-08-30

    Sex ratio allocation has important fitness consequences, and theory predicts that parents should adjust offspring sex ratio in cases where the fitness returns of producing male and female offspring vary. The ability of fathers to bias offspring sex ratios has traditionally been dismissed given the expectation of an equal proportion of X- and Y-chromosome-bearing sperm (CBS) in ejaculates due to segregation of sex chromosomes at meiosis. This expectation has been recently refuted. Here we used Peromyscus leucopus to demonstrate that sex ratio is explained by an exclusive effect of the father, and suggest a likely mechanism by which male-driven sex-ratio bias is attained. We identified a male sperm morphological marker that is associated with the mechanism leading to sex ratio bias; differences among males in the sperm nucleus area (a proxy for the sex chromosome that the sperm contains) explain 22% variation in litter sex ratio. We further show the role played by the sperm nucleus area as a mediator in the relationship between individual genetic variation and sex-ratio bias. Fathers with high levels of genetic variation had ejaculates with a higher proportion of sperm with small nuclei area. This, in turn, led to siring a higher proportion of sons (25% increase in sons per 0.1 decrease in the inbreeding coefficient). Our results reveal a plausible mechanism underlying unexplored male-driven sex-ratio biases. We also discuss why this pattern of paternal bias can be adaptive. This research puts to rest the idea that father contribution to sex ratio variation should be disregarded in vertebrates, and will stimulate research on evolutionary constraints to sex ratios-for example, whether fathers and mothers have divergent, coinciding, or neutral sex allocation interests. Finally, these results offer a potential explanation for those intriguing cases in which there are sex ratio biases, such as in humans. © 2017 The Author(s).

  1. Contextual modulation of social and endocrine correlates of fitness: insights from the life history of a sex changing fish

    Directory of Open Access Journals (Sweden)

    Devaleena S Pradhan

    2015-02-01

    Full Text Available Steroid hormones are critical regulators of reproductive life history, and the steroid sensitive traits (morphology, behavior, physiology associated with particular life history stages can have substantial fitness consequences for an organism. Hormones, behavior and fitness are reciprocally associated and can be used in an integrative fashion to understand how the environment impacts organismal function. To address the fitness component, we highlight the importance of using reliable proxies of reproductive success, when studying proximate regulation of reproductive phenotypes. To understand the mechanisms by which the endocrine system regulates phenotype, we discuss the use of particular endocrine proxies and the need for appropriate functional interpretation of each. Lastly, in any experimental paradigm, the responses of animals vary based on the subtle differences in environmental and social context and this must also be considered. We explore these different levels of analyses by focusing on the fascinating life history transitions exhibited by the bi-directionally hermaphroditic fish, Lythrypnus dalli. Sex changing fish are excellent models for providing a deeper understanding of the fitness consequences associated with the behavioral and endocrine variation. We close by proposing that local regulation of steroids is one potential mechanism that allows for the expression of novel phenotypes that can be characteristic of specific life history stages. A comparative species approach will facilitate progress in understanding the diversity of mechanisms underlying the contextual regulation of phenotypes and their associated fitness correlates.

  2. Somatic sex-specific transcriptome differences in Drosophila revealed by whole transcriptome sequencing

    Directory of Open Access Journals (Sweden)

    Arbeitman Michelle N

    2011-07-01

    Full Text Available Abstract Background Understanding animal development and physiology at a molecular-biological level has been advanced by the ability to determine at high resolution the repertoire of mRNA molecules by whole transcriptome resequencing. This includes the ability to detect and quantify rare abundance transcripts and isoform-specific mRNA variants produced from a gene. The sex hierarchy consists of a pre-mRNA splicing cascade that directs the production of sex-specific transcription factors that specify nearly all sexual dimorphism. We have used deep RNA sequencing to gain insight into how the Drosophila sex hierarchy generates somatic sex differences, by examining gene and transcript isoform expression differences between the sexes in adult head tissues. Results Here we find 1,381 genes that differ in overall expression levels and 1,370 isoform-specific transcripts that differ between males and females. Additionally, we find 512 genes not regulated downstream of transformer that are significantly more highly expressed in males than females. These 512 genes are enriched on the × chromosome and reside adjacent to dosage compensation complex entry sites, which taken together suggests that their residence on the × chromosome might be sufficient to confer male-biased expression. There are no transcription unit structural features, from a set of features, that are robustly significantly different in the genes with significant sex differences in the ratio of isoform-specific transcripts, as compared to random isoform-specific transcripts, suggesting that there is no single molecular mechanism that generates isoform-specific transcript differences between the sexes, even though the sex hierarchy is known to include three pre-mRNA splicing factors. Conclusions We identify thousands of genes that show sex-specific differences in overall gene expression levels, and identify hundreds of additional genes that have differences in the abundance of isoform-specific

  3. No evidence for sex-specific effects of the maternal social environment on offspring development in Japanese quail (Coturnix japonica).

    Science.gov (United States)

    Langen, Esther M A; von Engelhardt, Nikolaus; Goerlich-Jansson, Vivian C

    2018-07-01

    The social environment of reproducing females can cause physiological changes, with consequences for reproductive investment and offspring development. These prenatal maternal effects are often found to be sex-specific and may have evolved as adaptations, maximizing fitness of male and female offspring for their future environment. Female hormone levels during reproduction are considered a potential mechanism regulating sex allocation in vertebrates: high maternal androgens have repeatedly been linked to increased investment in sons, whereas high glucocorticoid levels are usually related to increased investment in daughters. However, results are not consistent across studies and therefore still inconclusive. In Japanese quail (Coturnix japonica), we previously found that pair-housed females had higher plasma androgen levels and tended to have higher plasma corticosterone levels than group-housed females. In the current study we investigate whether these differences in maternal social environment and physiology affect offspring sex allocation and physiology. Counter to our expectations, we find no effects of the maternal social environment on offspring sex ratio, sex-specific mortality, growth, circulating androgen or corticosterone levels. Also, maternal corticosterone or androgen levels do not correlate with offspring sex ratio or mortality. The social environment during reproduction therefore does not necessarily modify sex allocation and offspring physiology, even if it causes differences in maternal physiology. We propose that maternal effects of the social environment strongly depend upon the type of social stimuli and the timing of changes in the social environment and hormones with respect to the reproductive cycle and meiosis. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Returns to Tenure, Firm-Specific Human Capital and Worker Heterogeneity

    DEFF Research Database (Denmark)

    Bingley, Paul; Westergård-Nielsen, Niels Chr.

    2003-01-01

    Workers with longer job tenure are paid more, on average, than those with shorter tenure. This paper re-opens the debate about whether individual financial returns to tenure are due to firm-specific human capital accumulation or sorting according to unobserved individual productivity heterogeneity...

  5. Facial Resemblance Exaggerates Sex-Specific Jealousy-Based Decisions1

    OpenAIRE

    Steven M. Platek; Jaime W. Thomson

    2007-01-01

    Sex differences in reaction to a romantic partner's infidelity are well documented and are hypothesized to be attributable to sex-specific jealousy mechanisms which are utilized to solve adaptive problems associated with risk of extra-pair copulation. Males, because of the risk of cuckoldry become more upset by sexual infidelity, while females, because of loss of resources and biparental investment tend to become more distressed by emotional infidelity. However, the degree to which these sex-...

  6. Sex-specific effects of the local social environment on juvenile post-fledging dispersal in great tits

    NARCIS (Netherlands)

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

    2011-01-01

    An individual's decision to disperse from the natal habitat can affect its future fitness prospects. Especially in species with sex-biased dispersal, we expect the cost benefit balance for dispersal to vary according to the social environment (e.g., local sex ratio and density). However, little is

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

    Science.gov (United States)

    Argue, Kathryn J; Neckameyer, Wendi S

    2014-07-01

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

  8. Deletion of Fmr1 results in sex-specific changes in behavior.

    Science.gov (United States)

    Nolan, Suzanne O; Reynolds, Conner D; Smith, Gregory D; Holley, Andrew J; Escobar, Brianna; Chandler, Matthew A; Volquardsen, Megan; Jefferson, Taylor; Pandian, Ashvini; Smith, Tileena; Huebschman, Jessica; Lugo, Joaquin N

    2017-10-01

    In this study, we used a systemic Fmr1 knockout in order to investigate both genotype- and sex-specific differences across multiple measures of sociability, repetitive behaviors, activity levels, anxiety, and fear-related learning and memory. Fragile X syndrome is the most common monogenic cause of intellectual disability and autism. Few studies to date have examined sex differences in a mouse model of Fragile X syndrome, though clinical data support the idea of differences in both overall prevalence and phenotype between the sexes. Using wild-type and systemic homozygous Fmr1 knockout mice, we assessed a variety of behavioral paradigms in adult animals, including the open field test, elevated plus maze, nose-poke assay, accelerating rotarod, social partition task, three-chambered social task, and two different fear conditioning paradigms. Tests were ordered such that the most invasive tests were performed last in the sequence, and testing paradigms for similar behaviors were performed in separate cohorts to minimize testing effects. Our results indicate several sex-specific changes in Fmr1 knockout mice, including male-specific increases in activity levels, and female-specific increases in repetitive behaviors on both the nose-poke assay and motor coordination on the accelerating rotarod task. The results also indicated that Fmr1 deletion results in deficits in fear learning and memory across both sexes, and no changes in social behavior across two tasks. These findings highlight the importance of including female subjects in preclinical studies, as simply studying the impact of genetic mutations in males does not yield a complete picture of the phenotype. Further research should explore these marked phenotypic differences among the sexes. Moreover, given that treatment strategies are typically equivalent between the sexes, the results highlight a potential need for sex-specific therapeutics.

  9. Anthropogenic impacts on Costa Rican bat parasitism are sex specific.

    Science.gov (United States)

    Frank, Hannah K; Mendenhall, Chase D; Judson, Seth D; Daily, Gretchen C; Hadly, Elizabeth A

    2016-07-01

    While anthropogenic impacts on parasitism of wildlife are receiving growing attention, whether these impacts vary in a sex-specific manner remains little explored. Differences between the sexes in the effect of parasites, linked to anthropogenic activity, could lead to uneven sex ratios and higher population endangerment. We sampled 1108 individual bats in 18 different sites across an agricultural mosaic landscape in southern Costa Rica to investigate the relationships between anthropogenic impacts (deforestation and reductions in host species richness) and bat fly ectoparasitism of 35 species of Neotropical bats. Although female and male bat assemblages were similar across the deforestation gradient, bat fly assemblages tracked their hosts closely only on female bats. We found that in female hosts, parasite abundance per bat decreased with increasing bat species richness, while in male hosts, parasite abundance increased. We hypothesize the differences in the parasite-disturbance relationship are due to differences in roosting behavior between the sexes. We report a sex-specific parasite-disturbance relationship and argue that sex differences in anthropogenic impacts on wildlife parasitism could impact long-term population health and survival.

  10. Sport specific fitness testing of elite badminton players.

    Science.gov (United States)

    Chin, M K; Wong, A S; So, R C; Siu, O T; Steininger, K; Lo, D T

    1995-01-01

    There is a scarcity of descriptive data on the performance capacity of elite badminton players, whose fitness requirements are quite specific. The purpose of this paper is to investigate the physiological response of elite badminton players in a sport-specific fitness test. Twelve Hong Kong national badminton team players performed a field test on a badminton court. Six light bulbs were connected to a programming device causing individual bulbs to light up in a given sequence. The players were instructed to react to the flashes by running towards them, and striking shuttles mounted in the vicinity of the bulbs. Exercise intensity was controlled by altering the interval between successive lightings. A low correlation (r = 0.65) was found between the results of the field test and the rank-order list of subjects, based on an objective on-field physiological assessment and subjective ranking. This may be explained by the requirements of other factors besides physical fitness which contribute to success in elite level badminton competition. These factors may include, for example, technical skill, mental power, and aesthetic judgements on the court. Maximum mean (s.d.) heart rate data (187(8) beats.min-1) and blood lactate values (10.4(2.9) mmol.l-1) in this study showed that players were under maximal load during the field test. From the testing data, it seems reasonable to speculate that the intensity of level 3 (20 light pulses.min-1; 3.0 s.pulse-1) and level 4 (22 light pulses.min-1; 2.7 s.pulse-1) simulates the requirement of actual games energy expenditure of the Hong Kong badminton players exercising at close to their anaerobic threshold. The results also show that an estimate of fitness can be derived from measurements involving exercise closely resembling that which is specific for the sports activity in question. Improved training advice and guidance may result from such studies. PMID:8800846

  11. Media device ownership and media use: Associations with sedentary time, physical activity and fitness in English youth

    Directory of Open Access Journals (Sweden)

    Gavin R.H. Sandercock

    2016-12-01

    Higher weekend sedentary time was associated with low fitness in girls (p = 0.005 and boys (p 10 h or ~85% of each waking day sedentary. Use of social media was associated with higher sedentary time in both sexes and with low fitness in girls. Reducing social media use in youth offers one potential target for intervention. Behaviours associated with sedentary time differed from predictors of low fitness. The complex and often sex-specific interactions identified between sedentary time, PA and fitness suggest the need for carefully targeted interventions to reduce sedentary time and improve fitness in English youth.

  12. National and state-specific health insurance disparities for adults in same-sex relationships.

    Science.gov (United States)

    Gonzales, Gilbert; Blewett, Lynn A

    2014-02-01

    We examined national and state-specific disparities in health insurance coverage, specifically employer-sponsored insurance (ESI) coverage, for adults in same-sex relationships. We used data from the American Community Survey to identify adults (aged 25-64 years) in same-sex relationships (n = 31,947), married opposite-sex relationships (n = 3,060,711), and unmarried opposite-sex relationships (n = 259,147). We estimated multinomial logistic regression models and state-specific relative differences in ESI coverage with predictive margins. Men and women in same-sex relationships were less likely to have ESI than were their married counterparts in opposite-sex relationships. We found ESI disparities among adults in same-sex relationships in every region, but we found the largest ESI gaps for men in the South and for women in the Midwest. ESI disparities were narrower in states that had extended legal same-sex marriage, civil unions, and broad domestic partnerships. Men and women in same-sex relationships experience disparities in health insurance coverage across the country, but residing in a state that recognizes legal same-sex marriage, civil unions, or broad domestic partnerships may improve access to ESI for same-sex spouses and domestic partners.

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

    Science.gov (United States)

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

    2013-01-01

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

  14. Fitness consequences of cooperative breeding in the Seychelles warbler

    NARCIS (Netherlands)

    Komdeur, Jan; Richardson, David; Burke, Terry

    2006-01-01

    Inclusive fitness benefits have been suggested as the selective force behind the evolution of cooperative breeding. Assessing the benefits accrued to individual males and females is crucial to understanding the sex-specific helping behavior observed in many cooperatively breeding species. We

  15. Food stress causes sex-specific maternal effects in mites.

    Science.gov (United States)

    Walzer, Andreas; Schausberger, Peter

    2015-08-01

    Life history theory predicts that females should produce few large eggs under food stress and many small eggs when food is abundant. We tested this prediction in three female-biased size-dimorphic predatory mites feeding on herbivorous spider mite prey: Phytoseiulus persimilis, a specialized spider mite predator; Neoseiulus californicus, a generalist preferring spider mites; Amblyseius andersoni, a broad diet generalist. Irrespective of predator species and offspring sex, most females laid only one small egg under severe food stress. Irrespective of predator species, the number of female but not male eggs decreased with increasing maternal food stress. This sex-specific effect was probably due to the higher production costs of large female than small male eggs. The complexity of the response to the varying availability of spider mite prey correlated with the predators' degree of adaptation to this prey. Most A. andersoni females did not oviposit under severe food stress, whereas N. californicus and P. persimilis did oviposit. Under moderate food stress, only P. persimilis increased its investment per offspring, at the expense of egg number, and produced few large female eggs. When prey was abundant, P. persimilis decreased the female egg sizes at the expense of increased egg numbers, resulting in a sex-specific egg size/number trade-off. Maternal effects manifested only in N. californicus and P. persimilis. Small egg size correlated with the body size of daughters but not sons. Overall, our study provides a key example of sex-specific maternal effects, i.e. food stress during egg production more strongly affects the sex of the large than the small offspring. © 2015. Published by The Company of Biologists Ltd.

  16. Exploring Longitudinal Risk-return Relationships

    DEFF Research Database (Denmark)

    Andersen, Torben J.; Bettis, Richard A.

    2015-01-01

    We study a longitudinal fit model of adaptation and its association with the longitudinal risk-return relationship. The model allows the firm to adjust its position in response to partial learning about a changing environment characterized by two path-dependent processes—a random walk and a stoch......We study a longitudinal fit model of adaptation and its association with the longitudinal risk-return relationship. The model allows the firm to adjust its position in response to partial learning about a changing environment characterized by two path-dependent processes—a random walk...... can lead to the inverse longitudinal risk-return relationships observed empirically. We discuss this apparent paradox and the possible resolution between mindless and conscious behavior as plausible causes of the longitudinal Bowman Paradox....

  17. Dutch population specific sex estimation formulae using the proximal femur.

    Science.gov (United States)

    Colman, K L; Janssen, M C L; Stull, K E; van Rijn, R R; Oostra, R J; de Boer, H H; van der Merwe, A E

    2018-05-01

    Sex estimation techniques are frequently applied in forensic anthropological analyses of unidentified human skeletal remains. While morphological sex estimation methods are able to endure population differences, the classification accuracy of metric sex estimation methods are population-specific. No metric sex estimation method currently exists for the Dutch population. The purpose of this study is to create Dutch population specific sex estimation formulae by means of osteometric analyses of the proximal femur. Since the Netherlands lacks a representative contemporary skeletal reference population, 2D plane reconstructions, derived from clinical computed tomography (CT) data, were used as an alternative source for a representative reference sample. The first part of this study assesses the intra- and inter-observer error, or reliability, of twelve measurements of the proximal femur. The technical error of measurement (TEM) and relative TEM (%TEM) were calculated using 26 dry adult femora. In addition, the agreement, or accuracy, between the dry bone and CT-based measurements was determined by percent agreement. Only reliable and accurate measurements were retained for the logistic regression sex estimation formulae; a training set (n=86) was used to create the models while an independent testing set (n=28) was used to validate the models. Due to high levels of multicollinearity, only single variable models were created. Cross-validated classification accuracies ranged from 86% to 92%. The high cross-validated classification accuracies indicate that the developed formulae can contribute to the biological profile and specifically in sex estimation of unidentified human skeletal remains in the Netherlands. Furthermore, the results indicate that clinical CT data can be a valuable alternative source of data when representative skeletal collections are unavailable. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Tick size and stock returns

    Science.gov (United States)

    Onnela, Jukka-Pekka; Töyli, Juuso; Kaski, Kimmo

    2009-02-01

    Tick size is an important aspect of the micro-structural level organization of financial markets. It is the smallest institutionally allowed price increment, has a direct bearing on the bid-ask spread, influences the strategy of trading order placement in electronic markets, affects the price formation mechanism, and appears to be related to the long-term memory of volatility clustering. In this paper we investigate the impact of tick size on stock returns. We start with a simple simulation to demonstrate how continuous returns become distorted after confining the price to a discrete grid governed by the tick size. We then move on to a novel experimental set-up that combines decimalization pilot programs and cross-listed stocks in New York and Toronto. This allows us to observe a set of stocks traded simultaneously under two different ticks while holding all security-specific characteristics fixed. We then study the normality of the return distributions and carry out fits to the chosen distribution models. Our empirical findings are somewhat mixed and in some cases appear to challenge the simulation results.

  19. EMPIRICAL DISTRIBUTION OF STOCK RETURNS OF SOUTHEAST EUROPEAN EMERGING MARKETS

    Directory of Open Access Journals (Sweden)

    Aleksandar Naumoski

    2017-06-01

    Full Text Available The assumption that equity returns follow the normal distribution, most commonly made in financial economics theory and applications, is strongly rejected by empirical evidence presented in this paper. As it was found in many other studies, we confirm that stock returns follow a leptokurtic distribution and skewness, which in most of the Southeast European (SEE markets is negative. This paper investigates further whether there is any distribution that may be considered an optimal fit for stock returns in the SEE region. Using daily, weekly and monthly data samples for a period of five years from ten Southeast European emerging countries, we applied the Anderson-Darling test of Goodness-of-fit. We strongly rejected the aforementioned assumption of normality for all considered data samples and found that the daily stock returns are best fitted by the Johnson SU distribution whereas for the weekly and monthly stock returns there was not one predominant, but many distributions that can be considered a best fit.

  20. Sex-specific gonadal and gene expression changes throughout development in fathead minnow

    Science.gov (United States)

    Although fathead minnows (Pimephales promelas) are commonly used as a model fish in endocrine disruption studies, none have characterized sex-specific baseline expression of genes involved in sex differentiation during development in this species. Using a sex-linked DNA marker t...

  1. Age- and sex-specific thorax finite element model development and simulation.

    Science.gov (United States)

    Schoell, Samantha L; Weaver, Ashley A; Vavalle, Nicholas A; Stitzel, Joel D

    2015-01-01

    The shape, size, bone density, and cortical thickness of the thoracic skeleton vary significantly with age and sex, which can affect the injury tolerance, especially in at-risk populations such as the elderly. Computational modeling has emerged as a powerful and versatile tool to assess injury risk. However, current computational models only represent certain ages and sexes in the population. The purpose of this study was to morph an existing finite element (FE) model of the thorax to depict thorax morphology for males and females of ages 30 and 70 years old (YO) and to investigate the effect on injury risk. Age- and sex-specific FE models were developed using thin-plate spline interpolation. In order to execute the thin-plate spline interpolation, homologous landmarks on the reference, target, and FE model are required. An image segmentation and registration algorithm was used to collect homologous rib and sternum landmark data from males and females aged 0-100 years. The Generalized Procrustes Analysis was applied to the homologous landmark data to quantify age- and sex-specific isolated shape changes in the thorax. The Global Human Body Models Consortium (GHBMC) 50th percentile male occupant model was morphed to create age- and sex-specific thoracic shape change models (scaled to a 50th percentile male size). To evaluate the thoracic response, 2 loading cases (frontal hub impact and lateral impact) were simulated to assess the importance of geometric and material property changes with age and sex. Due to the geometric and material property changes with age and sex, there were observed differences in the response of the thorax in both the frontal and lateral impacts. Material property changes alone had little to no effect on the maximum thoracic force or the maximum percent compression. With age, the thorax becomes stiffer due to superior rotation of the ribs, which can result in increased bone strain that can increase the risk of fracture. For the 70-YO models

  2. A Novel Method for Assessing Sex-Specific and Genotype-Specific Response to Injury in Astrocyte Culture

    Science.gov (United States)

    Liu, Mingyue; Oyarzabal, Esteban; Yang, Rui; Murphy, Stephanie J; Hurn, Patricia D.

    2008-01-01

    Female astrocytes sustain less cell death from oxygen-glucose deprivation (OGD) than male astrocytes. Arimidex, an aromatase inhibitor, abolishes these sex differences. To verify sex-dependent differences in P450 aromatase function in astrocyte cell death following OGD, we developed a novel method that uses sex-specific and genotype-specific single pup primary astrocyte cultures from wild-type (WT) and aromatase-knockout (ArKO) mice. After determining sex by external and internal examination as well as PCR and genotype by PCR amplification of tail cDNA, we established cultures from 1−3 day-old male and female, WT and ArKO mice pups and grew them to confluence in estrogen-free media. Cell death was measured by lactate dehydrogenase (LDH) assay. Our study shows that, while WT female astrocytes are more resistant to OGD than WT male cells, sex differences disappear in ArKO cells. Cell death is significantly increased in ArKO compared to WT in female astrocytes but not male cells. Therefore, P450 aromatase appears to be essential in endogenous neuroprotection in females, and this finding may have clinical implications. This innovative technique may also be applied to other in vitro studies of sex-related functional differences. PMID:18436308

  3. Sex chromosome differentiation and the W- and Z-specific loci in Xenopus laevis.

    Science.gov (United States)

    Mawaribuchi, Shuuji; Takahashi, Shuji; Wada, Mikako; Uno, Yoshinobu; Matsuda, Yoichi; Kondo, Mariko; Fukui, Akimasa; Takamatsu, Nobuhiko; Taira, Masanori; Ito, Michihiko

    2017-06-15

    Genetic sex-determining systems in vertebrates include two basic types of heterogamety; XX (female)/XY (male) and ZZ (male)/ZW (female) types. The African clawed frog Xenopus laevis has a ZZ/ZW-type sex-determining system. In this species, we previously identified a W-specific sex (female)-determining gene dmw, and specified W and Z chromosomes, which could be morphologically indistinguishable (homomorphic). In addition to dmw, we most recently discovered two genes, named scanw and ccdc69w, and one gene, named capn5z in the W- and Z-specific regions, respectively. In this study, we revealed the detail structures of the W/Z-specific loci and genes. Sequence analysis indicated that there is almost no sequence similarity between 278kb W-specific and 83kb Z-specific sequences on chromosome 2Lq32-33, where both the transposable elements are abundant. Synteny and phylogenic analyses indicated that all the W/Z-specific genes might have emerged independently. Expression analysis demonstrated that scanw and ccdc69w or capn5z are expressed in early differentiating ZW gonads or testes, thereby suggesting possible roles in female or male development, respectively. Importantly, the sex-determining gene (SDG) dmw might have been generated after allotetraploidization, thereby indicating the construction of the new sex-determining system by dmw after species hybridization. Furthermore, by direct genotyping, we confirmed that diploid WW embryos developed into normal female frogs, which indicate that the Z-specific region is not essential for female development. Overall, these findings indicate that sex chromosome differentiation has started, although no heteromorphic sex chromosomes are evident yet, in X. laevis. Homologous recombination suppression might have promoted the accumulation of mutations and transposable elements, and enlarged the W/Z-specific regions, thereby resulting in differentiation of the W/Z chromosomes. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Return to Sport-Specific Performance After Primary Anterior Cruciate Ligament Reconstruction: A Systematic Review.

    Science.gov (United States)

    Mohtadi, Nicholas G; Chan, Denise S

    2017-10-01

    Physicians counseling athletes on the prognosis of sport-specific performance outcomes after anterior cruciate ligament reconstruction (ACLR) depend on the published literature. However, critical appraisal of the validity and biases in these studies is required to understand how ACLR affects an athlete's ability to return to sport, the athlete's sport-specific performance, and his or her ability to achieve preinjury levels of performance. This review identifies the published prognostic studies evaluating sport-specific performance outcomes after ACLR. A risk of bias assessment and summaries of return to sport and career longevity results are provided for each included study. Systematic review. Electronic databases (Ovid MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, and PUBMED) were searched via a defined search strategy with no limits, to identify relevant studies for inclusion in the review. A priori defined eligibility criteria included studies measuring sport-specific performance within an athlete's sport, before and after primary ACLR. Reference lists of eligible studies were hand-searched for additional relevant studies. Data extraction was performed by use of a standardized spreadsheet. Each included study was assessed by use of 6 bias domains of the Quality in Prognosis Studies tool to critically appraise study participation, study attrition, prognostic factors, outcome measurement, confounders, and statistical analysis and reporting. Two authors independently performed each stage of the review and reached consensus through discussion. Fifteen pertinent prognostic studies evaluated sport-specific performance outcomes and/or return to play after ACLR for athletes participating in competitive soccer, football, ice hockey, basketball, Alpine ski, X-Games ski and snowboarding, and baseball. Twelve of these studies were considered to have a high level of bias. This review demonstrated that most high

  5. Pre- and postnatal stress and asthma in children: Temporal- and sex-specific associations

    Science.gov (United States)

    Lee, Alison; Chiu, Yueh-Hsiu Mathilda; Rosa, Maria José; Jara, Calvin; Wright, Robert O.; Coull, Brent A.; Wright, Rosalind J.

    2016-01-01

    BACKGROUND Temporal- and sex-specific effects of perinatal stress have not been examined for childhood asthma. OBJECTIVES We examined associations between pre- and/or postnatal stress and children's asthma (n=765) and effect modification by sex in a prospective cohort study. METHODS Maternal negative life events (NLEs) were ascertained prenatally and postpartum. NLEs scores were categorized as 0, 1-2, 3-4, or ≥5 to assess exposure-response relationships. We examined effects of pre- and postnatal stress on children's asthma by age 6 years modeling each as independent predictors; mutually adjusting for prenatal and postnatal stress; and finally considering interactions between pre- and postnatal stress. Effect modification by sex was examined in stratified analyses and by fitting interaction terms. RESULTS When considering stress in each period independently, among boys a dose-response relationship was evident for each level increase on the ordinal scale prenatally (OR=1.38, 95% CI 1.06, 1.79; p-for-trend=0.03) and postnatally (OR=1.53, 95% CI 1.16, 2.01; p-for-trend=0.001); among girls only the postnatal trend was significant (OR=1.60, 95% CI 1.14, 2.22; p-for-trend=0.005). Higher stress in both the pre- and postnatal periods was associated with increased odds of being diagnosed with asthma in girls [OR=1.37, 95% CI 0.98, 1.91 (pinteraction=0.07)] but not boys [OR=1.08, 95% CI 0.82, 1.42 (pinteraction=0.61)]. CONCLUSIONS While boys were more vulnerable to stress during the prenatal period, girls were more impacted by postnatal stress and cumulative stress across both periods in relation to asthma. Understanding sex and temporal differences in response to early life stress may provide unique insight into asthma etiology and natural history. PMID:26953156

  6. Who perpetrates violence against children? A systematic analysis of age-specific and sex-specific data.

    Science.gov (United States)

    Devries, Karen; Knight, Louise; Petzold, Max; Merrill, Katherine G; Maxwell, Lauren; Williams, Abigail; Cappa, Claudia; Chan, Ko Ling; Garcia-Moreno, Claudia; Hollis, NaTasha; Kress, Howard; Peterman, Amber; Walsh, Sophie D; Kishor, Sunita; Guedes, Alessandra; Bott, Sarah; Butron Riveros, Betzabe C; Watts, Charlotte; Abrahams, Naeemah

    2018-01-01

    The epidemiology of violence against children is likely to differ substantially by sex and age of the victim and the perpetrator. Thus far, investment in effective prevention strategies has been hindered by lack of clarity in the burden of childhood violence across these dimensions. We produced the first age-specific and sex-specific prevalence estimates by perpetrator type for physical, sexual and emotional violence against children globally. We used random effects meta-regression to estimate prevalence. Estimates were adjusted for relevant quality covariates, variation in definitions of violence and weighted by region-specific, age-specific and sex-specific population data to ensure estimates reflect country population structures. Secondary data from 600 population or school-based representative datasets and 43 publications obtained via systematic literature review, representing 13 830 estimates from 171 countries. Estimates for recent violence against children aged 0-19 were included. The most common perpetrators of physical and emotional violence for both boys and girls across a range of ages are household members, with prevalence often surpassing 50%, followed by student peers. Children reported experiencing more emotional than physical violence from both household members and students. The most common perpetrators of sexual violence against girls aged 15-19 years are intimate partners; however, few data on other perpetrators of sexual violence against children are systematically collected internationally. Few age-specific and sex-specific data are available on violence perpetration by schoolteachers; however, existing data indicate high prevalence of physical violence from teachers towards students. Data from other authority figures, strangers, siblings and other adults are limited, as are data on neglect of children. Without further investment in data generation on violence exposure from multiple perpetrators for boys and girls of all ages, progress

  7. Who perpetrates violence against children? A systematic analysis of age-specific and sex-specific data

    Science.gov (United States)

    Devries, Karen; Knight, Louise; Petzold, Max; Merrill, Katherine G; Maxwell, Lauren; Williams, Abigail; Cappa, Claudia; Chan, Ko Ling; Garcia-Moreno, Claudia; Hollis, NaTasha; Kress, Howard; Peterman, Amber; Walsh, Sophie D; Kishor, Sunita; Guedes, Alessandra; Bott, Sarah; Butron Riveros, Betzabe C; Watts, Charlotte; Abrahams, Naeemah

    2018-01-01

    Objective The epidemiology of violence against children is likely to differ substantially by sex and age of the victim and the perpetrator. Thus far, investment in effective prevention strategies has been hindered by lack of clarity in the burden of childhood violence across these dimensions. We produced the first age-specific and sex-specific prevalence estimates by perpetrator type for physical, sexual and emotional violence against children globally. Design We used random effects meta-regression to estimate prevalence. Estimates were adjusted for relevant quality covariates, variation in definitions of violence and weighted by region-specific, age-specific and sex-specific population data to ensure estimates reflect country population structures. Data sources Secondary data from 600 population or school-based representative datasets and 43 publications obtained via systematic literature review, representing 13 830 estimates from 171 countries. Eligibility criteria for selecting studies Estimates for recent violence against children aged 0–19 were included. Results The most common perpetrators of physical and emotional violence for both boys and girls across a range of ages are household members, with prevalence often surpassing 50%, followed by student peers. Children reported experiencing more emotional than physical violence from both household members and students. The most common perpetrators of sexual violence against girls aged 15–19 years are intimate partners; however, few data on other perpetrators of sexual violence against children are systematically collected internationally. Few age-specific and sex-specific data are available on violence perpetration by schoolteachers; however, existing data indicate high prevalence of physical violence from teachers towards students. Data from other authority figures, strangers, siblings and other adults are limited, as are data on neglect of children. Conclusions Without further investment in data

  8. A Comparison of Conditional Volatility Estimators for the ISE National 100 Index Returns

    OpenAIRE

    Köksal, Bülent

    2009-01-01

    We compare more than 1000 different volatility models in terms of their fit to the historical ISE-100 Index data and their forecasting performance of the conditional variance in an out-of-sample setting. Exponential GARCH model of Nelson (1991) with “constant mean, t-distribution, one lag moving average term” specification achieves the best overall performance for modeling the ISE-100 return volatility. The t-distribution seems to characterize the distribution of the heavy tailed returns bett...

  9. Human disturbances, habitat characteristics and social environment generate sex-specific responses in vigilance of Mediterranean mouflon.

    Directory of Open Access Journals (Sweden)

    Stéphanie Benoist

    Full Text Available In prey species, vigilance is an important part of the decision making process related to predation risk effects. Therefore, understanding the mechanisms shaping vigilance behavior provides relevant insights on factors influencing individual fitness. We investigated the role of extrinsic and intrinsic factors on vigilance behavior in Mediterranean mouflon (Ovis gmelini musimon×Ovis sp. in a study site spatially and temporally contrasted in human pressures. Both sexes were less vigilant in the wildlife reserve compared to surrounding unprotected areas, except for males during the hunting period. During this period, males tended to be less strictly restricted to the reserve than females what might lead to a pervasive effect of hunting within the protected area, resulting in an increase in male vigilance. It might also be a rutting effect that did not occur in unprotected areas because males vigilance was already maximal in response to human disturbances. In both sexes, yearlings were less vigilant than adults, probably because they traded off vigilance for learning and energy acquisition and/or because they relied on adult experience present in the group. Similarly, non-reproductive females benefited of the vigilance effort provided by reproductive females when belonging to the same group. However, in the absence of reproductive females, non-reproductive females were as vigilant as reproductive females. Increasing group size was only found to reduce vigilance in females (up to 17.5%, not in males. We also showed sex-specific responses to habitat characteristics. Females increased their vigilance when habitat visibility decreased (up to 13.8% whereas males increased their vigilance when feeding on low quality sites, i.e., when concomitant increase in chewing time can be devoted to vigilance with limited costs. Our global approach was able to disentangle the sex-specific sources of variation in mouflon vigilance and stressed the importance of

  10. Sex-specific inhibition and stimulation of worker-reproductive transition in a termite

    Science.gov (United States)

    Sun, Qian; Haynes, Kenneth F.; Hampton, Jordan D.; Zhou, Xuguo

    2017-10-01

    In social insects, the postembryonic development of individuals exhibits strong phenotypic plasticity in response to the environment, thus generating the caste system. Different from eusocial Hymenoptera, in which queens dominate reproduction and inhibit worker fertility, the primary reproductive caste in termites (kings and queens) can be replaced by neotenic reproductives derived from functionally sterile individuals. Feedback regulation of nestmate differentiation into reproductives has been suggested, but the sex specificity remains inconclusive. In the eastern subterranean termite, Reticulitermes flavipes, we tested the hypothesis that neotenic reproductives regulate worker-reproductive transition in a sex-specific manner. With this R. flavipes system, we demonstrate a sex-specific regulatory mechanism with both inhibitory and stimulatory functions. Neotenics inhibit workers of the same sex from differentiating into additional reproductives but stimulate workers of the opposite sex to undergo this transition. Furthermore, this process is not affected by the presence of soldiers. Our results highlight the reproductive plasticity of termites in response to social cues and provide insights into the regulation of reproductive division of labor in a hemimetabolous social insect.

  11. Sex-specific differences in the synaptonemal complex in the genus Oreochromis (Cichlidae).

    Science.gov (United States)

    Campos-Ramos, Rafael; Harvey, Simon C; Penman, David J

    2009-04-01

    Total synaptonemal complex (SC) lengths were estimated from Oreochromis aureus Steindachner (which has a WZ/ZZ sex determination system), O. mossambicus Peters and O. niloticus L. (both of which have XX/XY sex determination systems). The total SC length in oocytes was greater than that in spermatocytes in all three species (194 +/- 30 microm and 134 +/- 13 microm, 187 +/- 22 microm and 127 +/- 17 microm, 193 +/- 37 microm and 144 +/- 19 microm, respectively). These sex-specific differences did not appear to be influenced by the type of sex determination system (the female/male total SC length ratio was 1.45 in O. aureus, 1.47 in O. mossambicus and 1.34 in O. niloticus) and do not correlate with the lack of any overall sex-specific length differences in the current Oreochromis linkage map. Although based on data from relatively few species, there appears to be no consistent relationship between sex-specific SC lengths and linkage map lengths in fish. Neomale (hormonally masculinized genetic female) O. aureus and O. mossambicus had total SC lengths of 138 +/- 13 microm and 146 +/- 13 microm respectively, more similar to normal males than to normal females. These findings agree with data from other vertebrate species that suggest that phenotypic sex, rather than genotype, determines traits such as total SC length, chiasmata position and recombination pattern, at least for the autosomes.

  12. Sex-specific hippocampal 5-hydroxymethylcytosine is disrupted in response to acute stress.

    Science.gov (United States)

    Papale, Ligia A; Li, Sisi; Madrid, Andy; Zhang, Qi; Chen, Li; Chopra, Pankaj; Jin, Peng; Keleş, Sündüz; Alisch, Reid S

    2016-12-01

    Environmental stress is among the most important contributors to increased susceptibility to develop psychiatric disorders. While it is well known that acute environmental stress alters gene expression, the molecular mechanisms underlying these changes remain largely unknown. 5-hydroxymethylcytosine (5hmC) is a novel environmentally sensitive epigenetic modification that is highly enriched in neurons and is associated with active neuronal transcription. Recently, we reported a genome-wide disruption of hippocampal 5hmC in male mice following acute stress that was correlated to altered transcript levels of genes in known stress related pathways. Since sex-specific endocrine mechanisms respond to environmental stimulus by altering the neuronal epigenome, we examined the genome-wide profile of hippocampal 5hmC in female mice following exposure to acute stress and identified 363 differentially hydroxymethylated regions (DhMRs) linked to known (e.g., Nr3c1 and Ntrk2) and potentially novel genes associated with stress response and psychiatric disorders. Integration of hippocampal expression data from the same female mice found stress-related hydroxymethylation correlated to altered transcript levels. Finally, characterization of stress-induced sex-specific 5hmC profiles in the hippocampus revealed 778 sex-specific acute stress-induced DhMRs some of which were correlated to altered transcript levels that produce sex-specific isoforms in response to stress. Together, the alterations in 5hmC presented here provide a possible molecular mechanism for the adaptive sex-specific response to stress that may augment the design of novel therapeutic agents that will have optimal effectiveness in each sex. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  13. The importance of sex-specific quantitative criteria in thallium-201 myocardial scintigraphy

    International Nuclear Information System (INIS)

    Rabinovitch, M.A.; Suissa, S.; Elstein, J.; Turek, M.; Addas, A.; Burgess, J.H.; Rosenthall, L.

    1984-01-01

    Breast attenuation is an important cause of artifactual cold spots on visually interpreted TL-201 myocardial images. This study was undertaken to determine the need for sex-specific criteria in the quantitative analysis of exercise-redistribution TL-201 myocardial scintigraphy (SCINT). The studies of 13 normal females (F) and 12 normal males (M) were processed according to the method of a previous study. Significant sexual differences were found in 7/12 regional uptake (U) proportions, 9/11 regional washout (WO) percentages, 0/3 image redistribution indices, and 0/1 lung to heart ratio. The differences primarily reflected a proportionately decreased anterior and septal uptake in F, a proportionately decreased inferior and inferoapical U in M, and faster WO in F. Sex-specific and total population normal boundaries were set a +- 3SD of the mean for each parameter. Sex-specific boundaries were narrower, and, for 5 parameters (4U and 1WO), contained within the total population boundaries. It was estimated that these differences in boundaries would result in a 6 to 25% discrepancy in patient classification. These results predict that a subset of M and F with coronary artery stenoses could be misclassified as normal by total population criteria, while properly classified as abnormal by sex-specific criteria. The authors conclude that since important differences exist between M and F in the detected pattern of TL-201 myocardial U and WO, sex-specific cr4iteria may enhance the predictive accuracy of SCINT

  14. Stage- and sex-specific heat tolerance in the yellow dung fly Scathophaga stercoraria.

    Science.gov (United States)

    Blanckenhorn, Wolf U; Gautier, Roland; Nick, Marcel; Puniamoorthy, Nalini; Schäfer, Martin A

    2014-12-01

    Thermal tolerance varies at all hierarchical levels of biological organization: among species, populations, individuals, and even within individuals. Age- or developmental stage- and sex-specific thermal effects have received relatively little attention in the literature, despite being crucial for understanding thermal adaptation in nature and responses to global warming. We document stage- and sex- specific heat tolerance in the yellow dung fly Scathophaga stercoraria (Diptera: Scathophagidae), a species common throughout the northern hemisphere that generally favours cool climates. Exposure of eggs to temperatures up to 32°C did not affect larval hatching rate, but subsequent egg-to-adult survival at a benign temperature was reduced. Permanent transfer from benign (18°C) to hot temperatures (up to 31°C) at different larval and pupal stages strongly decreased egg-to-adult survival, though survival continuously improved the later the transfer occurred. Temporary transfer for only two days increased mortality more weakly, survival being lowest when temperature stress was imposed early during the larval or pupal stages. Adult flies provided with sugar and water tolerated 31°C longer than previously thought (5 days in males to 9 days in females). Eggs were thus less susceptible to thermal stress than larvae, pupae or adults, in agreement with the hypothesis that more mobile stages require less physiological protection against heat because they can behaviourally thermoregulate. The probability of mating, of laying a clutch, and hatching success were generally independently reduced by exposure of females or males to warm temperatures (24°C) during the juvenile or adult stages, with some interactions evident. High temperature stress thus affects survival differentially depending on when it occurs during the juvenile or the pre-reproductive adult life stage, and affects reproductive success via the mating behaviour of both sexes, female physiology in terms of

  15. Sex-Specific Associations Between Thyrotropin and Serum Lipid Profiles

    DEFF Research Database (Denmark)

    Meisinger, Christa; Ittermann, Till; Tiller, Daniel

    2014-01-01

    BACKGROUND: Population-based studies investigating the sex-specific association between thyrotropin (TSH) levels and serum lipid concentrations are scarce. We examined the association between TSH and total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL......) cholesterol, and triglycerides in men and women from the general population. Furthermore, the association with TSH outside and within the reference range and lipid levels was studied. METHODS: Individual data of 13,571 men and women without lipid medication of four population-based studies conducted...... in Western European adults were pooled for cross-sectional analyses. The association between TSH levels and lipid concentrations were analyzed by calculating sex-specific multivariable median regression models. RESULTS: In the pooled population, serum TSH levels were significantly positively associated...

  16. Sex-specific genetic effects in physical activity: results from a quantitative genetic analysis.

    Science.gov (United States)

    Diego, Vincent P; de Chaves, Raquel Nichele; Blangero, John; de Souza, Michele Caroline; Santos, Daniel; Gomes, Thayse Natacha; dos Santos, Fernanda Karina; Garganta, Rui; Katzmarzyk, Peter T; Maia, José A R

    2015-08-01

    The objective of this study is to present a model to estimate sex-specific genetic effects on physical activity (PA) levels and sedentary behaviour (SB) using three generation families. The sample consisted of 100 families covering three generations from Portugal. PA and SB were assessed via the International Physical Activity Questionnaire short form (IPAQ-SF). Sex-specific effects were assessed by genotype-by-sex interaction (GSI) models and sex-specific heritabilities. GSI effects and heterogeneity were tested in the residual environmental variance. SPSS 17 and SOLAR v. 4.1 were used in all computations. The genetic component for PA and SB domains varied from low to moderate (11% to 46%), when analyzing both genders combined. We found GSI effects for vigorous PA (p = 0.02) and time spent watching television (WT) (p < 0.001) that showed significantly higher additive genetic variance estimates in males. The heterogeneity in the residual environmental variance was significant for moderate PA (p = 0.02), vigorous PA (p = 0.006) and total PA (p = 0.001). Sex-specific heritability estimates were significantly higher in males only for WT, with a male-to-female difference in heritability of 42.5 (95% confidence interval: 6.4, 70.4). Low to moderate genetic effects on PA and SB traits were found. Results from the GSI model show that there are sex-specific effects in two phenotypes, VPA and WT with a stronger genetic influence in males.

  17. Untangling the Contributions of Sex-Specific Gene Regulation and X-Chromosome Dosage to Sex-Biased Gene Expression in Caenorhabditis elegans

    Science.gov (United States)

    Kramer, Maxwell; Rao, Prashant; Ercan, Sevinc

    2016-01-01

    Dosage compensation mechanisms equalize the level of X chromosome expression between sexes. Yet the X chromosome is often enriched for genes exhibiting sex-biased, i.e., imbalanced expression. The relationship between X chromosome dosage compensation and sex-biased gene expression remains largely unexplored. Most studies determine sex-biased gene expression without distinguishing between contributions from X chromosome copy number (dose) and the animal’s sex. Here, we uncoupled X chromosome dose from sex-specific gene regulation in Caenorhabditis elegans to determine the effect of each on X expression. In early embryogenesis, when dosage compensation is not yet fully active, X chromosome dose drives the hermaphrodite-biased expression of many X-linked genes, including several genes that were shown to be responsible for hermaphrodite fate. A similar effect is seen in the C. elegans germline, where X chromosome dose contributes to higher hermaphrodite X expression, suggesting that lack of dosage compensation in the germline may have a role in supporting higher expression of X chromosomal genes with female-biased functions in the gonad. In the soma, dosage compensation effectively balances X expression between the sexes. As a result, somatic sex-biased expression is almost entirely due to sex-specific gene regulation. These results suggest that lack of dosage compensation in different tissues and developmental stages allow X chromosome copy number to contribute to sex-biased gene expression and function. PMID:27356611

  18. Key to good fit: body measurement problems specific to key ...

    African Journals Online (AJOL)

    Key to good fit: body measurement problems specific to key dimensions. ... to explore and describe the problems that the South African Clothing Industry currently ... A postal survey was conducted among South African apparel and footwear ...

  19. Large scale gene expression meta-analysis reveals tissue-specific, sex-biased gene expression in humans

    Directory of Open Access Journals (Sweden)

    Benjamin Mayne

    2016-10-01

    Full Text Available The severity and prevalence of many diseases are known to differ between the sexes. Organ specific sex-biased gene expression may underpin these and other sexually dimorphic traits. To further our understanding of sex differences in transcriptional regulation, we performed meta-analyses of sex biased gene expression in multiple human tissues. We analysed 22 publicly available human gene expression microarray data sets including over 2500 samples from 15 different tissues and 9 different organs. Briefly, by using an inverse-variance method we determined the effect size difference of gene expression between males and females. We found the greatest sex differences in gene expression in the brain, specifically in the anterior cingulate cortex, (1818 genes, followed by the heart (375 genes, kidney (224 genes, colon (218 genes and thyroid (163 genes. More interestingly, we found different parts of the brain with varying numbers and identity of sex-biased genes, indicating that specific cortical regions may influence sexually dimorphic traits. The majority of sex-biased genes in other tissues such as the bladder, liver, lungs and pancreas were on the sex chromosomes or involved in sex hormone production. On average in each tissue, 32% of autosomal genes that were expressed in a sex-biased fashion contained androgen or estrogen hormone response elements. Interestingly, across all tissues, we found approximately two-thirds of autosomal genes that were sex-biased were not under direct influence of sex hormones. To our knowledge this is the largest analysis of sex-biased gene expression in human tissues to date. We identified many sex-biased genes that were not under the direct influence of sex chromosome genes or sex hormones. These may provide targets for future development of sex-specific treatments for diseases.

  20. Physical fitness reference standards in European children: the IDEFICS study.

    Science.gov (United States)

    De Miguel-Etayo, P; Gracia-Marco, L; Ortega, F B; Intemann, T; Foraita, R; Lissner, L; Oja, L; Barba, G; Michels, N; Tornaritis, M; Molnár, D; Pitsiladis, Y; Ahrens, W; Moreno, L A

    2014-09-01

    A low fitness status during childhood and adolescence is associated with important health-related outcomes, such as increased future risk for obesity and cardiovascular diseases, impaired skeletal health, reduced quality of life and poor mental health. Fitness reference values for adolescents from different countries have been published, but there is a scarcity of reference values for pre-pubertal children in Europe, using harmonised measures of fitness in the literature. The IDEFICS study offers a good opportunity to establish normative values of a large set of fitness components from eight European countries using common and well-standardised methods in a large sample of children. Therefore, the aim of this study is to report sex- and age-specific fitness reference standards in European children. Children (10,302) aged 6-10.9 years (50.7% girls) were examined. The test battery included: the flamingo balance test, back-saver sit-and-reach test (flexibility), handgrip strength test, standing long jump test (lower-limb explosive strength) and 40-m sprint test (speed). Moreover, cardiorespiratory fitness was assessed by a 20-m shuttle run test. Percentile curves for the 1st, 3rd, 10th, 25th, 50th, 75th, 90th, 97th and 99th percentiles were calculated using the General Additive Model for Location Scale and Shape (GAMLSS). Our results show that boys performed better than girls in speed, lower- and upper-limb strength and cardiorespiratory fitness, and girls performed better in balance and flexibility. Older children performed better than younger children, except for cardiorespiratory fitness in boys and flexibility in girls. Our results provide for the first time sex- and age-specific physical fitness reference standards in European children aged 6-10.9 years.

  1. Sex-Specificity of Oxidative Stress in Newborns Leading to a Personalized Antioxidant Nutritive Strategy.

    Science.gov (United States)

    Lavoie, Jean-Claude; Tremblay, André

    2018-03-27

    Oxidative stress is a critical process that triggers several diseases observed in premature infants. Growing recognition of the detriment of oxidative stress in newborns warrants the use of an antioxidant strategy that is likely to be nutritional in order to restore redox homeostasis. It appears essential to have a personalized approach that will take into account the age of gestation at birth and the sex of the infant. However, the link between sex and oxidative stress remains unclear. The aim of this study was to find a common denominator explaining the discrepancy between studies related to sex-specific effects of oxidative stress. Results highlight a specificity of sex in the levels of oxidative stress markers linked to the metabolism of glutathione, as measured in the intracellular compartments. Levels of all sex-dependent oxidative stress markers are greater and markers associated to a better antioxidant defense are lower in boys compared to girls during the neonatal period. This sex-specific discrepancy is likely to be related to estrogen metabolism, which is more active in baby-girls and promotes the activation of glutathione metabolism. our observations suggest that nutritive antioxidant strategies need to target glutathione metabolism and, therefore, should be personalized considering, among others, the sex specificity.

  2. Sex-Specificity of Oxidative Stress in Newborns Leading to a Personalized Antioxidant Nutritive Strategy

    Directory of Open Access Journals (Sweden)

    Jean-Claude Lavoie

    2018-03-01

    Full Text Available Oxidative stress is a critical process that triggers several diseases observed in premature infants. Growing recognition of the detriment of oxidative stress in newborns warrants the use of an antioxidant strategy that is likely to be nutritional in order to restore redox homeostasis. It appears essential to have a personalized approach that will take into account the age of gestation at birth and the sex of the infant. However, the link between sex and oxidative stress remains unclear. The aim of this study was to find a common denominator explaining the discrepancy between studies related to sex-specific effects of oxidative stress. Results highlight a specificity of sex in the levels of oxidative stress markers linked to the metabolism of glutathione, as measured in the intracellular compartments. Levels of all sex-dependent oxidative stress markers are greater and markers associated to a better antioxidant defense are lower in boys compared to girls during the neonatal period. This sex-specific discrepancy is likely to be related to estrogen metabolism, which is more active in baby-girls and promotes the activation of glutathione metabolism. Conclusion: our observations suggest that nutritive antioxidant strategies need to target glutathione metabolism and, therefore, should be personalized considering, among others, the sex specificity.

  3. Production of high quality distillate to meet a fit-for-purpose boiler feedwater specification

    Energy Technology Data Exchange (ETDEWEB)

    Minnich, K. [Veolia Water Solutions Oil and Gas, Calgary, AB (Canada); Neu, D. [Veolia Water Solutions and Technologies/HPD, Pewaukee, WI (United States); Drone, J.L. [Veolia Water Solutions and Technologies/HPD, Plainfield, IL (United States)

    2009-07-01

    Veolia Water Solutions and Technologies has significant experience managing boiler water chemistry and is the world's largest manufacturer of evaporation systems. The company has conducted extensive testing and analysis for produced water evaporation distillate from multiple facilities. In order to produce boiler feed water, evaporation of produced water is used at several steam assisted gravity drainage (SAGD) facilities. There are no official guidelines for the required quality of evaporator distillate to feed a once through steam generator (OTSG) or high pressure industrial watertube boiler (IWT) that will produce injection steam. This paper presented a basis for a fit-for-purpose specification for IWT boilers as well as data on the performance of a Vapor Washer, which produces high quality distilled water that meets fit-for-purpose specifications even during normal variations in feed conditions. Specifically, the paper discussed boiler water requirements for steam injection IWTs; the quality of distillate from a produced water evaporator; the benefits of vapour washing to maintain distillate quality; and suggested boiler chemistry limits for a fit-for-purpose specification. Oxygen, iron, and copper were discussed as being implicated with corrosion and reaction in boilers. Hardness contaminants such as calcium and magnesium were also presented. Suggested limits for boiler water in the fit-for-purpose specification were also presented for silica, total alkalinity, free OH alkalinity, and total dissolved solids in steam. It was concluded that foaming episodes can occur in produced water evaporators due to normal variations, and the distillate can fail to meet the fit-for-purpose specification during foam upsets. 3 refs., 9 figs.

  4. Sex-specific markers developed by next-generation sequencing confirmed an XX/XY sex determination system in bighead carp (Hypophthalmichehys nobilis) and silver carp (Hypophthalmichthys molitrix).

    Science.gov (United States)

    Liu, Haiyang; Pang, Meixia; Yu, Xiaomu; Zhou, Ying; Tong, Jingou; Fu, Beide

    2018-01-05

    Sex-specific markers are powerful tools for identifying sex-determination system in various animals. Bighead carp (Hypophthalmichehys nobilis) and silver carp (Hypophthalmichthys molitrix) are two of the most important edible fish in Asia, which have a long juvenility period that can lasts for 4-5 years. In this study, we found one sex-specific marker by next-generation sequencing together with bioinformatics analysis in bighead carp. The male-specific markers were used to perform molecular sexing in the progenies of artificial gynogenetic diploids and found all progenies (n = 160) were females. Meanwhile, around 1 : 1 sex ratio was observed in a total of 579 juvenile offspring from three other families. To further extend the male-specific region, we performed genome walking and got a male-specific sequence of 8,661 bp. Five pairs of primers were designed and could be used to efficiently distinguish males from females in bighead carp and silver carp. The development of these male-specific markers and results of their molecular sexing in different populations provide strong evidence for a sex determination system of female homogametry or male heterogametry (XX/XY) in bighead carp and silver carp. To the best of our knowledge, this is the first report of effective sex-specific markers in these two large carp species. © The Author(s) 2018. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

  5. Seasonal Variation in Parental Care Drives Sex-Specific Foraging by a Monomorphic Seabird.

    Science.gov (United States)

    Burke, Chantelle M; Montevecchi, William A; Regular, Paul M

    2015-01-01

    Evidence of sex-specific foraging in monomorphic seabirds is increasing though the underlying mechanisms remain poorly understood. We investigate differential parental care as a mechanism for sex-specific foraging in monomorphic Common Murres (Uria aalge), where the male parent alone provisions the chick after colony departure. Using a combination of geolocation-immersion loggers and stable isotopes, we assess two hypotheses: the reproductive role specialization hypothesis and the energetic constraint hypothesis. We compare the foraging behavior of females (n = 15) and males (n = 9) during bi-parental at the colony, post-fledging male-only parental care and winter when parental care is absent. As predicted by the reproductive role specialization hypothesis, we found evidence of sex-specific foraging during post-fledging only, the stage with the greatest divergence in parental care roles. Single-parenting males spent almost twice as much time diving per day and foraged at lower quality prey patches relative to independent females. This implies a potential energetic constraint for males during the estimated 62.8 ± 8.9 days of offspring dependence at sea. Contrary to the predictions of the energetic constraint hypothesis, we found no evidence of sex-specific foraging during biparental care, suggesting that male parents did not forage for their own benefit before colony departure in anticipation of post-fledging energy constraints. We hypothesize that unpredictable prey conditions at Newfoundland colonies in recent years may limit male parental ability to allocate additional time and energy to self-feeding during biparental care, without compromising chick survival. Our findings support differential parental care as a mechanism for sex-specific foraging in monomorphic murres, and highlight the need to consider ecological context in the interpretation of sex-specific foraging behavior.

  6. Seasonal Variation in Parental Care Drives Sex-Specific Foraging by a Monomorphic Seabird.

    Directory of Open Access Journals (Sweden)

    Chantelle M Burke

    Full Text Available Evidence of sex-specific foraging in monomorphic seabirds is increasing though the underlying mechanisms remain poorly understood. We investigate differential parental care as a mechanism for sex-specific foraging in monomorphic Common Murres (Uria aalge, where the male parent alone provisions the chick after colony departure. Using a combination of geolocation-immersion loggers and stable isotopes, we assess two hypotheses: the reproductive role specialization hypothesis and the energetic constraint hypothesis. We compare the foraging behavior of females (n = 15 and males (n = 9 during bi-parental at the colony, post-fledging male-only parental care and winter when parental care is absent. As predicted by the reproductive role specialization hypothesis, we found evidence of sex-specific foraging during post-fledging only, the stage with the greatest divergence in parental care roles. Single-parenting males spent almost twice as much time diving per day and foraged at lower quality prey patches relative to independent females. This implies a potential energetic constraint for males during the estimated 62.8 ± 8.9 days of offspring dependence at sea. Contrary to the predictions of the energetic constraint hypothesis, we found no evidence of sex-specific foraging during biparental care, suggesting that male parents did not forage for their own benefit before colony departure in anticipation of post-fledging energy constraints. We hypothesize that unpredictable prey conditions at Newfoundland colonies in recent years may limit male parental ability to allocate additional time and energy to self-feeding during biparental care, without compromising chick survival. Our findings support differential parental care as a mechanism for sex-specific foraging in monomorphic murres, and highlight the need to consider ecological context in the interpretation of sex-specific foraging behavior.

  7. Prenatal and postnatal stress and asthma in children: Temporal- and sex-specific associations.

    Science.gov (United States)

    Lee, Alison; Mathilda Chiu, Yueh-Hsiu; Rosa, Maria José; Jara, Calvin; Wright, Robert O; Coull, Brent A; Wright, Rosalind J

    2016-09-01

    Temporal- and sex-specific effects of perinatal stress have not been examined for childhood asthma. We examined associations between prenatal and/or postnatal stress and children's asthma (n = 765) and effect modification by sex in a prospective cohort study. Maternal negative life events were ascertained prenatally and postpartum. Negative life event scores were categorized as 0, 1 to 2, 3 to 4, or 5 or greater to assess exposure-response relationships. We examined effects of prenatal and postnatal stress on children's asthma by age 6 years, modeling each as independent predictors, mutually adjusting for prenatal and postnatal stress, and finally considering interactions between prenatal and postnatal stress. Effect modification by sex was examined in stratified analyses and by fitting interaction terms. When considering stress in each period independently, among boys, a dose-response relationship was evident for each level increase on the ordinal scale prenatally (odds ratio [OR], 1.38; 95% CI, 1.06-1.79; P value for trend = .03) and postnatally (OR, 1.53; 95% CI, 1.16-2.01; P value for trend = .001); among girls, only the postnatal trend was significant (OR, 1.60; 95% CI, 1.14-2.22; P value for trend = .005). Higher stress in both the prenatal and postnatal periods was associated with increased odds of receiving a diagnosis of asthma in girls (OR, 1.37; 95% CI, 0.98-1.91; Pinteraction = .07) but not boys (OR, 1.08; 95% CI, 0.82-1.42; Pinteraction = .61). Although boys were more vulnerable to stress during the prenatal period, girls were more affected by postnatal stress and cumulative stress across both periods in relation to asthma. Understanding sex and temporal differences in response to early-life stress might provide unique insight into the cause and natural history of asthma. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  8. The sex of specific neurons controls female body growth in Drosophila.

    Science.gov (United States)

    Sawala, Annick; Gould, Alex P

    2017-10-01

    Sexual dimorphisms in body size are widespread throughout the animal kingdom but their underlying mechanisms are not well characterized. Most models for how sex chromosome genes specify size dimorphism have emphasized the importance of gonadal hormones and cell-autonomous influences in mammals versus strictly cell-autonomous mechanisms in Drosophila melanogaster. Here, we use tissue-specific genetics to investigate how sexual size dimorphism (SSD) is established in Drosophila. We find that the larger body size characteristic of Drosophila females is established very early in larval development via an increase in the growth rate per unit of body mass. We demonstrate that the female sex determination gene, Sex-lethal (Sxl), functions in central nervous system (CNS) neurons as part of a relay that specifies the early sex-specific growth trajectories of larval but not imaginal tissues. Neuronal Sxl acts additively in 2 neuronal subpopulations, one of which corresponds to 7 median neurosecretory cells: the insulin-producing cells (IPCs). Surprisingly, however, male-female differences in the production of insulin-like peptides (Ilps) from the IPCs do not appear to be involved in establishing SSD in early larvae, although they may play a later role. These findings support a relay model in which Sxl in neurons and Sxl in local tissues act together to specify the female-specific growth of the larval body. They also reveal that, even though the sex determination pathways in Drosophila and mammals are different, they both modulate body growth via a combination of tissue-autonomous and nonautonomous inputs.

  9. Physical Fitness in Spanish Schoolchildren Aged 6-12 Years: Reference Values of the Battery EUROFIT and Associated Cardiovascular Risk

    Science.gov (United States)

    Gulías-González, Roberto; Sánchez-López, Mairena; Olivas-Bravo, Ángel; Solera-Martínez, Montserrat; Martínez-Vizcaíno, Vicente

    2014-01-01

    Background: Physical fitness is considered an important indicator of health in children. The aims of this study were to (1) provide sex- and age-specific EUROFIT battery levels of fitness in Spanish children; (2) compare Spanish children's fitness levels with those of children from other countries; and (3) determine the percentage of Spanish…

  10. Sex-specific associative learning cues and inclusive fitness benefits in the Seychelles warbler.

    Science.gov (United States)

    Richardson, D S; Burke, T; Komdeurs, J

    2003-09-01

    In cooperative breeding vertebrates, indirect fitness benefits would be maximized by subordinates that accurately assess their relatedness to group offspring and preferentially help more closely related kin. In the Seychelles warbler (Acrocephalus sechellensis), we found a positive relationship between subordinate-nestling kinship (determined using microsatellite marker genotypes) and provisioning rates, but only for female subordinates. Female subordinates that helped were significantly more related to the nestlings than were nonhelpers, and the decision to help appears to be based on associative learning cues. High levels of female infidelity means that subordinates cannot trust their legitimacy through the male line, consequently they appear to use the continued presence of the primary female, but not the primary male, as a reliable cue to determine when to feed nestlings. By using effective discrimination, female subordinates are able to maximize the indirect benefits gained within a cooperative breeding system otherwise driven primarily by direct breeding benefits.

  11. Sex-specific asymmetry in eye development in interspecific hybrids ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Genetics; Volume 94; Issue 3. Sex-specific asymmetry in eye development in interspecific hybrids in the Drosophila bipectinata species complex. Bashisth N. Singh Parul Banerjee. Research Note Volume 94 Issue 3 September 2015 pp 493-495 ...

  12. Sex-specific effects of altered competition on nestling growth and survival: an experimental manipulation of brood size and sex ratio.

    Science.gov (United States)

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

    2009-03-01

    1. An increase of competition among adults or nestlings usually negatively affects breeding output. Yet little is known about the differential effects that competition has on the offspring sexes. This could be important because it may influence parental reproductive decisions. 2. In sexual size dimorphic species, two main contradictory mechanisms are proposed regarding sex-specific effects of competition on nestling performance assuming that parents do not feed their chicks differentially: (i) the larger sex requires more resources to grow and is more sensitive to a deterioration of the rearing conditions ('costly sex hypothesis'); (ii) the larger sex has a competitive advantage in intra-brood competition and performs better under adverse conditions ('competitive advantage hypothesis'). 3. In the present study, we manipulated the level of sex-specific sibling competition in a great tit population (Parus major) by altering simultaneously the brood size and the brood sex ratio on two levels: the nest (competition for food among nestlings) and the woodlot where the parents breed (competition for food among adults). We investigated whether altered competition during the nestling phase affected nestling growth traits and survival in the nest and whether the effects differed between males, the larger sex, and females. 4. We found a strong negative and sex-specific effect of experimental brood size on all the nestling traits. In enlarged broods, sexual size dimorphism was smaller which may have resulted from biased mortality towards the less competitive individuals i.e. females of low condition. No effect of brood sex ratio on nestling growth traits was found. 5. Negative brood size effects on nestling traits were stronger in natural high-density areas but we could not confirm this experimentally. 6. Our results did not support the 'costly sex hypothesis' because males did not suffer from higher mortality under harsh conditions. The 'competitive advantage hypothesis' was

  13. Differential fitness costs of reproduction between the sexes

    OpenAIRE

    Penn, Dustin J.; Smith, Ken R.

    2006-01-01

    Natural selection does not necessarily favor maximal reproduction because reproduction imposes fitness costs, reducing parental survival, and offspring quality. Here, we show that parents in a preindustrial population in North America incurred fitness costs from reproduction, and women incurred greater costs than men. We examined the survivorship and reproductive success (Darwinian fitness) of 21,684 couples married between 1860 and 1895 identified in the Utah Population Database. We found th...

  14. Differential sex-specific effects of oxygen toxicity in human umbilical vein endothelial cells

    International Nuclear Information System (INIS)

    Zhang, Yuhao; Lingappan, Krithika

    2017-01-01

    Despite the well-established sex-specific differences in the incidence of bronchopulmonary dysplasia (BPD), the molecular mechanism(s) behind these are not completely understood. Pulmonary angiogenesis is critical for alveolarization and arrest in vascular development adversely affects lung development. Human neonatal umbilical vein endothelial cells (HUVECs) provide a robust in vitro model for the study of endothelial cell physiology and function. Male and Female HUVECs were exposed to room air (21% O 2 , 5% CO 2 ) or hyperoxia (95% O 2 , 5% CO 2 ) for up to 72 h. Cell viability, proliferation, H 2 O 2 production and angiogenesis were analyzed. Sex-specific differences in the expression of VEGFR2 and modulation of NF-kappa B pathway were measured. Male HUVECs have decreased survival, greater oxidative stress and impairment in angiogenesis compared to similarly exposed female cells. There is differential expression of VEGFR2 between male and female HUVECs and greater activation of the NF-kappa B pathway in female HUVECs under hyperoxic conditions. The results indicate that sex differences exist between male and female HUVECs in vitro after hyperoxia exposure. Since endothelial dysfunction has a major role in the pathogenesis of BPD, these differences could explain in part the mechanisms behind sex-specific differences in the incidence of this disease. - Highlights: • Cellular sex effects viability and oxidative stress in HUVECs exposed to hyperoxia. • Male HUVECs show greater impairment in angiogenesis compared to female cells. • Sex-specific modulation of VEGFR2 and the NF-kappaB pathway was noted.

  15. Estimation of return levels against different return periods of extreme annual rainfall over Baluchistan

    International Nuclear Information System (INIS)

    Ali, M.; Jan, B.; Iqbal, J.

    2012-01-01

    Unprecedented heavy monsoon rainfall began in the last week of July 2010 in the Northern part of our country, causes floods in Baluchistan and Sindh. As the high frequency rainfall events are a significant cause of current severe flooding in Pakistan and any fluctuation in the level of such events may cause huge economic losses as well as social problem, urban structures (i.e. dams, urban drainage systems and flood). Statistical distributions are used to identify extremes of annual rainfall of different cities of Baluchistan (Quetta, Sibbi, Khuzdar, Lasbella, Dalbandin and Pasni) with their return periods. Analysis predicts that Gumbel Max. (GM) Distribution is the best fitted distribution for Sibbi and Lasbella while the GEV distribution is the best fitted for Quetta, Khuzdar, Dalbandin and Pasni. The analysis also suggests that different cities of Baluchistan have 30-years return period for getting more than 90 mm average daily rainfall while they have 100-years return period for receiving more than 118 mm daily rainfall. This suggests for suitable flood forecasting and improving the river structure in Baluchistan, Pakistan. (author)

  16. Maximum-likelihood fitting of data dominated by Poisson statistical uncertainties

    International Nuclear Information System (INIS)

    Stoneking, M.R.; Den Hartog, D.J.

    1996-06-01

    The fitting of data by χ 2 -minimization is valid only when the uncertainties in the data are normally distributed. When analyzing spectroscopic or particle counting data at very low signal level (e.g., a Thomson scattering diagnostic), the uncertainties are distributed with a Poisson distribution. The authors have developed a maximum-likelihood method for fitting data that correctly treats the Poisson statistical character of the uncertainties. This method maximizes the total probability that the observed data are drawn from the assumed fit function using the Poisson probability function to determine the probability for each data point. The algorithm also returns uncertainty estimates for the fit parameters. They compare this method with a χ 2 -minimization routine applied to both simulated and real data. Differences in the returned fits are greater at low signal level (less than ∼20 counts per measurement). the maximum-likelihood method is found to be more accurate and robust, returning a narrower distribution of values for the fit parameters with fewer outliers

  17. Sex-differences and temporal consistency in stickleback fish boldness.

    Directory of Open Access Journals (Sweden)

    Andrew J King

    Full Text Available Behavioural traits that co-vary across contexts or situations often reflect fundamental trade-offs which individuals experience in different contexts (e.g. fitness trade-offs between exploration and predation risk. Since males tend to experience greater variance in reproductive success than females, there may be considerable fitness benefits associated with "bolder" behavioural types, but only recently have researchers begun to consider sex-specific and life-history strategies associated with these. Here we test the hypothesis that male three-spined sticklebacks (Gasterosteus aculeatus show high risk but potentially high return behaviours compared to females. According to this hypothesis we predicted that male fish would show greater exploration of their environment in a foraging context, and be caught sooner by an experimenter than females. We found that the time fish spent out of cover exploring their environment was correlated over two days, and males spent significantly more time out of cover than females. Also, the order in which fish were net-caught from their holding aquarium by an experimenter prior to experiments was negatively correlated with the time spent out of cover during tests, and males tended to be caught sooner than females. Moreover, we found a positive correlation between the catch number prior to our experiments and nine months after, pointing towards consistent, long-term individual differences in behaviour.

  18. Probability distribution of extreme share returns in Malaysia

    Science.gov (United States)

    Zin, Wan Zawiah Wan; Safari, Muhammad Aslam Mohd; Jaaman, Saiful Hafizah; Yie, Wendy Ling Shin

    2014-09-01

    The objective of this study is to investigate the suitable probability distribution to model the extreme share returns in Malaysia. To achieve this, weekly and monthly maximum daily share returns are derived from share prices data obtained from Bursa Malaysia over the period of 2000 to 2012. The study starts with summary statistics of the data which will provide a clue on the likely candidates for the best fitting distribution. Next, the suitability of six extreme value distributions, namely the Gumbel, Generalized Extreme Value (GEV), Generalized Logistic (GLO) and Generalized Pareto (GPA), the Lognormal (GNO) and the Pearson (PE3) distributions are evaluated. The method of L-moments is used in parameter estimation. Based on several goodness of fit tests and L-moment diagram test, the Generalized Pareto distribution and the Pearson distribution are found to be the best fitted distribution to represent the weekly and monthly maximum share returns in Malaysia stock market during the studied period, respectively.

  19. Stage- and sex-specific heat tolerance in the yellow dung fly Scathophaga stercoraria

    OpenAIRE

    Blanckenhorn Wolf U.; Gautier Roland; Nick Marcel; Puniamoorthy Nalini; Schäfer Martin A.

    2014-01-01

    Thermal tolerance varies at all hierarchical levels of biological organization: among species populations individuals and even within individuals. Age or developmental stage and sex specific thermal effects have received relatively little attention in the literature despite being crucial for understanding thermal adaptation in nature and responses to global warming. We document stage and sex specific heat tolerance in the yellow dung fly Scathophaga stercoraria (Diptera: Scathophagidae) a...

  20. Predicting psychiatric readmission: sex-specific models to predict 30-day readmission following acute psychiatric hospitalization.

    Science.gov (United States)

    Barker, Lucy Church; Gruneir, Andrea; Fung, Kinwah; Herrmann, Nathan; Kurdyak, Paul; Lin, Elizabeth; Rochon, Paula A; Seitz, Dallas; Taylor, Valerie H; Vigod, Simone N

    2018-02-01

    Psychiatric readmission is a common negative outcome. Predictors of readmission may differ by sex. This study aimed to derive and internally validate sex-specific models to predict 30-day psychiatric readmission. We used population-level health administrative data to identify predictors of 30-day psychiatric readmission among women (n = 33,353) and men (n = 32,436) discharged from all psychiatric units in Ontario, Canada (2008-2011). Predictor variables included sociodemographics, health service utilization, and clinical characteristics. Using derivation data sets, multivariable logistic regression models were fit to determine optimal predictive models for each sex separately. Results were presented as adjusted odds ratios (aORs) and 95% confidence intervals (CI). The multivariable models were then applied in the internal validation data sets. The 30-day readmission rates were 9.3% (women) and 9.1% (men). Many predictors were consistent between women and men. For women only, personality disorder (aOR 1.21, 95% CI 1.03-1.42) and positive symptom score (aOR 1.41, 95% CI 1.09-1.82 for score of 1 vs. 0; aOR 1.44, 95% CI 1.26-1.64 for ≥ 2 vs. 0) increased odds of readmission. For men only, self-care problems at admission (aOR 1.20, 95% CI 1.06-1.36) and discharge (aOR 1.44, 95% CI 1.26-1.64 for score of 1 vs. 0; aOR 1.79, 95% CI 1.17-2.74 for 2 vs. 0), and mild anxiety rating (score of 1 vs. 0: aOR 1.30, 95% CI 1.02-1.64, derivation model only) increased odds of readmission. Models had moderate discriminative ability in derivation and internal validation samples for both sexes (c-statistics 0.64-0.65). Certain key predictors of psychiatric readmission differ by sex. This knowledge may help to reduce psychiatric hospital readmission rates by focusing interventions.

  1. Sex-Specificity of Mineralocorticoid Target Gene Expression during Renal Development, and Long-Term Consequences

    Science.gov (United States)

    Dumeige, Laurence; Storey, Caroline; Decourtye, Lyvianne; Nehlich, Melanie; Lhadj, Christophe; Viengchareun, Say; Kappeler, Laurent; Lombès, Marc; Martinerie, Laetitia

    2017-01-01

    Sex differences have been identified in various biological processes, including hypertension. The mineralocorticoid signaling pathway is an important contributor to early arterial hypertension, however its sex-specific expression has been scarcely studied, particularly with respect to the kidney. Basal systolic blood pressure (SBP) and heart rate (HR) were measured in adult male and female mice. Renal gene expression studies of major players of mineralocorticoid signaling were performed at different developmental stages in male and female mice using reverse transcription quantitative PCR (RT-qPCR), and were compared to those of the same genes in the lung, another mineralocorticoid epithelial target tissue that regulates ion exchange and electrolyte balance. The role of sex hormones in the regulation of these genes was also investigated in differentiated KC3AC1 renal cells. Additionally, renal expression of the 11 β-hydroxysteroid dehydrogenase type 2 (11βHSD2) protein, a regulator of mineralocorticoid specificity, was measured by immunoblotting and its activity was indirectly assessed in the plasma using liquid-chromatography coupled to mass spectrometry in tandem (LC-MSMS) method. SBP and HR were found to be significantly lower in females compared to males. This was accompanied by a sex- and tissue-specific expression profile throughout renal development of the mineralocorticoid target genes serum and glucocorticoid-regulated kinase 1 (Sgk1) and glucocorticoid-induced leucine zipper protein (Gilz), together with Hsd11b2, Finally, the implication of sex hormones in this sex-specific expression profile was demonstrated in vitro, most notably for Gilz mRNA expression. We demonstrate a tissue-specific, sex-dependent and developmentally-regulated pattern of expression of the mineralocorticoid pathway that could have important implications in physiology and pathology. PMID:28230786

  2. What was the ancestral sex-determining mechanism in amniote vertebrates?

    Science.gov (United States)

    Johnson Pokorná, Martina; Kratochvíl, Lukáš

    2016-02-01

    Amniote vertebrates, the group consisting of mammals and reptiles including birds, possess various mechanisms of sex determination. Under environmental sex determination (ESD), the sex of individuals depends on the environmental conditions occurring during their development and therefore there are no sexual differences present in their genotypes. Alternatively, through the mode of genotypic sex determination (GSD), sex is determined by a sex-specific genotype, i.e. by the combination of sex chromosomes at various stages of differentiation at conception. As well as influencing sex determination, sex-specific parts of genomes may, and often do, develop specific reproductive or ecological roles in their bearers. Accordingly, an individual with a mismatch between phenotypic (gonadal) and genotypic sex, for example an individual sex-reversed by environmental effects, should have a lower fitness due to the lack of specialized, sex-specific parts of their genome. In this case, evolutionary transitions from GSD to ESD should be less likely than transitions in the opposite direction. This prediction contrasts with the view that GSD was the ancestral sex-determining mechanism for amniote vertebrates. Ancestral GSD would require several transitions from GSD to ESD associated with an independent dedifferentiation of sex chromosomes, at least in the ancestors of crocodiles, turtles, and lepidosaurs (tuataras and squamate reptiles). In this review, we argue that the alternative theory postulating ESD as ancestral in amniotes is more parsimonious and is largely concordant with the theoretical expectations and current knowledge of the phylogenetic distribution and homology of sex-determining mechanisms. © 2014 Cambridge Philosophical Society.

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

    Science.gov (United States)

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

    2018-02-01

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

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

    NARCIS (Netherlands)

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

    2013-01-01

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

  5. Evolution of Sex Differences in Trait- and Age-Specific Vulnerabilities.

    Science.gov (United States)

    Geary, David C

    2016-11-01

    Traits that facilitate competition for reproductive resources or that influence mate choice generally have a heightened sensitivity to stressors. They have evolved to signal resilience to infectious disease and nutritional and social stressors, and they are compromised by exposure to man-made toxins. Although these traits can differ from one species or sex to the next, an understanding of the dynamics of competition and choice can in theory be used to generate a priori predictions about sex-, age-, and trait-specific vulnerabilities for any sexually reproducing species. I provide a review of these dynamics and illustrate associated vulnerabilities in nonhuman species. The age- and sex-specific vulnerability of such traits is then illustrated for stressor-related disruptions of boys' and girls' physical growth and play behavior, as well as for aspects of boys' and girls' and men's and women's personality, language, and spatial abilities. There is much that remains to be determined, but enough is now known to reframe trait sensitivity in ways that will allow scientists and practitioners to better identify and understand vulnerable human traits, and eventually ameliorate or prevent their expression. © The Author(s) 2016.

  6. Physical fitness and anthropometric normative values among Colombian-Indian schoolchildren

    Directory of Open Access Journals (Sweden)

    Jeison Alexander Ramos-Sepúlveda

    2016-09-01

    Full Text Available Abstract Background Substantial evidence indicates that children’s physical fitness levels are markers of their lifestyles and their cardio-metabolic health profile and are predictors of the future risk of chronic diseases such as obesity, cardiometabolic disease, skeletal health and mental health. However, fitness reference values for ethnic children and adolescents have not been published in a Latin-American population. Therefore, the aim of the study was to provide sex- and age-specific physical fitness and anthropometric reference standards among Colombian-Indian schoolchildren. Methods A sample of 576 participants (319 boys and 257 girls aged 10 to 17 years old was assessed using the FUPRECOL test battery. Four components of physical fitness were measured: 1 morphological component: height, weight, body mass index (BMI, waist circumference (WC, triceps skinfold, subscapular skinfold, and body fat (%; 2 musculoskeletal component: handgrip and standing long jump test; 3 motor component: speed/agility test (4 × 10 m shuttle run; and 4 cardiorespiratory component: course-navette 20 m, shuttle run test and estimation of maximal oxygen consumption by VO2max indirect. Centile smoothed curves for the 3rd, 10th, 25th, 50th, 75th, 90th and 97th percentiles were calculated using Cole’s LMS method. Results Our results show that weight, height and BMI in each age group were higher in boys than in girls. In each groups, age showed a significant effect for BMI and WC. Boys showed better than girls in cardiorespiratory fitness, lower- and upper-limb strength and speed/agility and girls performed better in low back flexibility. Conclusion Our results provide for the first time sex- and age-specific physical fitness and anthropometric reference values for Colombian Nasa Indian children and adolescents aged 10–17.9 years.

  7. Expected commodity returns and pricing models

    International Nuclear Information System (INIS)

    Cortazar, Gonzalo; Kovacevic, Ivo; Schwartz, Eduardo S.

    2015-01-01

    Stochastic models of commodity prices have evolved considerably in terms of their structure and the number and interpretation of the state variables that model the underlying risk. Using multiple factors, different specifications and modern estimation techniques, these models have gained wide acceptance because of their success in accurately fitting the observed commodity futures' term structures and their dynamics. It is not well emphasized however that these models, in addition to providing the risk neutral distribution of future spot prices, also provide their true distribution. While the parameters of the risk neutral distribution are estimated more precisely and are usually statistically significant, some of the parameters of the true distribution are typically measured with large errors and are statistically insignificant. In this paper we argue that to increase the reliability of commodity pricing models, and therefore their use by practitioners, some of their parameters — in particular the risk premium parameters — should be obtained from other sources and we show that this can be done without losing any precision in the pricing of futures contracts. We show how the risk premium parameters can be obtained from estimations of expected futures returns and provide alternative procedures for estimating these expected futures returns. - Highlights: • Simple methodology to improve the performance of commodity pricing models • New information about commodity futures expected return is added to the estimation. • No significant effect in pricing futures contracts is observed. • More reliable commodity pricing model's expected returns are obtained. • Methodology is open to any expected futures return model preferred by practitioner

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

    Science.gov (United States)

    Becks, Lutz; Agrawal, Aneil F

    2012-01-01

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

  9. Relationship between functional fitness, medication costs and mood in elderly people

    Directory of Open Access Journals (Sweden)

    Michelli Luciana Massolini Laureano

    2014-06-01

    Full Text Available Objective: to verify if functional fitness (FF is associated with the annual cost of medication consumption and mood states (MSt in elderly people. Methods: a cross-sectional study with 229 elderly people aged 65 years or more at Santa Casa de Misericórdia de Coimbra, Portugal. Seniors with physical and psychological limitations were excluded, as well as those using medication that limits performance on the tests. The Senior Fitness Test was used to evaluate FF, and the Profile of Mood States - Short Form to evaluate the MSt. The statistical analysis was based on Mancova, with adjustment for age, for comparison between men and women, and adjustment for sex, for comparison between cardiorespiratory fitness quintiles. The association between the variables under study was made with partial correlation, controlling for the effects of age, sex and body mass index. Results: an inverse correlation between cardiorespiratory fitness and the annual cost of medication consumption was found (p < 0.01. FF is also inversely associated with MSt (p < 0.05. Comparisons between cardiorespiratory fitness quintiles showed higher medication consumption costs in seniors with lower aerobic endurance, as well as higher deterioration in MSt (p < 0.01. Conclusion: elderly people with better FF and, specifically, better cardiorespiratory fitness present lower medication consumption costs and a more positive MSt.

  10. Bateman gradients in hermaphrodites: An extended approach to quantify sexual selection.

    NARCIS (Netherlands)

    Anthes, N.; David, P.; Auld, J.R.; Hoffer, J.N.A.; Jarne, P.; Koene, J.M.; Kokko, H.; Lorenzi, M.C.; Pélissié, B.; Sprenger, D.; Staikou, A.; Schärer, L.

    2011-01-01

    Sexual selection is often quantified using Bateman gradients, which represent sex-specific regression slopes of reproductive success on mating success and thus describe the expected fitness returns from mating more often. Although the analytical framework for Bateman gradients aimed at covering all

  11. Sex-Specific Arrival Times on the Breeding Grounds: Hybridizing Migratory Skuas Provide Empirical Support for the Role of Sex Ratios.

    Science.gov (United States)

    Lisovski, Simeon; Fröhlich, Anne; von Tersch, Matthew; Klaassen, Marcel; Peter, Hans-Ulrich; Ritz, Markus S

    2016-04-01

    In migratory animals, protandry (earlier arrival of males on the breeding grounds) prevails over protogyny (females preceding males). In theory, sex differences in timing of arrival should be driven by the operational sex ratio, shifting toward protogyny in female-biased populations. However, empirical support for this hypothesis is, to date, lacking. To test this hypothesis, we analyzed arrival data from three populations of the long-distance migratory south polar skua (Catharacta maccormicki). These populations differed in their operational sex ratio caused by the unidirectional hybridization of male south polar skuas with female brown skuas (Catharacta antarctica lonnbergi). We found that arrival times were protandrous in allopatry, shifting toward protogyny in female-biased populations when breeding in sympatry. This unique observation is consistent with theoretical predictions that sex-specific arrival times should be influenced by sex ratio and that protogyny should be observed in populations with female-biased operational sex ratio.

  12. A sex-specific metabolite identified in a marine invertebrate utilizing phosphorus-31 nuclear magnetic resonance.

    Directory of Open Access Journals (Sweden)

    Robert A Kleps

    Full Text Available Hormone level differences are generally accepted as the primary cause for sexual dimorphism in animal and human development. Levels of low molecular weight metabolites also differ between men and women in circulating amino acids, lipids and carbohydrates and within brain tissue. While investigating the metabolism of blue crab tissues using Phosphorus-31 Nuclear Magnetic Resonance, we discovered that only the male blue crab (Callinectes sapidus contained a phosphorus compound with a chemical shift well separated from the expected phosphate compounds. Spectra obtained from male gills were readily differentiated from female gill spectra. Analysis from six years of data from male and female crabs documented that the sex-specificity of this metabolite was normal for this species. Microscopic analysis of male and female gills found no differences in their gill anatomy or the presence of parasites or bacteria that might produce this phosphorus compound. Analysis of a rare gynandromorph blue crab (laterally, half male and half female proved that this sex-specificity was an intrinsic biochemical process and was not caused by any variations in the diet or habitat of male versus female crabs. The existence of a sex-specific metabolite is a previously unrecognized, but potentially significant biochemical phenomenon. An entire enzyme system has been synthesized and activated only in one sex. Unless blue crabs are a unique species, sex-specific metabolites are likely to be present in other animals. Would the presence or absence of a sex-specific metabolite affect an animal's development, anatomy and biochemistry?

  13. Aging obviates sex-specific physiological responses to exercise.

    Science.gov (United States)

    Deschenes, Michael R; Taylor, Jessica L; Mangis, Katherine A

    2013-01-01

    Both sex and aging have been shown to affect physiological responses to exercise. The aim of the present investigation was to determine whether aging impacted the sex-specific nature of physiological responses to exercise commonly noted among young adults. Ten aged men (69.0 ± 1.7 years; mean ± SE) and 10 aged women (71.6 ± 1.3 years) reporting similar levels of habitual physical activity performed a 30-min exercise session at 60-65% of their predetermined peak oxygen uptake. Cardiovascular, thermoregulatory, and metabolic variables were assessed before exercise, at the 15th and 30th min of exercise, and at 5 and 15 min into a passive postexercise recovery period. Variables of interest were statistically analyzed via two-way analysis of variance with repeated measures; significance was set at P physiological variable of interest were identified, but not once was a significant effect of group (i.e., sex) detected. Exercise-induced physiological responses to prolonged, moderate intensity exercise were similar among aged men and aged women. This evidence that the sexually dimorphic nature of physiological responses to exercise is obviated with age should be taken into account when prescribing health-related exercise training programs for older individuals. Copyright © 2013 Wiley Periodicals, Inc.

  14. Allele-specific marker generation and linkage mapping on the Xiphophorus sex chromosomes.

    Science.gov (United States)

    Woolcock, B; Kazianis, S; Lucito, R; Walter, R B; Kallman, K D; Morizot, D C; Vielkind, J R

    2006-01-01

    There is great interest in the sex chromosomes of Xiphophorus fishes because both WY/YY and XX/XY sex-determining mechanisms function in these species, with at least one taxon possessing all three types of sex chromosomes, and because in certain interspecific hybrids melanoma arises as a consequence of inheritance of the sex-linked macromelanophore determining locus (MDL). Representational difference analysis (RDA) has been used to clone two sequences from the sex-determining region of X. maculatus, including a cholinergic receptor, nicotinic, delta polypeptide (CHRND) orthologue. Allele-specific assays for these sequences, as well as for the sex-linked XMRK1 and XMRK2 genes, were developed to distinguish W, X, and Y chromosomes derived from a X. maculatus (XX/XY) strain and a X. helleri (WY/YY) strain. Linkage mapping localized these markers to linkage group (LG) 24. No recombinants were observed between XMRK2 and MDL, confirming a role for XMRK2 in macromelanophore development. Although the master sex-determining (SD) locus certainly resides on Xiphophorus LG 24, autosomal loci are probably involved in sex determination as well, as indicated by the abnormal sex ratios in the backcross hybrids that contrast theoretical predictions based on LG 24 genotyping. Marker development and allelic discrimination on the Xiphophorus sex chromosomes should prove highly useful for studies that utilize this genus as an animal model.

  15. Evaluation of the Physiological Challenges in Extreme Environments: Implications for Enhanced Training, Operational Performance and Sex-Specific Responses

    Science.gov (United States)

    2017-10-01

    Operational Performance and Sex -Specific Responses PRINCIPAL INVESTIGATOR: Brent C. Ruby CONTRACTING ORGANIZATION: The University of Montana Missoula...Implications for Enhanced Training, Operational Performance and Sex -Specific Responses 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT...Evaluation of the physiological challenges in extreme environments: Implications for enhanced training, operational performance and sex -specific

  16. Sex-Specific Association between Metabolic Abnormalities and Elevated Alanine Aminotransferase Levels in a Military Cohort: The CHIEF Study

    Directory of Open Access Journals (Sweden)

    Kai-Wen Chen

    2018-03-01

    Full Text Available The association of metabolic syndrome (MetS components with elevated serum alanine aminotransferase (ALT levels, a marker of hepatic injury, may differ between men and women. However, the sex-specific association in a military young population which has a low prevalence of MetS was unclear. We conducted a cross-sectional examination in 6738 men and 766 women, aged 18–50 years, from the cardiorespiratory fitness study in armed forces (CHIEF in eastern Taiwan. The components of MetS were defined according to the updated International Diabetes Federation (IDF ethnic criteria for Asians. Elevated ALT levels were defined as ≥40 U/L for both sexes and ≥30 U/L for women alternatively. Multivariate logistic regression analysis was performed to determine the sex-specific association between MetS components and elevated ALT. The prevalence of MetS and elevated ALT in men were 11.9% and 12.7% respectively, and in women were 3.5%, and 3.8% respectively. In men, high-density lipoprotein < 40 mg/dL, blood pressures ≥ 130/85 mmHg, serum triglycerides ≥ 150 mg/dL, and waist size ≥ 90 cm were associated with elevated ALT (odds ratios (OR and 95% confidence intervals: 1.59 (1.34–1.90, 1.40 (1.19–1.65, 2.00 (1.68–2.39, and 1.68 (1.38–2.04; all p < 0.001; whereas in women, only fasting plasma glucose ≥ 100 mg/dL was associated with elevated ALT ≥ 40 U/L (OR: 7.59 (2.35–24.51, p = 0.001 and ALT ≥ 30 U/L (2.67 (0.89–7.95, p = 0.08. Our findings suggest that the relationship between metabolic abnormalities and elevated ALT may differ by sex, possibly due to the MetS more prevalent in young adult men than in women.

  17. The geography of sex-specific selection, local adaptation, and sexual dimorphism.

    Science.gov (United States)

    Connallon, Tim

    2015-09-01

    Local adaptation and sexual dimorphism are iconic evolutionary scenarios of intraspecific adaptive differentiation in the face of gene flow. Although theory has traditionally considered local adaptation and sexual dimorphism as conceptually distinct processes, emerging data suggest that they often act concurrently during evolutionary diversification. Here, I merge theories of local adaptation in space and sex-specific adaptation over time, and show that their confluence yields several new predictions about the roles of context-specific selection, migration, and genetic correlations, in adaptive diversification. I specifically revisit two influential predictions from classical studies of clinal adaptation and sexual dimorphism: (1) that local adaptation should decrease with distance from the species' range center and (2) that opposing directional selection between the sexes (sexual antagonism) should inevitably accompany the evolution of sexual dimorphism. I show that both predictions can break down under clinally varying selection. First, the geography of local adaptation can be sexually dimorphic, with locations of relatively high local adaptation differing profoundly between the sexes. Second, the intensity of sexual antagonism varies across the species' range, with subpopulations near the range center representing hotspots for antagonistic selection. The results highlight the context-dependent roles of migration versus sexual conflict as primary constraints to adaptive diversification. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  18. Cattle Sex-Specific Recombination and Genetic Control from a Large Pedigree Analysis.

    Science.gov (United States)

    Ma, Li; O'Connell, Jeffrey R; VanRaden, Paul M; Shen, Botong; Padhi, Abinash; Sun, Chuanyu; Bickhart, Derek M; Cole, John B; Null, Daniel J; Liu, George E; Da, Yang; Wiggans, George R

    2015-11-01

    Meiotic recombination is an essential biological process that generates genetic diversity and ensures proper segregation of chromosomes during meiosis. From a large USDA dairy cattle pedigree with over half a million genotyped animals, we extracted 186,927 three-generation families, identified over 8.5 million maternal and paternal recombination events, and constructed sex-specific recombination maps for 59,309 autosomal SNPs. The recombination map spans for 25.5 Morgans in males and 23.2 Morgans in females, for a total studied region of 2,516 Mb (986 kb/cM in males and 1,085 kb/cM in females). The male map is 10% longer than the female map and the sex difference is most pronounced in the subtelomeric regions. We identified 1,792 male and 1,885 female putative recombination hotspots, with 720 hotspots shared between sexes. These hotspots encompass 3% of the genome but account for 25% of the genome-wide recombination events in both sexes. During the past forty years, males showed a decreasing trend in recombination rate that coincided with the artificial selection for milk production. Sex-specific GWAS analyses identified PRDM9 and CPLX1 to have significant effects on genome-wide recombination rate in both sexes. Two novel loci, NEK9 and REC114, were associated with recombination rate in both sexes, whereas three loci, MSH4, SMC3 and CEP55, affected recombination rate in females only. Among the multiple PRDM9 paralogues on the bovine genome, our GWAS of recombination hotspot usage together with linkage analysis identified the PRDM9 paralogue on chromosome 1 to be associated in the U.S. Holstein data. Given the largest sample size ever reported for such studies, our results reveal new insights into the understanding of cattle and mammalian recombination.

  19. Radiation-induced bystander effects in vivo are sex specific

    International Nuclear Information System (INIS)

    Koturbash, Igor; Kutanzi, Kristy; Hendrickson, Karl; Rodriguez-Juarez, Rocio; Kogosov, Dmitry; Kovalchuk, Olga

    2008-01-01

    Ionizing radiation (IR) effects span beyond the area of direct exposure and can be observed in neighboring and distant naive cells and organs. This phenomenon is termed a 'bystander effect'. IR effects in directly exposed tissue in vivo are epigenetically mediated and distinct in males and females. Yet, IR-induced bystander effects have never been explored in a sex-specificity domain. We used an in vivo mouse model, whereby the bystander effects are studied in spleen of male and female animals subjected to head exposure when the rest of the body is protected by a medical-grade lead shield. We analyzed the induction of DNA damage and alterations in global DNA methylation. Molecular parameters were correlated with cellular proliferation and apoptosis levels. The changes observed in bystander organs are compared to the changes in unexposed animals and animals exposed to predicted and measured scatter doses. We have found the selective induction of DNA damage levels, global DNA methylation, cell proliferation and apoptosis in exposed and bystander spleen tissue of male and female mice. Sex differences were significantly diminished in animals subjected to a surgical removal of gonads. These data constitute the first evidence of sex differences in radiation-induced bystander effects in mouse spleen in vivo. We show the role of sex hormones in spleen bystander responses and discuss implications of the observed changes

  20. Radiation-induced bystander effects in vivo are sex specific

    Energy Technology Data Exchange (ETDEWEB)

    Koturbash, Igor; Kutanzi, Kristy; Hendrickson, Karl; Rodriguez-Juarez, Rocio; Kogosov, Dmitry [Department of Biological Sciences, University of Lethbridge, Alberta T1K 3M4 (Canada); Kovalchuk, Olga [Department of Biological Sciences, University of Lethbridge, Alberta T1K 3M4 (Canada)], E-mail: olga.kovalchuk@uleth.ca

    2008-07-03

    Ionizing radiation (IR) effects span beyond the area of direct exposure and can be observed in neighboring and distant naive cells and organs. This phenomenon is termed a 'bystander effect'. IR effects in directly exposed tissue in vivo are epigenetically mediated and distinct in males and females. Yet, IR-induced bystander effects have never been explored in a sex-specificity domain. We used an in vivo mouse model, whereby the bystander effects are studied in spleen of male and female animals subjected to head exposure when the rest of the body is protected by a medical-grade lead shield. We analyzed the induction of DNA damage and alterations in global DNA methylation. Molecular parameters were correlated with cellular proliferation and apoptosis levels. The changes observed in bystander organs are compared to the changes in unexposed animals and animals exposed to predicted and measured scatter doses. We have found the selective induction of DNA damage levels, global DNA methylation, cell proliferation and apoptosis in exposed and bystander spleen tissue of male and female mice. Sex differences were significantly diminished in animals subjected to a surgical removal of gonads. These data constitute the first evidence of sex differences in radiation-induced bystander effects in mouse spleen in vivo. We show the role of sex hormones in spleen bystander responses and discuss implications of the observed changes.

  1. Radiation-induced bystander effects in vivo are sex specific.

    Science.gov (United States)

    Koturbash, Igor; Kutanzi, Kristy; Hendrickson, Karl; Rodriguez-Juarez, Rocio; Kogosov, Dmitry; Kovalchuk, Olga

    2008-07-03

    Ionizing radiation (IR) effects span beyond the area of direct exposure and can be observed in neighboring and distant naïve cells and organs. This phenomenon is termed a 'bystander effect'. IR effects in directly exposed tissue in vivo are epigenetically mediated and distinct in males and females. Yet, IR-induced bystander effects have never been explored in a sex-specificity domain. We used an in vivo mouse model, whereby the bystander effects are studied in spleen of male and female animals subjected to head exposure when the rest of the body is protected by a medical-grade lead shield. We analyzed the induction of DNA damage and alterations in global DNA methylation. Molecular parameters were correlated with cellular proliferation and apoptosis levels. The changes observed in bystander organs are compared to the changes in unexposed animals and animals exposed to predicted and measured scatter doses. We have found the selective induction of DNA damage levels, global DNA methylation, cell proliferation and apoptosis in exposed and bystander spleen tissue of male and female mice. Sex differences were significantly diminished in animals subjected to a surgical removal of gonads. These data constitute the first evidence of sex differences in radiation-induced bystander effects in mouse spleen in vivo. We show the role of sex hormones in spleen bystander responses and discuss implications of the observed changes.

  2. Effects of sex and obesity on gait biomechanics before and six months after total knee arthroplasty: A longitudinal cohort study.

    Science.gov (United States)

    Paterson, K L; Sosdian, L; Hinman, R S; Wrigley, T V; Kasza, J; Dowsey, M; Choong, P; Bennell, K L

    2018-03-01

    Gait biomechanics, sex, and obesity can contribute to suboptimal outcomes from primary total knee arthroplasty. The aims of this study were to i) determine if sex and/or obesity influence the amount of change in gait biomechanics from pre-surgery to six months post-surgery and; ii) assess if gait returns to normal in men and women. Three-dimensional gait analysis was performed on 43 patients undergoing primary total knee arthroplasty for knee osteoarthritis (pre- and six months post-operative) and 40 asymptomatic controls. Mixed linear regression models were fit to assess which factors influenced change in gait biomechanics within the arthroplasty cohort, and interaction terms were included to assess if biomechanics returned to normal following surgery. Male peak knee adduction moment (p biomechanics after arthroplasty. Men retained abnormal gait patterns after surgery, whilst women did not. Further research should determine the long-term implications of gait abnormalities seen in men after arthroplasty. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Sex-specific mouse liver gene expression: genome-wide analysis of developmental changes from pre-pubertal period to young adulthood

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    Conforto Tara L

    2012-04-01

    Full Text Available Abstract Background Early liver development and the transcriptional transitions during hepatogenesis are well characterized. However, gene expression changes during the late postnatal/pre-pubertal to young adulthood period are less well understood, especially with regards to sex-specific gene expression. Methods Microarray analysis of male and female mouse liver was carried out at 3, 4, and 8 wk of age to elucidate developmental changes in gene expression from the late postnatal/pre-pubertal period to young adulthood. Results A large number of sex-biased and sex-independent genes showed significant changes during this developmental period. Notably, sex-independent genes involved in cell cycle, chromosome condensation, and DNA replication were down regulated from 3 wk to 8 wk, while genes associated with metal ion binding, ion transport and kinase activity were up regulated. A majority of genes showing sex differential expression in adult liver did not display sex differences prior to puberty, at which time extensive changes in sex-specific gene expression were seen, primarily in males. Thus, in male liver, 76% of male-specific genes were up regulated and 47% of female-specific genes were down regulated from 3 to 8 wk of age, whereas in female liver 67% of sex-specific genes showed no significant change in expression. In both sexes, genes up regulated from 3 to 8 wk were significantly enriched (p p Ihh; female-specific Cdx4, Cux2, Tox, and Trim24 and may contribute to the developmental changes that lead to global acquisition of liver sex-specificity by 8 wk of age. Conclusions Overall, the observed changes in gene expression during postnatal liver development reflect the deceleration of liver growth and the induction of specialized liver functions, with widespread changes in sex-specific gene expression primarily occurring in male liver.

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

    Science.gov (United States)

    Immler, Simone; Otto, Sarah Perin

    2015-03-01

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

  5. GenderMedDB: an interactive database of sex and gender-specific medical literature.

    Science.gov (United States)

    Oertelt-Prigione, Sabine; Gohlke, Björn-Oliver; Dunkel, Mathias; Preissner, Robert; Regitz-Zagrosek, Vera

    2014-01-01

    Searches for sex and gender-specific publications are complicated by the absence of a specific algorithm within search engines and by the lack of adequate archives to collect the retrieved results. We previously addressed this issue by initiating the first systematic archive of medical literature containing sex and/or gender-specific analyses. This initial collection has now been greatly enlarged and re-organized as a free user-friendly database with multiple functions: GenderMedDB (http://gendermeddb.charite.de). GenderMedDB retrieves the included publications from the PubMed database. Manuscripts containing sex and/or gender-specific analysis are continuously screened and the relevant findings organized systematically into disciplines and diseases. Publications are furthermore classified by research type, subject and participant numbers. More than 11,000 abstracts are currently included in the database, after screening more than 40,000 publications. The main functions of the database include searches by publication data or content analysis based on pre-defined classifications. In addition, registrants are enabled to upload relevant publications, access descriptive publication statistics and interact in an open user forum. Overall, GenderMedDB offers the advantages of a discipline-specific search engine as well as the functions of a participative tool for the gender medicine community.

  6. Targeting brain tumor cAMP: the case for sex-specific therapeutics

    Directory of Open Access Journals (Sweden)

    Nicole M Warrington

    2015-07-01

    Full Text Available A relationship between cyclic adenosine 3’, 5’-monophosphate (cAMP levels and brain tumor biology has been evident for nearly as long as cAMP and its synthetase, adenylate cyclase (ADCY have been known. The importance of the pathway in brain tumorigenesis has been demonstrated in vitro and in multiple animal models. Recently, we provided human validation for a cooperating oncogenic role for cAMP in brain tumorigenesis when we found that SNPs in ADCY8 were correlated with glioma (brain tumor risk in individuals with Neurofibromatosis type 1 (NF1. Together, these studies provide a strong rationale for targeting cAMP in brain tumor therapy. However, the cAMP pathway is well known to be sexually dimorphic, and SNPs in ADCY8 affected glioma risk in a sex-specific fashion, elevating the risk for females while protecting males. The cAMP pathway can be targeted at multiple levels in the regulation of its synthesis and degradation. Sex differences in response to drugs that target cAMP regulators indicate that successful targeting of the cAMP pathway for brain tumor patients is likely to require matching specific mechanisms of drug action with patient sex.

  7. The evolution of sexes: A specific test of the disruptive selection theory.

    Science.gov (United States)

    da Silva, Jack

    2018-01-01

    The disruptive selection theory of the evolution of anisogamy posits that the evolution of a larger body or greater organismal complexity selects for a larger zygote, which in turn selects for larger gametes. This may provide the opportunity for one mating type to produce more numerous, small gametes, forcing the other mating type to produce fewer, large gametes. Predictions common to this and related theories have been partially upheld. Here, a prediction specific to the disruptive selection theory is derived from a previously published game-theoretic model that represents the most complete description of the theory. The prediction, that the ratio of macrogamete to microgamete size should be above three for anisogamous species, is supported for the volvocine algae. A fully population genetic implementation of the model, involving mutation, genetic drift, and selection, is used to verify the game-theoretic approach and accurately simulates the evolution of gamete sizes in anisogamous species. This model was extended to include a locus for gamete motility and shows that oogamy should evolve whenever there is costly motility. The classic twofold cost of sex may be derived from the fitness functions of these models, showing that this cost is ultimately due to genetic conflict.

  8. Fungal Infection Induces Sex-Specific Transcriptional Changes and Alters Sexual Dimorphism in the Dioecious Plant Silene latifolia.

    Directory of Open Access Journals (Sweden)

    Niklaus Zemp

    2015-10-01

    Full Text Available Sexual dimorphism, including differences in morphology, behavior and physiology between females and males, is widespread in animals and plants and is shaped by gene expression differences between the sexes. Such expression differences may also underlie sex-specific responses of hosts to pathogen infections, most notably when pathogens induce partial sex reversal in infected hosts. The genetic changes associated with sex-specific responses to pathogen infections on the one hand, and sexual dimorphism on the other hand, remain poorly understood. The dioecious White Campion (Silene latifolia displays sexual dimorphism in floral traits and infection with the smut fungus Micobrotryum lychnidis-dioicae induces a partial sex reversal in females. We find strong sex-specific responses to pathogen infection and reduced sexual dimorphism in infected S. latifolia. This provides a direct link between pathogen-mediated changes in sex-biased gene expression and altered sexual dimorphism in the host. Expression changes following infection affected mainly genes with male-biased expression in healthy plants. In females, these genes were up-regulated, leading to a masculinization of the transcriptome. In contrast, infection in males was associated with down-regulation of these genes, leading to a demasculinization of the transcriptome. To a lesser extent, genes with female-biased expression in healthy plants were also affected in opposite directions in the two sexes. These genes were overall down-regulated in females and up-regulated in males, causing, respectively, a defeminization in infected females and a feminization of the transcriptome in infected males. Our results reveal strong sex-specific responses to pathogen infection in a dioecious plant and provide a link between pathogen-induced changes in sex-biased gene expression and sexual dimorphism.

  9. Fungal Infection Induces Sex-Specific Transcriptional Changes and Alters Sexual Dimorphism in the Dioecious Plant Silene latifolia.

    Science.gov (United States)

    Zemp, Niklaus; Tavares, Raquel; Widmer, Alex

    2015-10-01

    Sexual dimorphism, including differences in morphology, behavior and physiology between females and males, is widespread in animals and plants and is shaped by gene expression differences between the sexes. Such expression differences may also underlie sex-specific responses of hosts to pathogen infections, most notably when pathogens induce partial sex reversal in infected hosts. The genetic changes associated with sex-specific responses to pathogen infections on the one hand, and sexual dimorphism on the other hand, remain poorly understood. The dioecious White Campion (Silene latifolia) displays sexual dimorphism in floral traits and infection with the smut fungus Micobrotryum lychnidis-dioicae induces a partial sex reversal in females. We find strong sex-specific responses to pathogen infection and reduced sexual dimorphism in infected S. latifolia. This provides a direct link between pathogen-mediated changes in sex-biased gene expression and altered sexual dimorphism in the host. Expression changes following infection affected mainly genes with male-biased expression in healthy plants. In females, these genes were up-regulated, leading to a masculinization of the transcriptome. In contrast, infection in males was associated with down-regulation of these genes, leading to a demasculinization of the transcriptome. To a lesser extent, genes with female-biased expression in healthy plants were also affected in opposite directions in the two sexes. These genes were overall down-regulated in females and up-regulated in males, causing, respectively, a defeminization in infected females and a feminization of the transcriptome in infected males. Our results reveal strong sex-specific responses to pathogen infection in a dioecious plant and provide a link between pathogen-induced changes in sex-biased gene expression and sexual dimorphism.

  10. Obesity and Aerobic Fitness among Urban Public School Students in Elementary, Middle, and High School.

    Directory of Open Access Journals (Sweden)

    B Ruth Clark

    Full Text Available To assess the prevalence of cardiovascular disease risk among urban public school students through a collaborative school district and university partnership.Children and adolescents in grades K-12 from 24 urban public schools participated in measurements of height, weight, and other health metrics during the 2009-2010 school year. Body mass index (BMI percentiles and z-scores were computed for 4673 students. President's Challenge 1-mile endurance run was completed by 1075 students ages 9-19 years. Maximal oxygen consumption (⩒O2max was predicted using an age-, sex-, and BMI-specific formula to determine health-related fitness. Resting blood pressure (BP was assessed in 1467 students. Regression analyses were used to compare BMI z-scores, fitness, and age- and sex-specific BP percentiles across grade levels. Chi-square tests were used to explore the effect of sex and grade-level on health-related outcomes.Based on BMI, 19.8% were categorized as overweight and 24.4% were obese. Included in the obese category were 454 students (9.7% of sample classified with severe obesity. Using FITNESSGRAM criteria, 50.2% of students did not achieve the Healthy Fitness Zone (HFZ; the proportion of students in the Needs Improvement categories increased from elementary to middle school to high school. Male students demonstrated higher fitness than female students, with 61.4% of boys and only 35.4% of girls meeting HFZ standards. Elevated BP was observed among 24% of 1467 students assessed. Systolic and diastolic BP z-scores revealed low correlation with BMI z-scores.A community-university collaboration identified obesity, severe obesity, overweight, and low aerobic fitness to be common risk factors among urban public school students.

  11. Aerobic fitness is associated with greater hippocampal cerebral blood flow in children

    Directory of Open Access Journals (Sweden)

    Laura Chaddock-Heyman

    2016-08-01

    Full Text Available The present study is the first to investigate whether cerebral blood flow in the hippocampus relates to aerobic fitness in children. In particular, we used arterial spin labeling (ASL perfusion MRI to provide a quantitative measure of blood flow in the hippocampus in 73 7- to 9-year-old preadolescent children. Indeed, aerobic fitness was found to relate to greater perfusion in the hippocampus, independent of age, sex, and hippocampal volume. Such results suggest improved microcirculation and cerebral vasculature in preadolescent children with higher levels of aerobic fitness. Further, aerobic fitness may influence how the brain regulates its metabolic demands via blood flow in a region of the brain important for learning and memory. To add specificity to the relationship of fitness to the hippocampus, we demonstrate no significant association between aerobic fitness and cerebral blood flow in the brainstem. Our results reinforce the importance of aerobic fitness during a critical period of child development.

  12. Sex Education Targeting African Communities in the United Kingdom: Is It Fit for Purpose?

    Science.gov (United States)

    Schmidt, E.; Olomo, F.; Corcoran, N.

    2012-01-01

    This study addresses the issue of the sexual needs of ethnic minority groups in the UK. Using focus group discussions with health service users and third-sector providers, it explores the perception of sex education by Black African communities living in a culturally diverse area in East London, focusing specifically on participants' understanding…

  13. A dense SNP-based linkage map for Atlantic salmon (Salmo salar reveals extended chromosome homeologies and striking differences in sex-specific recombination patterns

    Directory of Open Access Journals (Sweden)

    Lien Sigbjørn

    2011-12-01

    Full Text Available Abstract Background The Atlantic salmon genome is in the process of returning to a diploid state after undergoing a whole genome duplication (WGD event between 25 and100 million years ago. Existing data on the proportion of paralogous sequence variants (PSVs, multisite variants (MSVs and other types of complex sequence variation suggest that the rediplodization phase is far from over. The aims of this study were to construct a high density linkage map for Atlantic salmon, to characterize the extent of rediploidization and to improve our understanding of genetic differences between sexes in this species. Results A linkage map for Atlantic salmon comprising 29 chromosomes and 5650 single nucleotide polymorphisms (SNPs was constructed using genotyping data from 3297 fish belonging to 143 families. Of these, 2696 SNPs were generated from ESTs or other gene associated sequences. Homeologous chromosomal regions were identified through the mapping of duplicated SNPs and through the investigation of syntenic relationships between Atlantic salmon and the reference genome sequence of the threespine stickleback (Gasterosteus aculeatus. The sex-specific linkage maps spanned a total of 2402.3 cM in females and 1746.2 cM in males, highlighting a difference in sex specific recombination rate (1.38:1 which is much lower than previously reported in Atlantic salmon. The sexes, however, displayed striking differences in the distribution of recombination sites within linkage groups, with males showing recombination strongly localized to telomeres. Conclusion The map presented here represents a valuable resource for addressing important questions of interest to evolution (the process of re-diploidization, aquaculture and salmonid life history biology and not least as a resource to aid the assembly of the forthcoming Atlantic salmon reference genome sequence.

  14. Sex chromosome repeats tip the balance towards speciation.

    Science.gov (United States)

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

    2018-04-06

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

  15. Anonymous sex and HIV risk practices among men using the Internet specifically to find male partners for unprotected sex.

    Science.gov (United States)

    Klein, H

    2012-06-01

    To examine the popularity of anonymous sex practices among men using the Internet to find male partners for unprotected sex, and how anonymous sex relates to involvement in other HIV-related risk behaviours, and to investigate the factors associated with engaging in anonymous sex. Structured telephone interviews were conducted with men who used the Internet specifically to find male partners for unprotected sex. Random sampling from 16 websites was used to obtain a national sample. The data reported in this paper were based on quantitative interviews collected with a cross-sectional study design. Between January 2008 and May 2009, confidential telephone interviews lasting approximately 1-2 h were completed with 332 men. Participants were paid $35 for their participation. Most of the men (67.4%) liked anonymous sex, and slightly more than half (51.2%) had engaged in the behaviour during the month prior to interview. Involvement in anonymous sex was associated with greater involvement in a variety of human immunodeficiency virus (HIV)-related risk practices, such as illegal drug use, number of sex partners, and amount of unprotected sex. Four factors were associated with having vs not having anonymous sex: (1) being HIV positive; (2) answering all of the HIV-related knowledge questions correctly; (3) deriving greater enjoyment from having sex in public places, such as parks, public toilets, or adult book shops; and (4) greater impulsivity. Seven factors were associated with greater vs lesser involvement in anonymous sex among those practising the behaviour: (1) being involved in a relationship with a long-term partner; (2) liking to have sex in public places; (3) using bareback-oriented websites to identify sex partners; (4) greater impulsivity; (5) low level of condom use self-efficacy; (6) greater knowledge about HIV/acquired immunodeficiency syndrome; and either (7a) severe childhood maltreatment or (7b) Caucasian race. Men in this population often sought

  16. A single sex pheromone receptor determines chemical response specificity of sexual behavior in the silkmoth Bombyx mori.

    Science.gov (United States)

    Sakurai, Takeshi; Mitsuno, Hidefumi; Haupt, Stephan Shuichi; Uchino, Keiro; Yokohari, Fumio; Nishioka, Takaaki; Kobayashi, Isao; Sezutsu, Hideki; Tamura, Toshiki; Kanzaki, Ryohei

    2011-06-01

    In insects and other animals, intraspecific communication between individuals of the opposite sex is mediated in part by chemical signals called sex pheromones. In most moth species, male moths rely heavily on species-specific sex pheromones emitted by female moths to identify and orient towards an appropriate mating partner among a large number of sympatric insect species. The silkmoth, Bombyx mori, utilizes the simplest possible pheromone system, in which a single pheromone component, (E, Z)-10,12-hexadecadienol (bombykol), is sufficient to elicit full sexual behavior. We have previously shown that the sex pheromone receptor BmOR1 mediates specific detection of bombykol in the antennae of male silkmoths. However, it is unclear whether the sex pheromone receptor is the minimally sufficient determination factor that triggers initiation of orientation behavior towards a potential mate. Using transgenic silkmoths expressing the sex pheromone receptor PxOR1 of the diamondback moth Plutella xylostella in BmOR1-expressing neurons, we show that the selectivity of the sex pheromone receptor determines the chemical response specificity of sexual behavior in the silkmoth. Bombykol receptor neurons expressing PxOR1 responded to its specific ligand, (Z)-11-hexadecenal (Z11-16:Ald), in a dose-dependent manner. Male moths expressing PxOR1 exhibited typical pheromone orientation behavior and copulation attempts in response to Z11-16:Ald and to females of P. xylostella. Transformation of the bombykol receptor neurons had no effect on their projections in the antennal lobe. These results indicate that activation of bombykol receptor neurons alone is sufficient to trigger full sexual behavior. Thus, a single gene defines behavioral selectivity in sex pheromone communication in the silkmoth. Our findings show that a single molecular determinant can not only function as a modulator of behavior but also as an all-or-nothing initiator of a complex species-specific behavioral sequence.

  17. A single sex pheromone receptor determines chemical response specificity of sexual behavior in the silkmoth Bombyx mori.

    Directory of Open Access Journals (Sweden)

    Takeshi Sakurai

    2011-06-01

    Full Text Available In insects and other animals, intraspecific communication between individuals of the opposite sex is mediated in part by chemical signals called sex pheromones. In most moth species, male moths rely heavily on species-specific sex pheromones emitted by female moths to identify and orient towards an appropriate mating partner among a large number of sympatric insect species. The silkmoth, Bombyx mori, utilizes the simplest possible pheromone system, in which a single pheromone component, (E, Z-10,12-hexadecadienol (bombykol, is sufficient to elicit full sexual behavior. We have previously shown that the sex pheromone receptor BmOR1 mediates specific detection of bombykol in the antennae of male silkmoths. However, it is unclear whether the sex pheromone receptor is the minimally sufficient determination factor that triggers initiation of orientation behavior towards a potential mate. Using transgenic silkmoths expressing the sex pheromone receptor PxOR1 of the diamondback moth Plutella xylostella in BmOR1-expressing neurons, we show that the selectivity of the sex pheromone receptor determines the chemical response specificity of sexual behavior in the silkmoth. Bombykol receptor neurons expressing PxOR1 responded to its specific ligand, (Z-11-hexadecenal (Z11-16:Ald, in a dose-dependent manner. Male moths expressing PxOR1 exhibited typical pheromone orientation behavior and copulation attempts in response to Z11-16:Ald and to females of P. xylostella. Transformation of the bombykol receptor neurons had no effect on their projections in the antennal lobe. These results indicate that activation of bombykol receptor neurons alone is sufficient to trigger full sexual behavior. Thus, a single gene defines behavioral selectivity in sex pheromone communication in the silkmoth. Our findings show that a single molecular determinant can not only function as a modulator of behavior but also as an all-or-nothing initiator of a complex species-specific

  18. Return to Work After Acute Myocardial Infarction: Comparison Between Young Women and Men.

    Science.gov (United States)

    Dreyer, Rachel P; Xu, Xiao; Zhang, Weiwei; Du, Xue; Strait, Kelly M; Bierlein, Maggie; Bucholz, Emily M; Geda, Mary; Fox, James; D'Onofrio, Gail; Lichtman, Judith H; Bueno, Héctor; Spertus, John A; Krumholz, Harlan M

    2016-02-01

    Return to work after acute myocardial infarction (AMI) is an important outcome and is particularly relevant to young patients. Women may be at a greater risk for not returning to work given evidence of their worse recovery after AMI than similarly aged men. However, sex differences in return to work after AMI has not been studied extensively in a young population (≤ 55 years). We analyzed data from 1680 patients with AMI aged 18 to 55 years (57% women) participating in the Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients (VIRGO) study who were working full time (≥ 35 hours) before the event. Data were obtained by medical record abstraction and patient interviews. We conducted multivariable regression analyses to examine sex differences in return to work at 12 months after AMI, and the association of patient characteristics with return to work. When compared with young men, young women were less likely to return to work (89% versus 85%; 85% versus 89%, P=0.02); however, this sex difference was not significant after adjusting for patient sociodemographic characteristics, psychosocial factors, and health measures. Being married, engaging in a professional or clerical type of work, having more favorable physical health, and having no previous coronary disease or hypertension were significantly associated with a higher likelihood of return to work at 12 months. Among a young population, women are less likely to return to work after AMI than men. This disadvantage is explained by differences in demographic, occupational, and health characteristics. © 2016 American Heart Association, Inc.

  19. Return to the Workforce After First Hospitalization for Heart Failure

    DEFF Research Database (Denmark)

    Rørth, Rasmus; Wong, Chih; Kragholm, Kristian

    2016-01-01

    Background: Return to work is important financially, as a marker of functional status and for self-esteem in patients developing chronic illness. We examined return to work after first heart failure (HF) hospitalization. Methods: By individual-level linkage of nationwide Danish registries, we...... with lower chance of return to work. Conclusions: Patients in the workforce before HF hospitalization had low mortality but high risk of detachment from the workforce 1 year later. Young age, male sex, and a higher level of education were predictors of return to work....

  20. Sex-specific differences in injury types among basketball players

    Directory of Open Access Journals (Sweden)

    Ito E

    2014-12-01

    Full Text Available Eri Ito, Jun Iwamoto, Koichiro Azuma, Hideo MatsumotoInstitute for Integrated Sports Medicine, Keio University School of Medicine, Tokyo, JapanAbstract: The purpose of the present study was to investigate sex-specific differences in injury types among basketball players. According to our database, during the 20-year period between October 1991 and June 2011, 1,219 basketball players (640 males and 579 females consulted our sports medicine clinic; in total, 1,414 injuries in basketball players (729 injuries in males and 685 injuries in females were recorded. The mean age of patients was 19.6 years. The most common injury site was the knee, followed by the foot and ankle, lower back, and upper extremities. There was a higher proportion of female players presenting with a knee injury, compared with male players (50.4% vs 41.7%, and a lower proportion of female players presenting with an upper extremity injury (5.1% vs 9.7%. The proportion of anterior cruciate ligament injury in the 10–19-year-old age group was higher among female players than among male players (45.9% vs 22.1%, while the proportions of Osgood–Schlatter disease in the 10–19-year-old age group and jumper's knee (patellar and femoral tendinopathy in the 20–29-year-old age group were higher among male players than among female players (12.5% vs 1.8% and 14.6% vs 3.7%, respectively. However, the proportions of other injuries did not differ significantly between male and female players. The present observational study, which was performed using a retrospective case-series design, showed the existence of sex-specific differences in knee injuries sustained while participating in basketball.Keywords: sports injury, sex, anterior cruciate ligament injury, Osgood–Schlatter disease, basketball

  1. Global, regional, and national age–sex specific all-cause and cause-specific mortality for 240 causes of death, 1990–2013

    DEFF Research Database (Denmark)

    Peterson, Carrie Beth

    2015-01-01

    BACKGROUND: Up-to-date evidence on levels and trends for age-sex-specific all-cause and cause-specific mortality is essential for the formation of global, regional, and national health policies. In the Global Burden of Disease Study 2013 (GBD 2013) we estimated yearly deaths for 188 countries...... between 1990, and 2013. We used the results to assess whether there is epidemiological convergence across countries. METHODS: We estimated age-sex-specific all-cause mortality using the GBD 2010 methods with some refinements to improve accuracy applied to an updated database of vital registration, survey...... informed by meta-regression of prevalence studies. For pathogen-specific causes of diarrhoea and lower respiratory infections we used a counterfactual approach. We computed two measures of convergence (inequality) across countries: the average relative difference across all pairs of countries (Gini...

  2. Global, regional, and national age–sex specific all-cause and cause-specific mortality for 240 causes of death, 1990–2013

    DEFF Research Database (Denmark)

    Moesgaard Iburg, Kim

    2015-01-01

    Background Up-to-date evidence on levels and trends for age-sex-specific all-cause and cause-specific mortality is essential for the formation of global, regional, and national health policies. In the Global Burden of Disease Study 2013 (GBD 2013) we estimated yearly deaths for 188 countries...... between 1990, and 2013. We used the results to assess whether there is epidemiological convergence across countries. Methods We estimated age-sex-specific all-cause mortality using the GBD 2010 methods with some refinements to improve accuracy applied to an updated database of vital registration, survey...... informed by meta-regression of prevalence studies. For pathogen-specific causes of diarrhoea and lower respiratory infections we used a counterfactual approach. We computed two measures of convergence (inequality) across countries: the average relative difference across all pairs of countries (Gini...

  3. Stressor-specific effects of sex on HPA axis hormones and activation of stress-related neurocircuitry.

    Science.gov (United States)

    Babb, Jessica A; Masini, Cher V; Day, Heidi E W; Campeau, Serge

    2013-11-01

    Experiencing stress can be physically and psychologically debilitating to an organism. Women have a higher prevalence of some stress-related mental illnesses, the reasons for which are unknown. These experiments explore differential HPA axis hormone release in male and female rats following acute stress. Female rats had a similar threshold of HPA axis hormone release following low intensity noise stress as male rats. Sex did not affect the acute release, or the return of HPA axis hormones to baseline following moderate intensity noise stress. Sensitive indices of auditory functioning obtained by modulation of the acoustic startle reflex by weak pre-pulses did not reveal any sexual dimorphism. Furthermore, male and female rats exhibited similar c-fos mRNA expression in the brain following noise stress, including several sex-influenced stress-related regions. The HPA axis response to noise stress was not affected by stage of estrous cycle, and ovariectomy significantly increased hormone release. Direct comparison of HPA axis hormone release to two different stressors in the same animals revealed that although female rats exhibit robustly higher HPA axis hormone release after restraint stress, the same effect was not observed following moderate and high intensity loud noise stress. Finally, the differential effect of sex on HPA axis responses to noise and restraint stress cannot readily be explained by differential social cues or general pain processing. These studies suggest the effect of sex on acute stress-induced HPA axis hormone activity is highly dependent on the type of stressor.

  4. Sex-specific weight loss mediates sexual size dimorphism in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Nicholas D Testa

    Full Text Available The selective pressures leading to the evolution of Sexual Size Dimorphism (SSD have been well studied in many organisms, yet, the underlying developmental mechanisms are poorly understood. By generating a complete growth profile by sex in Drosophila melanogaster, we describe the sex-specific pattern of growth responsible for SSD. Growth rate and critical size for pupariation significantly contributed to adult SSD, whereas duration of growth did not. Surprisingly, SSD at peak larval mass was twice that of the uneclosed adult SSD with weight loss between peak larval mass and pupariation playing an important role in generating the final SSD. Our finding that weight loss is an important regulator of SSD adds additional complexity to our understanding of how body size is regulated in different sexes. Collectively, these data allow for the elucidation of the molecular-genetic mechanisms that generate SSD, an important component of understanding how SSD evolves.

  5. Sex differences in the vaccine-specific and non-targeted effects of vaccines

    DEFF Research Database (Denmark)

    Flanagan, Katie L; Klein, Sabra L; Skakkebaek, Niels E

    2011-01-01

    Vaccines have non-specific effects (NSE) on subsequent morbidity and mortality from non-vaccine related infectious diseases. Thus NSE refers to any effect that cannot be accounted for by the induction of immunity against the vaccine-targeted disease. These effects are sex-differential, generally...... being more pronounced in females than males. Furthermore, the NSE are substantial causing greater than fifty percent changes in all cause mortality in certain settings, yet have never been systematically tested despite the fact that millions of children receive vaccines each year. As we strive...... to eliminate infectious diseases through vaccination programmes, the relative impact of NSE of vaccines on mortality is likely to increase, raising important questions regarding the future of certain vaccine schedules. A diverse group of scientists met in Copenhagen to discuss non-specific and sex...

  6. Association Between CNDP1 Genotype and Diabetic Nephropathy Is Sex Specific

    NARCIS (Netherlands)

    Mooyaart, Antien L.; Zutinic, Ana; Bakker, Stephan J. L.; Grootendorst, Diana C.; Kleefstra, Nanne; van Valkengoed, Irene G. M.; Bohringer, Stefan; Bilo, Henk J. G.; Dekker, Friedo W.; Bruijn, Jan Anthonie; Navis, Gerjan; Janssen, Bart; Baelde, Hans J.; De Heer, Emile

    OBJECTIVE-The 5-5 homozygous CNDP1 (carnosinase) genotype is associated with a reduced risk of diabetic nephropathy. We investigated whether this association is sex specific and independent of susceptibility for type 2 diabetes. RESEARCH DESIGN AND METHODS-Three separate groups of 114, 90, and 66

  7. Depleted uranium induces sex- and tissue-specific methylation patterns in adult zebrafish

    International Nuclear Information System (INIS)

    Gombeau, Kewin; Pereira, Sandrine; Ravanat, Jean-Luc; Camilleri, Virginie; Cavalie, Isabelle; Bourdineaud, Jean-Paul; Adam-Guillermin, Christelle

    2016-01-01

    We examined the effects of chronic exposure to different concentrations (2 and 20 μg L"−"1) of environmentally relevant waterborne depleted uranium (DU) on the DNA methylation patterns both at HpaII restriction sites (5′-CCGG-3′) and across the whole genome in the zebrafish brain, gonads, and eyes. We first identified sex-dependent differences in the methylation level of HpaII sites after exposure. In males, these effects were present as early as 7 days after exposure to 20 μg L"−"1 DU, and were even more pronounced in the brain, gonads, and eyes after 24 days. However, in females, hypomethylation was only observed in the gonads after exposure to 20 μg L"−"1 DU for 24 days. Sex-specific effects of DU were also apparent at the whole-genome level, because in males, exposure to 20 μg L"−"1 DU for 24 days resulted in cytosine hypermethylation in the brain and eyes and hypomethylation in the gonads. In contrast, in females, hypermethylation was observed in the brain after exposure to both concentrations of DU for 7 days. Based on our current knowledge of uranium toxicity, several hypotheses are proposed to explain these findings, including the involvement of oxidative stress, alteration of demethylation enzymes and the calcium signaling pathway. This study reports, for the first time, the sex- and tissue-specific epigenetic changes that occur in a nonhuman organism after exposure to environmentally relevant concentrations of uranium, which could induce transgenerational epigenetic effects. - Highlights: • This study demonstrates a sex-related effect of DU exposure on DNA methylation patterns. • Impacts on DNA methylation patterns revealed a tissue-specific effect of DU exposure. • The MS–AFLP and HPLC–MS/MS sensitively and complementarily demonstrated the responses to environmental concentrations of DU.

  8. Sex-specific signaling in the blood-brain barrier is required for male courtship in Drosophila.

    Directory of Open Access Journals (Sweden)

    Valbona Hoxha

    Full Text Available Soluble circulating proteins play an important role in the regulation of mating behavior in Drosophila melanogaster. However, how these factors signal through the blood-brain barrier (bbb to interact with the sex-specific brain circuits that control courtship is unknown. Here we show that male identity of the blood-brain barrier is necessary and that male-specific factors in the bbb are physiologically required for normal male courtship behavior. Feminization of the bbb of adult males significantly reduces male courtship. We show that the bbb-specific G-protein coupled receptor moody and bbb-specific Go signaling in adult males are necessary for normal courtship. These data identify sex-specific factors and signaling processes in the bbb as important regulators of male mating behavior.

  9. Knee joint biomechanics and neuromuscular control during gait before and after total knee arthroplasty are sex-specific.

    Science.gov (United States)

    Astephen Wilson, Janie L; Dunbar, Michael J; Hubley-Kozey, Cheryl L

    2015-01-01

    The future of total knee arthroplasty (TKA) surgery will involve planning that incorporates more patient-specific characteristics. Despite known biological, morphological, and functional differences between men and women, there has been little investigation into knee joint biomechanical and neuromuscular differences between men and women with osteoarthritis, and none that have examined sex-specific biomechanical and neuromuscular responses to TKA surgery. The objective of this study was to examine sex-associated differences in knee kinematics, kinetics and neuromuscular patterns during gait before and after TKA. Fifty-two patients with end-stage knee OA (28 women, 24 men) underwent gait and neuromuscular analysis within the week prior to and one year after surgery. A number of sex-specific differences were identified which suggest a different manifestation of end-stage knee OA between the sexes. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Sex-specific differences in injury types among basketball players

    OpenAIRE

    Ito E; Iwamoto J; Azuma K; Matsumoto H

    2014-01-01

    Eri Ito, Jun Iwamoto, Koichiro Azuma, Hideo MatsumotoInstitute for Integrated Sports Medicine, Keio University School of Medicine, Tokyo, JapanAbstract: The purpose of the present study was to investigate sex-specific differences in injury types among basketball players. According to our database, during the 20-year period between October 1991 and June 2011, 1,219 basketball players (640 males and 579 females) consulted our sports medicine clinic; in total, 1,414 injuries in basketball player...

  11. Development of a PubMed Based Search Tool for Identifying Sex and Gender Specific Health Literature.

    Science.gov (United States)

    Song, Michael M; Simonsen, Cheryl K; Wilson, Joanna D; Jenkins, Marjorie R

    2016-02-01

    An effective literature search strategy is critical to achieving the aims of Sex and Gender Specific Health (SGSH): to understand sex and gender differences through research and to effectively incorporate the new knowledge into the clinical decision making process to benefit both male and female patients. The goal of this project was to develop and validate an SGSH literature search tool that is readily and freely available to clinical researchers and practitioners. PubMed, a freely available search engine for the Medline database, was selected as the platform to build the SGSH literature search tool. Combinations of Medical Subject Heading terms, text words, and title words were evaluated for optimal specificity and sensitivity. The search tool was then validated against reference bases compiled for two disease states, diabetes and stroke. Key sex and gender terms and limits were bundled to create a search tool to facilitate PubMed SGSH literature searches. During validation, the search tool retrieved 50 of 94 (53.2%) stroke and 62 of 95 (65.3%) diabetes reference articles selected for validation. A general keyword search of stroke or diabetes combined with sex difference retrieved 33 of 94 (35.1%) stroke and 22 of 95 (23.2%) diabetes reference base articles, with lower sensitivity and specificity for SGSH content. The Texas Tech University Health Sciences Center SGSH PubMed Search Tool provides higher sensitivity and specificity to sex and gender specific health literature. The tool will facilitate research, clinical decision-making, and guideline development relevant to SGSH.

  12. Intention of mountain bikers to return | Kruger | South African Journal ...

    African Journals Online (AJOL)

    These were enjoyment, health and fitness, event status and team, social interaction, relaxation, and dedication. Participants in the two events significantly differed based on the importance of the motives. The motives dedication, enjoyment, and health and fitness were identified as drivers of intention for return participation.

  13. Direct and indirect genetic effects of sex-specific mitonuclear epistasis on reproductive ageing

    DEFF Research Database (Denmark)

    Immonen, Elina; Collet, Marie; Goenaga, Julieta

    2016-01-01

    Mitochondria are involved in ageing and their function requires coordinated action of both mitochondrial and nuclear genes. Epistasis between the two genomes can influence lifespan but whether this also holds for reproductive senescence is unclear. Maternal inheritance of mitochondria predicts sex...... to slower senescence relative to novel mitonuclear combinations. We found no evidence for mitonuclear coadaptation in males. Mitonuclear epistasis not only affected age-specific ejaculate weight, but also influenced male age-dependent indirect effects on traits expressed by their female partners (fecundity...... beetle Callosobruchus maculatus, using introgression lines harbouring distinct mitonuclear genotypes. Our results reveal both direct and indirect sex-specific effects of mitonuclear epistasis on reproductive ageing. Females harbouring coadapted mitonuclear genotypes showed higher lifetime fecundity due...

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

    Science.gov (United States)

    Gerdes, Eugenia Proctor; Husted, Victoria L.

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

  15. Vasopressin regulates social recognition in juvenile and adult rats of both sexes, but in sex- and age-specific ways.

    Science.gov (United States)

    Veenema, A H; Bredewold, R; De Vries, G J

    2012-01-01

    In adult male rats, vasopressin (AVP) facilitates social recognition via activation of V1a receptors within the lateral septum. Much less is known about how AVP affects social recognition in adult females or in juvenile animals of either sex. We found that administration of the specific V1a receptor antagonist d(CH(2))(5)[Tyr(Me)(2)]AVP into the lateral septum of adult rats impaired, whereas AVP extended, social discrimination in both sexes. In juveniles, however, we detected a sex difference, such that males but not females showed social discrimination. Interestingly, administration of the V1a receptor antagonist to juveniles (either intracerebroventricularly or locally in the lateral septum) did not prevent social discrimination, but instead significantly decreased the investigation of a novel as opposed to a familiar animal in both sexes, with stronger effects in males. V1a receptors were found to be abundantly expressed in the lateral septum with higher binding density in females than in males. These findings demonstrate that activation of V1a receptors in the lateral septum is important for social recognition in both sexes, and that the roles of septal V1a receptors in social recognition change during development. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. Youth's perceptions of HIV infection risk: a sex-specific test of two ...

    African Journals Online (AJOL)

    Youth's perceptions of HIV infection risk: a sex-specific test of two risk models. ... The analysis is based on data from the 2003 Demographic and Health survey ... multiple partners, Nigeria, risk perception, sexual behaviour, vulnerability to HIV ...

  17. Is the Veterans Specific Activity Questionnaire Valid to Assess Older Adults Aerobic Fitness?

    Science.gov (United States)

    de Carvalho Bastone, Alessandra; de Souza Moreira, Bruno; Teixeira, Claudine Patrícia; Dias, João Marcos Domingues; Dias, Rosângela Corrêa

    2016-01-01

    Aerobic fitness in older adults is related to health status, incident disability, nursing home admission, and all-cause mortality. The most accurate quantification of aerobic fitness, expressed as peak oxygen consumption in mL·kg·min, is the cardiorespiratory exercise test; however, it is not feasible in all settings and might offer risk to patients. The Veterans Specific Activity Questionnaire (VSAQ) is a 13-item self-administered symptom questionnaire that estimates aerobic fitness expressed in metabolic equivalents (METs) and has been validated to cardiovascular patients. The purpose of this study was to assess the validity and reliability of the VSAQ in older adults without specific health conditions. A methodological study with a cross-sectional design was conducted with 28 older adults (66-86 years). The VSAQ was administered on 3 occasions by 2 evaluators. Aerobic capacity in METs as measured by the VSAQ was compared with the METs found in an incremental shuttle walk test (ISWT) performed with a portable metabolic measurement system and with accelerometer data. The validity of the VSAQ was found to be moderate-to-good when compared with the METs and distance measured by the ISWT and with the moderate activity per day and steps per day obtained by accelerometry. The Bland-Altman graph analysis showed no values outside the limits of agreement, suggesting good precision between the METs estimated by questionnaire and the METs measured by the ISWT. Also, the intrarater and interrater reliabilities of the instrument were good. The results showed that the VSAQ is a valuable tool to assess the aerobic fitness of older adults.

  18. Maternal diets trigger sex-specific divergent trajectories of gene expression and epigenetic systems in mouse placenta.

    Directory of Open Access Journals (Sweden)

    Anne Gabory

    Full Text Available Males and females responses to gestational overnutrition set the stage for subsequent sex-specific differences in adult onset non communicable diseases. Placenta, as a widely recognized programming agent, contibutes to the underlying processes. According to our previous findings, a high-fat diet during gestation triggers sex-specific epigenetic alterations within CpG and throughout the genome, together with the deregulation of clusters of imprinted genes. We further investigated the impact of diet and sex on placental histology, transcriptomic and epigenetic signatures in mice. Both basal gene expression and response to maternal high-fat diet were sexually dimorphic in whole placentas. Numerous genes showed sexually dimorphic expression, but only 11 genes regardless of the diet. In line with the key role of genes belonging to the sex chromosomes, 3 of these genes were Y-specific and 3 were X-specific. Amongst all the genes that were differentially expressed under a high-fat diet, only 16 genes were consistently affected in both males and females. The differences were not only quantitative but remarkably qualitative. The biological functions and networks of genes dysregulated differed markedly between the sexes. Seven genes of the epigenetic machinery were dysregulated, due to effects of diet, sex or both, including the Y- and X-linked histone demethylase paralogues Kdm5c and Kdm5d, which could mark differently male and female epigenomes. The DNA methyltransferase cofactor Dnmt3l gene expression was affected, reminiscent of our previous observation of changes in global DNA methylation. Overall, this striking sexual dimorphism of programming trajectories impose a considerable revision of the current dietary interventions protocols.

  19. Timing of Maternal Depression and Sex-Specific Child Growth, the Upstate KIDS Study.

    Science.gov (United States)

    Park, Hyojun; Sundaram, Rajeshwari; Gilman, Stephen E; Bell, Griffith; Louis, Germaine M Buck; Yeung, Edwina H

    2018-01-01

    Equivocal findings have been reported on the association between maternal depression and children's growth, possibly because of the limited attention to its disproportionate impact by child sex. The relationship between the timing of maternal depression and children's growth was assessed in a population-based prospective birth cohort, with particular attention to sex differences. The Upstate KIDS Study comprised 4,394 children followed through 3 years of age from 2008 to 2010. Maternal depression was measured antenatally by linkage with hospital discharge records before delivery and postnatally by depressive symptoms reported from questionnaires. Children's growth was measured by sex- and age-specific weight, height, weight for height, and BMI. Adjusted linear mixed effects models were used to estimate growth outcomes for the full sample and separately by plurality and sex. Antenatal depression was associated with lower weight for age (-0.24 z score units; 95% confidence interval [CI]: -0.43, -0.05) and height for age (-0.26 z score units; 95% CI: -0.51, -0.02) among singleton boys. Postnatal depressive symptoms were associated with higher weight for height (0.21 z score units; 95% CI: 0.01, 0.42) among singleton girls. The findings of this study suggest that antenatal depression was associated with lower weight and smaller height only for boys, whereas postnatal depressive symptoms were associated with higher weight for height only for girls. The timing of depression and the mechanisms of sex-specific responses require further examination. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  20. Sex-specific neural circuits of emotion regulation in the centromedial amygdala.

    Science.gov (United States)

    Wu, Yan; Li, Huandong; Zhou, Yuan; Yu, Jian; Zhang, Yuanchao; Song, Ming; Qin, Wen; Yu, Chunshui; Jiang, Tianzi

    2016-03-23

    Sex-related differences in emotion regulation (ER) in the frequency power distribution within the human amygdala, a brain region involved in emotion processing, have been reported. However, how sex differences in ER are manifested in the brain networks which are seeded on the amygdala subregions is unclear. The goal of this study was to investigate this issue from a brain network perspective. Utilizing resting-state functional connectivity (RSFC) analysis, we found that the sex-specific functional connectivity patterns associated with ER trait level were only seeded in the centromedial amygdala (CM). Women with a higher trait-level ER had a stronger negative RSFC between the right CM and the medial superior frontal gyrus (mSFG), and stronger positive RSFC between the right CM and the anterior insula (AI) and the superior temporal gyrus (STG). But men with a higher trait-level ER was associated with weaker negative RSFC of the right CM-mSFG and positive RSFCs of the right CM-left AI, right CM-right AI/STG, and right CM-left STG. These results provide evidence for the sex-related effects in ER based on CM and indicate that men and women may differ in the neural circuits associated with emotion representation and integration.

  1. Uptake of a women-only, sex-work-specific drop-in center and links with sexual and reproductive health care for sex workers.

    Science.gov (United States)

    Kim, Soyoun Rachel; Goldenberg, Shira M; Duff, Putu; Nguyen, Paul; Gibson, Kate; Shannon, Kate

    2015-03-01

    To longitudinally examine female sex workers' (FSWs') uptake of a women-only, sex-work-specific drop-in service and its impact on their access to sexual and reproductive health (SRH) services. For the present longitudinal analysis, data were drawn from the AESHA (An Evaluation of Sex Workers' Health Access) study, a community-based, open, prospective cohort of FSWs from Vancouver, BC, Canada. Data obtained between January 2010 and February 2013 were analyzed. Participants are followed up on a semi-annual basis. Multivariable logistic regression using generalized estimating equations was used to identify correlates of service uptake. Of 547 FSWs included in the present analysis, 330 (60.3%) utilized the services during the 3-year study period. Service use was independently associated with age (adjusted odds ratio [AOR] 1.04; 95% confidence interval [CI] 1.03-1.06), Aboriginal ancestry (AOR 2.18; 95% CI 1.61-2.95), injection drug use (AOR 1.67; 95% CI 1.29-2.17), exchange of sex for drugs (AOR 1.40; 95%CI 1.15-1.71), and accessing SRH services (AOR 1.65; 95% CI 1.35-2.02). A sex-work-specific drop-in space for marginalized FSWs had high uptake. Women-centered and low-threshold drop-in services can effectively link marginalized women with SRH services. Copyright © 2014 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

  2. Sex-specific differences in transcriptome profiles of brain and muscle tissue of the tropical gar.

    Science.gov (United States)

    Cribbin, Kayla M; Quackenbush, Corey R; Taylor, Kyle; Arias-Rodriguez, Lenin; Kelley, Joanna L

    2017-04-07

    The tropical gar (Atractosteus tropicus) is the southernmost species of the seven extant species of gar fishes in the world. In Mexico and Central America, the species is an important food source due to its nutritional quality and low price. Despite its regional importance and increasing concerns about overexploitation and habitat degradation, basic genetic information on the tropical gar is lacking. Determining genetic information on the tropical gar is important for the sustainable management of wild populations, implementation of best practices in aquaculture settings, evolutionary studies of ancient lineages, and an understanding of sex-specific gene expression. In this study, the transcriptome of the tropical gar was sequenced and assembled de novo using tissues from three males and three females using Illumina sequencing technology. Sex-specific and highly differentially expressed transcripts in brain and muscle tissues between adult males and females were subsequently identified. The transcriptome was assembled de novo resulting in 80,611 transcripts with a contig N50 of 3,355 base pairs and over 168 kilobases in total length. Male muscle, brain, and gonad as well as female muscle and brain were included in the assembly. The assembled transcriptome was annotated to identify the putative function of expressed transcripts using Trinotate and SwissProt, a database of well-annotated proteins. The brain and muscle datasets were then aligned to the assembled transcriptome to identify transcripts that were differentially expressed between males and females. The contrast between male and female brain identified 109 transcripts from 106 genes that were significantly differentially expressed. In the muscle comparison, 82 transcripts from 80 genes were identified with evidence for significant differential expression. Almost all genes identified as differentially expressed were sex-specific. The differentially expressed transcripts were enriched for genes involved in

  3. Identification and Validation of a New Male Sex-Specific ISSR Marker in Pointed Gourd (Trichosanthes dioica Roxb.

    Directory of Open Access Journals (Sweden)

    Sinchan Adhikari

    2014-01-01

    Full Text Available The aim of the present study was to develop a genetic sex marker for the pointed gourd (Trichosanthes dioica Roxb. to allow gender determination at any stage in the life cycle. Screening of genomic DNA with intersimple sequence repeat (ISSR primers was used to discover sex-specific touch-down polymerase chain reaction (Td-PCR amplification products. Using pooled DNA from male and female genotypes and 42 ISSR primers, a putative male specific marker (~550 bp was identified. DNA marker specific to male is an indication of existence of nonepigenetic factors involved in gender development in pointed gourd. The ISSR technique has proved to be a reliable technique in gender determination of pointed gourd genotypes at the seedling phenophase. The sex marker developed here could also be used as a starting material towards sequence characterization of sex linked genes for better understanding the developmental as well as evolutionary pathways in sexual dimorphism.

  4. Small but mighty: the evolutionary dynamics of W and Y sex chromosomes.

    Science.gov (United States)

    Mank, Judith E

    2012-01-01

    Although sex chromosomes have been the focus of a great deal of scientific scrutiny, most interest has centred on understanding the evolution and relative importance of X and Z chromosomes. By contrast, the sex-limited W and Y chromosomes have received far less attention, both because of their generally degenerate nature and the difficulty in studying non-recombining and often highly heterochromatic genomic regions. However, recent theory and empirical evidence suggest that the W and Y chromosomes play a far more important role in sex-specific fitness traits than would be expected based on their size alone, and this importance may explain the persistence of some Y and W chromosomes in the face of powerful degradative forces. In addition to their role in fertility and fecundity, the sex-limited nature of these genomic regions results in unique evolutionary forces acting on Y and W chromosomes, implicating them as potentially major contributors to sexual selection and speciation. Recent empirical studies have borne out these predictions and revealed that some W and Y chromosomes play a vital role in key sex-specific evolutionary processes.

  5. Involvement of the oxytocin system in the bed nucleus of the stria terminalis in the sex-specific regulation of social recognition

    Science.gov (United States)

    Dumais, Kelly M.; Alonso, Andrea G.; Immormino, Marisa A.; Bredewold, Remco; Veenema, Alexa H.

    2015-01-01

    Sex differences in the oxytocin (OT) system in the brain may explain why OT often regulates social behaviors in sex-specific ways. However, a link between sex differences in the OT system and sex-specific regulation of social behavior has not been tested. Here, we determined whether sex differences in the OT receptor (OTR) or in OT release in the posterior bed nucleus of the stria terminalis (pBNST) mediates sex-specific regulation of social recognition in rats. We recently showed that, compared to female rats, male rats have a three-fold higher OTR binding density in the pBNST, a sexually dimorphic area implicated in the regulation of social behaviors. We now demonstrate that OTR antagonist (5 ng/0.5 μl/side) administration into the pBNST impairs social recognition in both sexes, while OT (100 pg/0.5 μl/side) administration into the pBNST prolongs the duration of social recognition in males only. These effects seem specific to social recognition, as neither treatment altered total social investigation time in either sex. Moreover, baseline OT release in the pBNST, as measured with in vivo microdialysis, did not differ between the sexes. However, males showed higher OT release in the pBNST during social recognition compared to females. These findings suggest a sex-specific role of the OT system in the pBNST in the regulation of social recognition. PMID:26630388

  6. Involvement of the oxytocin system in the bed nucleus of the stria terminalis in the sex-specific regulation of social recognition.

    Science.gov (United States)

    Dumais, Kelly M; Alonso, Andrea G; Immormino, Marisa A; Bredewold, Remco; Veenema, Alexa H

    2016-02-01

    Sex differences in the oxytocin (OT) system in the brain may explain why OT often regulates social behaviors in sex-specific ways. However, a link between sex differences in the OT system and sex-specific regulation of social behavior has not been tested. Here, we determined whether sex differences in the OT receptor (OTR) or in OT release in the posterior bed nucleus of the stria terminalis (pBNST) mediates sex-specific regulation of social recognition in rats. We recently showed that, compared to female rats, male rats have a three-fold higher OTR binding density in the pBNST, a sexually dimorphic area implicated in the regulation of social behaviors. We now demonstrate that OTR antagonist (5 ng/0.5 μl/side) administration into the pBNST impairs social recognition in both sexes, while OT (100 pg/0.5 μl/side) administration into the pBNST prolongs the duration of social recognition in males only. These effects seem specific to social recognition, as neither treatment altered total social investigation time in either sex. Moreover, baseline OT release in the pBNST, as measured with in vivo microdialysis, did not differ between the sexes. However, males showed higher OT release in the pBNST during social recognition compared to females. These findings suggest a sex-specific role of the OT system in the pBNST in the regulation of social recognition. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Curious Sex Ratios and Cytoplasmic Genes

    Indian Academy of Sciences (India)

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

  8. Evaluation of Sex-Specific Gene Expression in Archived Dried Blood Spots (DBS

    Directory of Open Access Journals (Sweden)

    Scott Jewell

    2012-08-01

    Full Text Available Screening newborns for treatable serious conditions is mandated in all US states and many other countries. After screening, Guthrie cards with residual blood (whole spots or portions of spots are typically stored at ambient temperature in many facilities. The potential of archived dried blood spots (DBS for at-birth molecular studies in epidemiological and clinical research is substantial. However, it is also challenging as analytes from DBS may be degraded due to preparation and storage conditions. We previously reported an improved assay for obtaining global RNA gene expression from blood spots. Here, we evaluated sex-specific gene expression and its preservation in DBS using oligonucleotide microarray technology. We found X inactivation-specific transcript (XIST, lysine-specific demethylase 5D (KDM5D (also known as selected cDNA on Y, homolog of mouse (SMCY, uncharacterized LOC729444 (LOC729444, and testis-specific transcript, Y-linked 21 (TTTY21 to be differentially-expressed by sex of the newborn. Our finding that trait-specific RNA gene expression is preserved in unfrozen DBS, demonstrates the technical feasibility of performing molecular genetic profiling using such samples. With millions of DBS potentially available for research, we see new opportunities in using newborn molecular gene expression to better understand molecular pathogenesis of perinatal diseases.

  9. Transgenic over-expression of YY1 induces pathologic cardiac hypertrophy in a sex-specific manner

    Science.gov (United States)

    Stauffer, Brian L.; Dockstader, Karen; Russell, Gloria; Hijmans, Jamie; Walker, Lisa; Cecil, Mackenzie; Demos-Davies, Kimberly; Medway, Allen; McKinsey, Timothy A.; Sucharov, Carmen C.

    2015-01-01

    YY1 can activate or repress transcription of various genes. In cardiac myocytes in culture YY1 has been shown to regulate expression of several genes involved in myocyte pathology. YY1 can also acutely protect the heart against detrimental changes in gene expression. In this study we show that cardiac over-expression of YY1 induces pathologic cardiac hypertrophy in male mice, measured by changes in gene expression and lower ejection fraction/fractional shortening. In contrast, female animals are protected against pathologic gene expression changes and cardiac dysfunction. Furthermore, we show that YY1 regulates, in a sex-specific manner, the expression of mammalian enable (Mena), a factor that regulates cytoskeletal actin dynamics and whose expression is increased in several models of cardiac pathology, and that Mena expression in humans with heart failure is sex-dependent. Finally, we show that sex differences in YY1 expression are also observed in human heart failure. In summary, this is the first work to show that YY1 has a sex-specific effect in the regulation of cardiac pathology. PMID:25935483

  10. Cardiorespiratory Fitness and Blood Pressure: A Longitudinal Analysis.

    Science.gov (United States)

    Agostinis-Sobrinho, César; Ruiz, Jonatan R; Moreira, Carla; Abreu, Sandra; Lopes, Luís; Oliveira-Santos, José; Mota, Jorge; Santos, Rute

    2018-01-01

    To examine the association between cardiorespiratory fitness and cardiovascular indices 2 years later, and to determine whether changes in cardiorespiratory fitness are associated with cardiovascular indices at a 2-year follow-up in adolescents. The sample comprised 734 adolescents (349 girls) aged 12-18 years followed for 3 years from the LabMed Physical Activity Study. Cardiorespiratory fitness was assessed by the 20-meter shuttle run test. Height, weight, waist circumference, and resting blood pressure (BP) were measured according to standard procedures. Regression analyses showed a significant inverse association between cardiorespiratory fitness at baseline and systolic BP (B = -0.126; P = .047) and rate pressure product (B = -29.94; P = .016), at follow-up after adjustments for age, sex, height, pubertal stage, socioeconomic status, and waist circumference. Significant differences were found between cardiorespiratory fitness groups (fit vs unfit) at baseline and systolic BP and rate pressure product at follow-up (P fitness changes and systolic BP (P = .024) and rate pressure product (P = .014), after adjustment for age, sex, height, pubertal status, socioeconomic status, and waist circumference. Changes in cardiorespiratory fitness during adolescence were associated with cardiovascular indices over a 2-year period. Adolescents with persistently low levels of cardiorespiratory fitness exhibited the highest levels of systolic BP and rate pressure product. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Sex differences in the vaccine-specific and non-targeted effects of vaccines

    DEFF Research Database (Denmark)

    Flanagan, Katie L; Klein, Sabra L; Skakkebaek, Niels E

    2011-01-01

    to eliminate infectious diseases through vaccination programmes, the relative impact of NSE of vaccines on mortality is likely to increase, raising important questions regarding the future of certain vaccine schedules. A diverse group of scientists met in Copenhagen to discuss non-specific and sex...

  12. Postzygotic isolation involves strong mitochondrial and sex-specific effects in Tigriopus californicus, a species lacking heteromorphic sex chromosomes.

    Science.gov (United States)

    Foley, B R; Rose, C G; Rundle, D E; Leong, W; Edmands, S

    2013-11-01

    Detailed studies of the genetics of speciation have focused on a few model systems, particularly Drosophila. The copepod Tigriopus californicus offers an alternative that differs from standard animal models in that it lacks heteromorphic chromosomes (instead, sex determination is polygenic) and has reduced opportunities for sexual conflict, because females mate only once. Quantitative trait loci (QTL) mapping was conducted on reciprocal F2 hybrids between two strongly differentiated populations, using a saturated linkage map spanning all 12 autosomes and the mitochondrion. By comparing sexes, a possible sex ratio distorter was found but no sex chromosomes. Although studies of standard models often find an excess of hybrid male sterility factors, we found no QTL for sterility and multiple QTL for hybrid viability (indicated by non-Mendelian adult ratios) and other characters. Viability problems were found to be stronger in males, but the usual explanations for weaker hybrid males (sex chromosomes, sensitivity of spermatogenesis, sexual selection) cannot fully account for these male viability problems. Instead, higher metabolic rates may amplify deleterious effects in males. Although many studies of standard speciation models find the strongest genetic incompatibilities to be nuclear-nuclear (specifically X chromosome-autosome), we found the strongest deleterious interaction in this system was mito-nuclear. Consistent with the snowball theory of incompatibility accumulation, we found that trigenic interactions in this highly divergent cross were substantially more frequent (>6×) than digenic interactions. This alternative system thus allows important comparisons to studies of the genetics of reproductive isolation in more standard model systems.

  13. Global, regional, and national age–sex specific all-cause and cause-specific mortality for 240 causes of death, 1990–2013

    NARCIS (Netherlands)

    Geleijnse, J.M.

    2015-01-01

    Background

    Up-to-date evidence on levels and trends for age-sex-specific all-cause and cause-specific mortality is essential for the formation of global, regional, and national health policies. In the Global Burden of Disease Study 2013 (GBD 2013) we estimated yearly deaths for 188

  14. High Satisfaction and Return to Sports After Total Shoulder Arthroplasty in Patients Aged 55 Years and Younger.

    Science.gov (United States)

    Garcia, Grant H; Liu, Joseph N; Sinatro, Alec; Wu, Hao-Hua; Dines, Joshua S; Warren, Russell F; Dines, David M; Gulotta, Lawrence V

    2017-06-01

    Young, active candidates for total shoulder arthroplasty (TSA) are a unique group of patients. Not only do they demand longevity and improved function, but they also desire a return to physical activities. To determine the rate of return to sports in patients aged ≤55 years undergoing TSA. Case series; Level of evidence, 4. This was a retrospective review of consecutive patients who underwent anatomic TSA at a single institution. Exclusion criteria included age at the time of surgery >55 years and sports questionnaire, American Shoulder and Elbow Surgeons (ASES) score, and visual analog scale (VAS) score. From 70 eligible patients, 59 patients (61 shoulders) were included with an average follow-up of 61.0 months (range, 25-103 months) and average age at the time of surgery of 48.9 years (range, 25-55 years). The average VAS score improved from 5.6 to 0.9 ( P sports. Moreover, patients in 96.4% of shoulders (55/57) restarted at least 1 sport at an average of 6.7 months. Direct rates of return were as follows: fitness sports (97.2%), golf (93.3%), singles tennis (87.5%), swimming (77.7%), basketball (75.0%), and flag football (66.7%). Patients in 47 shoulders (82.4%) returned to a similar or higher level of sports; 90.3% returned to high-demand sports, and 83.8% returned to high upper extremity sports. There was no significant difference in rates of return to sports by body mass index, sex, age, preoperative diagnosis, revision status, and dominant extremity. In patients aged ≤55 years undergoing TSA, there was a 96.4% rate of return to ≥1 previous sports at an average of 6.7 months. Furthermore, at an average follow-up of 61.0 months, no patients needed revision of their glenoid component, despite an 83.8% rate of return to high upper extremity sports. While caution should still be advised in young, active patients undergoing TSA, these results demonstrate a high satisfaction rate and improved ability to return to most sports after surgery.

  15. Strong inverse association between physical fitness and overweight in adolescents: a large school-based survey

    Directory of Open Access Journals (Sweden)

    Auguste Robert

    2007-06-01

    Full Text Available Abstract Background Studies examining the relationship between physical fitness and obesity in children have had mixed results despite their interrelationship making intuitive sense. We examined the relationship between physical fitness and overweight and obesity in a large sample of adolescents in the Republic of Seychelles (Indian Ocean, African region. Methods All students of four grades of all secondary schools performed nine physical fitness tests. These tests assessed agility, strength and endurance, and included the multistage shuttle run, a validated measure of maximal oxygen uptake. Weight and height were measured, body mass index (BMI calculated, and "overweight" and "obesity" were defined based on the criteria of the International Obesity Task Force. We defined "lean" weight as age- and sex-specific BMI th percentile. Age- and sex-specific percentiles for each fitness test were calculated. "Good" performance was defined as a result ≥75th percentile. Results Data were available in 2203 boys and 2143 girls from a total of 4599 eligible students aged 12–15 years. The prevalence of overweight (including obesity was 11.2% (95% confidence interval: 9.9–12.4 in boys and 17.5% (15.9–19.1 in girls. For 7 of the 9 tests, the relationship between BMI and fitness score, as assessed by locally weighted regression, was characterized by a marked inverse J shape. Students with normal body weight achieved "good" performance markedly more often than overweight or obese students on 7 of the 9 tests of fitness and more often than lean children. For example, good performance for the multistage shuttle run was achieved by 25.6% (SE: 2.1 of lean students, 29.6% (0.8 of normal weight students, 7.9% (1.3 of overweight students and 1.2% (0.9 of obese students. Conclusion This cross-sectional study shows a strong inverse relationship between fitness and excess body weight in adolescents. Improving fitness in adolescents, likely through increasing

  16. Gaming for Safer Sex: Young German and Turkish People Report No Specific Culture-Related Preferences Toward Educational Games Promoting Safer Sex.

    Science.gov (United States)

    Brüll, Phil; Ruiter, Robert A C; Wiers, Reinout W; Kok, Gerjo

    2016-12-01

    Comprehensive sex education programs specifically designed for adolescents and young adults that take into account gender norms and cultural background have shown promise as a means of countering the high sexually transmitted infection rate in young people. Recently, digital gaming interventions delivered on computers or mobile devices have emerged as another way to promote safer sex behavior in a young population. Tailoring these computer-based interventions to their target population has been recognized to increase positive behavior outcomes. In this qualitative study, we investigated whether young female and male adults from two different cultural backgrounds (all living in Germany) would have different preferences and needs in relation to an educational game promoting safer sex. We conducted four semistructured focus group interviews comprising open-ended questions with male and female participants who had either a German or a Turkish background. In total, 20 individuals, aged between 18 and 22 years, from two socially diverse and ethnically mixed vocational schools in Germany participated. Independent of cultural background and gender, participants preferred a real-world design with a first-person visual perspective over a fantasy-like third-person perspective. Furthermore, they preferred highly customizable avatars. All participants mentioned the importance of including an alcohol-intoxicated avatar and most participants wanted there to be additional information available about various safer sex approaches and about the use of different barrier protection methods. Males and females reported similar preferences for the design of an educational game promoting safer sex, with the only difference being exactly how the topic of having sexual intercourse should be addressed in the game. Males preferred a direct approach, whereas females had a preference for treating this subject more sympathetically. Educational games offer anonymity and can provide young people

  17. Sex-specific metabolic profiles of androgens and its main binding protein SHBG in a middle aged population without diabetes

    DEFF Research Database (Denmark)

    Piontek, Uwe; Wallaschofski, Henri; Kastenmüller, Gabi

    2017-01-01

    The role of androgens in metabolism with respect to sex-specific disease associations is poorly understood. Therefore, we aimed to provide molecular signatures in plasma and urine of androgen action in a sex-specific manner using state-of-the-art metabolomics techniques. Our study population...

  18. Sex-Specific Response Strategies in Mental Rotation

    Science.gov (United States)

    Hirnstein, Marco; Bayer, Ulrike; Hausmann, Markus

    2009-01-01

    The present study investigated whether the marked sex difference in the original mental rotation test (MRT) is simply a result of sex differences in response strategies. Thirty-four participants (17 males, 17 females) completed the revised Vandenberg and Kuse MRT [Peters, M., Laeng, B., Latham, K., Jackson, M., Zaiyouna, R., & Richardson, C.…

  19. Predictors of the sex offender civil commitment trial outcomes in New York State.

    Science.gov (United States)

    Lu, Yunmei; Freeman, Naomi J; Sandler, Jeffrey C

    2015-10-01

    The present study analyzed sex offender civil management (i.e., civil commitment) legal proceedings in New York State and identified factors that predict trial results. Specifically, the current study compared a sample of 38 sex offenders who were released to the community after winning their civil management trials to 183 sex offenders who lost their civil management trials. Additionally, for the 183 sex offenders who lost their civil management trials, the current study compared 146 offenders who were ordered to inpatient civil commitment to 37 offenders who were deemed fit for civil management in the community. Results of the analyses indicated that sexual criminality, sexual deviance, and criminality involving child victims increased the likelihood of offenders both losing their civil management trial and being found to be in need of inpatient care, while the presence of variables associated with nonsexual criminality increased the likelihood of offenders both winning their civil management trials and being deemed fit for management in the community. The findings of this study provide guidance for psychiatric examiners who testify in civil management legal proceedings, as well as for legal professionals specializing in civil management cases. (c) 2015 APA, all rights reserved).

  20. On Modelling Long Term Stock Returns with Ergodic Diffusion Processes: Arbitrage and Arbitrage-Free Specifications

    Directory of Open Access Journals (Sweden)

    Bernard Wong

    2009-01-01

    martingale component is based on an ergodic diffusion with a specified stationary distribution. These models are particularly useful for long horizon asset-liability management as they allow the modelling of long term stock returns with heavy tail ergodic diffusions, with tractable, time homogeneous dynamics, and which moreover admit a complete financial market, leading to unique pricing and hedging strategies. Unfortunately the standard specifications of these models in literature admit arbitrage opportunities. We investigate in detail the features of the existing model specifications which create these arbitrage opportunities and consequently construct a modification that is arbitrage free.

  1. Computing return times or return periods with rare event algorithms

    Science.gov (United States)

    Lestang, Thibault; Ragone, Francesco; Bréhier, Charles-Edouard; Herbert, Corentin; Bouchet, Freddy

    2018-04-01

    The average time between two occurrences of the same event, referred to as its return time (or return period), is a useful statistical concept for practical applications. For instance insurances or public agencies may be interested by the return time of a 10 m flood of the Seine river in Paris. However, due to their scarcity, reliably estimating return times for rare events is very difficult using either observational data or direct numerical simulations. For rare events, an estimator for return times can be built from the extrema of the observable on trajectory blocks. Here, we show that this estimator can be improved to remain accurate for return times of the order of the block size. More importantly, we show that this approach can be generalised to estimate return times from numerical algorithms specifically designed to sample rare events. So far those algorithms often compute probabilities, rather than return times. The approach we propose provides a computationally extremely efficient way to estimate numerically the return times of rare events for a dynamical system, gaining several orders of magnitude of computational costs. We illustrate the method on two kinds of observables, instantaneous and time-averaged, using two different rare event algorithms, for a simple stochastic process, the Ornstein–Uhlenbeck process. As an example of realistic applications to complex systems, we finally discuss extreme values of the drag on an object in a turbulent flow.

  2. Sexual Orientation, Drug Use Preference during Sex, and HIV Risk Practices and Preferences among Men Who Specifically Seek Unprotected Sex Partners via the Internet

    Directory of Open Access Journals (Sweden)

    Hugh Klein

    2009-05-01

    Full Text Available The present study entailed conducting a content analysis of 1,434 ads/profiles posted on one of the most popular “Men who have Sex with Men” (MSM websites that specifically fosters unprotected sex. Ads/profiles were selected randomly based on the American ZIP code of residence (n = 1,316, with a randomly-drawn oversampling of profiles of men who self-identified as heterosexual or ���curious” rather than gay or bisexual (n = 118. Data were collected between September 2006 and September 2007. The purpose of the present paper is to examine the conjoint effects of self-identified sexual orientation and preference for having/not having sex while high, on men’s sought-after sexual risk. Analytical comparisons of the four groups showed that, on most measures, the combination of sexual orientation and drug use preference during sex differentiated the men. Generally speaking, gay/bisexual men who advertised online for partners with whom they could have sex while high expressed the greatest interest in risky sexual behaviors (e.g., felching, unprotected oral sex, unprotected anal sex and various risk-related preferences (e.g., multiple partner sex, anonymous sex, eroticizing ejaculatory fluids. This is especially true when they are compared to their heterosexual/“curious” counterparts whose online profiles were not as likely to indicate a desire for having sex while high.

  3. Sex-specific neuroanatomical correlates of fear expression in prefrontal-amygdala circuits.

    Science.gov (United States)

    Gruene, Tina M; Roberts, Elian; Thomas, Virginia; Ronzio, Ashley; Shansky, Rebecca M

    2015-08-01

    The neural projections from the infralimbic region of the prefrontal cortex to the amygdala are important for the maintenance of conditioned fear extinction. Neurons in this pathway exhibit a unique pattern of structural plasticity that is sex-dependent, but the relationship between the morphologic characteristics of these neurons and successful extinction in male and female subjects is unknown. Using classic cued fear conditioning and an extinction paradigm in large cohorts of male and female rats, we identified subpopulations of both sexes that exhibited high (HF) or low (LF) levels of freezing on an extinction retrieval test, representing failed or successful extinction maintenance, respectively. We combined retrograde tracing with fluorescent intracellular microinjections to perform three-dimensional reconstructions of infralimbic neurons that project to the basolateral amygdala in these groups. The HF and LF male rats exhibited neuroanatomical distinctions that were not observed in HF or LF female rats. A retrospective analysis of behavior during fear conditioning and extinction revealed that despite no overall sex differences in freezing behavior, HF and LF phenotypes emerged in male rats during extinction and in female rats during fear conditioning, which does not involve infralimbic-basolateral amygdala neurons. Our results suggest that the neural processes underlying successful or failed extinction maintenance may be sex-specific. These findings are relevant not only to future basic research on sex differences in fear conditioning and extinction but also to exposure-based clinical therapies, which are similar in premise to fear extinction and which are primarily used to treat disorders that are more common in women than in men. Copyright © 2015 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  4. Sex- and Site-Specific Normative Data Curves for HR-pQCT.

    Science.gov (United States)

    Burt, Lauren A; Liang, Zhiying; Sajobi, Tolulope T; Hanley, David A; Boyd, Steven K

    2016-11-01

    The purpose of this study was to develop age-, site-, and sex-specific centile curves for common high-resolution peripheral quantitative computed tomography (HR-pQCT) and finite-element (FE) parameters for males and females older than 16 years. Participants (n = 866) from the Calgary cohort of the Canadian Multicentre Osteoporosis Study (CaMos) between the ages of 16 and 98 years were included in this study. Participants' nondominant radius and left tibia were scanned using HR-pQCT. Standard and automated segmentation methods were performed and FE analysis estimated apparent bone strength. Centile curves were generated for males and females at the tibia and radius using the generalized additive models for location, scale, and shape (GAMLSS) package in R. After GAMLSS analysis, age-, sex-, and site-specific centiles (10th, 25th, 50th, 75th, 90th) for total bone mineral density and trabecular number as well as failure load have been calculated. Clinicians and researchers can use these reference curves as a tool to assess bone health and changes in bone quality. © 2016 American Society for Bone and Mineral Research. © 2016 American Society for Bone and Mineral Research.

  5. Sex-specific differences in injury types among basketball players.

    Science.gov (United States)

    Ito, Eri; Iwamoto, Jun; Azuma, Koichiro; Matsumoto, Hideo

    2015-01-01

    The purpose of the present study was to investigate sex-specific differences in injury types among basketball players. According to our database, during the 20-year period between October 1991 and June 2011, 1,219 basketball players (640 males and 579 females) consulted our sports medicine clinic; in total, 1,414 injuries in basketball players (729 injuries in males and 685 injuries in females) were recorded. The mean age of patients was 19.6 years. The most common injury site was the knee, followed by the foot and ankle, lower back, and upper extremities. There was a higher proportion of female players presenting with a knee injury, compared with male players (50.4% vs 41.7%), and a lower proportion of female players presenting with an upper extremity injury (5.1% vs 9.7%). The proportion of anterior cruciate ligament injury in the 10-19-year-old age group was higher among female players than among male players (45.9% vs 22.1%), while the proportions of Osgood-Schlatter disease in the 10-19-year-old age group and jumper's knee (patellar and femoral tendinopathy) in the 20-29-year-old age group were higher among male players than among female players (12.5% vs 1.8% and 14.6% vs 3.7%, respectively). However, the proportions of other injuries did not differ significantly between male and female players. The present observational study, which was performed using a retrospective case-series design, showed the existence of sex-specific differences in knee injuries sustained while participating in basketball.

  6. Regime switches in the risk-return trade-off

    OpenAIRE

    Marcellino, Massimiliano; Ghysels, Eric; Guerin, Pierre

    2014-01-01

    This paper deals with the estimation of the risk-return trade-off. We use a MIDAS model for the conditional variance and allow for possible switches in the risk-return relation through a Markov-switching specification. We find strong evidence for regime changes in the risk-return relation. This finding is robust to a large range of specifications. In the first regime characterized by low ex-post returns and high volatility, the risk-return relation is reversed, whereas the intuitive positive ...

  7. Long-Term Impact of Intrauterine Neuroinflammation and Treatment with Magnesium Sulphate and Betamethasone: Sex-Specific Differences in a Preterm Labor Murine Model

    Science.gov (United States)

    2017-12-20

    intrauterine neuroinflammation and treatment with magnesium sulphate and betamethasone: Sex -specific differences in a preterm labor murine model...widespread use of Mg504 in clinical practice, its effects on adult offspring are not well known nor have sex -specific differences in therapeutic...injury. Prenatal treatment with MgSOJbetamethasone confers long-term benefits beyond cerebral palsy prevention with sex -specific differences in

  8. Gaming for Safer Sex : Young German and Turkish People Report No Specific Culture-Related Preferences Toward Educational Games Promoting Safer Sex

    NARCIS (Netherlands)

    Brüll, P.; Ruiter, R.A.C.; Wiers, R.W.; Kok, G.

    2016-01-01

    OBJECTIVE: Comprehensive sex education programs specifically designed for adolescents and young adults that take into account gender norms and cultural background have shown promise as a means of countering the high sexually transmitted infection rate in young people. Recently, digital gaming

  9. Chronic stress induces sex-specific alterations in methylation and expression of corticotropin-releasing factor gene in the rat.

    Directory of Open Access Journals (Sweden)

    Linda Sterrenburg

    Full Text Available BACKGROUND: Although the higher prevalence of depression in women than in men is well known, the neuronal basis of this sex difference is largely elusive. METHODS: Male and female rats were exposed to chronic variable mild stress (CVMS after which immediate early gene products, corticotropin-releasing factor (CRF mRNA and peptide, various epigenetic-associated enzymes and DNA methylation of the Crf gene were determined in the hypothalamic paraventricular nucleus (PVN, oval (BSTov and fusiform (BSTfu parts of the bed nucleus of the stria terminalis, and central amygdala (CeA. RESULTS: CVMS induced site-specific changes in Crf gene methylation in all brain centers studied in female rats and in the male BST and CeA, whereas the histone acetyltransferase, CREB-binding protein was increased in the female BST and the histone-deacetylase-5 decreased in the male CeA. These changes were accompanied by an increased amount of c-Fos in the PVN, BSTfu and CeA in males, and of FosB in the PVN of both sexes and in the male BSTov and BSTfu. In the PVN, CVMS increased CRF mRNA in males and CRF peptide decreased in females. CONCLUSIONS: The data confirm our hypothesis that chronic stress affects gene expression and CRF transcriptional, translational and secretory activities in the PVN, BSTov, BSTfu and CeA, in a brain center-specific and sex-specific manner. Brain region-specific and sex-specific changes in epigenetic activity and neuronal activation may play, too, an important role in the sex specificity of the stress response and the susceptibility to depression.

  10. Sex-specific associations between peripheral oxytocin and emotion perception in schizophrenia.

    Science.gov (United States)

    Rubin, Leah H; Carter, C Sue; Drogos, Lauren; Jamadar, Rhoda; Pournajafi-Nazarloo, Hossein; Sweeney, John A; Maki, Pauline M

    2011-08-01

    We previously reported that higher levels of peripheral oxytocin are associated with lower levels of positive, general, and overall symptoms in women but not in men with schizophrenia. Here we investigate the influence of sex, sex steroid hormone fluctuations, and peripheral oxytocin levels on emotional processing in men and women with schizophrenia. Twenty-two women with schizophrenia and 31 female controls completed the Penn Emotion Acuity Test (PEAT), a facial emotion recognition and perception task, during two menstrual cycle phases: 1) early follicular (Days 2-4; low estrogen/progesterone) and 2) midluteal (Days 20-22; high estrogen/progesterone). Twenty-six males with schizophrenia and 26 male controls completed testing at comparable intervals. We obtained plasma hormone assays of estrogen, progesterone, testosterone, and oxytocin. No sex differences were noted on the PEAT. Plasma oxytocin levels did not fluctuate across phases of the menstrual cycle. However, female patients and controls more accurately identified facial emotions during the early follicular versus midluteal phase (pmen. Like healthy women, women with schizophrenia demonstrate menstrual-cycle dependent fluctuations in recognizing emotional cues. Like healthy women, female patients with higher levels of oxytocin perceived faces as happier. Future studies need to address whether this sex-specific relationship is associated with trust and other positive emotions, and whether exogenous oxytocin might enhance mood states and social interaction in female or all schizophrenia patients. Copyright © 2011 Elsevier B.V. All rights reserved.

  11. Small but mighty: the evolutionary dynamics of W and Y sex chromosomes

    Science.gov (United States)

    2012-01-01

    Although sex chromosomes have been the focus of a great deal of scientific scrutiny, most interest has centred on understanding the evolution and relative importance of X and Z chromosomes. By contrast, the sex-limited W and Y chromosomes have received far less attention, both because of their generally degenerate nature and the difficulty in studying non-recombining and often highly heterochromatic genomic regions. However, recent theory and empirical evidence suggest that the W and Y chromosomes play a far more important role in sex-specific fitness traits than would be expected based on their size alone, and this importance may explain the persistence of some Y and W chromosomes in the face of powerful degradative forces. In addition to their role in fertility and fecundity, the sex-limited nature of these genomic regions results in unique evolutionary forces acting on Y and W chromosomes, implicating them as potentially major contributors to sexual selection and speciation. Recent empirical studies have borne out these predictions and revealed that some W and Y chromosomes play a vital role in key sex-specific evolutionary processes. PMID:22038285

  12. Sex-specific effects of a parasite evolving in a female-biased host population.

    Science.gov (United States)

    Duneau, David; Luijckx, Pepijn; Ruder, Ludwig F; Ebert, Dieter

    2012-12-18

    Males and females differ in many ways and might present different opportunities and challenges to their parasites. In the same way that parasites adapt to the most common host type, they may adapt to the characteristics of the host sex they encounter most often. To explore this hypothesis, we characterized host sex-specific effects of the parasite Pasteuria ramosa, a bacterium evolving in naturally, strongly, female-biased populations of its host Daphnia magna. We show that the parasite proliferates more successfully in female hosts than in male hosts, even though males and females are genetically identical. In addition, when exposure occurred when hosts expressed a sexual dimorphism, females were more infected. In both host sexes, the parasite causes a similar reduction in longevity and leads to some level of castration. However, only in females does parasite-induced castration result in the gigantism that increases the carrying capacity for the proliferating parasite. We show that mature male and female Daphnia represent different environments and reveal one parasite-induced symptom (host castration), which leads to increased carrying capacity for parasite proliferation in female but not male hosts. We propose that parasite induced host castration is a property of parasites that evolved as an adaptation to specifically exploit female hosts.

  13. Sex-specific effects of a parasite evolving in a female-biased host population

    Directory of Open Access Journals (Sweden)

    Duneau David

    2012-12-01

    Full Text Available Abstract Background Males and females differ in many ways and might present different opportunities and challenges to their parasites. In the same way that parasites adapt to the most common host type, they may adapt to the characteristics of the host sex they encounter most often. To explore this hypothesis, we characterized host sex-specific effects of the parasite Pasteuria ramosa, a bacterium evolving in naturally, strongly, female-biased populations of its host Daphnia magna. Results We show that the parasite proliferates more successfully in female hosts than in male hosts, even though males and females are genetically identical. In addition, when exposure occurred when hosts expressed a sexual dimorphism, females were more infected. In both host sexes, the parasite causes a similar reduction in longevity and leads to some level of castration. However, only in females does parasite-induced castration result in the gigantism that increases the carrying capacity for the proliferating parasite. Conclusions We show that mature male and female Daphnia represent different environments and reveal one parasite-induced symptom (host castration, which leads to increased carrying capacity for parasite proliferation in female but not male hosts. We propose that parasite induced host castration is a property of parasites that evolved as an adaptation to specifically exploit female hosts.

  14. Sex-specific effects of a parasite evolving in a female-biased host population

    Science.gov (United States)

    2012-01-01

    Background Males and females differ in many ways and might present different opportunities and challenges to their parasites. In the same way that parasites adapt to the most common host type, they may adapt to the characteristics of the host sex they encounter most often. To explore this hypothesis, we characterized host sex-specific effects of the parasite Pasteuria ramosa, a bacterium evolving in naturally, strongly, female-biased populations of its host Daphnia magna. Results We show that the parasite proliferates more successfully in female hosts than in male hosts, even though males and females are genetically identical. In addition, when exposure occurred when hosts expressed a sexual dimorphism, females were more infected. In both host sexes, the parasite causes a similar reduction in longevity and leads to some level of castration. However, only in females does parasite-induced castration result in the gigantism that increases the carrying capacity for the proliferating parasite. Conclusions We show that mature male and female Daphnia represent different environments and reveal one parasite-induced symptom (host castration), which leads to increased carrying capacity for parasite proliferation in female but not male hosts. We propose that parasite induced host castration is a property of parasites that evolved as an adaptation to specifically exploit female hosts. PMID:23249484

  15. Skeletal muscle gene expression in response to resistance exercise: sex specific regulation

    Directory of Open Access Journals (Sweden)

    Burant Charles F

    2010-11-01

    Full Text Available Abstract Background The molecular mechanisms underlying the sex differences in human muscle morphology and function remain to be elucidated. The sex differences in the skeletal muscle transcriptome in both the resting state and following anabolic stimuli, such as resistance exercise (RE, might provide insight to the contributors of sexual dimorphism of muscle phenotypes. We used microarrays to profile the transcriptome of the biceps brachii of young men and women who underwent an acute unilateral RE session following 12 weeks of progressive training. Bilateral muscle biopsies were obtained either at an early (4 h post-exercise or late recovery (24 h post-exercise time point. Muscle transcription profiles were compared in the resting state between men (n = 6 and women (n = 8, and in response to acute RE in trained exercised vs. untrained non-exercised control muscle for each sex and time point separately (4 h post-exercise, n = 3 males, n = 4 females; 24 h post-exercise, n = 3 males, n = 4 females. A logistic regression-based method (LRpath, following Bayesian moderated t-statistic (IMBT, was used to test gene functional groups and biological pathways enriched with differentially expressed genes. Results This investigation identified extensive sex differences present in the muscle transcriptome at baseline and following acute RE. In the resting state, female muscle had a greater transcript abundance of genes involved in fatty acid oxidation and gene transcription/translation processes. After strenuous RE at the same relative intensity, the time course of the transcriptional modulation was sex-dependent. Males experienced prolonged changes while females exhibited a rapid restoration. Most of the biological processes involved in the RE-induced transcriptional regulation were observed in both males and females, but sex specificity was suggested for several signaling pathways including activation of notch signaling and TGF-beta signaling in females

  16. First genetic quantification of sex- and stage-specific feeding in the ubiquitous copepod Acartia tonsa

    DEFF Research Database (Denmark)

    Ismar, Stefanie M.H.; Kottmann, Johanna Sarah; Sommer, Ulrich

    2018-01-01

    -specific feeding differences between Acartia life stages and sexes, which can have implications on food-web dynamics and specific nutrient transfer to higher trophic levels in copepod populations of varying age composition under changing environmental parameters, such as rising temperatures and increasing ocean...... acidification....

  17. Mates but not sexes differ in migratory niche in a monogamous penguin species.

    Science.gov (United States)

    Thiebot, Jean-Baptiste; Bost, Charles-André; Dehnhard, Nina; Demongin, Laurent; Eens, Marcel; Lepoint, Gilles; Cherel, Yves; Poisbleau, Maud

    2015-09-01

    Strong pair bonds generally increase fitness in monogamous organisms, but may also underlie the risk of hampering it when re-pairing fails after the winter season. We investigated whether partners would either maintain contact or offset this risk by exploiting sex-specific favourable niches during winter in a migratory monogamous seabird, the southern rockhopper penguin Eudyptes chrysocome. Using light-based geolocation, we show that although the spatial distribution of both sexes largely overlapped, pair-wise mates were located on average 595 ± 260 km (and up to 2500 km) apart during winter. Stable isotope data also indicated a marked overlap between sex-specific isotopic niches (δ¹³C and δ¹⁵N values) but a segregation of the feeding habitats (δ¹³C values) within pairs. Importantly, the tracked females remained longer (12 days) at sea than males, but all re-mated with their previous partners after winter. Our study provides multiple evidence that migratory species may well demonstrate pair-wise segregation even in the absence of sex-specific winter niches (spatial and isotopic). We suggest that dispersive migration patterns with sex-biased timings may be a sufficient proximal cause for generating such a situation in migratory animals.

  18. Prenatal stress challenge impairs fetal lung development and asthma severity sex-specifically in mice.

    Science.gov (United States)

    Zazara, Dimitra E; Perani, Clara V; Solano, María E; Arck, Petra C

    2018-02-01

    Allergic asthma is an increasing health problem worldwide. Interestingly, prenatal challenges such as stress have been associated with an increased risk for asthma during childhood. The underlying pathogenesis of how prenatal stress increases the risk for asthma still remains unclear. Potential targets could be that the fetal immune ontogeny or fetal lung development are compromised by prenatal challenges. Here, we aimed to identify whether prenatal stress challenge affects fetal lung development in mice. C57BL/6 pregnant mice were challenged with sound stress and fetal lung development was assessed histologically. Whilst prenatal stress challenge did not profoundly affect lung development in male fetuses, it resulted in less extensive terminal sacs, surrounded by thicker mesenchymal tissue in female fetuses. Thus, prenatal stress disrupted fetal lung development sex-specifically. Interestingly, upon prenatal stress challenge, the airway hyperresponsiveness and eosinophilic inflammation- two hallmarks of asthma - were significantly increased in adult female offspring, whilst regulatory CD4+ T cells were reduced. These findings strongly underpin the sex-specific association between s challenged fetal development and a sex-specific altered severity of asthma in adult offspring. Our model now allows to identify maternal markers through which the risk for asthma and possible other diseases is vertically transferred before birth in response to challenges. Such identification then opens avenues for primary disease prevention. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Analysis of sex-specific injury patterns and risk factors in young high-level athletes.

    Science.gov (United States)

    Frisch, A; Seil, R; Urhausen, A; Croisier, J L; Lair, M L; Theisen, D

    2009-12-01

    This study analyzed sex-specific injury patterns and risk factors in young athletes (n=256) from 12 sport disciplines practicing at the national or the international level in the Grand-Duchy of Luxembourg. Injury occurrence as a result of sport practice was analyzed retrospectively over the year 2006 using a standardized self-administered questionnaire. Overall incidence was not different between girls and boys (1.20 and 1.21 injuries/1000 athlete-hours, respectively), but in the context of team sport competition girls tended to be at a greater risk (rate ratio 2.05, P=0.053). Girls had a higher proportion of injuries in the ankle/foot region compared with boys (34.8% vs 16.8%). No sex-related differences were found regarding injury severity. Multivariate logistic regression (controlling for age and practice volume) revealed that girls' team sports were associated with a greater injury risk compared with individual sports [odds ratio (OR) of 4.76], while in boys this was observed for racket sports (OR=3.31). Furthermore, physical or emotional stress tended to be a specific risk factor in girls. There was a tendency for injury outside sports to be coupled to a higher injury risk in girls and boys. Consideration of sex-specific injury patterns and risk factors could be of importance for effective injury prevention.

  20. Social status affects the degree of sex difference in the songbird brain.

    Directory of Open Access Journals (Sweden)

    Cornelia Voigt

    Full Text Available It is thought that neural sex differences are functionally related to sex differences in the behaviour of vertebrates. A prominent example is the song control system of songbirds. Inter-specific comparisons have led to the hypothesis that sex differences in song nuclei size correlate with sex differences in song behaviour. However, only few species with similar song behaviour in both sexes have been investigated and not all data fit the hypothesis. We investigated the proposed structure-function relationship in a cooperatively breeding and duetting songbird, the white-browed sparrow weaver (Plocepasser mahali. This species lives in groups of 2-10 individuals, with a dominant breeding pair and male and female subordinates. While all male and female group members sing duet and chorus song, a male, once it has reached the dominant position in the group, sings an additional type of song that comprises a distinct and large syllable repertoire. Here we show for both types of male-female comparisons a male-biased sex difference in neuroanatomy of areas of the song production pathway (HVC and RA that does not correlate with the observed polymorphism in song behaviour. In contrast, in situ hybridisation of mRNA of selected genes expressed in the song nucleus HVC reveals a gene expression pattern that is either similar between sexes in female-subordinate male comparisons or female-biased in female-dominant male comparisons. Thus, the polymorphic gene expression pattern would fit the sex- and status-related song behaviour. However, this implies that once a male has become dominant it produces the duetting song with a different neural phenotype than subordinate males.

  1. Non-coding changes cause sex-specific wing size differences between closely related species of Nasonia

    NARCIS (Netherlands)

    Loehlin, David W.; Oliveira, Deodoro C. S. G.; Edwards, Rachel; Giebel, Jonathan D.; Clark, Michael E.; Cattani, M. Victoria; van de Zande, Louis; Verhulst, Eveline C.; Beukeboom, Leo W.; Munoz-Torres, Monica; Werren, John H.

    The genetic basis of morphological differences among species is still poorly understood. We investigated the genetic basis of sex-specific differences in wing size between two closely related species of Nasonia by positional cloning a major male-specific locus, wing-size1 (ws1). Male wing size

  2. Sex-specific substance abuse treatment for female healthcare professionals: implications.

    Science.gov (United States)

    Koos, Erin; Brand, Michael; Rojas, Julio; Li, Ji

    2014-01-01

    Gender plays a significant role in the development and treatment of substance abuse disorders. Sex-specific treatment for girls and women has recurrently proven more effective, with better outcomes than traditional treatment. Research on impaired healthcare professionals (HCPs) has largely focused on men, garnering little attention for women and sex differences. With the increasing numbers of female HCPs, it is imperative to identify potential sex differences that may have implications for treatment. Our study compared a convenience sample of male and female HCPs with substance abuse disorders treated in an outpatient program to identify sex differences that may have implications for treatment. Our sample consisted of 96 HCPs (54 men, 42 women) and 17 non-healthcare professional (N-HCP) women. All of the participants were evaluated using the program's clinical interview and the Personality Assessment Inventory (PAI). Chart review data contained categorical variables, qualitative variables, diagnoses, and psychological test scores. A second analysis was conducted through two separate comparisons: the PAI results of comparing impaired female HCPs with impaired male HCPs and the PAI results of comparing impaired female HCPs with impaired female N-HCPs. Statistically significant differences indicated more male participants received prior treatment and more intensive treatment than female participants. More female subjects reported being diagnosed as having a comorbid psychiatric condition and taking psychotropic medications. Several statistically significant differences in the PAI scores were found. Among female HCPs, elevations were found in anxiety, depression, paranoia, and borderline personality disorder. Substantive differences, although not statistically significant, were elevations in somatic complaints and anxiety disorders in female HCPs. In the comparison of female HCPs and N-HCPs, the only statistically significant difference was the significantly higher

  3. A Single Sex Pheromone Receptor Determines Chemical Response Specificity of Sexual Behavior in the Silkmoth Bombyx mori

    OpenAIRE

    Sakurai, Takeshi; Mitsuno, Hidefumi; Haupt, Stephan Shuichi; Uchino, Keiro; Yokohari, Fumio; Nishioka, Takaaki; Kobayashi, Isao; Sezutsu, Hideki; Tamura, Toshiki; Kanzaki, Ryohei

    2011-01-01

    In insects and other animals, intraspecific communication between individuals of the opposite sex is mediated in part by chemical signals called sex pheromones. In most moth species, male moths rely heavily on species-specific sex pheromones emitted by female moths to identify and orient towards an appropriate mating partner among a large number of sympatric insect species. The silkmoth, Bombyx mori, utilizes the simplest possible pheromone system, in which a single pheromone component, (E, Z...

  4. Commentary Sex determination

    Indian Academy of Sciences (India)

    PRAKASH KUMAR G

    2008-01-31

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

  5. The joint return period analysis of natural disasters based on monitoring and statistical modeling of multidimensional hazard factors

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xueqin [State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875 (China); National Marine Environmental Monitoring Center, State Oceanic Administration, Dalian 116023 (China); School of Social Development and Public Policy, Beijing Normal University, Beijing 100875 (China); Li, Ning [State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875 (China); Yuan, Shuai, E-mail: syuan@nmemc.org.cn [National Marine Environmental Monitoring Center, State Oceanic Administration, Dalian 116023 (China); Xu, Ning; Shi, Wenqin; Chen, Weibin [National Marine Environmental Monitoring Center, State Oceanic Administration, Dalian 116023 (China)

    2015-12-15

    As a random event, a natural disaster has the complex occurrence mechanism. The comprehensive analysis of multiple hazard factors is important in disaster risk assessment. In order to improve the accuracy of risk analysis and forecasting, the formation mechanism of a disaster should be considered in the analysis and calculation of multi-factors. Based on the consideration of the importance and deficiencies of multivariate analysis of dust storm disasters, 91 severe dust storm disasters in Inner Mongolia from 1990 to 2013 were selected as study cases in the paper. Main hazard factors from 500-hPa atmospheric circulation system, near-surface meteorological system, and underlying surface conditions were selected to simulate and calculate the multidimensional joint return periods. After comparing the simulation results with actual dust storm events in 54 years, we found that the two-dimensional Frank Copula function showed the better fitting results at the lower tail of hazard factors and that three-dimensional Frank Copula function displayed the better fitting results at the middle and upper tails of hazard factors. However, for dust storm disasters with the short return period, three-dimensional joint return period simulation shows no obvious advantage. If the return period is longer than 10 years, it shows significant advantages in extreme value fitting. Therefore, we suggest the multivariate analysis method may be adopted in forecasting and risk analysis of serious disasters with the longer return period, such as earthquake and tsunami. Furthermore, the exploration of this method laid the foundation for the prediction and warning of other nature disasters. - Highlights: • A method to estimate the multidimensional joint return periods is presented. • 2D function allows better fitting results at the lower tail of hazard factors. • Three-dimensional simulation has obvious advantages in extreme value fitting. • Joint return periods are closer to the reality

  6. The joint return period analysis of natural disasters based on monitoring and statistical modeling of multidimensional hazard factors

    International Nuclear Information System (INIS)

    Liu, Xueqin; Li, Ning; Yuan, Shuai; Xu, Ning; Shi, Wenqin; Chen, Weibin

    2015-01-01

    As a random event, a natural disaster has the complex occurrence mechanism. The comprehensive analysis of multiple hazard factors is important in disaster risk assessment. In order to improve the accuracy of risk analysis and forecasting, the formation mechanism of a disaster should be considered in the analysis and calculation of multi-factors. Based on the consideration of the importance and deficiencies of multivariate analysis of dust storm disasters, 91 severe dust storm disasters in Inner Mongolia from 1990 to 2013 were selected as study cases in the paper. Main hazard factors from 500-hPa atmospheric circulation system, near-surface meteorological system, and underlying surface conditions were selected to simulate and calculate the multidimensional joint return periods. After comparing the simulation results with actual dust storm events in 54 years, we found that the two-dimensional Frank Copula function showed the better fitting results at the lower tail of hazard factors and that three-dimensional Frank Copula function displayed the better fitting results at the middle and upper tails of hazard factors. However, for dust storm disasters with the short return period, three-dimensional joint return period simulation shows no obvious advantage. If the return period is longer than 10 years, it shows significant advantages in extreme value fitting. Therefore, we suggest the multivariate analysis method may be adopted in forecasting and risk analysis of serious disasters with the longer return period, such as earthquake and tsunami. Furthermore, the exploration of this method laid the foundation for the prediction and warning of other nature disasters. - Highlights: • A method to estimate the multidimensional joint return periods is presented. • 2D function allows better fitting results at the lower tail of hazard factors. • Three-dimensional simulation has obvious advantages in extreme value fitting. • Joint return periods are closer to the reality

  7. Sex-specific local life-history adaptation in surface- and cave-dwelling Atlantic mollies (Poecilia mexicana).

    Science.gov (United States)

    Riesch, Rüdiger; Reznick, David N; Plath, Martin; Schlupp, Ingo

    2016-03-10

    Cavefishes have long been used as model organisms showcasing adaptive diversification, but does adaptation to caves also facilitate the evolution of reproductive isolation from surface ancestors? We raised offspring of wild-caught surface- and cave-dwelling ecotypes of the neotropical fish Poecilia mexicana to sexual maturity in a 12-month common garden experiment. Fish were raised under one of two food regimes (high vs. low), and this was crossed with differences in lighting conditions (permanent darkness vs. 12:12 h light:dark cycle) in a 2 × 2 factorial design, allowing us to elucidate potential patterns of local adaptation in life histories. Our results reveal a pattern of sex-specific local life-history adaptation: Surface molly females had the highest fitness in the treatment best resembling their habitat of origin (high food and a light:dark cycle), and suffered from almost complete reproductive failure in darkness, while cave molly females were not similarly affected in any treatment. Males of both ecotypes, on the other hand, showed only weak evidence for local adaptation. Nonetheless, local life-history adaptation in females likely contributes to ecological diversification in this system and other cave animals, further supporting the role of local adaptation due to strong divergent selection as a major force in ecological speciation.

  8. Modeling the distribution of extreme share return in Malaysia using Generalized Extreme Value (GEV) distribution

    Science.gov (United States)

    Hasan, Husna; Radi, Noor Fadhilah Ahmad; Kassim, Suraiya

    2012-05-01

    Extreme share return in Malaysia is studied. The monthly, quarterly, half yearly and yearly maximum returns are fitted to the Generalized Extreme Value (GEV) distribution. The Augmented Dickey Fuller (ADF) and Phillips Perron (PP) tests are performed to test for stationarity, while Mann-Kendall (MK) test is for the presence of monotonic trend. Maximum Likelihood Estimation (MLE) is used to estimate the parameter while L-moments estimate (LMOM) is used to initialize the MLE optimization routine for the stationary model. Likelihood ratio test is performed to determine the best model. Sherman's goodness of fit test is used to assess the quality of convergence of the GEV distribution by these monthly, quarterly, half yearly and yearly maximum. Returns levels are then estimated for prediction and planning purposes. The results show all maximum returns for all selection periods are stationary. The Mann-Kendall test indicates the existence of trend. Thus, we ought to model for non-stationary model too. Model 2, where the location parameter is increasing with time is the best for all selection intervals. Sherman's goodness of fit test shows that monthly, quarterly, half yearly and yearly maximum converge to the GEV distribution. From the results, it seems reasonable to conclude that yearly maximum is better for the convergence to the GEV distribution especially if longer records are available. Return level estimates, which is the return level (in this study return amount) that is expected to be exceeded, an average, once every t time periods starts to appear in the confidence interval of T = 50 for quarterly, half yearly and yearly maximum.

  9. An Estrogen-Responsive Module in the Ventromedial Hypothalamus Selectively Drives Sex-Specific Activity in Females

    Directory of Open Access Journals (Sweden)

    Stephanie M. Correa

    2015-01-01

    Full Text Available Estrogen-receptor alpha (ERα neurons in the ventrolateral region of the ventromedial hypothalamus (VMHVL control an array of sex-specific responses to maximize reproductive success. In females, these VMHVL neurons are believed to coordinate metabolism and reproduction. However, it remains unknown whether specific neuronal populations control distinct components of this physiological repertoire. Here, we identify a subset of ERα VMHVL neurons that promotes hormone-dependent female locomotion. Activating Nkx2-1-expressing VMHVL neurons via pharmacogenetics elicits a female-specific burst of spontaneous movement, which requires ERα and Tac1 signaling. Disrupting the development of Nkx2-1+ VMHVL neurons results in female-specific obesity, inactivity, and loss of VMHVL neurons coexpressing ERα and Tac1. Unexpectedly, two responses controlled by ERα+ neurons, fertility and brown adipose tissue thermogenesis, are unaffected. We conclude that a dedicated subset of VMHVL neurons marked by ERα, NKX2-1, and Tac1 regulates estrogen-dependent fluctuations in physical activity and constitutes one of several neuroendocrine modules that drive sex-specific responses.

  10. Modeling stock return distributions with a quantum harmonic oscillator

    Science.gov (United States)

    Ahn, K.; Choi, M. Y.; Dai, B.; Sohn, S.; Yang, B.

    2017-11-01

    We propose a quantum harmonic oscillator as a model for the market force which draws a stock return from short-run fluctuations to the long-run equilibrium. The stochastic equation governing our model is transformed into a Schrödinger equation, the solution of which features “quantized” eigenfunctions. Consequently, stock returns follow a mixed χ distribution, which describes Gaussian and non-Gaussian features. Analyzing the Financial Times Stock Exchange (FTSE) All Share Index, we demonstrate that our model outperforms traditional stochastic process models, e.g., the geometric Brownian motion and the Heston model, with smaller fitting errors and better goodness-of-fit statistics. In addition, making use of analogy, we provide an economic rationale of the physics concepts such as the eigenstate, eigenenergy, and angular frequency, which sheds light on the relationship between finance and econophysics literature.

  11. Sex-Specific Response to Stress in Populus

    Directory of Open Access Journals (Sweden)

    Nataliya V. Melnikova

    2017-10-01

    Full Text Available Populus is an effective model for genetic studies in trees. The genus Populus includes dioecious species, and the differences exhibited in males and females have been intensively studied. This review focused on the distinctions between male and female poplar and aspen plants under stress conditions, such as drought, salinity, heavy metals, and nutrient deficiency on morphological, physiological, proteome, and gene expression levels. In most studies, males of Populus species were more adaptive to the majority of the stress conditions and showed less damage, better growth, and higher photosynthetic capacity and antioxidant activity than that of the females. However, in two recent studies, no differences in non-reproductive traits were revealed for male and female trees. This discrepancy of the results could be associated with experimental design: different species and genotypes, stress conditions, types of plant materials, sampling sizes. Knowledge of sex-specific differences is crucial for basic and applied research in Populus species.

  12. Rapid evolution of the intersexual genetic correlation for fitness in Drosophila melanogaster.

    Science.gov (United States)

    Collet, Julie M; Fuentes, Sara; Hesketh, Jack; Hill, Mark S; Innocenti, Paolo; Morrow, Edward H; Fowler, Kevin; Reuter, Max

    2016-04-01

    Sexual antagonism (SA) arises when male and female phenotypes are under opposing selection, yet genetically correlated. Until resolved, antagonism limits evolution toward optimal sex-specific phenotypes. Despite its importance for sex-specific adaptation and existing theory, the dynamics of SA resolution are not well understood empirically. Here, we present data from Drosophila melanogaster, compatible with a resolution of SA. We compared two independent replicates of the "LHM " population in which SA had previously been described. Both had been maintained under identical, controlled conditions, and separated for around 200 generations. Although heritabilities of male and female fitness were similar, the intersexual genetic correlation differed significantly, being negative in one replicate (indicating SA) but close to zero in the other. Using population sequencing, we show that phenotypic differences were associated with population divergence in allele frequencies at nonrandom loci across the genome. Large frequency changes were more prevalent in the population without SA and were enriched at loci mapping to genes previously shown to have sexually antagonistic relationships between expression and fitness. Our data suggest that rapid evolution toward SA resolution has occurred in one of the populations and open avenues toward studying the genetics of SA and its resolution. © 2016 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

  13. Disregarding population specificity: its influence on the sex assessment methods from the tibia

    Czech Academy of Sciences Publication Activity Database

    Kotěrová, A.; Velemínská, J.; Dupej, J.; Brzobohatá, Hana; Pilný, A.; Brůžek, J.

    2017-01-01

    Roč. 131, č. 1 (2017), s. 251-261 ISSN 0937-9827 Institutional support: RVO:67985912 Keywords : forensic anthropology population data * sex determination * tibia * population specificity * discriminant function analysis * GAME method Subject RIV: AC - Archeology, Anthropology, Ethnology OBOR OECD: Archaeology Impact factor: 2.382, year: 2016

  14. Returning home to die: Circular labour migration and mortality in South Africa1

    Science.gov (United States)

    CLARK, SAMUEL J.; COLLINSON, MARK A.; KAHN, KATHLEEN; DRULLINGER, KYLE; TOLLMAN, STEPHEN M.

    2010-01-01

    Aim: To examine the hypothesis that circular labour migrants who become seriously ill while living away from home return to their rural homes to convalesce and possibly to die. Methods: Drawing on longitudinal data collected by the Agincourt health and demographic surveillance system in rural northeastern South Africa between 1995 and 2004, discrete time event history analysis is used to estimate the likelihood of dying for residents, short-term returning migrants, and long-term returning migrants controlling for sex, age, and historical period. Results: The annual odds of dying for short-term returning migrants are generally 1.1 to 1.9 times (depending on period, sex, and age) higher than those of residents and long-term returning migrants, and these differences are generally highly statistically significant. Further supporting the hypothesis is the fact that the proportion of HIV/TB deaths among short-term returning migrants increases dramatically as time progresses, and short-term returning migrants account for an increasing proportion of all HIV/TB deaths. Conclusions: This evidence strongly suggests that increasing numbers of circular labour migrants of prime working age are becoming ill in the urban areas where they work and coming home to be cared for and eventually to die in the rural areas where their families live. This shifts the burden of caring for them in their terminal illness to their families and the rural healthcare system with significant consequences for the distribution and allocation of health care resources. PMID:17676501

  15. A conceptual muddle: an empirical analysis of the use of 'sex' and 'gender' in 'gender-specific medicine' journals.

    Directory of Open Access Journals (Sweden)

    Anne Hammarström

    Full Text Available BACKGROUND: At the same time as there is increasing awareness in medicine of the risks of exaggerating differences between men and women, there is a growing professional movement of 'gender-specific medicine' which is directed towards analysing 'sex' and 'gender' differences. The aim of this article is to empirically explore how the concepts of 'sex' and 'gender' are used in the new field of 'gender-specific medicine', as reflected in two medical journals which are foundational to this relatively new field. METHOD AND PRINCIPAL FINDINGS: The data consist of all articles from the first issue of each journal in 2004 and an issue published three years later (n = 43. In addition, all editorials over this period were included (n = 61. Quantitative and qualitative content analyses were undertaken by the authors. Less than half of the 104 papers used the concepts of 'sex' and 'gender'. Less than 1 in 10 papers attempted any definition of the concepts. Overall, the given definitions were simple, unspecific and created dualisms between men and women. Almost all papers which used the two concepts did so interchangeably, with any possible interplay between 'sex' and gender' referred to only in six of the papers. CONCLUSION: The use of the concepts of 'sex' and gender' in 'gender-specific medicine' is conceptually muddled. The simple, dualistic and individualised use of these concepts increases the risk of essentialism and reductivist thinking. It therefore highlights the need to clarify the use of the terms 'sex' and 'gender' in medical research and to develop more effective ways of conceptualising the interplay between 'sex' and 'gender' in relation to different diseases.

  16. A comparison of approaches in fitting continuum SEDs

    International Nuclear Information System (INIS)

    Liu Yao; Wang Hong-Chi; Madlener David; Wolf Sebastian

    2013-01-01

    We present a detailed comparison of two approaches, the use of a pre-calculated database and simulated annealing (SA), for fitting the continuum spectral energy distribution (SED) of astrophysical objects whose appearance is dominated by surrounding dust. While pre-calculated databases are commonly used to model SED data, only a few studies to date employed SA due to its unclear accuracy and convergence time for this specific problem. From a methodological point of view, different approaches lead to different fitting quality, demand on computational resources and calculation time. We compare the fitting quality and computational costs of these two approaches for the task of SED fitting to provide a guide to the practitioner to find a compromise between desired accuracy and available resources. To reduce uncertainties inherent to real datasets, we introduce a reference model resembling a typical circumstellar system with 10 free parameters. We derive the SED of the reference model with our code MC3 D at 78 logarithmically distributed wavelengths in the range [0.3 μm, 1.3 mm] and use this setup to simulate SEDs for the database and SA. Our result directly demonstrates the applicability of SA in the field of SED modeling, since the algorithm regularly finds better solutions to the optimization problem than a pre-calculated database. As both methods have advantages and shortcomings, a hybrid approach is preferable. While the database provides an approximate fit and overall probability distributions for all parameters deduced using Bayesian analysis, SA can be used to improve upon the results returned by the model grid.

  17. Similar cold stress induces sex-specific neuroendocrine and working memory responses.

    Science.gov (United States)

    Solianik, Rima; Skurvydas, Albertas; Urboniene, Daiva; Eimantas, Nerijus; Daniuseviciute, Laura; Brazaitis, Marius

    2015-01-01

    Men have higher cold-induced neuroendocrine response than women; nevertheless, it is not known whether a different stress hormone rise elicits different effects on cognition during whole body cooling. The objective was to compare the effect of cold-induced neuroendocrine responses on the performance of working memory sensitive tasks between men and women. The cold stress continued until rectal temperature reached 35.5 degree C or for a maximum of 170 min. Working memory performance and stress hormone concentrations were monitored. During cold stress, body temperature variables dropped in all subjects (P < 0.001) and did not differ between sexes. Cold stress raised plasma epinephrine and serum cortisol levels only in men (P < 0.05). Cold stress adversely affected memory performance in men but not in women (P < 0.05). The present study indicated that similar moderate cold stress in men and women induces sex-specific neuroendocrine and working memory responses.

  18. Sex-specific effects of dehydroepiandrosterone (DHEA) on glucose metabolism in the CNS.

    Science.gov (United States)

    Vieira-Marques, Claudia; Arbo, Bruno Dutra; Cozer, Aline Gonçalves; Hoefel, Ana Lúcia; Cecconello, Ana Lúcia; Zanini, Priscila; Niches, Gabriela; Kucharski, Luiz Carlos; Ribeiro, Maria Flávia M

    2017-07-01

    DHEA is a neuroactive steroid, due to its modulatory actions on the central nervous system (CNS). DHEA is able to regulate neurogenesis, neurotransmitter receptors and neuronal excitability, function, survival and metabolism. The levels of DHEA decrease gradually with advancing age, and this decline has been associated with age related neuronal dysfunction and degeneration, suggesting a neuroprotective effect of endogenous DHEA. There are significant sex differences in the pathophysiology, epidemiology and clinical manifestations of many neurological diseases. The aim of this study was to determine whether DHEA can alter glucose metabolism in different structures of the CNS from male and female rats, and if this effect is sex-specific. The results showed that DHEA decreased glucose uptake in some structures (cerebral cortex and olfactory bulb) in males, but did not affect glucose uptake in females. When compared, glucose uptake in males was higher than females. DHEA enhanced the glucose oxidation in both males (cerebral cortex, olfactory bulb, hippocampus and hypothalamus) and females (cerebral cortex and olfactory bulb), in a sex-dependent manner. In males, DHEA did not affect synthesis of glycogen, however, glycogen content was increased in the cerebral cortex and olfactory bulb. DHEA modulates glucose metabolism in a tissue-, dose- and sex-dependent manner to increase glucose oxidation, which could explain the previously described neuroprotective role of this hormone in some neurodegenerative diseases. Copyright © 2016. Published by Elsevier Ltd.

  19. Sex-specific heritability of spontaneous lipid levels in an extended pedigree of Indian-origin rhesus macaques (Macaca mulatta.

    Directory of Open Access Journals (Sweden)

    Amanda Vinson

    Full Text Available The rhesus macaque is an important model for human atherosclerosis but genetic determinants of relevant phenotypes have not yet been investigated in this species. Because lipid levels are well-established and heritable risk factors for human atherosclerosis, our goal was to assess the heritability of lipoprotein cholesterol and triglyceride levels in a single, extended pedigree of 1,289 Indian-origin rhesus macaques. Additionally, because increasing evidence supports sex differences in the genetic architecture of lipid levels and lipid metabolism in humans and macaques, we also explored sex-specific heritability for all lipid measures investigated in this study. Using standard methods, we measured lipoprotein cholesterol and triglyceride levels from fasted plasma in a sample of 193 pedigreed rhesus macaques selected for membership in large, paternal half-sib cohorts, and maintained on a low-fat, low cholesterol chow diet. Employing a variance components approach, we found moderate heritability for total cholesterol (h²=0.257, P=0.032, LDL cholesterol (h²=0.252, P=0.030, and triglyceride levels (h²=0.197, P=0.034 in the full sample. However, stratification by sex (N=68 males, N=125 females revealed substantial sex-specific heritability for total cholesterol (0.644, P=0.004, females only, HDL cholesterol (0.843, P=0.0008, females only, VLDL cholesterol (0.482, P=0.018, males only, and triglyceride levels (0.705, P=0.001, males only that was obscured or absent when sexes were combined in the full sample. We conclude that genes contribute to spontaneous variation in circulating lipid levels in the Indian-origin rhesus macaque in a sex-specific manner, and that the rhesus macaque is likely to be a valuable model for sex-specific genetic effects on lipid risk factors for human atherosclerosis. These findings are a first-ever report of heritability for cholesterol levels in this species, and support the need for expanded analysis of these traits in

  20. Primate brain architecture and selection in relation to sex.

    Science.gov (United States)

    Lindenfors, Patrik; Nunn, Charles L; Barton, Robert A

    2007-05-10

    Social and competitive demands often differ between the sexes in mammals. These differing demands should be expected to produce variation in the relative sizes of various brain structures. Sexual selection on males can be predicted to influence brain components handling sensory-motor skills that are important for physical competition or neural pathways involving aggression. Conversely, because female fitness is more closely linked to ecological factors and social interactions that enable better acquisition of resources, social selection on females should select for brain components important for navigating social networks. Sexual and social selection acting on one sex could produce sexual dimorphism in brain structures, which would result in larger species averages for those same brain structures. Alternatively, sex-specific selection pressures could produce correlated effects in the other sex, resulting in larger brain structures for both males and females of a species. Data are presently unavailable for the sex-specific sizes of brain structures for anthropoid primates, but under either scenario, the effects of sexual and social selection should leave a detectable signal in average sizes of brain structures for different species. The degree of male intra-sexual selection was positively correlated with several structures involved in autonomic functions and sensory-motor skills, and in pathways relating to aggression and aggression control. The degree of male intra-sexual selection was not correlated with relative neocortex size, which instead was significantly positively correlated with female social group size, but negatively correlated with male group size. Sexual selection on males and social selection on females have exerted different effects on primate brain architecture. Species with a higher degree of male intra-sexual selection carry a neural signature of an evolutionary history centered on physical conflicts, but no traces of increased demands on

  1. Primate brain architecture and selection in relation to sex

    Directory of Open Access Journals (Sweden)

    Nunn Charles L

    2007-05-01

    Full Text Available Abstract Background Social and competitive demands often differ between the sexes in mammals. These differing demands should be expected to produce variation in the relative sizes of various brain structures. Sexual selection on males can be predicted to influence brain components handling sensory-motor skills that are important for physical competition or neural pathways involving aggression. Conversely, because female fitness is more closely linked to ecological factors and social interactions that enable better acquisition of resources, social selection on females should select for brain components important for navigating social networks. Sexual and social selection acting on one sex could produce sexual dimorphism in brain structures, which would result in larger species averages for those same brain structures. Alternatively, sex-specific selection pressures could produce correlated effects in the other sex, resulting in larger brain structures for both males and females of a species. Data are presently unavailable for the sex-specific sizes of brain structures for anthropoid primates, but under either scenario, the effects of sexual and social selection should leave a detectable signal in average sizes of brain structures for different species. Results The degree of male intra-sexual selection was positively correlated with several structures involved in autonomic functions and sensory-motor skills, and in pathways relating to aggression and aggression control. The degree of male intra-sexual selection was not correlated with relative neocortex size, which instead was significantly positively correlated with female social group size, but negatively correlated with male group size. Conclusion Sexual selection on males and social selection on females have exerted different effects on primate brain architecture. Species with a higher degree of male intra-sexual selection carry a neural signature of an evolutionary history centered on

  2. Sport-specific fitness testing and intervention for an adolescent with cerebral palsy: a case report.

    Science.gov (United States)

    Kenyon, Lisa K; Sleeper, Mark D; Tovin, Melissa M

    2010-01-01

    This case report describes the development, implementation, and outcomes of a fitness-related intervention program that addressed the sport-specific goals of an adolescent with cerebral palsy. The participant in this case was a 16-year-old African American male with spastic diplegia. The participant joined his high school wrestling team and asked to focus his physical therapy on interventions that would improve his wrestling performance. An examination was performed using the muscle power sprint test, the 10 x 5-m sprint test, strength tests, the 10-m shuttle run test, and the Gross Motor Function Measure. The intervention consisted of interval training, which focused on the demands of wrestling. Scores on all tests and measures were higher after the intervention. The outcomes of this case report seem to support the use of a fitness-related intervention program for addressing the sport-specific goals of an adolescent with cerebral palsy.

  3. Sex-specific genetic diversity is shaped by cultural factors in Inner Asian human populations.

    Science.gov (United States)

    Marchi, Nina; Hegay, Tatyana; Mennecier, Philippe; Georges, Myriam; Laurent, Romain; Whitten, Mark; Endicott, Philipp; Aldashev, Almaz; Dorzhu, Choduraa; Nasyrova, Firuza; Chichlo, Boris; Ségurel, Laure; Heyer, Evelyne

    2017-04-01

    Sex-specific genetic structures have been previously documented worldwide in humans, even though causal factors have not always clearly been identified. In this study, we investigated the impact of ethnicity, geography and social organization on the sex-specific genetic structure in Inner Asia. Furthermore, we explored the process of ethnogenesis in multiple ethnic groups. We sampled DNA in Central and Northern Asia from 39 populations of Indo-Iranian and Turkic-Mongolic native speakers. We focused on genetic data of the Y chromosome and mitochondrial DNA. First, we compared the frequencies of haplogroups to South European and East Asian populations. Then, we investigated the genetic differentiation for eight Y-STRs and the HVS1 region, and tested for the effect of geography and ethnicity on such patterns. Finally, we reconstructed the male demographic history, inferred split times and effective population sizes of different ethnic groups. Based on the haplogroup data, we observed that the Indo-Iranian- and Turkic-Mongolic-speaking populations have distinct genetic backgrounds. However, each population showed consistent mtDNA and Y chromosome haplogroups patterns. As expected in patrilocal populations, we found that the Y-STRs were more structured than the HVS1. While ethnicity strongly influenced the genetic diversity on the Y chromosome, geography better explained that of the mtDNA. Furthermore, when looking at various ethnic groups, we systematically found a genetic split time older than historical records, suggesting a cultural rather than biological process of ethnogenesis. This study highlights that, in Inner Asia, specific cultural behaviors, especially patrilineality and patrilocality, leave a detectable signature on the sex-specific genetic structure. © 2017 Wiley Periodicals, Inc.

  4. Sex-specific incidence and temporal trends in solid tumours in young people from Northern England, 1968–2005

    International Nuclear Information System (INIS)

    Magnanti, Brooke L; Dorak, M Tevfik; Parker, Louise; Craft, Alan W; James, Peter W; McNally, Richard JQ

    2008-01-01

    This study examined sex-specific patterns and temporal trends in the incidence of solid tumours in the Northern Region of England from 1968 to 2005. This updates earlier analyses from the region where sex was not considered in depth. Sex-specific analyses were carried out to determine whether sex differences might provide clues to aetiology. Details of 3576 cases, aged 0–24 years, were obtained from a specialist population-based cancer registry. There were 1843 males (886 aged 0–14 years and 957 aged 15–24 years) and 1733 females (791 aged 0–14 years and 942 aged 15–24 years). Age-standardized incidence rates (per million population) were calculated. Linear regression was used to analyze temporal trends in incidence and annual percentage changes were estimated. Analyses were stratified by sex and by age-group. There were marked differences in incidence patterns and trends between males and females and also between age-groups. For males central nervous system (CNS) tumours formed the largest proportion of under-15 cases and germ cell tumours was the largest group in the 15–24's, whilst for females CNS tumours dominated in the under-15's and carcinomas in the older group. For 0–14 year olds there were male-specific increases in the incidence of rhabdomyosarcoma (2.4% per annum; 95% CI: 0.2%–4.5%) and non-melanotic skin cancer (9.6%; 95% CI: 0.0%–19.2%) and female-specific increases for sympathetic nervous system tumours (2.2%; 95% CI: 0.4%–3.9%), gonadal germ cell tumours (8.6%; 95% CI: 4.3%–12.9%) and non-gonadal germ cell tumours (5.4%; 95% CI: 2.8%–7.9%). For 15–24 year olds, there were male-specific increases in gonadal germ cell tumours (1.9%; 95% CI: 0.3%–3.4%), non-gonadal germ cell tumours (4.4%; 95% CI: 1.1%–7.7%) and non-melanotic skin cancer (4.7%; 95% CI: 0.5%–8.9%) and female-specific increases for osteosarcoma (3.5%; 95% CI: 0.5%–6.5%), thyroid cancer (2.8%; 95% CI: 0.1%–5.6%) and melanoma (4.6%; 95% CI: 2

  5. Sex-Specific Effects of Childhood Poverty on Neurocircuitry of Processing of Emotional Cues: A Neuroimaging Study

    Directory of Open Access Journals (Sweden)

    Arash Javanbakht

    2016-12-01

    Full Text Available Background: There is accumulating evidence on the negative impacts of childhood poverty on physical and mental health. Previous work has suggested hyperactive neural response to social fear cues, as well as impairment in neural regulatory functions. However, despite differences found between males and females in stress-related and anxiety disorders, possible sex-specific effects of poverty on emotional processing have not been explored. Methods: We analyzed data from three previously reported experiments of childhood poverty effects on emotional processing and regulation, for sex-specific effects. Participants were 52 healthy Caucasian males and females, from a longitudinal cohort of poverty development study, who were recruited for examining the long-term effects of childhood poverty and stress. The three functional MRI studies included emotion regulation task, emotional face assessment task, and shifted attention emotion appraisal task. Brain activations that associated with childhood poverty previously were entered into a regression analysis with interaction of gender by childhood income-to-need ratio as the independent variable, and age and current income-to-need ratio as variables of no interest, separately for males and females. Results: Amygdala reactivity to implicitly processed fearful faces was positively correlated with childhood income-to-need in adult females but not males. On the other hand, activation in dorsolateral and ventrolateral prefrontal regions during emotion regulation by reappraisal was positively correlated with childhood income-to-need in males. Conclusion: Childhood poverty may exert sex-specific effects in adulthood as presented by hypersensitive emotional reactivity of the amygdala in females, and impaired emotion regulatory function of the prefrontal cortex in males. Results suggest further focus on sex-specific effects of childhood poverty.

  6. Sex-specific modulation of juvenile social play behavior by vasopressin and oxytocin depends on social context

    Science.gov (United States)

    Bredewold, Remco; Smith, Caroline J. W.; Dumais, Kelly M.; Veenema, Alexa H.

    2014-01-01

    We recently demonstrated that vasopressin (AVP) in the lateral septum modulates social play behavior differently in male and female juvenile rats. However, the extent to which different social contexts (i.e., exposure to an unfamiliar play partner in different environments) affect the regulation of social play remains largely unknown. Given that AVP and the closely related neuropeptide oxytocin (OXT) modulate social behavior as well as anxiety-like behavior, we hypothesized that these neuropeptides may regulate social play behavior differently in novel (novel cage) as opposed to familiar (home cage) social environments. Administration of the specific AVP V1a receptor (V1aR) antagonist (CH2)5Tyr(Me2)AVP into the lateral septum enhanced home cage social play behavior in males but reduced it in females, confirming our previous findings. These effects were context-specific because V1aR blockade did not alter novel cage social play behavior in either sex. Furthermore, social play in females was reduced by AVP in the novel cage and by OXT in the home cage. Additionally, females administered the specific OXT receptor antagonist desGly-NH2,d(CH2)5−[Tyr(Me)2,Thr4]OVT showed less social play in the novel as compared to the home cage. AVP enhanced anxiety-related behavior in males (tested on the elevated plus-maze), but failed to do so in females, suggesting that exogenous AVP alters social play and anxiety-related behavior via distinct and sex-specific mechanisms. Moreover, none of the other drug treatments that altered social play had an effect on anxiety, suggesting that these drug-induced behavioral alterations are relatively specific to social behavior. Overall, we showed that AVP and OXT systems in the lateral septum modulate social play in juvenile rats in neuropeptide-, sex- and social context-specific ways. These findings underscore the importance of considering not only sex, but also social context, in how AVP and OXT modulate social behavior. PMID:24982623

  7. Sex-specific modulation of juvenile social play behavior by vasopressin and oxytocin depends on social context

    Directory of Open Access Journals (Sweden)

    Remco eBredewold

    2014-06-01

    Full Text Available We recently demonstrated that vasopressin (AVP in the lateral septum modulates social play behavior differently in male and female juvenile rats. However, the extent to which different social contexts (i.e., exposure to an unfamiliar play partner in different environments affect the regulation of social play remains largely unknown. Given that AVP and the closely related neuropeptide oxytocin (OXT modulate social behavior as well as anxiety-like behavior, we hypothesized that these neuropeptides may regulate social play behavior differently in novel (novel cage as opposed to familiar (home cage social environments. Administration of the specific AVP V1a receptor (V1aR antagonist (CH25Tyr(Me2AVP into the lateral septum enhanced home cage social play behavior in males but reduced it in females, confirming our previous findings. These effects were context-specific because V1aR blockade did not alter novel cage social play behavior in either sex. Furthermore, social play in females was reduced by AVP in the novel cage and by OXT in the home cage. Additionally, females administered the specific OXT receptor antagonist desGly-NH2,d(CH25-[Tyr(Me2,Thr4]OVT showed less social play in the novel as compared to the home cage. AVP enhanced anxiety-related behavior in males (tested on the elevated plus-maze, but failed to do so in females, suggesting that exogenous AVP alters social play and anxiety-related behavior via distinct and sex-specific mechanisms. Moreover, none of the other drug treatments that altered social play had an effect on anxiety, suggesting that these drug-induced behavioral alterations are relatively specific to social behavior. Overall, we showed that AVP and OXT systems in the lateral septum modulate social play in juvenile rats in neuropeptide-, sex- and social context-specific ways. These findings underscore the importance of considering not only sex, but also social context, in how AVP and OXT modulate social behavior.

  8. Understanding Breaks in Flare X-Ray Spectra: Evaluation of a Cospatial Collisional Return-current Model

    Science.gov (United States)

    Alaoui, Meriem; Holman, Gordon D.

    2017-12-01

    Hard X-ray (HXR) spectral breaks are explained in terms of a one-dimensional model with a cospatial return current. We study 19 flares observed by the Ramaty High Energy Solar Spectroscopic Imager with strong spectral breaks at energies around a few deka-keV, which cannot be explained by isotropic albedo or non-uniform ionization alone. We identify these breaks at the HXR peak time, but we obtain 8 s cadence spectra of the entire impulsive phase. Electrons with an initially power-law distribution and a sharp low-energy cutoff lose energy through return-current losses until they reach the thick target, where they lose their remaining energy through collisions. Our main results are as follows. (1) The return-current collisional thick-target model provides acceptable fits for spectra with strong breaks. (2) Limits on the plasma resistivity are derived from the fitted potential drop and deduced electron-beam flux density, assuming the return current is a drift current in the ambient plasma. These resistivities are typically 2–3 orders of magnitude higher than the Spitzer resistivity at the fitted temperature, and provide a test for the adequacy of classical resistivity and the stability of the return current. (3) Using the upper limit of the low-energy cutoff, the return current is always stable to the generation of ion-acoustic and electrostatic ion-cyclotron instabilities when the electron temperature is nine times lower than the ion temperature. (4) In most cases, the return current is most likely primarily carried by runaway electrons from the tail of the thermal distribution rather than by the bulk drifting thermal electrons. For these cases, anomalous resistivity is not required.

  9. Region-specific associations between sex, social status, and oxytocin receptor density in the brains of eusocial rodents.

    Science.gov (United States)

    Mooney, S J; Coen, C W; Holmes, M M; Beery, A K

    2015-09-10

    Naturally occurring variations in neuropeptide receptor distributions in the brain contribute to numerous mammalian social behaviors. In naked mole-rats, which live in large social groups and exhibit remarkable reproductive skew, colony-related social behaviors vary with reproductive status. Here we examined whether variation in social status is associated with variations in the location and/or density of oxytocin binding in this species. Autoradiography was performed to assess forebrain oxytocin receptor (OTR) densities in breeding and non-breeding naked mole-rats of both sexes. Overall, males exhibited higher OTR binding in the medial amygdala in comparison to females. While there were no main effects of reproductive status in any region, a sex difference in OTR binding in the nucleus accumbens was mediated by status. Specifically, breeding males tended to have more OTR binding than breeding females in the nucleus accumbens, while no sex difference was observed in subordinates. These effects suggest that oxytocin may act in a sex- and region-specific way that corresponds to reproductive status and associated social behaviors. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

  10. Sex-specific metabolic interactions between liver and adipose tissue in MCD diet-induced non-alcoholic fatty liver disease.

    Science.gov (United States)

    Lee, Yun-Hee; Kim, Sou Hyun; Kim, Sang-Nam; Kwon, Hyun-Jung; Kim, Jeong-Dong; Oh, Ji Youn; Jung, Young-Suk

    2016-07-26

    Higher susceptibility to metabolic disease in male exemplifies the importance of sexual dimorphism in pathogenesis. We hypothesized that the higher incidence of non-alcoholic fatty liver disease in males involves sex-specific metabolic interactions between liver and adipose tissue. In the present study, we used a methionine-choline deficient (MCD) diet-induced fatty liver mouse model to investigate sex differences in the metabolic response of the liver and adipose tissue. After 2 weeks on an MCD-diet, fatty liver was induced in a sex-specific manner, affecting male mice more severely than females. The MCD-diet increased lipolytic enzymes in the gonadal white adipose tissue (gWAT) of male mice, whereas it increased expression of uncoupling protein 1 and other brown adipocyte markers in the gWAT of female mice. Moreover, gWAT from female mice demonstrated higher levels of oxygen consumption and mitochondrial content compared to gWAT from male mice. FGF21 expression was increased in liver tissue by the MCD diet, and the degree of upregulation was significantly higher in the livers of female mice. The endocrine effect of FGF21 was responsible, in part, for the sex-specific browning of gonadal white adipose tissue. Collectively, these data demonstrated that distinctively female-specific browning of white adipose tissue aids in protecting female mice against MCD diet-induced fatty liver disease.

  11. Impact of CrossFit-Related Spinal Injuries.

    Science.gov (United States)

    Hopkins, Benjamin S; Cloney, Michael B; Kesavabhotla, Kartik; Yamaguchi, Jonathon; Smith, Zachary A; Koski, Tyler R; Hsu, Wellington K; Dahdaleh, Nader S

    2017-11-16

    Exercise-related injuries (ERIs) are a common cause of nonfatal emergency department and hospital visits. CrossFit is a high-intensity workout regimen whose popularity has grown rapidly. However, ERIs due to CrossFit remained under investigated. All patients who presented to the main hospital at a major academic center complaining of an injury sustained performing CrossFit between June 2010 and June 2016 were identified. Injuries were classified by anatomical location (eg, knee, spine). For patients with spinal injuries, data were collected including age, sex, body mass index (BMI), CrossFit experience level, symptom duration, type of symptoms, type of clinic presentation, cause of injury, objective neurological examination findings, imaging type, number of clinic visits, and treatments prescribed. Four hundred ninety-eight patients with 523 CrossFit-related injuries were identified. Spine injuries were the most common injuries identified, accounting for 20.9%. Among spine injuries, the most common location of injury was the lumbar spine (83.1%). Average symptom duration was 6.4 months ± 15.1, and radicular complaints were the most common symptom (53%). A total of 30 (32%) patients had positive findings on neurologic examination. Six patients (6.7%) required surgical intervention for treatment after failing an average of 9.66 months of conservative treatment. There was no difference in age, sex, BMI, or duration of symptoms of patients requiring surgery with those who did not. CrossFit is a popular, high-intensity style workout with the potential to injure its participants. Spine injuries were the most common type of injury observed and frequently required surgical intervention.

  12. Sex-specific phenotypes of hyperthyroidism and hypothyroidism in mice.

    Science.gov (United States)

    Rakov, Helena; Engels, Kathrin; Hönes, Georg Sebastian; Strucksberg, Karl-Heinz; Moeller, Lars Christian; Köhrle, Josef; Zwanziger, Denise; Führer, Dagmar

    2016-01-01

    Thyroid dysfunction is more common in the female population, however, the impact of sex on disease characteristics has rarely been addressed. Using a murine model, we asked whether sex has an influence on phenotypes, thyroid hormone status, and thyroid hormone tissue response in hyper- and hypothyroidism. Hypo- and hyperthyroidism were induced in 5-month-old female and male wildtype C57BL/6N mice, by LoI/MMI/ClO4 (-) or T4 i.p. treatment over 7 weeks, and control animals underwent sham treatment (N = 8 animals/sex/treatment). Animals were investigated for impact of sex on body weight, food and water intake, body temperature, heart rate, behaviour (locomotor activity, motor coordination, and strength), liver function, serum thyroid hormone status, and cellular TH effects on gene expression in brown adipose tissue, heart, and liver. Male and female mice showed significant differences in behavioural, functional, metabolic, biochemical, and molecular traits of hyper- and hypothyroidism. Hyperthyroidism resulted in increased locomotor activity in female mice but decreased muscle strength and motor coordination preferably in male animals. Hypothyroidism led to increased water intake in male but not female mice and significantly higher serum cholesterol in male mice. Natural sex differences in body temperature, body weight gain, food and water intake were preserved under hyperthyroid conditions. In contrast, natural sex differences in heart rate disappeared with TH excess and deprivation. The variations of hyper- or hypothyroid traits of male and female mice were not explained by classical T3/T4 serum state. TH serum concentrations were significantly increased in female mice under hyperthyroidism, but no sex differences were found under eu- or hypothyroid conditions. Interestingly, analysis of expression of TH target genes and TH transporters revealed little sex dependency in heart, while sex differences in target genes were present in liver and brown adipose tissue

  13. Functional Specificity and Sex Differences in the Neural Circuits Supporting the Inhibition of Automatic Imitation.

    Science.gov (United States)

    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.

  14. Return to golf after spine surgery.

    Science.gov (United States)

    Abla, Adib A; Maroon, Joseph C; Lochhead, Richard; Sonntag, Volker K H; Maroon, Adara; Field, Melvin

    2011-01-01

    no published evidence indicates when patients can resume golfing after spine surgery. The objective of this study is to provide data from surveys sent to spine surgeons. a survey of North American Spine Society members was undertaken querying the suggested timing of return to golf. Of 1000 spine surgeons surveyed, 523 responded (52.3%). The timing of recommended return to golf and the reasons were questioned for college/professional athletes and avid and recreational golfers of both sexes. Responses were tallied for lumbar laminectomy, lumbar microdiscectomy, lumbar fusion, and anterior cervical discectomy with fusion. the most common recommended time for return to golf was 4-8 weeks after lumbar laminectomy and lumbar microdiscectomy, 2-3 months after anterior cervical fusion, and 6 months after lumbar fusion. The results showed a statistically significant increase in the recommended time to resume golf after lumbar fusion than after cervical fusion in all patients (p golf after spine surgery depends on many variables, including the general well-being of patients in terms of pain control and comfort when golfing. This survey serves as a guide that can assist medical practitioners in telling patients the average times recommended by surgeons across North America regarding return to golf after spine surgery.

  15. Characteristics of donors who do or do not return to give blood and barriers to their return

    Science.gov (United States)

    Wevers, Anne; Wigboldus, Daniël H.J.; de Kort, Wim L.A.M.; van Baaren, Rick; Veldhuizen, Ingrid J.T.

    2014-01-01

    Background In the Netherlands about 50% of whole blood donors return to give blood after an invitation to donate. This study aimed to investigate the characteristics of donor return behaviour and to gain insight into the barriers to blood donation reported by the donors themselves. Materials and methods A total of 4,901 whole blood donors were invited to donate in week 39 of 2009. Barriers mentioned by donors who informed the blood bank for not donating were registered for 1 month. Logistic regression analyses assessed relevant characteristics of return behaviour, such as age and blood type, in men and women separately. Results Of the invited donors, 55% returned to give a donation, whereas 45% did not return. Male donors were more likely to return when they were older, had a higher previous return rate and had no past deferrals. The same pattern was found among women, but was less strong. The main barriers were: time constraints (35%), preference to postpone donation due to general physical problems although being eligible to donate (29%), and being ineligible to donate due to medical deferral criteria (9%). Discussion Specific donor characteristics are associated with return behaviour. Not donating due to time constraints could mean that donors do not feel the urgency of donating blood. Interventions targeted to increase commitment among specific donor groups should be tested further. PMID:23522891

  16. `Sex' – It's not only Women's Work: A Case for Refocusing on the Functional Role that Sex Plays in Work for both Women and Men

    OpenAIRE

    Uretsky, Elanah

    2014-01-01

    Mention of the term sex work often invokes images of marginalized women at risk for HIV infection. Such images, however, are counterintuitive to the functional role intended by the movement that spawned use of the terms `sex work' and `sex worker'. This article looks at the sexual practices of men in urban China to argue for a return to a functional definition of `sex work', which was originally meant to legitimize the role sex plays in work. The progenitors of this movement intended to use `...

  17. Effects of Pregnancy on the Army Physical Fitness Test

    National Research Council Canada - National Science Library

    Usher, Stacy

    2003-01-01

    The purpose of this study was to determine the actual and perceived amount of time needed for the postpartum soldier to return to pre-pregnancy fitness condition as evidenced by APFT scores before and after...

  18. Sex-specific vitellogenin production in immature rainbow trout

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, D.B.; Williams, D.E.

    1999-10-01

    Many xenobiotics interact with hormone systems of animals, potentially leading to a phenomenon commonly called endocrine disruption. Much attention has focused on steroid hormone systems and corresponding receptor proteins, particularly estrogens. Vitellogenin (Vg) was measured in sexually immature rainbow trout (Oncorhynchus mykiss) exposed to 17{beta}-estradiol (E{sub 2}) in the diet. Mixed-sex populations of trout aged 3, 6, 12, or 18 months were maintained separately and fed E{sub 2} at 0.05 or 2.5 mg/kg for 7d. Females fed E{sub 2} at 0.05 mg/kg consistently produced three- to fourfold greater amounts of Vg than similarly aged males. Age- and sex-matched fish fed E{sub 2} at 2.5 mg/kg produced equivalent amounts of Vg. Sex differences in Vg production were apparent only at a dose of E{sub 2} (0.05 mg/kg) that results in submaximal Vg induction. Their results document the importance of considering the sex of juvenile fish when using Vg production as a marker of xenoestrogen exposure.

  19. Screening of Genes Specifically Expressed in Males of Fenneropenaeus chinensis and Their Potential as Sex Markers

    Directory of Open Access Journals (Sweden)

    Shihao Li

    2013-01-01

    Full Text Available The androgenic gland (AG, playing an important role in sex differentiation of male crustacean, is a target candidate to understand the mechanism of male development and to mine male-specific sex markers. An SSH library (designated as male reproduction-related tissues—SSH library, MRT-SSH library for short was constructed using cDNA from tissues located at the basal part of the 5th pereiopods, including AG and part of spermatophore sac, as tester, and the cDNA from the basal part of the 4th pereiopods of these male shrimp as driver. 402 ESTs from the SSH library were sequenced and assembled into 48 contigs and 104 singlets. Twelve contigs and 14 singlets were identified as known genes. The proteins encoded by the identified genes were categorized, according to their proposed functions, into neuropeptide hormone and hormone transporter, RNA posttranscriptional regulation, translation, cell growth and death, metabolism, genetic information processing, signal transduction/transport, or immunity-related proteins. Eleven highly expressed contigs in the SSH library were selected for validation of the MRT-SSH library and screening sex markers of shrimp. One contig, specifically expressed in male shrimp, had a potential to be developed as a transcriptomic sex marker in shrimp.

  20. Sex-specific effects of yolk testosterone on survival, begging and growth of zebra finches

    NARCIS (Netherlands)

    von Engelhardt, N; Carere, C; Dijkstra, C; Groothuis, TGG

    2006-01-01

    Yolk androgens affect offspring hatching, begging, growth and survival in many bird species. If these effects are sex-specific, yolk androgen deposition may constitute a mechanism for differential investment in male and female offspring. We tested this hypothesis in zebra finches. In this species,

  1. Are elder siblings helpers or competitors? Antagonistic fitness effects of sibling interactions in humans

    Science.gov (United States)

    Nitsch, Aïda; Faurie, Charlotte; Lummaa, Virpi

    2013-01-01

    Determining the fitness consequences of sibling interactions is pivotal for understanding the evolution of family living, but studies investigating them across lifetime are lacking. We used a large demographic dataset on preindustrial humans from Finland to study the effect of elder siblings on key life-history traits. The presence of elder siblings improved the chances of younger siblings surviving to sexual maturity, suggesting that despite a competition for parental resources, they may help rearing their younger siblings. After reaching sexual maturity however, same-sex elder siblings' presence was associated with reduced reproductive success in the focal individual, indicating the existence of competition among same-sex siblings. Overall, lifetime fitness was reduced by same-sex elder siblings' presence and increased by opposite-sex elder siblings' presence. Our study shows opposite effects of sibling interactions depending on the life-history stage, and highlights the need for using long-term fitness measures to understand the selection pressures acting on sibling interactions. PMID:23173210

  2. Effects of Pregnancy on the Army Physical Fitness Test

    National Research Council Canada - National Science Library

    Usher, Stacy

    2003-01-01

    The purpose of this study was to determine the actual and perceived amount of time needed for the postpartum soldier to return to pre-pregnancy fitness condition as evidenced by APFT scores before and after pregnancy...

  3. Measurement Noninvariance of Safer Sex Self-Efficacy Between Heterosexual and Sexual Minority Black Youth.

    Science.gov (United States)

    Gerke, Donald; Budd, Elizabeth L; Plax, Kathryn

    2016-01-01

    Black and lesbian, gay, bisexual, or questioning (LGBQ) youth in the United States are disproportionately affected by HIV and other sexually transmitted diseases (STDs). Although self-efficacy is strongly, positively associated with safer sex behaviors, no studies have examined the validity of a safer sex self-efficacy scale used by many federally funded HIV/STD prevention programs. This study aims to test factor validity of the Sexual Self-Efficacy Scale by using confirmatory factor analysis (CFA) to determine if scale validity varies between heterosexual and LGBQ Black youth. The study uses cross-sectional data collected through baseline surveys with 226 Black youth (15 to 24 years) enrolled in community-based HIV-prevention programs. Participants use a 4-point Likert-type scale to report their confidence in performing 6 healthy sexual behaviors. CFAs are conducted on 2 factor structures of the scale. Using the best-fitting model, the scale is tested for measurement invariance between the 2 groups. A single-factor model with correlated errors of condom-specific items fits the sample well and, when tested with the heterosexual group, the model demonstrates good fit. However, when tested with the LGBQ group, the same model yields poor fit, indicating factorial noninvariance between the groups. The Sexual Self-Efficacy Scale does not perform equally well among Black heterosexual and LGBQ youth. Study findings suggest additional research is needed to inform development of measures for safer sex self-efficacy among Black LGBQ youth to ensure validity of conceptual understanding and to accurately assess effectiveness of HIV/STD prevention interventions among this population.

  4. Anti-aging drugs reduce hypothalamic inflammation in a sex-specific manner.

    Science.gov (United States)

    Sadagurski, Marianna; Cady, Gillian; Miller, Richard A

    2017-08-01

    Aging leads to hypothalamic inflammation, but does so more slowly in mice whose lifespan has been extended by mutations that affect GH/IGF-1 signals. Early-life exposure to GH by injection, or to nutrient restriction in the first 3 weeks of life, also modulate both lifespan and the pace of hypothalamic inflammation. Three drugs extend lifespan of UM-HET3 mice in a sex-specific way: acarbose (ACA), 17-α-estradiol (17αE2), and nordihydroguaiaretic acid (NDGA), with more dramatic longevity increases in males in each case. In this study, we examined the effect of these anti-aging drugs on neuro-inflammation in hypothalamus and hippocampus. We found that age-associated hypothalamic inflammation is reduced in males but not in females at 12 months of age by ACA and 17αE2 and at 22 months of age in NDGA-treated mice. The three drugs blocked indices of hypothalamic reactive gliosis associated with aging, such as Iba-1-positive microglia and GFAP-positive astrocytes, as well as age-associated overproduction of TNF-α. This effect was not observed in drug-treated female mice or in the hippocampus of the drug-treated animals. On the other hand, caloric restriction (CR; an intervention that extends the lifespan in both sexes) significantly reduced hypothalamic microglia and TNF-α in both sexes at 12 months of age. Together, these results suggest that the extent of drug-induced changes in hypothalamic inflammatory processes is sexually dimorphic in a pattern that parallels the effects of these agents on mouse longevity and that mimics the changes seen, in both sexes, of long-lived nutrient restricted or mutant mice. © 2017 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  5. The condom imperative in anal sex - one size may not fit all: a qualitative descriptive study of men who have sex with men.

    Science.gov (United States)

    Neville, Stephen; Adams, Jeffery; Moorley, Calvin; Jackson, Debra

    2016-12-01

    To explore men who have sex with men's views about condom use when having anal intercourse. Internationally, health promotion campaigns use behavioural change strategies to support men who have sex with men to always use condoms when having anal sex with other men. The health promotion message given to this group is consistent and explicitly stated that 'use a condom every time for anal sex regardless of relationship status'. Qualitative analysis of data from a cohort of New Zealand men who have sex with men. A total of 960 useable questionnaires were completed: 571 online and 389 in hard copy. Qualitative data were analysed using a thematic data analytic process. Three themes relating to condom use in men who have sex with men were identified. These are as follows: 'Safer sex is good sex', 'Condom use is good but …' and 'I use condoms sometimes'. The range of responses towards condom use for anal sex in men who have sex with men in our sample reveal this as a complex public health issue, with not all men who have sex with men willing to consistently use condoms. It is important that nurses do not assume that all men who have sex with men are willing to use condoms for anal sex, and should create opportunities for men who have sex with men to raise any concerns about the use of condoms. In this way, nurses can assist in providing information that may help men who have sex with men to make decisions that will minimise risk of contracting infections associated with sexual activity. © 2016 John Wiley & Sons Ltd.

  6. Age and sex specific variation in hematological and serum biochemical parameters of Beluga (Huso huso Linnaeus, 1758

    Directory of Open Access Journals (Sweden)

    Reza Akrami

    2013-05-01

    Full Text Available In the present study, the age- and sex-specific changes of various haematological and blood serum biochemical blood parameters of Beluga (Huso huso were investigated. Blood samples were collected from 4-, 6-, 7-, and 8-year-old beluga (n = 7 for each sex and age. The specimens were fed at a rate of 0.5-3% body weight per day. AST and LDH levels in 7- and 8-year-old fish of both sexes were significantly higher (P<0.05 than those in 4- and 6-year-old individuals. The mean ALT were significantly different (P<0.05 in both sexes of 4-, 6-, and 7-year-old sturgeon. However, the 6-, 7-, and 8-year-old female sturgeon had higher ALP levels (P<0.05. Additionally, mean RBC, PCV, and Hb values were significantly higher (P<0.05 in 7- and 8-year-old females and males than the others. Two-tailed Pearson’s correlation between the biochemical and haematological parameters obtained for beluga sturgeon indicated significant positive correlations between AST and ALP, AST and LDH, ALP and LDH, RBC and Hb, RBC and PCV, Hb and PCV, MCH and MCHC, and MCV and MCH. However, significant negative correlations were found between RBC and MCV and MCH. These results suggest that the blood parameters of beluga are influenced by age- and sex-specific factors.

  7. Fitness costs of polygyny in female Pied Flycatchers Ficedula hypoleuca

    NARCIS (Netherlands)

    Both, C.

    2002-01-01

    Variance in mating systems can only be understood if the fitness consequences of the available options are known for both sexes. In Pied Flycatchers Ficedula hypoleuca it has for long been suggested that females pairing with already mated males pay a fitness cost, and it is still debated why females

  8. Sex-specific features of emphysema among current and former smokers with COPD.

    Science.gov (United States)

    Hardin, Megan; Foreman, Marilyn; Dransfield, Mark T; Hansel, Nadia; Han, MeiLan K; Cho, Michael H; Bhatt, Surya P; Ramsdell, Joe; Lynch, David; Curtis, Jeffrey L; Silverman, Edwin K; Washko, George; DeMeo, Dawn

    2016-01-01

    Recent studies suggest that males with chronic obstructive pulmonary disease (COPD) have more emphysema than females. It is not known if these differences persist across degrees of COPD severity. Our aim was to identify sex-specific differences in quantitative emphysema within COPD subgroups based on COPD severity.We included non-Hispanic white and African-American subjects from the COPDGene study with at least 10 pack-years of smoking and COPD Global Initiative for Chronic Obstructive Lung Disease (GOLD) spirometry grade II or greater. We examined sex-specific differences in log-transformed emphysema (log per cent low-attenuation area (%LAA)) by GOLD spirometry grade among subjects with early-onset COPD (25% emphysema).Compared with females, males had higher log %LAA: overall (1.97±1.4 versus 1.69±1.6, β=0.32 (0.04), p=1.34×10(-14)), and among non-Hispanic white (p=8.37×10(-14)) and African-American subjects (p=0.002). Females with early-onset COPD, severe emphysema and GOLD grade IV COPD had similar emphysema as males, but markedly fewer pack-years smoking (early-onset, p=0.01; severe emphysema and GOLD grade IV, psmokers with COPD who are particularly susceptible to parenchymal destruction. Copyright ©ERS 2016.

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

    Science.gov (United States)

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

    1998-01-01

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

  10. Sex-specific differences in the presenting location of a first venous thromboembolism.

    Science.gov (United States)

    Scheres, L J J; Brekelmans, M P A; Beenen, L F M; Büller, H R; Cannegieter, S C; Middeldorp, S

    2017-07-01

    Essentials Whether the location of venous thromboembolism (VTE) differs between the sexes is not known. Pulmonary embolism as presenting location was relatively more common in women than in men. The difference was consistent among age groups and most prominent in unprovoked VTE. The underlying mechanism remains to be elucidated. Background The risk of venous thromboembolism (VTE) differs between men and women. Some risk factors seem to influence the presenting location of VTE. Sex-specific differences in the presenting VTE location have not been studied extensively. Methods We analyzed data from the MEGA case-control study and the Hokusai-VTE study, and used published data from the RIETE registry. Data from patients with a symptomatic first VTE were included (MEGA, n = 4953; Hokusai-VTE, n = 6720; RIETE, n = 40 028). Distributions of deep vein thrombosis (DVT), pulmonary embolism (PE) and combined DVT and PE as the presenting VTE location were calculated for men and women, and presented as proportions with 95% confidence intervals (CIs). Sex-specific differences were explored for different age categories and for unprovoked and provoked events. Results In the MEGA study, PE was the presenting location in 35.5% of women and in 29.5% of men with VTE (difference 6.0%, 95% CI 3.4-8.6). In the Hokusai-VTE study, these proportions were 35.1% for women and 25.2% for men (difference 10.0%, 95% CI 7.8-12.2). In the RIETE registry, PE (with or without DVT) was also observed more often as the presenting location in women (53.3%) than in men (47.7%), with a difference of 5.6% (95% CI 4.7-6.6). The observed higher proportion of PE as the presenting location in women was present in all age groups and was most prominent among unprovoked VTE events. Conclusions In three large studies, the distribution of the presenting VTE location differed consistently between the sexes, whereby PE was more often the primary location of presentation in women than in men. © 2017

  11. Coronary calcium predicts events better with absolute calcium scores than age-sex-race/ethnicity percentiles: MESA (Multi-Ethnic Study of Atherosclerosis).

    Science.gov (United States)

    Budoff, Matthew J; Nasir, Khurram; McClelland, Robyn L; Detrano, Robert; Wong, Nathan; Blumenthal, Roger S; Kondos, George; Kronmal, Richard A

    2009-01-27

    In this study, we aimed to establish whether age-sex-specific percentiles of coronary artery calcium (CAC) predict cardiovascular outcomes better than the actual (absolute) CAC score. The presence and extent of CAC correlates with the overall magnitude of coronary atherosclerotic plaque burden and with the development of subsequent coronary events. MESA (Multi-Ethnic Study of Atherosclerosis) is a prospective cohort study of 6,814 asymptomatic participants followed for coronary heart disease (CHD) events including myocardial infarction, angina, resuscitated cardiac arrest, or CHD death. Time to incident CHD was modeled with Cox regression, and we compared models with percentiles based on age, sex, and/or race/ethnicity to categories commonly used (0, 1 to 100, 101 to 400, 400+ Agatston units). There were 163 (2.4%) incident CHD events (median follow-up 3.75 years). Expressing CAC in terms of age- and sex-specific percentiles had significantly lower area under the receiver-operating characteristic curve (AUC) than when using absolute scores (women: AUC 0.73 versus 0.76, p = 0.044; men: AUC 0.73 versus 0.77, p better model fit with the overall score. Both methods robustly predicted events (>90th percentile associated with a hazard ratio [HR] of 16.4, 95% confidence interval [CI]: 9.30 to 28.9, and score >400 associated with HR of 20.6, 95% CI: 11.8 to 36.0). Within groups based on age-, sex-, and race/ethnicity-specific percentiles there remains a clear trend of increasing risk across levels of the absolute CAC groups. In contrast, once absolute CAC category is fixed, there is no increasing trend across levels of age-, sex-, and race/ethnicity-specific categories. Patients with low absolute scores are low-risk, regardless of age-, sex-, and race/ethnicity-specific percentile rank. Persons with an absolute CAC score of >400 are high risk, regardless of percentile rank. Using absolute CAC in standard groups performed better than age-, sex-, and race/ethnicity-specific

  12. Conservation and Sex-Specific Splicing of the transformer Gene in the Calliphorids Cochliomyia hominivorax, Cochliomyia macellaria and Lucilia sericata

    Science.gov (United States)

    Li, Fang; Vensko, Steven P.; Belikoff, Esther J.; Scott, Maxwell J.

    2013-01-01

    Transformer (TRA) promotes female development in several dipteran species including the Australian sheep blowfly Lucilia cuprina, the Mediterranean fruit fly, housefly and Drosophila melanogaster. tra transcripts are sex-specifically spliced such that only the female form encodes full length functional protein. The presence of six predicted TRA/TRA2 binding sites in the sex-specific female intron of the L. cuprina gene suggested that tra splicing is auto-regulated as in medfly and housefly. With the aim of identifying conserved motifs that may play a role in tra sex-specific splicing, here we have isolated and characterized the tra gene from three additional blowfly species, L. sericata, Cochliomyia hominivorax and C. macellaria. The blowfly adult male and female transcripts differ in the choice of splice donor site in the first intron, with males using a site downstream of the site used in females. The tra genes all contain a single TRA/TRA2 site in the male exon and a cluster of four to five sites in the male intron. However, overall the sex-specific intron sequences are poorly conserved in closely related blowflies. The most conserved regions are around the exon/intron junctions, the 3′ end of the intron and near the cluster of TRA/TRA2 sites. We propose a model for sex specific regulation of tra splicing that incorporates the conserved features identified in this study. In L. sericata embryos, the male tra transcript was first detected at around the time of cellular blastoderm formation. RNAi experiments showed that tra is required for female development in L. sericata and C. macellaria. The isolation of the tra gene from the New World screwworm fly C. hominivorax, a major livestock pest, will facilitate the development of a “male-only” strain for genetic control programs. PMID:23409170

  13. Influence of personality, age, sex, and estrous state on chimpanzee problem-solving success

    DEFF Research Database (Denmark)

    Hopper, Lydia M; Price, Sara A; Freeman, Hani D

    2014-01-01

    Despite the importance of individual problem solvers for group- and individual-level fitness, the correlates of individual problem-solving success are still an open topic of investigation. In addition to demographic factors, such as age or sex, certain personality dimensions have also been revealed...... as reliable correlates of problem-solving by animals. Such correlates, however, have been little-studied in chimpanzees. To empirically test the influence of age, sex, estrous state, and different personality factors on chimpanzee problem-solving, we individually tested 36 captive chimpanzees with two novel...... with the luteinizing hormone surge of a female's estrous cycle) and again when it was detumescent. Although we found no correlation between the chimpanzees' success with either puzzle and their age or sex, the chimpanzees' personality ratings did correlate with responses to the novel foraging puzzles. Specifically...

  14. Mitochondrial DNA paradox: sex-specific genetic structure in a marine mussel – despite maternal inheritance and passive dispersal

    Directory of Open Access Journals (Sweden)

    Teske Peter R

    2012-06-01

    Full Text Available Abstract Background When genetic structure is identified using mitochondrial DNA (mtDNA, but no structure is identified using biparentally-inherited nuclear DNA, the discordance is often attributed to differences in dispersal potential between the sexes. Results We sampled the intertidal rocky shore mussel Perna perna in a South African bay and along the nearby open coast, and sequenced maternally-inherited mtDNA (there is no evidence for paternally-inherited mtDNA in this species and a biparentally-inherited marker. By treating males and females as different populations, we identified significant genetic structure on the basis of mtDNA data in the females only. Conclusions This is the first study to report sex-specific differences in genetic structure based on matrilineally-inherited mtDNA in a passively dispersing species that lacks social structure or sexual dimorphism. The observed pattern most likely stems from females being more vulnerable to selection in habitats from which they did not originate, which also manifests itself in a male-biased sex ratio. Our results have three important implications for the interpretation of population genetic data. First, even when mtDNA is inherited exclusively in the female line, it also contains information about males. For that reason, using it to identify sex-specific differences in genetic structure by contrasting it with biparentally-inherited markers is problematic. Second, the fact that sex-specific differences were found in a passively dispersing species in which sex-biased dispersal is unlikely highlights the fact that significant genetic structure is not necessarily a function of low dispersal potential or physical barriers. Third, even though mtDNA is typically used to study historical demographic processes, it also contains information about contemporary processes. Higher survival rates of males in non-native habitats can erase the genetic structure present in their mothers within a single

  15. Sex-specific differences in hyperoxic lung injury in mice: Implications for acute and chronic lung disease in humans

    Energy Technology Data Exchange (ETDEWEB)

    Lingappan, Krithika, E-mail: lingappa@bcm.edu [Department of Pediatrics, Section of Neonatology, Texas Children' s Hospital, Baylor College of Medicine, 1102 Bates Avenue, MC: FC530.01, Houston, TX 77030 (United States); Jiang, Weiwu; Wang, Lihua; Couroucli, Xanthi I. [Department of Pediatrics, Section of Neonatology, Texas Children' s Hospital, Baylor College of Medicine, 1102 Bates Avenue, MC: FC530.01, Houston, TX 77030 (United States); Barrios, Roberto [Department of Pathology and Genomic Medicine, The Methodist Hospital Physician Organization, 6565 Fannin Street, Suite M227, Houston, TX 77030 (United States); Moorthy, Bhagavatula [Department of Pediatrics, Section of Neonatology, Texas Children' s Hospital, Baylor College of Medicine, 1102 Bates Avenue, MC: FC530.01, Houston, TX 77030 (United States)

    2013-10-15

    Sex-specific differences in pulmonary morbidity in humans are well documented. Hyperoxia contributes to lung injury in experimental animals and humans. The mechanisms responsible for sex differences in the susceptibility towards hyperoxic lung injury remain largely unknown. In this investigation, we tested the hypothesis that mice will display sex-specific differences in hyperoxic lung injury. Eight week-old male and female mice (C57BL/6J) were exposed to 72 h of hyperoxia (FiO{sub 2} > 0.95). After exposure to hyperoxia, lung injury, levels of 8-iso-prostaglandin F{sub 2} alpha (8-iso-PGF 2α) (LC–MS/MS), apoptosis (TUNEL) and inflammatory markers (suspension bead array) were determined. Cytochrome P450 (CYP)1A expression in the lung was assessed using immunohistochemistry and western blotting. After exposure to hyperoxia, males showed greater lung injury, neutrophil infiltration and apoptosis, compared to air-breathing controls than females. Pulmonary 8-iso-PGF 2α levels were higher in males than females after hyperoxia exposure. Sexually dimorphic increases in levels of IL-6 (F > M) and VEGF (M > F) in the lungs were also observed. CYP1A1 expression in the lung was higher in female mice compared to males under hyperoxic conditions. Overall, our results support the hypothesis that male mice are more susceptible than females to hyperoxic lung injury and that differences in inflammatory and oxidative stress markers contribute to these sex-specific dimorphic effects. In conclusion, this paper describes the establishment of an animal model that shows sex differences in hyperoxic lung injury in a temporal manner and thus has important implications for lung diseases mediated by hyperoxia in humans. - Highlights: • Male mice were more susceptible to hyperoxic lung injury than females. • Sex differences in inflammatory markers were observed. • CYP1A expression was higher in females after hyperoxia exposure.

  16. Sex-specific differences in hyperoxic lung injury in mice: Implications for acute and chronic lung disease in humans

    International Nuclear Information System (INIS)

    Lingappan, Krithika; Jiang, Weiwu; Wang, Lihua; Couroucli, Xanthi I.; Barrios, Roberto; Moorthy, Bhagavatula

    2013-01-01

    Sex-specific differences in pulmonary morbidity in humans are well documented. Hyperoxia contributes to lung injury in experimental animals and humans. The mechanisms responsible for sex differences in the susceptibility towards hyperoxic lung injury remain largely unknown. In this investigation, we tested the hypothesis that mice will display sex-specific differences in hyperoxic lung injury. Eight week-old male and female mice (C57BL/6J) were exposed to 72 h of hyperoxia (FiO 2 > 0.95). After exposure to hyperoxia, lung injury, levels of 8-iso-prostaglandin F 2 alpha (8-iso-PGF 2α) (LC–MS/MS), apoptosis (TUNEL) and inflammatory markers (suspension bead array) were determined. Cytochrome P450 (CYP)1A expression in the lung was assessed using immunohistochemistry and western blotting. After exposure to hyperoxia, males showed greater lung injury, neutrophil infiltration and apoptosis, compared to air-breathing controls than females. Pulmonary 8-iso-PGF 2α levels were higher in males than females after hyperoxia exposure. Sexually dimorphic increases in levels of IL-6 (F > M) and VEGF (M > F) in the lungs were also observed. CYP1A1 expression in the lung was higher in female mice compared to males under hyperoxic conditions. Overall, our results support the hypothesis that male mice are more susceptible than females to hyperoxic lung injury and that differences in inflammatory and oxidative stress markers contribute to these sex-specific dimorphic effects. In conclusion, this paper describes the establishment of an animal model that shows sex differences in hyperoxic lung injury in a temporal manner and thus has important implications for lung diseases mediated by hyperoxia in humans. - Highlights: • Male mice were more susceptible to hyperoxic lung injury than females. • Sex differences in inflammatory markers were observed. • CYP1A expression was higher in females after hyperoxia exposure

  17. Sex-specific allelic transmission bias suggests sexual conflict at MC1R.

    Science.gov (United States)

    Ducret, Valérie; Gaigher, Arnaud; Simon, Céline; Goudet, Jérôme; Roulin, Alexandre

    2016-09-01

    Sexual conflict arises when selection in one sex causes the displacement of the other sex from its phenotypic optimum, leading to an inevitable tension within the genome - called intralocus sexual conflict. Although the autosomal melanocortin-1-receptor gene (MC1R) can generate colour variation in sexually dichromatic species, most previous studies have not considered the possibility that MC1R may be subject to sexual conflict. In the barn owl (Tyto alba), the allele MC1RWHITE is associated with whitish plumage coloration, typical of males, and the allele MC1RRUFOUS is associated with dark rufous coloration, typical of females, although each sex can express any phenotype. Because each colour variant is adapted to specific environmental conditions, the allele MC1RWHITE may be more strongly selected in males and the allele MC1RRUFOUS in females. We therefore investigated whether MC1R genotypes are in excess or deficit in male and female fledglings compared with the expected Hardy-Weinberg proportions. Our results show an overall deficit of 7.5% in the proportion of heterozygotes in males and of 12.9% in females. In males, interannual variation in assortative pairing with respect to MC1R explained the year-specific deviations from Hardy-Weinberg proportions, whereas in females, the deficit was better explained by the interannual variation in the probability of inheriting the MC1RWHITE or MC1RRUFOUS allele. Additionally, we observed that sons inherit the MC1RRUFOUS allele from their fathers on average slightly less often than expected under the first Mendelian law. Transmission ratio distortion may be adaptive in this sexually dichromatic species if males and females are, respectively, selected to display white and rufous plumages. © 2016 John Wiley & Sons Ltd.

  18. Analysis of case-parent trios for imprinting effect using a loglinear model with adjustment for sex-of-parent-specific transmission ratio distortion

    DEFF Research Database (Denmark)

    Huang, Lam Opal; Infante-Rivard, Claire; Labbe, Aurélie

    2017-01-01

    Transmission ratio distortion (TRD) is a phenomenon where parental transmission of disease allele to the child does not follow the Mendelian inheritance ratio. TRD occurs in a sex-of-parent-specific or non-sex-of-parent-specific manner. An offset computed from the transmission probability of the ...

  19. Bulked segregant analysis of the pirarucu (Arapaima gigas) genome for identification of sex-specific molecular markers.

    Science.gov (United States)

    Almeida, I G; Ianella, P; Faria, M T; Paiva, S R; Caetano, A R

    2013-12-04

    Arapaima gigas (Osteoglossidae) is one of the largest fish species in the Amazon Basin, attaining lengths of over 2.5 m and weights of over 100 kg. Its flesh is prized, and it has great potential for production in aquaculture systems. However, live pirarucu cannot be reliably sexed visually, even after sexual development, since this species does not have clear external sexual dimorphism. Simple and inexpensive methods for sexing immature pirarucu based on DNA markers would facilitate production of this species in commercial operations. We analyzed A. gigas male and female DNA pools with 566 RAPD primers, generating 2609 fragments, with an estimated 1341 segregating polymorphic markers, and an estimated average spacing of 714 kb, which corresponds to less than 0.1% of the species' genome. Two putative sex-specific fragments were initially identified in bulked samples; but they were not confirmed in a study of individual male and female samples. We suggest that A. gigas has developed a non-chromosomal system of sex determination or, alternatively, that the species has undergone a recent loss of the chromosome carrying the sex-determining locus.

  20. Fit-For-Purpose Land Administration

    DEFF Research Database (Denmark)

    Enemark, Stig; McLaren, Robin

    2017-01-01

    This paper looks at implementing Fit-For-Purpose land administration solutions at county level. This will require a country specific strategy drawing from the recent GLTN publication on “Fit-For-Purpose Land Administration – Guiding Principles for Country Implementation”. The Fit...... administration; 4) Designing the country specific FFP spatial / legal / institutional frameworks; 5) Capacity development; 6) Country specific instruction manuals; and 7) Economic benefits analysis. Finally, the paper presents some experiences and reflections from a case study on implementing the FFP approach...

  1. An R package for fitting age, period and cohort models

    Directory of Open Access Journals (Sweden)

    Adriano Decarli

    2014-11-01

    Full Text Available In this paper we present the R implementation of a GLIM macro which fits age-period-cohort model following Osmond and Gardner. In addition to the estimates of the corresponding model, owing to the programming capability of R as an object oriented language, methods for printing, plotting and summarizing the results are provided. Furthermore, the researcher has fully access to the output of the main function (apc which returns all the models fitted within the function. It is so possible to critically evaluate the goodness of fit of the resulting model.

  2. Identification of sex-specific urinary biomarkers for major depressive disorder by combined application of NMR- and GC-MS-based metabonomics.

    Science.gov (United States)

    Zheng, P; Chen, J-J; Zhou, C-J; Zeng, L; Li, K-W; Sun, L; Liu, M-L; Zhu, D; Liang, Z-H; Xie, P

    2016-11-15

    Women are more vulnerable to major depressive disorder (MDD) than men. However, molecular biomarkers of sex differences are limited. Here we combined gas chromatography-mass spectrometry (GC-MS)- and nuclear magnetic resonance (NMR)-based metabonomics to investigate sex differences of urinary metabolite markers in MDD, and further explore their potential of diagnosing MDD. Consequently, the metabolite signatures of women and men MDD subjects were significantly different from of that in their respective healthy controls (HCs). Twenty seven women and 36 men related differentially expressed metabolites were identified in MDD. Fourteen metabolites were changed in both women and men MDD subjects. Significantly, the women-specific (m-Hydroxyphenylacetate, malonate, glycolate, hypoxanthine, isobutyrate and azelaic acid) and men-specific (tyrosine, N-acetyl-d-glucosamine, N-methylnicotinamide, indoxyl sulfate, citrate and succinate) marker panels were further identified, which could differentiate men and women MDD patients from their respective HCs with higher accuracy than previously reported sex-nonspecific marker panels. Our findings demonstrate that men and women MDD patients have distinct metabonomic signatures and sex-specific biomarkers have promising values in diagnosing MDD.

  3. Sex-specific genetic determinants for arterial stiffness in Dahl salt-sensitive hypertensive rats.

    Science.gov (United States)

    Decano, Julius L; Pasion, Khristine A; Black, Nicole; Giordano, Nicholas J; Herrera, Victoria L; Ruiz-Opazo, Nelson

    2016-01-11

    Arterial stiffness is an independent predictor of cardiovascular outcomes in hypertensive patients including myocardial infarction, fatal stroke, cerebral micro-bleeds which predicts cerebral hemorrhage in hypertensive patients, as well as progression to hypertension in non-hypertensive subjects. The association between arterial stiffness and various cardiovascular outcomes (coronary heart disease, stroke) remains after adjusting for age, sex, blood pressure, body mass index and other known predictors of cardiovascular disease, suggesting that arterial stiffness, measured via carotid-femoral pulse wave velocity, has a better predictive value than each of these factors. Recent evidence shows that arterial stiffening precedes the onset of high blood pressure; however their molecular genetic relationship (s) and sex-specific determinants remain uncertain. We investigated whether distinct or shared genetic determinants might underlie susceptibility to arterial stiffening in male and female Dahl salt-sensitive rats. Thus, we performed a genome-wide scan for quantitative trait loci (QTLs) affecting arterial stiffness in six-week old F2 (Dahl S x R)-intercross male and female rats characterized for abdominal aortic pulse wave velocity and aortic strain by high-resolution ultrasonography. We detected five highly significant QTLs affecting aortic stiffness: two interacting QTLs (AS-m1 on chromosome 4 and AS-m2 on chromosome16, LOD 8.8) in males and two distinct interacting QTLs (AS-f1 on chromosome 9 and AS-f2 on chromosome11, LOD 8.9) in females affecting pulse wave velocity. One QTL (AS-1 on chromosome 3, LOD 4.3) was found to influence aortic strain in a sex-independent manner. None of these arterial stiffness QTLs co-localized with previously reported blood pressure QTLs detected in equivalent genetic intercrosses. These data reveal sex-specific genetic determinants for aortic pulse wave velocity and suggest distinct polygenic susceptibility for arterial stiffness and

  4. Let’s Talk About Same Sex: How Social Workers Can Make Judges Listen

    Directory of Open Access Journals (Sweden)

    Stephanie K. Boys

    2010-09-01

    Full Text Available Researchers have created a diverse toolbox of literature reporting that same sex cohabitating relationships are strikingly similar to heterosexual marriages in amicus curiae briefs submitted to the courts. However, judges are trained to fit information into legal frameworks and to ignore data that does not fit the rhetoric of a case. The following article aims to fit existing data on same sex relationships into the framework judges will use to decide whether same sex marriage can be prohibited. The primary precedent used to support same sex marriage is based on the analogy of a case prohibiting marriage discrimination based on race. The legal framework created by this case requires social work policy practitioners to frame research in terms of the evolution that has occurred in scientific understanding of same sex attraction and public opinion. A simple shift in the discourse used to frame the data can significantly impact whether judges listen.

  5. The evolution of female sex pheromones

    Directory of Open Access Journals (Sweden)

    Ally R. HARARI, Hadass STEINITZ

    2013-08-01

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

  6. Sex-specific factors for bone density in patients with schizophrenia.

    Science.gov (United States)

    Lin, Chieh-Hsin; Lin, Chun-Yuan; Huang, Tiao-Lai; Wang, Hong-Song; Chang, Yue-Cune; Lane, Hsien-Yuan

    2015-03-01

    Patients with schizophrenia are susceptible to low bone mineral density (BMD). Many risk factors have been suggested. However, it remains uncertain whether the risk factors differ between men and women. In addition, the study of bone density in men is neglected more often than that in women. This study aims to examine specific risk factors of low BMD in different sexes. Men (n=80) and women (n=115) with schizophrenia, similar in demographic and clinical characteristics, were enrolled in three centers. Clinical and laboratory variables (including blood levels of prolactin, sex and thyroid hormones, cortisol, calcium, and alkaline phosphatase) were collected. BMD was measured using a dual-energy X-ray absorptiometer. Men had lower BMD than women. Predictors for BMD in men included hyperprolactinemia (B=-0.821, P=0.009), body weight (B=0.024, P=0.046), and Global Assessment of Functioning score (B=0.027, P=0.043); in women, BMD was associated with menopause (B=-1.070, Pweight (B=0.027, P=0.003), and positive symptoms (B=0.094, Ploss in patients with schizophrenia. Physicians should pay particular attention to bone density in men with hyperprolactinemia and postmenopausal women. Further prospective studies in other populations are warranted to confirm these findings.

  7. Sex-Specific Patterns of Aberrant Brain Function in First-Episode Treatment-Naive Patients with Schizophrenia.

    Science.gov (United States)

    Lei, Wei; Li, Mingli; Deng, Wei; Zhou, Yi; Ma, Xiaohong; Wang, Qiang; Guo, Wanjun; Li, Yinfei; Jiang, Lijun; Han, Yuanyuan; Huang, Chaohua; Hu, Xun; Li, Tao

    2015-07-16

    Male and female patients with schizophrenia show significant differences in a number of important clinical features, yet the neural substrates of these differences are still poorly understood. Here we explored the sex differences in the brain functional aberrations in 124 treatment-naïve patients with first-episode schizophrenia (61 males), compared with 102 age-matched healthy controls (50 males). Maps of degree centrality (DC) and amplitude of low-frequency fluctuations (ALFF) were constructed using resting-state functional magnetic resonance imaging data and compared between groups. We found that: (1) Selective DC reduction was observed in the right putamen (Put_R) in male patients and the left middle frontal gyrus (MFG) in female patients; (2) Functional connectivity analysis (using Put_R and MFG as seeds) found that male and female patients have disturbed functional integration in two separate networks, i.e., the sensorimotor network and the default mode network; (3) Significant ALFF alterations were also observed in these two networks in both genders; (4) Sex specific brain functional alterations were associated with various symptoms in patients. These results suggested that sex-specific patterns of functional aberration existed in schizophrenia, and these patterns were associated with the clinical features both in male and female patients.

  8. Sex-specific responses to winter flooding, spring waterlogging and post-flooding recovery in Populus deltoides.

    Science.gov (United States)

    Miao, Ling-Feng; Yang, Fan; Han, Chun-Yu; Pu, Yu-Jin; Ding, Yang; Zhang, Li-Jia

    2017-05-31

    Winter flooding events are common in some rivers and streams due to dam constructions, and flooding and waterlogging inhibit the growth of trees in riparian zones. This study investigated sex-specific morphological, physiological and ultrastructural responses to various durations of winter flooding and spring waterlogging stresses, and post-flooding recovery characteristics in Populus deltoides. There were no significant differences in the morphological, ultrastructural and the majority of physiological traits in trees subjected to medium and severe winter flooding stresses, suggesting that males and females of P. deltoides were winter flooding tolerant, and insensitive to winter flooding duration. Males were more tolerant to winter flooding stress in terms of photosynthesis and chlorophyll fluorescence than females. Females displayed greater oxidative damage due to flooding stress than males. Males developed more efficient antioxidant enzymatic systems to control reactive oxygen species. Both sexes had similarly strong post-flooding recovery capabilities in terms of plant growth, and physiological and ultrastructural parameters. However, Males had better recovery capabilities in terms of pigment content. These results increase the understanding of poplars's adaptation to winter flooding stress. They also elucidate sex-specific differences in response to flooding stress during the dormant season, and during post-flooding recovery periods.

  9. Temporal and sex-specific variability in Rhinoceros Auklet diet in the central California Current system

    Science.gov (United States)

    Carle, Ryan D.; Beck, Jessie N.; Calleri, David M.; Hester, Michelle M.

    2015-06-01

    We used stable isotopes (δ15N and δ13C) and compared prey provided to chicks by each sex to evaluate seasonal and sex-specific diets in Rhinoceros Auklets (Cerorhinca monocerata) in the central California Current system during 2012-2013. Mixing models indicated northern anchovy (Engraulis mordax) were important prey for adults during fall/winter and juvenile rockfishes (Sebastes spp.) were important prey during incubation both years. Adult trophic level increased between incubation and chick-rearing periods in both years. During 2012, δ15N and δ13C of chick-rearing males and females differed significantly; mixing models indicated that females ate more Pacific saury (Cololabis saira) and less market squid (Doryteuthis opalescens) than males. Likewise, females delivered significantly more Pacific saury and less market squid to chicks than males during 2012. Chick growth (g d- 1) and chick survival to fledging were significantly lower during 2012 than 2013, likely because chicks were fed lesser quality prey or fed less frequently in 2012. Lesser body mass of females during incubation in 2012 indicated sex-specific diet differences may have been related to female energetic constraints. The observed variability in Rhinoceros Auklet diet underscores the importance of managing multiple prey populations in this system so that generalist predators have sufficient resources through changing conditions.

  10. Sex-Specific Patterns of Aberrant Brain Function in First-Episode Treatment-Naive Patients with Schizophrenia

    Directory of Open Access Journals (Sweden)

    Wei Lei

    2015-07-01

    Full Text Available Male and female patients with schizophrenia show significant differences in a number of important clinical features, yet the neural substrates of these differences are still poorly understood. Here we explored the sex differences in the brain functional aberrations in 124 treatment-naïve patients with first-episode schizophrenia (61 males, compared with 102 age-matched healthy controls (50 males. Maps of degree centrality (DC and amplitude of low-frequency fluctuations (ALFF were constructed using resting-state functional magnetic resonance imaging data and compared between groups. We found that: (1 Selective DC reduction was observed in the right putamen (Put_R in male patients and the left middle frontal gyrus (MFG in female patients; (2 Functional connectivity analysis (using Put_R and MFG as seeds found that male and female patients have disturbed functional integration in two separate networks, i.e., the sensorimotor network and the default mode network; (3 Significant ALFF alterations were also observed in these two networks in both genders; (4 Sex specific brain functional alterations were associated with various symptoms in patients. These results suggested that sex-specific patterns of functional aberration existed in schizophrenia, and these patterns were associated with the clinical features both in male and female patients.

  11. Associations of Sedentary Behavior, Physical Activity, Cardiorespiratory Fitness, and Body Fat Content With Pain Conditions in Children: The Physical Activity and Nutrition in Children Study.

    Science.gov (United States)

    Vierola, Anu; Suominen, Anna Liisa; Lindi, Virpi; Viitasalo, Anna; Ikävalko, Tiina; Lintu, Niina; Väistö, Juuso; Kellokoski, Jari; Närhi, Matti; Lakka, Timo A

    2016-07-01

    We investigated the cross-sectional associations of sedentary behavior, physical activity, cardiorespiratory fitness, and body fat content with pain conditions in prepubertal children. The participants were a population sample of 439 children aged 6 to 8 years. Sedentary behavior, physical activity, and pain conditions were assessed using questionnaires, cardiorespiratory fitness using maximal cycle ergometer test, and body fat percentage using dual-energy X-ray absorptiometry. The associations of sedentary behavior, physical activity, cardiorespiratory fitness, and body fat percentage with the risk of pain conditions were analyzed using multivariate logistic regression. Children in the highest sex-specific third of sedentary behavior had 1.95 (95% confidence interval [CI], 1.20-3.17; P = .007 for trend across thirds) times higher odds of any pain than children in the lowest third. Children in the highest sex-specific third of cardiorespiratory fitness had 46% (odds ratio [OR] = .54; 95% CI, .32-.91; P = .019) lower odds of any pain and 50% (OR = .50; 95% CI, .28-.87; P = .015) lower odds of headache than children in the lowest third. Children in the highest sex-specific third of body fat percentage had 44% (OR = .56; 95% CI, .34-.93; P = .023) lower odds of any pain, 49% (OR = .51; 95% CI, .30-.86; P = .011) lower risk of multiple pain, and 48% (OR = .52; 95% CI, .31-.86; P = .010) lower odds of lower limb pain than children in the lowest third. Physical activity was not associated with pain conditions. These findings suggest that prepubertal children with high levels of sedentary behavior, low levels of cardiorespiratory fitness, and low body fat content have increased likelihood of various pain conditions. This information could be used to develop strategies to prevent chronic pain in childhood. Our findings suggest that low cardiorespiratory fitness, high levels of sedentary behavior, and low body fat content are associated with increased

  12. High Rate of Return to High-Intensity Interval Training After Arthroscopic Management of Femoroacetabular Impingement Syndrome.

    Science.gov (United States)

    Riff, Andrew J; Ukwuani, Gift; Clapp, Ian; Movassaghi, Kamran; Kelly, D Michael; Nho, Shane J

    2018-06-01

    Since the inception of CrossFit in 2000, the popularity of high-intensity interval training (HIIT) in the United States has risen dramatically. While HIIT is a highly efficient exercise for weight loss and improved conditioning, some literature reports injuries in up to 34% of HIIT participants. We sought to evaluate the functional and sports-specific results of hip arthroscopic surgery in recreational HIIT participants. To evaluate patients' ability to return to HIIT after hip arthroscopic surgery for femoroacetabular impingement syndrome (FAIS). Case series; Level of evidence, 4. Consecutive patients with FAIS who had identified themselves as participating in HIIT and had undergone hip arthroscopic surgery for the treatment of FAIS by a single fellowship-trained surgeon between 2012 and 2015 were reviewed. Demographic data; preoperative physical examination findings; preoperative imaging results; preoperative patient-reported outcome (PRO) scores including the modified Harris Hip Score (mHHS), Hip Outcome Score-Activities of Daily Living (HOS-ADL), Hip Outcome Score-Sports-Specific Subscale (HOS-SSS), and visual analog scale (VAS) for pain; and postoperative examination and PRO scores at a minimum 2 years after surgery, including a HIIT-specific questionnaire, were assessed for all patients. Thirty-two patients (13 male, 19 female) with a mean age of 34.7 ± 6.9 years (range, 21-49 years) were identified with a minimum 24-month follow-up. Among these, 22 participated in CrossFit, 4 in Shred415, 3 in Orangetheory, and 3 in self-directed cross-training including plyometrics. Preoperatively, 14 patients had discontinued HIIT because of activity-related hip complaints, 17 patients had scaled back involvement in HIIT, and 1 patient maintained her baseline routine. Postoperatively, 28 of 32 patients (88%) returned to HIIT at a mean of 9.8 ± 5.7 months after surgery (range, 3-24 months); 96% returned to HIIT at the same level as or better than before the injury. Fear

  13. Integrative Analysis of Sex-Specific microRNA Networks Following Stress in Mouse Nucleus Accumbens.

    Science.gov (United States)

    Pfau, Madeline L; Purushothaman, Immanuel; Feng, Jian; Golden, Sam A; Aleyasin, Hossein; Lorsch, Zachary S; Cates, Hannah M; Flanigan, Meghan E; Menard, Caroline; Heshmati, Mitra; Wang, Zichen; Ma'ayan, Avi; Shen, Li; Hodes, Georgia E; Russo, Scott J

    2016-01-01

    Adult women are twice as likely as men to suffer from affective and anxiety disorders, although the mechanisms underlying heightened female stress susceptibility are incompletely understood. Recent findings in mouse Nucleus Accumbens (NAc) suggest a role for DNA methylation-driven sex differences in genome-wide transcriptional profiles. However, the role of another epigenetic process-microRNA (miR) regulation-has yet to be explored. We exposed male and female mice to Subchronic Variable Stress (SCVS), a stress paradigm that produces depression-like behavior in female, but not male, mice, and performed next generation mRNA and miR sequencing on NAc tissue. We applied a combination of differential expression, miR-mRNA network and functional enrichment analyses to characterize the transcriptional and post-transcriptional landscape of sex differences in NAc stress response. We find that male and female mice exhibit largely non-overlapping miR and mRNA profiles following SCVS. The two sexes also show enrichment of different molecular pathways and functions. Collectively, our results suggest that males and females mount fundamentally different transcriptional and post-transcriptional responses to SCVS and engage sex-specific molecular processes following stress. These findings have implications for the pathophysiology and treatment of stress-related disorders in women.

  14. Early sex differences are not autism-specific: A Baby Siblings Research Consortium (BSRC) study.

    Science.gov (United States)

    Messinger, Daniel S; Young, Gregory S; Webb, Sara Jane; Ozonoff, Sally; Bryson, Susan E; Carter, Alice; Carver, Leslie; Charman, Tony; Chawarska, Katarzyna; Curtin, Suzanne; Dobkins, Karen; Hertz-Picciotto, Irva; Hutman, Ted; Iverson, Jana M; Landa, Rebecca; Nelson, Charles A; Stone, Wendy L; Tager-Flusberg, Helen; Zwaigenbaum, Lonnie

    2015-01-01

    high-risk children with ASD, but also in high-risk children without ASD and in low-risk children. Sex differences in young children with ASD do not appear to be ASD-specific but instead reflect typically occurring sex differences seen in children without ASD. Results did not support a female protective effect hypothesis.

  15. Maturation of the human fetal startle response: evidence for sex-specific maturation of the human fetus.

    Science.gov (United States)

    Buss, Claudia; Davis, Elysia Poggi; Class, Quetzal A; Gierczak, Matt; Pattillo, Carol; Glynn, Laura M; Sandman, Curt A

    2009-10-01

    Despite the evidence for early fetal experience exerting programming influences on later neurological development and health risk, very few prospective studies of human fetal behavior have been reported. In a prospective longitudinal study, fetal nervous system maturation was serially assessed by monitoring fetal heart rate (FHR) responses to vibroacoustic stimulation (VAS) in 191 maternal/fetal dyads. Responses were not detected at 26 weeks gestational age (GA). Sex-specific, age-characteristic changes in the FHR response to VAS were observed by 31 weeks' GA. Males showed larger responses and continued to exhibit maturational changes until 37 weeks' GA, females however, presented with a mature FHR startle response by 31 weeks' GA. The results indicate that there are different rates of maturation in the male and female fetuses that may have implications for sex-specific programming influences.

  16. Functional specificity of sex pheromone receptors in the cotton bollworm Helicoverpa armigera.

    Directory of Open Access Journals (Sweden)

    Yang Liu

    Full Text Available Male moths can accurately perceive the sex pheromone emitted from conspecific females by their highly accurate and specific olfactory sensory system. Pheromone receptors are of special importance in moth pheromone reception because of their central role in chemosensory signal transduction processes that occur in olfactory receptor neurons in the male antennae. There are a number of pheromone receptor genes have been cloned, however, only a few have been functionally characterized. Here we cloned six full-length pheromone receptor genes from Helicoverpa armigera male antennae. Real-time PCR showing all genes exhibited male-biased expression in adult antennae. Functional analyses of the six pheromone receptor genes were then conducted in the heterologous expression system of Xenopus oocytes. HarmOR13 was found to be a specific receptor for the major sex pheromone component Z11-16:Ald. HarmOR6 was equally tuned to both of Z9-16: Ald and Z9-14: Ald. HarmOR16 was sensitively tuned to Z11-16: OH. HarmOR11, HarmOR14 and HarmOR15 failed to respond to the tested candidate pheromone compounds. Our experiments elucidated the functions of some pheromone receptor genes of H. armigera. These advances may provide remarkable evidence for intraspecific mating choice and speciation extension in moths at molecular level.

  17. Anthropometric measures as fitness indicators in primary school children: The Health Oriented Pedagogical Project (HOPP).

    Science.gov (United States)

    Mamen, Asgeir; Fredriksen, Per Morten

    2018-05-01

    As children's fitness continues to decline, frequent and systematic monitoring of fitness is important. Easy-to-use and low-cost methods with acceptable accuracy are essential in screening situations. This study aimed to investigate how the measurements of body mass index (BMI), waist circumference (WC) and waist-to-height ratio (WHtR) relate to selected measurements of fitness in children. A total of 1731 children from grades 1 to 6 were selected who had a complete set of height, body mass, running performance, handgrip strength and muscle mass measurements. A composite fitness score was established from the sum of sex- and age-specific z-scores for the variables running performance, handgrip strength and muscle mass. This fitness z-score was compared to z-scores and quartiles of BMI, WC and WHtR using analysis of variance, linear regression and receiver operator characteristic analysis. The regression analysis showed that z-scores for BMI, WC and WHtR all were linearly related to the composite fitness score, with WHtR having the highest R 2 at 0.80. The correct classification of fit and unfit was relatively high for all three measurements. WHtR had the best prediction of fitness of the three with an area under the curve of 0.92 ( p fit and unfit in this population.

  18. COHORT EFFECTS OF SUICIDE MORTALITY ARE SEX SPECIFIC IN THE RAPIDLY DEVELOPED HONG KONG CHINESE POPULATION, 1976-2010.

    Science.gov (United States)

    Chung, Roger Y; Yip, Benjamin H K; Chan, Sandra S M; Wong, Samuel Y S

    2016-06-01

    To examine temporal variations of age, period, and cohort on suicide mortality rate in Hong Kong (HK) from 1976 to 2010, and speculate the macroenvironmental mechanisms of the observed trends. Poisson age-period-cohort modeling was used to delineate the effects of age, period, and cohort on suicide mortality. Analysis by sex was also conducted to examine if gender difference exists for suicidal behaviours. Age-cohort model provides the best fit to the mortality data, implying that the cohort effect is likely to explain more of the contributions to HK's suicide mortality pattern than the period effect. Risk of suicide mortality increases nonlinearly with age and accelerates after age 65-69 for both sexes. Moreover, the cohort effects differ between the sexes-risk of mortality increases continually for men born after 1961, but no change is observed for women since the 1941 cohort. With increased risk of suicide mortality in younger cohorts and the age effect of suicide mortality, we may see future increase in suicide mortality as these younger cohorts age. Further studies are needed to clarify plausible associations between broader sociohistorical changes in the population impacting psychological risk factors and suicidal behaviour to better inform suicide prevention strategies. © 2015 Wiley Periodicals, Inc.

  19. Return to Golf After Lumbar Fusion.

    Science.gov (United States)

    Shifflett, Grant D; Hellman, Michael D; Louie, Philip K; Mikhail, Christopher; Park, Kevin U; Phillips, Frank M

    Spinal fusion surgery is being increasingly performed, yet few studies have focused on return to recreational sports after lumbar fusion and none have specifically analyzed return to golf. Most golfers successfully return to sport after lumbar fusion surgery. Case series. Level 4. All patients who underwent 1- or 2-level primary lumbar fusion surgery for degenerative pathologies performed by a single surgeon between January 2008 and October 2012 and had at least 1-year follow-up were included. Patients completed a specifically designed golf survey. Surveys were mailed, given during follow-up clinic, or answered during telephone contact. A total of 353 patients met the inclusion and exclusion criteria, with 200 responses (57%) to the questionnaire producing 34 golfers. The average age of golfers was 57 years (range, 32-79 years). In 79% of golfers, preoperative back and/or leg pain significantly affected their ability to play golf. Within 1 year from surgery, 65% of patients returned to practice and 52% returned to course play. Only 29% of patients stated that continued back/leg pain limited their play. Twenty-five patients (77%) were able to play the same amount of golf or more than before fusion surgery. Of those providing handicaps, 12 (80%) reported the same or an improved handicap. More than 50% of golfers return to on-course play within 1 year of lumbar fusion surgery. The majority of golfers can return to preoperative levels in terms of performance (handicap) and frequency of play. This investigation offers insight into when golfers return to sport after lumbar fusion surgery and provides surgeons with information to set realistic expectations postoperatively.

  20. Fitness-Specific Epistemic Beliefs, Effort Regulation, Outcomes, and Indices of Motivation in High School Physical Education

    Science.gov (United States)

    Lodewyk, Ken R.; Gao, Zan

    2013-01-01

    Epistemic beliefs are deeply held convictions about the nature of knowledge, knowing, and learning. In this study, approximately 500 ninth and tenth-grade physical education (PE) students completed fitness-specific measures assessing their epistemic beliefs in the simplicity and stability of knowledge and the speed of its acquisition along with…

  1. Goodness-of-fit tests with dependent observations

    International Nuclear Information System (INIS)

    Chicheportiche, Rémy; Bouchaud, Jean-Philippe

    2011-01-01

    We revisit the Kolmogorov–Smirnov and Cramér–von Mises goodness-of-fit (GoF) tests and propose a generalization to identically distributed, but dependent univariate random variables. We show that the dependence leads to a reduction of the 'effective' number of independent observations. The generalized GoF tests are not distribution-free but rather depend on all the lagged bivariate copulas. These objects, that we call 'self-copulas', encode all the non-linear temporal dependences. We introduce a specific, log-normal model for these self-copulas, for which a number of analytical results are derived. An application to financial time series is provided. As is well known, the dependence is to be long-ranged in this case, a finding that we confirm using self-copulas. As a consequence, the acceptance rates for GoF tests are substantially higher than if the returns were iid random variables

  2. Factors associated with prevalence and types of 'may be fit' advice on fit notes: a cross-sectional primary care analysis.

    Science.gov (United States)

    Shiels, Chris; Gabbay, Mark; Hillage, Jim

    2014-03-01

    The 'fit note', with the opportunity for the GP to advise that a patient 'may be fit' to do some work, was introduced in April 2010. To estimate numbers of fit notes with 'may be fit' advice, the types of advice, and factors associated with any inclusion of such advice in the fit note. Cross-sectional analysis of fit note data from 68 general practices in eight regions of England, Wales and Scotland. Collection of practice fit note data via GP use of carbonised pads of fit notes for a period of 12 months. The 'may be fit' box was ticked on 5080 fit notes (6.4% of all fit notes in study). But there was a wide variation in completion rates across the 68 practices (from 1% to 15%). The most prevalent individual item of advice was to 'amend duties' of patient as a prerequisite for return to work (included in 42% of all notes containing any 'may be fit' advice). Advice was often incomplete or irrelevant, with some GPs failing to comply with official guidance. Inclusion of any 'may be fit' advice was independently associated with the patient being female, less socially deprived and having a physical health reason for receiving a fit note. Unlike other studies that have relied upon eliciting opinion, this study investigates how the fit note is being used in practice. Findings provide some evidence that the fit note is not yet being used to the optimum benefit of patients (and their employers).

  3. Sex differences in the pathways to major depression: a study of opposite-sex twin pairs.

    Science.gov (United States)

    Kendler, Kenneth S; Gardner, Charles O

    2014-04-01

    The authors sought to clarify the nature of sex differences in the etiologic pathways to major depression. Retrospective and prospective assessments of 20 developmentally organized risk factors and the occurrence of past-year major depression were conducted at two waves of personal interviews at least 12 months apart in 1,057 opposite-sex dizygotic twin pairs from a population-based register. Analyses were conducted by structural modeling, examining within-pair differences. Sixty percent of all paths in the best-fit model exhibited sex differences. Eleven of the 20 risk factors differed across sexes in their impact on liability to major depression. Five had a greater impact in women: parental warmth, neuroticism, divorce, social support, and marital satisfaction. Six had a greater impact in men: childhood sexual abuse, conduct disorder, drug abuse, prior history of major depression, and distal and dependent proximal stressful life events. The life event categories responsible for the stronger effect in males were financial, occupational, and legal in nature. In a co-twin control design, which matches sisters and brothers on genetic and familial-environmental background, personality and failures in interpersonal relationships played a stronger etiologic role in major depression for women than for men. Externalizing psychopathology, prior depression, and specific "instrumental" classes of acute stressors were more important in the etiologic pathway to major depression for men. The results are consistent with previously proposed typologies of major depression that suggest two subtypes that differ in prevalence in women (deficiencies in caring relationships and interpersonal loss) and men (failures to achieve expected goals, with lowered self-worth).

  4. Cardiomyocyte-specific deletion of the G protein-coupled estrogen receptor (GPER) leads to left ventricular dysfunction and adverse remodeling: A sex-specific gene profiling analysis.

    Science.gov (United States)

    Wang, Hao; Sun, Xuming; Chou, Jeff; Lin, Marina; Ferrario, Carlos M; Zapata-Sudo, Gisele; Groban, Leanne

    2017-08-01

    Activation of G protein-coupled estrogen receptor (GPER) by its agonist, G1, protects the heart from stressors such as pressure-overload, ischemia, a high-salt diet, estrogen loss, and aging, in various male and female animal models. Due to nonspecific effects of G1, the exact functions of cardiac GPER cannot be concluded from studies using systemic G1 administration. Moreover, global knockdown of GPER affects glucose homeostasis, blood pressure, and many other cardiovascular-related systems, thereby confounding interpretation of its direct cardiac actions. We generated a cardiomyocyte-specific GPER knockout (KO) mouse model to specifically investigate the functions of GPER in cardiomyocytes. Compared to wild type mice, cardiomyocyte-specific GPER KO mice exhibited adverse alterations in cardiac structure and impaired systolic and diastolic function, as measured by echocardiography. Gene deletion effects on left ventricular dimensions were more profound in male KO mice compared to female KO mice. Analysis of DNA microarray data from isolated cardiomyocytes of wild type and KO mice revealed sex-based differences in gene expression profiles affecting multiple transcriptional networks. Gene Set Enrichment Analysis (GSEA) revealed that mitochondrial genes are enriched in GPER KO females, whereas inflammatory response genes are enriched in GPER KO males, compared to their wild type counterparts of the same sex. The cardiomyocyte-specific GPER KO mouse model provides us with a powerful tool to study the functions of GPER in cardiomyocytes. The gene expression profiles of the GPER KO mice provide foundational information for further study of the mechanisms underlying sex-specific cardioprotection by GPER. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Determinants for return to work among sickness certified patients in general practice

    Directory of Open Access Journals (Sweden)

    von Celsing Anna-Sophia

    2012-12-01

    Full Text Available Abstract Background Long-term sickness absence is one of the main risk factors for permanent exit out of the labour market. Early identification of the condition is essential to facilitate return to work. The aim of this study was to analyse possible determinants of return to work and their relative impact. Methods All 943 subjects aged 18 to 63 years, sickness certified at a Primary Health Care Centre in Sweden from 1 January until 31 August 2004, were followed up for three years. Baseline information on sex, age, sick leave diagnosis, employment status, extent of sick leave, and sickness absence during the year before baseline was obtained, as was information on all compensated days of sick leave, disability pension and death during follow-up. Results Slightly more than half the subjects were women, mean age was 39 years. Half of the study population returned to work within 14 days after baseline, and after three years only 15 subjects were still on sick leave. In multivariate proportional hazards regression analysis the extent of previous sick leave, age, being on part-time sick leave, and having a psychiatric, musculoskeletal, cardiovascular, nervous disease, digestive system, or injury or poisoning diagnosis decreased the return to work rate, while being employed increased it. Marital status, sex, being born in Sweden, citizenship, and annual salary had no influence. In logistic regression analyses across follow-up time these variables altogether explained 88-90% of return to work variation. Conclusions Return to work was positively or negatively associated by a number of variables easily accessible in the GP’s office. Track record data in the form of previous sick leave was the most influential variable.

  6. Gender profiling: a gendered race perspective on person-position fit.

    Science.gov (United States)

    Hall, Erika V; Galinsky, Adam D; Phillips, Katherine W

    2015-06-01

    The current research integrates perspectives on gendered race and person-position fit to introduce the concept of a gender profile. We propose that both the "gender" of a person's biological sex and the "gender" of a person's race (Asians are perceived as feminine and Blacks as masculine) help comprise an individual's gender profile-the overall femininity or masculinity associated with their demographic characteristics. We also propose that occupational positions have gender profiles. Finally, we argue that the overall gender profile of one's demographics, rather than just one's biological sex, determines one's fit and hirability for feminine or masculine occupational roles. The current five studies establish the gender profiles of different races and sexes, and then demonstrate that individuals with feminine-typed and masculine-typed gender profiles are selected for feminine and masculine positions, respectively. These studies provide new insights on who gets ahead in different environments. © 2015 by the Society for Personality and Social Psychology, Inc.

  7. The making of a modern female body: beauty, health and fitness in interwar Britain.

    Science.gov (United States)

    Zweiniger-Bargielowska, Ina

    2011-01-01

    In interwar Britain female athleticism, keep-fit classes and physical culture were celebrated as emblems of modernity, and women who cultivated their bodies in the pursuit of beauty, health and fitness represented civic virtue. This article argues that a modern, actively managed female body was part of women's liberation during this period. A modern female body required sex reform and birth control. Fitness culture was circumscribed by traditional notions of femininity. Women's competitive sport remained controversial and slimming in pursuit of fashion was widely condemned. Women from across the social spectrum embraced sport and joined fitness organizations. The rise of a modern female body contributed towards greater equality between the sexes. However, the gender order did not change fundamentally and the ideal woman of the interwar years was represented as a modern, emancipated race mother.

  8. Sickness certification for common mental disorders and GP return-to-work advice.

    Science.gov (United States)

    Gabbay, Mark; Shiels, Chris; Hillage, Jim

    2016-09-01

    Aim To report the types and duration of sickness certification for different common mental disorders (CMDs) and the prevalence of GP advice aimed at returning the patient to work. In the United Kingdom, common mental health problems, such and depression and stress, have become the main reasons for patients requesting a sickness certificate to abstain from usual employment. Increasing attention is being paid to mental health and its impact on employability and work capacity in all parts of the welfare system. However, relatively little is known about the extent to which different mental health diagnoses impact upon sickness certification outcomes, and how the GP has used the new fit note (introduced in 2010) to support a return to work for patients with mental health diagnoses. Sickness certification data was collected from 68 UK-based general practices for a period of 12 months. Findings The study found a large part of all sickness absence certified by GPs was due to CMDs (29% of all sickness absence episodes). Females, younger patients and those living in deprived areas were more likely to receive a fit note for a CMD (compared with one for a physical health problem). The highest proportion of CMD fit notes were issued for 'stress'. However, sickness certification for depression contributed nearly half of all weeks certified for mental health problems. Only 7% of CMD fit notes included any 'may be fit' advice from the GP, with type of advice varying by mental health diagnostic category. Patients living in the most socially deprived neighbourhoods were less likely to receive 'may be fit' advice on their CMD fit notes.

  9. Invariance in the recurrence of large returns and the validation of models of price dynamics

    Science.gov (United States)

    Chang, Lo-Bin; Geman, Stuart; Hsieh, Fushing; Hwang, Chii-Ruey

    2013-08-01

    Starting from a robust, nonparametric definition of large returns (“excursions”), we study the statistics of their occurrences, focusing on the recurrence process. The empirical waiting-time distribution between excursions is remarkably invariant to year, stock, and scale (return interval). This invariance is related to self-similarity of the marginal distributions of returns, but the excursion waiting-time distribution is a function of the entire return process and not just its univariate probabilities. Generalized autoregressive conditional heteroskedasticity (GARCH) models, market-time transformations based on volume or trades, and generalized (Lévy) random-walk models all fail to fit the statistical structure of excursions.

  10. Cytological studies of human meiosis: sex-specific differences in recombination originate at, or prior to, establishment of double-strand breaks.

    Directory of Open Access Journals (Sweden)

    Jennifer R Gruhn

    Full Text Available Meiotic recombination is sexually dimorphic in most mammalian species, including humans, but the basis for the male:female differences remains unclear. In the present study, we used cytological methodology to directly compare recombination levels between human males and females, and to examine possible sex-specific differences in upstream events of double-strand break (DSB formation and synaptic initiation. Specifically, we utilized the DNA mismatch repair protein MLH1 as a marker of recombination events, the RecA homologue RAD51 as a surrogate for DSBs, and the synaptonemal complex proteins SYCP3 and/or SYCP1 to examine synapsis between homologs. Consistent with linkage studies, genome-wide recombination levels were higher in females than in males, and the placement of exchanges varied between the sexes. Subsequent analyses of DSBs and synaptic initiation sites indicated similar male:female differences, providing strong evidence that sex-specific differences in recombination rates are established at or before the formation of meiotic DSBs. We then asked whether these differences might be linked to variation in the organization of the meiotic axis and/or axis-associated DNA and, indeed, we observed striking male:female differences in synaptonemal complex (SC length and DNA loop size. Taken together, our observations suggest that sex specific differences in recombination in humans may derive from chromatin differences established prior to the onset of the recombination pathway.

  11. Legal institutions, strategic default, and stock returns

    NARCIS (Netherlands)

    Favara, G.; Schroth, E.; Valta, P.

    2008-01-01

    This paper studies the impact of legal institutions on stock returns. More specifically, we examine how differences in debt enforcement and creditor protection around the world affect stock returns of individual firms. We hypothesize that if legal institutions prevent shareholders from engaging in

  12. Sex-specific kleptoparasitic foraging in ant-eating spiders

    DEFF Research Database (Denmark)

    Martisová, Martina; Bilde, T.; Pekar, Stano

    2009-01-01

    . To investigate this hypothesis, we studied the effect of sex and life history stage on the frequency of kleptoparasitism in ant-eating spiders of the genus Zodarion in the field. These spiders use a special capture technique involving a quick attack on an ant that is left unguarded by spiders for several minutes......, providing ample opportunities for kleptoparasitism. We found that adult females consistently hunted actively, while adult males ceased active prey capture and instead engaged in kleptoparasitism. Juvenile spiders were active hunters irrespective of sex. Consistent with an ontogenetic shift in foraging...

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

    Science.gov (United States)

    Fritzsche, Karoline; Arnqvis, Göran

    2013-07-01

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

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

    Directory of Open Access Journals (Sweden)

    Nayden Chakarov

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

  15. Gametogenesis in the Pacific oyster Crassostrea gigas: a microarrays-based analysis identifies sex and stage specific genes.

    Directory of Open Access Journals (Sweden)

    Nolwenn M Dheilly

    Full Text Available BACKGROUND: The Pacific oyster Crassostrea gigas (Mollusca, Lophotrochozoa is an alternative and irregular protandrous hermaphrodite: most individuals mature first as males and then change sex several times. Little is known about genetic and phenotypic basis of sex differentiation in oysters, and little more about the molecular pathways regulating reproduction. We have recently developed and validated a microarray containing 31,918 oligomers (Dheilly et al., 2011 representing the oyster transcriptome. The application of this microarray to the study of mollusk gametogenesis should provide a better understanding of the key factors involved in sex differentiation and the regulation of oyster reproduction. METHODOLOGY/PRINCIPAL FINDINGS: Gene expression was studied in gonads of oysters cultured over a yearly reproductive cycle. Principal component analysis and hierarchical clustering showed a significant divergence in gene expression patterns of males and females coinciding with the start of gonial mitosis. ANOVA analysis of the data revealed 2,482 genes differentially expressed during the course of males and/or females gametogenesis. The expression of 434 genes could be localized in either germ cells or somatic cells of the gonad by comparing the transcriptome of female gonads to the transcriptome of stripped oocytes and somatic tissues. Analysis of the annotated genes revealed conserved molecular mechanisms between mollusks and mammals: genes involved in chromatin condensation, DNA replication and repair, mitosis and meiosis regulation, transcription, translation and apoptosis were expressed in both male and female gonads. Most interestingly, early expressed male-specific genes included bindin and a dpy-30 homolog and female-specific genes included foxL2, nanos homolog 3, a pancreatic lipase related protein, cd63 and vitellogenin. Further functional analyses are now required in order to investigate their role in sex differentiation in oysters

  16. Multifactor analysis of multiscaling in volatility return intervals.

    Science.gov (United States)

    Wang, Fengzhong; Yamasaki, Kazuko; Havlin, Shlomo; Stanley, H Eugene

    2009-01-01

    We study the volatility time series of 1137 most traded stocks in the U.S. stock markets for the two-year period 2001-2002 and analyze their return intervals tau , which are time intervals between volatilities above a given threshold q . We explore the probability density function of tau , P_(q)(tau) , assuming a stretched exponential function, P_(q)(tau) approximately e;(-tau;(gamma)) . We find that the exponent gamma depends on the threshold in the range between q=1 and 6 standard deviations of the volatility. This finding supports the multiscaling nature of the return interval distribution. To better understand the multiscaling origin, we study how gamma depends on four essential factors, capitalization, risk, number of trades, and return. We show that gamma depends on the capitalization, risk, and return but almost does not depend on the number of trades. This suggests that gamma relates to the portfolio selection but not on the market activity. To further characterize the multiscaling of individual stocks, we fit the moments of tau , mu_(m) identical with(tautau);(m);(1m) , in the range of 10portfolio optimization.

  17. Multifactor analysis of multiscaling in volatility return intervals

    Science.gov (United States)

    Wang, Fengzhong; Yamasaki, Kazuko; Havlin, Shlomo; Stanley, H. Eugene

    2009-01-01

    We study the volatility time series of 1137 most traded stocks in the U.S. stock markets for the two-year period 2001-2002 and analyze their return intervals τ , which are time intervals between volatilities above a given threshold q . We explore the probability density function of τ , Pq(τ) , assuming a stretched exponential function, Pq(τ)˜e-τγ . We find that the exponent γ depends on the threshold in the range between q=1 and 6 standard deviations of the volatility. This finding supports the multiscaling nature of the return interval distribution. To better understand the multiscaling origin, we study how γ depends on four essential factors, capitalization, risk, number of trades, and return. We show that γ depends on the capitalization, risk, and return but almost does not depend on the number of trades. This suggests that γ relates to the portfolio selection but not on the market activity. To further characterize the multiscaling of individual stocks, we fit the moments of τ , μm≡⟨(τ/⟨τ⟩)m⟩1/m , in the range of 10portfolio optimization.

  18. "More Closeted Than Gayness Itself": The Depiction of Same-Sex Couple Violence in Newspaper Media.

    Science.gov (United States)

    Estes, Michelle L; Webber, Gretchen R

    2017-10-01

    Same-sex intimate partner violence (IPV) lacks mainstream news media coverage. News media report on those stories that are most prominent, and these stories are often shaped and presented within a White, heterosexual, upper-class, male framework. This framework largely ignores or misrepresents those that do not fit these characteristics, resulting in a gap in research and coverage of same-sex IPV. This article explores whether U.S. newspapers cover same-sex IPV, how often, and how same-sex couple violence is portrayed in newspapers when covered. Twenty-five newspaper articles published from 2005 to 2015, 10 years prior to the U.S. Supreme Court decision that legalized same-sex marriage, were located and analyzed. Findings indicate sparse newspaper coverage of IPV in same-sex couples. Ten articles highlight the lack of coverage and knowledge related to same-sex couple IPV. Eighteen articles address same-sex IPV as a social issue and highlight resource concerns, police involvement, and heteronormativity and heterosexism. Sixteen articles depict specific instances of IPV in same-sex couples. The overall lack of coverage and how same-sex IPV is covered remains problematic and limited. More mainstream and accurate coverage is needed to effectively address this social issue. Limitations and directions for future research are also discussed.

  19. Return to work and risk of subsequent detachment from employment after myocardial infarction

    DEFF Research Database (Denmark)

    Smedegaard, Laerke; Numé, Anna Karin; Charlot, Mette

    2017-01-01

    Background--Limited data are available on return to work and subsequent detachment from employment after admission for myocardial infarction (MI). Methods and Results--Using individual-level linkage of data from nationwide registries, we identified patients of working age (30-65 years) discharged...... after first-time MI in the period 1997 to 2012, who were employed before admission. To assess the cumulative incidence of return to work and detachment from employment, the Aalen Johansen estimator was used. Incidences were compared with population controls matched on age and sex. Logistic regression...... was applied to estimate odds ratios for associations between detachment from employment and age, sex, comorbidities, income, and education level. Of 39 296 patients of working age discharged after first-time MI, 22 394 (56.9%) were employed before admission. Within 1 year 91.1% (95% confidence interval [CI...

  20. The women's heart health programme: a pilot trial of sex-specific cardiovascular management.

    Science.gov (United States)

    Low, Ting Ting; Chan, Siew Pang; Wai, Shin Hnin; Ang, Zhou; Kyu, Kyu; Lee, Kim Yee; Ching, Anne; Comer, Sarah; Tan, Naomi Qiu Pin; Thong, Elizabeth Grace Hui En; Nang, Tracy; Dutta, Mohan; Lam, Carolyn S P

    2018-04-16

    There is increasing knowledge of sex-specific differences in cardiovascular disease and recognition of sex disparities in management. In our study, we investigated whether a cardiovascular programme tailored to the specific needs of women could lead to improved outcomes. We randomised 100 female patients to receive cardiology follow-up with the conventional sex-neutral cardiac programme (control), or the sex-tailored Women's Heart Health Programme (intervention). The intervention group was managed by an all-women multidisciplinary team and received culture-centred health intervention workshops, designed through in-depth interviews with the participants. The primary outcome was cardiovascular risk factor improvement at 1 year. Secondary outcomes include cardiovascular event rates, quality of life scores, and self-reported improvement in knowledge, attitudes, intentions and practices. Generalised structural equation model analysis was used to determine if the intervention group had better outcomes at alpha level 0.1. The mean age was 67.3 ± 12.7 years, with an ethnic distribution of 70% Chinese, 18% Malays, and 12% Indians. The majority of these patients had no formal or primary level of education (63%), and were mostly unemployed (78%). Patients in intervention group had better control of diabetes mellitus (lower HbA1c of 0.63% [CI 0.21-1.04], p = 0.015) and lower body-mass-index (0.74 kg/m 2 [CI 0.02-1.46], p = 0.092) at 1 year, but there was no significant difference in blood pressure or lipid control. Overall, there was a trend towards better risk factor control, 31.6% of intervention group versus 26.5% of control group achieved improvement in at least 1 CV risk factor control to target range. There was no significant difference in incidence of cardiovascular events, quality of life, or domains in knowledge, attitudes, intention and practices. This pilot study is the first of its kind evaluating a new model of care for women with heart disease

  1. Disentangling the complexities of vertebrate sex allocation : A role for squamate reptiles?

    NARCIS (Netherlands)

    Wapstra, Erik; Uller, Tobias; Pen, Ido; Komdeur, Jan; Olsson, Mats; Shine, Richard

    Sex allocation is an important field in evolutionary biology, both historically and currently. However, while sex allocation theory has successfully predicted sex ratio bias in some taxa, most notably parasitic wasps, vertebrates are notorious for their poor fit to theoretical models. We argue that

  2. Sex allocation predicts mating rate in a simultaneous hermaphrodite

    OpenAIRE

    Janicke, Tim; Schärer, Lukas

    2009-01-01

    Sexual selection theory for separate-sexed animals predicts that the sexes differ in the benefit they can obtain from multiple mating. Conventional sex roles assume that the relationship between the number of mates and the fitness of an individual is steeper in males compared with females. Under these conditions, males are expected to be more eager to mate, whereas females are expected to be choosier. Here we hypothesize that the sex allocation, i.e. the reproductive investment devoted to the...

  3. A new framework for estimating return levels using regional frequency analysis

    Science.gov (United States)

    Winter, Hugo; Bernardara, Pietro; Clegg, Georgina

    2017-04-01

    We propose a new framework for incorporating more spatial and temporal information into the estimation of extreme return levels. Currently, most studies use extreme value models applied to data from a single site; an approach which is inefficient statistically and leads to return level estimates that are less physically realistic. We aim to highlight the benefits that could be obtained by using methodology based upon regional frequency analysis as opposed to classic single site extreme value analysis. This motivates a shift in thinking, which permits the evaluation of local and regional effects and makes use of the wide variety of data that are now available on high temporal and spatial resolutions. The recent winter storms over the UK during the winters of 2013-14 and 2015-16, which have caused wide-ranging disruption and damaged important infrastructure, provide the main motivation for the current work. One of the most impactful natural hazards is flooding, which is often initiated by extreme precipitation. In this presentation, we focus on extreme rainfall, but shall discuss other meteorological variables alongside potentially damaging hazard combinations. To understand the risks posed by extreme precipitation, we need reliable statistical models which can be used to estimate quantities such as the T-year return level, i.e. the level which is expected to be exceeded once every T-years. Extreme value theory provides the main collection of statistical models that can be used to estimate the risks posed by extreme precipitation events. Broadly, at a single site, a statistical model is fitted to exceedances of a high threshold and the model is used to extrapolate to levels beyond the range of the observed data. However, when we have data at many sites over a spatial domain, fitting a separate model for each separate site makes little sense and it would be better if we could incorporate all this information to improve the reliability of return level estimates. Here

  4. Fetal sex-specific differences in gestational age at delivery in pre-eclampsia

    DEFF Research Database (Denmark)

    Schalekamp-Timmermans, Sarah; Arends, Lidia R.; Alsaker, Elin

    2017-01-01

    Background: Pre-eclampsia (PE) is a major pregnancy disorder complicating up to 8% of pregnancies. Increasing evidence indicates a sex-specific interplay between the mother,placenta and fetus. This may lead to different adaptive mechanisms during pregnancy. Methods: We performed an individual...... fetus as compared with pregnancies with a male fetus (OR 1.36, 95% CI 1.17-1.59). Conclusions: Sexual dimorphic differences in the occurrence of PE exist, with preterm PE being more prevalent among pregnancies with a female fetus as compared with pregnancies with a male fetus and with no differences...

  5. Spatial variability of maximum annual daily rain under different return periods at the Rio de Janeiro state, Brazil

    Directory of Open Access Journals (Sweden)

    Roriz Luciano Machado

    2010-01-01

    Full Text Available Knowledge of maximum daily rain and its return period in a region is an important tool to soil conservation, hydraulic engineering and preservation of road projects. The objective of this work was to evaluate the spatial variability of maximum annual daily rain considering different return periods, at the Rio de Janeiro State. The data set was composed by historical series of 119 rain gauges, for 36 years of observation. The return periods, estimated by Gumbel distribution, were 2, 5, 10, 25, 50 and 100 years. The spatial variability of the return periods was evaluated by semivariograms. All the return periods presented spatial dependence, with exponential and spherical model fitted to the experimental semivariograms. The parameters of the fitted semivariogram model were very similar; however, it was observed the presence of higher nugget effects for semivariograms of longer return periods. The values of maximum annual daily average rain in all the return periods increased from north to south and from countryside to the coast. In the region between the Serra do Mar range and the coast, besides increasing in magnitude, an increase in the spatial variability of the studied values with increasing return periods was also noticed. This behavior is probably caused by the orographic effect. The interpolated maps were more erratic for higher return periods and at the North, Northeast and Coastal Plain regions, in which the installation of new pluviometric stations are recommended.

  6. Household Composition and Longitudinal Health Outcomes for Older Mexican Return Migrants

    Science.gov (United States)

    Mudrazija, Stipica; López-Ortega, Mariana; Vega, William A.; Robledo, Luis Miguel Gutiérrez; Sribney, William

    2016-01-01

    Mexican return migrant population is increasing, yet our knowledge about their lives after resettlement in Mexico remains fragmentary. Using 2001–2012 longitudinal data from the Mexican Health and Aging Study, we investigate difference in household composition for older migrants who returned from the United States compared to nonmigrants. Furthermore, we fit a Cox proportional hazards model to assess the relationship between household composition and health and functional trajectories of return migrants and nonmigrants. The results indicate that return migrants with long duration of U.S. stay have different household composition than nonmigrants or short-term migrants: On average, they have smaller household size, including fewer females who may be available to offer assistance to older adults. Presence of middle-age females in the household has positive effects on health and functional trajectories. We highlight implications of this research for policy makers in Mexico and the United States. PMID:26966255

  7. Sex and caste-specific variation in compound eye morphology of five honeybee species.

    Directory of Open Access Journals (Sweden)

    Martin Streinzer

    Full Text Available Ranging from dwarfs to giants, the species of honeybees show remarkable differences in body size that have placed evolutionary constrains on the size of sensory organs and the brain. Colonies comprise three adult phenotypes, drones and two female castes, the reproductive queen and sterile workers. The phenotypes differ with respect to tasks and thus selection pressures which additionally constrain the shape of sensory systems. In a first step to explore the variability and interaction between species size-limitations and sex and caste-specific selection pressures in sensory and neural structures in honeybees, we compared eye size, ommatidia number and distribution of facet lens diameters in drones, queens and workers of five species (Apis andreniformis, A. florea, A. dorsata, A. mellifera, A. cerana. In these species, male and female eyes show a consistent sex-specific organization with respect to eye size and regional specialization of facet diameters. Drones possess distinctly enlarged eyes with large dorsal facets. Aside from these general patterns, we found signs of unique adaptations in eyes of A. florea and A. dorsata drones. In both species, drone eyes are disproportionately enlarged. In A. dorsata the increased eye size results from enlarged facets, a likely adaptation to crepuscular mating flights. In contrast, the relative enlargement of A. florea drone eyes results from an increase in ommatidia number, suggesting strong selection for high spatial resolution. Comparison of eye morphology and published mating flight times indicates a correlation between overall light sensitivity and species-specific mating flight times. The correlation suggests an important role of ambient light intensities in the regulation of species-specific mating flight times and the evolution of the visual system. Our study further deepens insights into visual adaptations within the genus Apis and opens up future perspectives for research to better understand the

  8. Aggregate Unemployment Decreases Individual Returns to Education

    Science.gov (United States)

    Ammermueller, Andreas; Kuckulenz, Anja; Zwick, Thomas

    2009-01-01

    Aggregate unemployment may affect individual returns to education through qualification-specific responses in participation and wage bargaining. This paper shows that an increase in regional unemployment by 1% decreases returns to education by 0.005 percentage points. This implies that higher skilled employees are better sheltered from labour…

  9. [Age- and sex-specific reference intervals for 10 health examination items: mega-data from a Japanese Health Service Association].

    Science.gov (United States)

    Suka, Machi; Yoshida, Katsumi; Kawai, Tadashi; Aoki, Yoshikazu; Yamane, Noriyuki; Yamauchi, Kuniaki

    2005-07-01

    To determine age- and sex-specific reference intervals for 10 health examination items in Japanese adults. Health examination data were accumulated from 24 different prefectural health service associations affiliated with the Japan Association of Health Service. Those who were non-smokers, drank less than 7 days/week, and had a body mass index of 18.5-24.9kg/m2 were sampled as a reference population (n = 737,538; 224,947 men and 512,591 women). After classified by age and sex, reference intervals for 10 health examination items (systolic blood pressure, diastolic blood pressure, total cholesterol, triglyceride, glucose, uric acid, AST, ALT, gamma-GT, and hemoglobin) were estimated using the parametric and nonparametric methods. In every item except for hemoglobin, men had higher reference intervals than women. Systolic blood pressure, total cholesterol, and glucose showed an upward trend in values with increasing age. Hemoglobin showed a downward trend in values with increasing age. Triglyceride, ALT, and gamma-GT reached a peak in middle age. Overall, parametric estimates showed narrower reference intervals than non-parametric estimates. Reference intervals vary with age and sex. Age- and sex-specific reference intervals may contribute to better assessment of health examination data.

  10. Mendelian randomization shows sex-specific associations between long-chain PUFA-related genotypes and cognitive performance in Danish schoolchildren

    DEFF Research Database (Denmark)

    Lauritzen, Lotte; Sorensen, Louise B.; Harslof, Laurine B.

    2017-01-01

    , and performance in the d2 Test of Attention and a reading test were analyzed in multiple regression models including all SNPs, SNP-sex interactions, and covariates related to testing conditions.Results:FADS, rs1535 minor allele carriage associated with lower whole-blood arachidonic acid (P ≤ 0.002), and minor...... alleles of rs174448 tended to associate with lower docosahexaenoic acid (DHA) (P = 0.052). We identified sex interactions in 50% of the SNP performance sets. Sex-dependent associations were observed for rs174448 and rs1535 on the d2 Test of Attention outcomes (P ... reading scores and rs174448 and rs2397142 (P sex-specific analyses showed associations in opposite directions in girls and boys. The minor allele carriage of rs174448 was associated with lower d2 Test of Attention performance (P

  11. Energetic fitness: Field metabolic rates assessed via 3D accelerometry complement conventional fitness metrics

    Science.gov (United States)

    Grémillet, David; Lescroël, Amelie; Ballard, Grant; Dugger, Katie M.; Massaro, Melanie; Porzig, Elizabeth L.; Ainley, David G.

    2018-01-01

    Evaluating the fitness of organisms is an essential step towards understanding their responses to environmental change. Connections between energy expenditure and fitness have been postulated for nearly a century. However, testing this premise among wild animals is constrained by difficulties in measuring energy expenditure while simultaneously monitoring conventional fitness metrics such as survival and reproductive output.We addressed this issue by exploring the functional links between field metabolic rate (FMR), body condition, sex, age and reproductive performance in a wild population.We deployed 3D accelerometers on 115 Adélie penguins Pygoscelis adeliae during four breeding seasons at one of the largest colonies of this species, Cape Crozier, on Ross Island, Antarctica. The demography of this population has been studied for the past 18 years. From accelerometry recordings, collected for birds of known age and breeding history, we determined the vector of the dynamic body acceleration (VeDBA) and used it as a proxy for FMR.This allowed us to demonstrate relationships among FMR, a breeding quality index (BQI) and body condition. Notably, we found a significant quadratic relationship between mean VeDBA during foraging and BQI for experienced breeders, and individuals in better body condition showed lower rates of energy expenditure.We conclude that using FMR as a fitness component complementary to more conventional fitness metrics will yield greater understanding of evolutionary and conservation physiology.

  12. Age and sex-specific relationships between phthalate exposures and obesity in Chinese children at puberty.

    Directory of Open Access Journals (Sweden)

    Yunhui Zhang

    Full Text Available To examine the age and sex-specific associations of urine levels of six mono-phthalates with body size and fat distribution in Chinese children at puberty.Four hundred and ninety-three school-aged children (247 boys, 246 girls were recruited. Obesity related anthropometric indices were measured and body fat proportion (BF% was calculated. Spot urine samples were collected and phthalate monoesters were detected by an API 2000 electrospray triple quadrupole mass spectrometer (ESI-MS/MS. Associations between phthalate exposure and overweight/obesity measures and their trends were examined by multiple linear regression and Logistic regression analyses, respectively.Di-2-ethylhexyl phthalate (DEHP metabolites and monobutyl phthalate (MBP were found to be the most detectable chemicals. In 8-10 years (yrs group, concentrations of MEHP and MBP were significantly higher in girls than those in boys. However, concentrations of all phthalate monoesters, except for MEP and MEHP, in 11-13 yrs boys were significantly higher than those in girls. After adjusting for confounders including puberty onset, urinary concentrations of MBP and sum of low molecular-weight phthalate metabolites (∑LMP were positively associated with boys' obesity in a concentration-effect manner, while concentrations of MEHP, MEHHP and sum of DEHP metabolites (∑MEHP were negatively associated with girls' obesity. Associations between phthalate exposure levels and BMI z-score changes were age- and sex-specific in school-age children.There are age and sex-specific concentration-effect associations between phthalate exposure and fat distribution in Chinese children. Urinary phthalate levels in 11-13 yrs boys were about 30 percent higher than those in girls, and ∑MEHP levels in younger boys (10 yrs. Associations were positive for MBP and ∑LMP with both BMI z-score and fat distribution in boys >10 years of age, and negative for ∑MEHP with fat distribution in girls <10 years of age.

  13. Annual variation in the levels of transcripts of sex-specific genes in the mantle of the common mussel, Mytilus edulis.

    Directory of Open Access Journals (Sweden)

    Sandhya Anantharaman

    Full Text Available Mytilus species are used as sentinels for the assessment of environmental health but sex or stage in the reproduction cycle is rarely considered even though both parameters are likely to influence responses to pollution. We have validated the use of a qPCR assay for sex identification and related the levels of transcripts to the reproductive cycle. A temporal study of mantle of Mytilus edulis found transcripts of male-specific vitelline coat lysin (VCL and female-specific vitelline envelope receptor for lysin (VERL could identify sex over a complete year. The levels of VCL/VERL were proportional to the numbers of sperm/ova and are indicative of the stage of the reproductive cycle. Maximal levels of VCL and VERL were found in February 2009 declining to minima between July - August before increasing and re-attaining a peak in February 2010. Water temperature may influence these transitions since they coincide with minimal water temperature in February and maximal temperature in August. An identical pattern of variation was found for a cryptic female-specific transcript (H5 but a very different pattern was observed for oestrogen receptor 2 (ER2. ER2 varied in a sex-specific way with male > female for most of the cycle, with a female maxima in July and a male maxima in December. Using artificially spawned animals, the transcripts for VCL, VERL and H5 were shown to be present in gametes and thus their disappearance from mantle is indicative of spawning. VCL and VERL are present at equivalent levels in February and July-August but during gametogenesis (August to January and spawning (March to June VCL is present at lower relative amounts than VERL. This may indicate sex-specific control mechanisms for these processes and highlight a potential pressure point leading to reduced reproductive output if environmental factors cause asynchrony to gamete maturation or release.

  14. Sex-Specific Effect of Recalled Parenting on Affective and Cognitive Empathy in Adulthood.

    Science.gov (United States)

    Lyons, Minna T; Brewer, Gayle; Bethell, Emily J

    2017-01-01

    Previous research has demonstrated the influence of parenting on the development of children's empathy. However, few studies have considered the impact of parents on empathy in adulthood, specific components of empathy, or the importance of parent and child biological sex. In the present study, 226 participants (71 men) completed online versions of the Parental Bonding Instrument (Parker et al. British Journal of Medical Psychology, 52, 1-10 1979), Empathy Quotient (Baron-Cohen and Wheelwright Journal of Autism and Developmental Disorders, 34, 163-175 2004), and Interpersonal Reactivity Index (Davis JSAS Catalog of Selected Documents in Psychology, 10, 85 1980). Paternal care and overprotection influenced affective empathy in men, whilst maternal overprotection predicted affective empathy in women. Further, maternal care related to cognitive empathy in men, whilst none of the parental care variables related to cognitive empathy in women. Findings are discussed in relation to sex differences in childhood parenting experiences on adult cognitive and affective empathy.

  15. Aerobic fitness after JDM--a long-term follow-up study

    DEFF Research Database (Denmark)

    Mathiesen, Pernille R; Orngreen, Mette C; Vissing, John

    2013-01-01

    Objectives. It has previously been shown that patients with active JDM have decreased aerobic fitness; however, it is not known whether these patients regain their physical fitness after recovery. The objective of this study was to investigate the long-term outcome of aerobic fitness in patients...... with JDM. We hypothesized that fitness (VO(2max)) is reduced compared with healthy controls in the years after active JDM.Methods. A maximal exercise test was performed using a cycle ergometer. Results were compared with those of sex- and age-matched healthy controls.Results. A total of 36 patients...... year of active disease, VO(2max) was reduced by 0.85 ml/min/kg on average (P fitness. This impairment is directly related to the duration of active disease....

  16. The impact of childhood abuse on inpatient substance users: specific links with risky sex, aggression, and emotion dysregulation.

    Science.gov (United States)

    Banducci, Anne N; Hoffman, Elana M; Lejuez, C W; Koenen, Karestan C

    2014-05-01

    Adults with substance use disorders (SUDs) report a high prevalence of childhood abuse. Research in the general population suggests specific types of abuse lead to particular negative outcomes; it is not known whether this pattern holds for adults with SUDs. We hypothesized that specific types of abuse would be associated with particular behavioral and emotional outcomes among substance users. That is, childhood sexual abuse would be associated with risky sex behaviors, childhood physical abuse with aggression, and childhood emotional abuse with emotion dysregulation. 280 inpatients (M age=43.3; 69.7% male; 88.4% African American) in substance use treatment completed the Childhood Trauma Questionnaire (CTQ), HIV Risk-Taking Behavior Scale, Addiction Severity Index, Difficulties with Emotion Regulation Scale (DERS), Distress Tolerance Scale (DTS), and Affect Intensity and Dimensions of Affiliation Motivation (AIM). Consistent with our hypotheses, the CTQ sexual abuse subscale uniquely predicted exchanging sex for cocaine and heroin, number of arrests for prostitution, engaging in unprotected sex with a casual partner during the prior year, and experiencing low sexual arousal when sober. The physical abuse subscale uniquely predicted number of arrests for assault and weapons offenses. The emotional abuse subscale uniquely predicted the DERS total score, AIM score, and DTS score. Among substance users, different types of abuse are uniquely associated with specific negative effects. Assessment of specific abuse types among substance users may be informative in treatment planning and relapse prevention. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Return to play in elite rugby union: application of global positioning system technology in return-to-running programs.

    Science.gov (United States)

    Reid, Laura C; Cowman, Jason R; Green, Brian S; Coughlan, Garrett F

    2013-05-01

    Global positioning systems (GPS) are widely used in sport settings to evaluate the physical demands on players in training and competition. The use of these systems in the design and implementation of rehabilitation and return-to-running programs has not yet been elucidated. To demonstrate the application of GPS technology in the management of return to play in elite-club Rugby Union. Case series. Professional Rugby Union club team. 8 elite Rugby Union players (age 27.86 ± 4.78 y, height 1.85 ± 0.08 m, weight 99.14 ± 9.96 kg). Players wore GPS devices for the entire duration of a club game. Variables of locomotion speed and distance were measured. Differences in physical demands between playing positions were observed for all variables. An analysis of the position-specific physical demands measured by GPS provides key information regarding the level and volume of loads sustained by a player in a game environment. Using this information, sports-medicine practitioners can develop rehabilitation and return-to-running protocols specific to the player position to optimize safe return to play.

  18. Sex-specific responses of Populus yunnanensis exposed to elevated CO{sub 2} and salinity

    Energy Technology Data Exchange (ETDEWEB)

    Ling Li; Yuanbin Zhang; Chunyang Li [Chinese Academy of Sciences. Chengdu Institute of Biology, Chengdu (Switzerland); Jianxun Luo, Sichuan Academy of Forestry, Chengdu (Switzerland)); Korpelainen, H. [Univ. of Helsinki. Dept. of Agricultural Sciences, Helsinki (Finland)

    2013-04-15

    Populus yunnanensis Dode., a native dioecious woody plant in southwestern China, was employed as a model species to study sex-specific morphological, physiological and biochemical responses to elevated CO{sub 2} and salinity. To investigate the effects of elevated CO{sub 2}, salinity and their combination, the cuttings were exposed to two CO{sub 2} regimes (ambient CO{sub 2} and double ambient CO{sub 2}) and two salt treatments in growth chambers. Males exhibited greater downregulation of net photosynthesis rate (A{sub net}) and carboxylation efficiency (CE) than females at elevated CO{sub 2}, whereas these sexual differences were lessened under salt stress. On the other hand, salinity induced a higher decrease in Anet and CE, more growth inhibition and leaf Cl{sup -} accumulation and more damage to cell organelles in females than in males, whereas the sexual differences in photosynthesis and growth were lessened at elevated CO{sub 2}. Moreover, elevated CO{sub 2} exacerbated membrane lipid peroxidation and organelle damage in females but not in males under salt stress. Our results indicated that: (1) females are more sensitive and suffer from greater negative effects than do males under salt stress, and elevated CO{sub 2} lessens the sexual differences in photosynthesis and growth under salt stress; (2) elevated CO{sub 2} tends to aggravate the negative effects of salinity in females; and (3) sex-specific reactions under the combination of elevated CO{sub 2} and salinity are distinct from single-stress responses. Therefore, these results provide evidence for different adaptive responses between plants of different sexes exposed to elevated CO{sub 2} and salinity. (Author)

  19. Genetic detection of sex-specific dispersal in historical and contemporary populations of anadromous brown trout Salmo trutta

    DEFF Research Database (Denmark)

    Bekkevold, Dorte; Hansen, Michael Møller; Mensberg, Karen-Lise Dons

    2004-01-01

    The study of sex-biased dispersal has attracted considerable attention in birds and mammals, but less in other taxa, including fishes. We analysed sex-specific dispersal in historical (1910s and 1950s) and contemporary (1990s) samples of anadromous brown trout Salmo trutta. We tested the hypothesis...... that dispersal is unbiased using information from microsatellite DNA and applying an assignment index for 11 temporally and spatially separated samples. Our results are most consistent with brown trout dispersal being male biased, and provide no evidence of female bias. We found no evidence that dispersal...

  20. Sex ratios

    OpenAIRE

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

    2002-01-01

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

  1. Low-carbohydrate, high-fat diets have sex-specific effects on bone health in rats

    DEFF Research Database (Denmark)

    Zengin, Ayse; Kropp, Benedikt; Chevalier, Yan

    2016-01-01

    the effects in female rats remain unknown. Therefore, we investigated whether sex-specific effects of LC-HF diets on bone health exist. METHODS: Twelve-week-old male and female Wistar rats were isoenergetically pair-fed either a control diet (CD), "Atkins-style" protein-matched diet (LC-HF-1), or ketogenic......PURPOSE: Studies in humans suggest that consumption of low-carbohydrate, high-fat diets (LC-HF) could be detrimental for growth and bone health. In young male rats, LC-HF diets negatively affect bone health by impairing the growth hormone/insulin-like growth factor axis (GH/IGF axis), while...... low-protein diet (LC-HF-2) for 4 weeks. In females, microcomputed tomography and histomorphometry analyses were performed on the distal femur. Sex hormones were analysed with liquid chromatography-tandem mass spectrometry, and endocrine parameters including GH and IGF-I were measured by immunoassay...

  2. Maturation of the human fetal startle response: Evidence for sex-specific maturation of the human fetus1

    Science.gov (United States)

    Buss, Claudia; Davis, Elysia Poggi; Class, Quetzal A.; Gierczak, Matt; Pattillo, Carol; Glynn, Laura M.; Sandman, Curt A.

    2009-01-01

    Despite the evidence for early fetal experience exerting programming influences on later neurological development and health risk, very few prospective studies of human fetal behavior have been reported. In a prospective longitudinal study, fetal nervous system maturation was serially assessed by monitoring fetal heart rate (FHR) responses to vibroacoustic stimulation (VAS) in 191 maternal/fetal dyads. Responses were not detected at 26 weeks gestational age (GA). Sex-specific, age-characteristic changes in the FHR response to VAS were observed by 31 weeks’ GA. Males showed larger responses and continued to exhibit maturational changes until 37 weeks’ GA, females however, presented with a mature FHR startle response by 31 weeks’ GA. The results indicate that there are different rates of maturation in the male and female fetus that may have implications for sex-specific programming influences. PMID:19726143

  3. Nucleotide variability at its limit? Insights into the number and evolutionary dynamics of the sex-determining specificities of the honey bee Apis mellifera.

    Science.gov (United States)

    Lechner, Sarah; Ferretti, Luca; Schöning, Caspar; Kinuthia, Wanja; Willemsen, David; Hasselmann, Martin

    2014-02-01

    Deciphering the evolutionary processes driving nucleotide variation in multiallelic genes is limited by the number of genetic systems in which such genes occur. The complementary sex determiner (csd) gene in the honey bee Apis mellifera is an informative example for studying allelic diversity and the underlying evolutionary forces in a well-described model of balancing selection. Acting as the primary signal of sex determination, diploid individuals heterozygous for csd develop into females, whereas csd homozygotes are diploid males that have zero fitness. Examining 77 of the functional heterozygous csd allele pairs, we established a combinatorical criteria that provide insights into the minimum number of amino acid differences among those pairs. Given a data set of 244 csd sequences, we show that the total number of csd alleles found in A. mellifera ranges from 53 (locally) to 87 (worldwide), which is much higher than was previously reported (20). Using a coupon-collector model, we extrapolate the presence of in total 116-145 csd alleles worldwide. The hypervariable region (HVR) is of particular importance in determining csd allele specificity, and we provide for this region evidence of high evolutionary rate for length differences exceeding those of microsatellites. The proportion of amino acids driven by positive selection and the rate of nonsynonymous substitutions in the HVR-flanking regions reach values close to 1 but differ with respect to the HVR length. Using a model of csd coalescence, we identified the high originating rate of csd specificities as a major evolutionary force, leading to an origin of a novel csd allele every 400,000 years. The csd polymorphism frequencies in natural populations indicate an excess of new mutations, whereas signs of ancestral transspecies polymorphism can still be detected. This study provides a comprehensive view of the enormous diversity and the evolutionary forces shaping a multiallelic gene.

  4. Nucleotide Variability at Its Limit? Insights into the Number and Evolutionary Dynamics of the Sex-Determining Specificities of the Honey Bee Apis mellifera

    Science.gov (United States)

    Lechner, Sarah; Ferretti, Luca; Schöning, Caspar; Kinuthia, Wanja; Willemsen, David; Hasselmann, Martin

    2014-01-01

    Deciphering the evolutionary processes driving nucleotide variation in multiallelic genes is limited by the number of genetic systems in which such genes occur. The complementary sex determiner (csd) gene in the honey bee Apis mellifera is an informative example for studying allelic diversity and the underlying evolutionary forces in a well-described model of balancing selection. Acting as the primary signal of sex determination, diploid individuals heterozygous for csd develop into females, whereas csd homozygotes are diploid males that have zero fitness. Examining 77 of the functional heterozygous csd allele pairs, we established a combinatorical criteria that provide insights into the minimum number of amino acid differences among those pairs. Given a data set of 244 csd sequences, we show that the total number of csd alleles found in A. mellifera ranges from 53 (locally) to 87 (worldwide), which is much higher than was previously reported (20). Using a coupon-collector model, we extrapolate the presence of in total 116–145 csd alleles worldwide. The hypervariable region (HVR) is of particular importance in determining csd allele specificity, and we provide for this region evidence of high evolutionary rate for length differences exceeding those of microsatellites. The proportion of amino acids driven by positive selection and the rate of nonsynonymous substitutions in the HVR-flanking regions reach values close to 1 but differ with respect to the HVR length. Using a model of csd coalescence, we identified the high originating rate of csd specificities as a major evolutionary force, leading to an origin of a novel csd allele every 400,000 years. The csd polymorphism frequencies in natural populations indicate an excess of new mutations, whereas signs of ancestral transspecies polymorphism can still be detected. This study provides a comprehensive view of the enormous diversity and the evolutionary forces shaping a multiallelic gene. PMID:24170493

  5. Sex specific effects of heat induced hormesis in Hsf-deficient Drosophila melanogaster

    DEFF Research Database (Denmark)

    Sørensen, J G; Kristensen, Torsten Nygård; Kristensen, K V

    2007-01-01

    In insects mild heat stress early in life has been reported to increase life span and heat resistance later in life, a phenomenon termed hormesis. Here, we test if the induction of the heat shock response by mild heat stress is mediating hormesis in longevity and heat resistance at older age...... line, seemingly mediated by the production of heat shock proteins (Hsps). The results indicate that heat inducible Hsps are important for heat induced hormesis in longevity and heat stress resistance. However, the results also suggest that other processes are involved and that different mechanisms...... might have marked sex specific impact...

  6. Sex hormone replacement in Turner syndrome

    DEFF Research Database (Denmark)

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

    2012-01-01

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

  7. The political economy of urban homicide: assessing the relative impact of gender inequality on sex-specific victimization.

    Science.gov (United States)

    DeWees, Mari A; Parker, Karen F

    2003-02-01

    This research examines the ways in which the changing political economy of urban areas has contributed differently to the homicide victimization rates of females and males across US cities. Recent research, while relatively limited, has presented disparate results regarding the effect of gender inequality on urban sex-specific victimization. Our work further explores this relationship by taking into account relative gender disparities in income, education, labor market opportunities, and politics in an examination of sex-specific homicide victimization in 1990. Key to this current investigation is the evaluation of feminist and lifestyle arguments that suggest that structural gender inequality has a unique effect on female victimization. Overall, our findings reveal gender inequality to be a significant predictor of both male and female urban homicide. While these findings suggest mixed support for theoretical arguments regarding gender inequality, further analyses reveal significant differences in specific types of gender inequality on victimization patterns across genders. These additional results highlight the need for greater attention toward both methodological and theoretical issues when examining the interconnections between gender, political economy, and violence in research.

  8. Physical Fitness and Serum Vitamin D and Cognition in Elderly Koreans

    Directory of Open Access Journals (Sweden)

    Jeong-Deok Ahn, Hyunsik Kang

    2015-12-01

    Full Text Available Poor physical fitness and low serum vitamin D are known to be modifiable risk factors for cognitive declines with normal aging. We investigated the association of physical fitness and serum vitamin D levels with global cognitive function in older adults. In this cross-sectional study, a total of 412 older Korean adults (108 men aged 74.4 ± 6.0 years and 304 women aged 73.1 ± 5.4 years completed the Korean version of Mini-Mental State Examination (MMSE to assess global cognitive performance and the senior fitness test to assess strength, flexibility, agility, and endurance domains of physical fitness. Body mass index, percent body fat, serum vitamin D, geriatric depression scale (GDS, level of education, smoking, and history of cardiovascular or cerebrovascular disease were also assessed as covariates. Age, sex, GDS, and body fatness were negatively associated with MMSE-based cognitive performance. Serum vitamin D and physical fitness were positively associated with MMSE-based cognitive performance. Multivariate linear regression showed that agility (partial R2 = -0.184, p = 0.029 and endurance (partial R2 = 0.191, p = 0.022 domains of physical fitness along with serum vitamin D (partial R2 = 0.210, p = 0.012 were significant predictors for global cognitive performance after controlling for covariates (i.e., age, sex, education, GDS, body fatness, and comorbidity index. The current findings of the study suggest that promotion of physical fitness and vitamin D supplementation should be key components of interventions to prevent cognitive decline with normal aging.

  9. Sex-specific ecophysiological responses to environmental fluctuations of free-ranging Hermann's tortoises: implication for conservation.

    Science.gov (United States)

    Sibeaux, Adélaïde; Michel, Catherine Louise; Bonnet, Xavier; Caron, Sébastien; Fournière, Kévin; Gagno, Stephane; Ballouard, Jean-Marie

    2016-01-01

    Physiological parameters provide indicators to evaluate how organisms respond to conservation actions. For example, individuals translocated during reinforcement programmes may not adapt to their novel host environment and may exhibit elevated chronic levels of stress hormones and/or decreasing body condition. Conversely, successful conservation actions should be associated with a lack of detrimental physiological perturbation. However, physiological references fluctuate over time and are influenced by various factors (e.g. sex, age, reproductive status). It is therefore necessary to determine the range of natural variations of the selected physiological metrics to establish useful baselines. This study focuses on endangered free-ranging Hermann's tortoises ( Testudo hermanni hermanni ), where conservation actions have been preconized to prevent extinction of French mainland populations. The influence of sex and of environmental factors (site, year and season) on eight physiological parameters (e.g. body condition, corticosterone concentrations) was assessed in 82 individuals from two populations living in different habitats. Daily displacements were monitored by radio-tracking. Most parameters varied between years and seasons and exhibited contrasting sex patterns but with no or limited effect of site. By combining behavioural and physiological traits, this study provides sex-specific seasonal baselines that can be used to monitor the health status of Hermann's tortoises facing environmental threats (e.g. habitat changes) or during conservation actions (e.g. translocation). These results might also assist in selection of the appropriate season for translocation.

  10. Sex-specific influences of mtDNA mitotype and diet on mitochondrial functions and physiological traits in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Wen C Aw

    Full Text Available Here we determine the sex-specific influence of mtDNA type (mitotype and diet on mitochondrial functions and physiology in two Drosophila melanogaster lines. In many species, males and females differ in aspects of their energy production. These sex-specific influences may be caused by differences in evolutionary history and physiological functions. We predicted the influence of mtDNA mutations should be stronger in males than females as a result of the organelle's maternal mode of inheritance in the majority of metazoans. In contrast, we predicted the influence of diet would be greater in females due to higher metabolic flexibility. We included four diets that differed in their protein: carbohydrate (P:C ratios as they are the two-major energy-yielding macronutrients in the fly diet. We assayed four mitochondrial function traits (Complex I oxidative phosphorylation, reactive oxygen species production, superoxide dismutase activity, and mtDNA copy number and four physiological traits (fecundity, longevity, lipid content, and starvation resistance. Traits were assayed at 11 d and 25 d of age. Consistent with predictions we observe that the mitotype influenced males more than females supporting the hypothesis of a sex-specific selective sieve in the mitochondrial genome caused by the maternal inheritance of mitochondria. Also, consistent with predictions, we found that the diet influenced females more than males.

  11. Piloting a Sex-Specific, Technology-Enhanced, Active Learning Intervention for Stroke Prevention in Women.

    Science.gov (United States)

    Dirickson, Amanda; Stutzman, Sonja E; Alberts, Mark J; Novakovic, Roberta L; Stowe, Ann M; Beal, Claudia C; Goldberg, Mark P; Olson, DaiWai M

    2017-12-01

    Recent studies reveal deficiencies in stroke awareness and knowledge of risk factors among women. Existing stroke education interventions may not address common and sex-specific risk factors in the population with the highest stroke-related rate of mortality. This pilot study assessed the efficacy of a technology-enhanced, sex-specific educational program ("SISTERS") for women's knowledge of stroke. This was an experimental pretest-posttest design. The sample consisted of 150 women (mean age, 55 years) with at least 1 stroke risk factor. Participants were randomized to either the intervention (n = 75) or control (n = 75) group. Data were collected at baseline and at a 2-week posttest. There was no statistically significant difference in mean knowledge score (P = .67), mean confidence score (P = .77), or mean accuracy score (P = .75) between the intervention and control groups at posttest. Regression analysis revealed that older age was associated with lower knowledge scores (P < .001) and lower confidence scores (P < .001). After controlling for age, the SISTERS program was associated with a statistically significant difference in knowledge (P < .001) and confidence (P < .001). Although no change occurred overall, after controlling for age, there was a statistically significant benefit. Older women may have less comfort with technology and require consideration for cognitive differences.

  12. Selection for narrow gate of emergence results in correlated sex-specific changes in life history of Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Vishwanath Varma

    2014-06-01

    Full Text Available Since the ability to time rhythmic behaviours in accordance with cyclic environments is likely to confer adaptive advantage to organisms, the underlying clocks are believed to be selected for stability in timekeeping over evolutionary time scales. Here we report the results of a study aimed at assessing fitness consequences of a long-term laboratory selection for tighter circadian organisation using fruit fly Drosophila melanogaster populations. We selected flies emerging in a narrow window of 1 h in the morning for several generations and assayed their life history traits such as pre-adult development time, survivorship, adult lifespan and lifetime fecundity. We chose flies emerging during the selection window (in the morning and another window (in the evening to represent adaptive and non-adaptive phenotypes, respectively, and examined the correlation of emergence time with adult fitness traits. Adult lifespan of males from the selected populations does not differ from the controls, whereas females from the selected populations have significantly shorter lifespan and produce more eggs during their mid-life compared to the controls. Although there is no difference in the lifespan of males of the selected populations, whether they emerge in morning or evening window, morning emerging females live slightly shorter and lay more eggs during the mid-life stage compared to those emerging in the evening. Interestingly, such a time of emergence dependent difference in fitness is not seen in flies from the control populations. These results, therefore, suggest reduced lifespan and enhanced mid-life reproductive output in females selected for narrow gate of emergence, and a sex-dependent genetic correlation between the timing of emergence and key fitness traits in these populations.

  13. Low muscle fitness is associated with metabolic risk in youth

    DEFF Research Database (Denmark)

    Steene-Johannessen, Jostein; Anderssen, Sigmund A; Kolle, Elin

    2009-01-01

    PURPOSE: To examine the independent associations of muscle fitness and cardiorespiratory fitness with clustered metabolic risk in youth. METHODS: In 2005-2006, a cohort of 9- and 15-yr-olds (N = 2818) was randomly selected from all regions of Norway. The participation rate was 89% and 74% among...... the 9-and 15-yr-olds, respectively. We assessed muscular strength by measuring explosive, isometric, and endurance strength. Cardiorespiratory fitness was measured directly as peak oxygen uptake during a cycle ergometry test. Risk factors included in the composite risk factor score (sum of z......-scores) were systolic blood pressure, triglyceride, high-density lipoprotein cholesterol, insulin resistance, and waist circumference. RESULTS: Muscle fitness was negatively associated with clustered metabolic risk, independent of cardiorespiratory fitness, and after adjustment for age, sex, and pubertal stage...

  14. Risk-Return Trade-Off for European Stock Markets

    DEFF Research Database (Denmark)

    Aslanidis, Nektarios; Christiansen, Charlotte; Savva, Christos S.

    This paper adopts dynamic factor models with macro-finance predictors to revisit the intertemporal risk-return relation in five large European stock markets. We identify country specific, Euro area, and global factors to determine the conditional moments of returns considering the role of higher...

  15. Sex-Specific Prediction Models for Sleep Apnea From the Hispanic Community Health Study/Study of Latinos.

    Science.gov (United States)

    Shah, Neomi; Hanna, David B; Teng, Yanping; Sotres-Alvarez, Daniela; Hall, Martica; Loredo, Jose S; Zee, Phyllis; Kim, Mimi; Yaggi, H Klar; Redline, Susan; Kaplan, Robert C

    2016-06-01

    We developed and validated the first-ever sleep apnea (SA) risk calculator in a large population-based cohort of Hispanic/Latino subjects. Cross-sectional data on adults from the Hispanic Community Health Study/Study of Latinos (2008-2011) were analyzed. Subjective and objective sleep measurements were obtained. Clinically significant SA was defined as an apnea-hypopnea index ≥ 15 events per hour. Using logistic regression, four prediction models were created: three sex-specific models (female-only, male-only, and a sex × covariate interaction model to allow differential predictor effects), and one overall model with sex included as a main effect only. Models underwent 10-fold cross-validation and were assessed by using the C statistic. SA and its predictive variables; a total of 17 variables were considered. A total of 12,158 participants had complete sleep data available; 7,363 (61%) were women. The population-weighted prevalence of SA (apnea-hypopnea index ≥ 15 events per hour) was 6.1% in female subjects and 13.5% in male subjects. Male-only (C statistic, 0.808) and female-only (C statistic, 0.836) prediction models had the same predictor variables (ie, age, BMI, self-reported snoring). The sex-interaction model (C statistic, 0.836) contained sex, age, age × sex, BMI, BMI × sex, and self-reported snoring. The final overall model (C statistic, 0.832) contained age, BMI, snoring, and sex. We developed two websites for our SA risk calculator: one in English (https://www.montefiore.org/sleepapneariskcalc.html) and another in Spanish (http://www.montefiore.org/sleepapneariskcalc-es.html). We created an internally validated, highly discriminating, well-calibrated, and parsimonious prediction model for SA. Contrary to the study hypothesis, the variables did not have different predictive magnitudes in male and female subjects. Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  16. The Individual Economic Returns to Volunteering in Work Life

    DEFF Research Database (Denmark)

    Qvist, Hans-Peter; Munk, Martin David

    2018-01-01

    This article examines the individual economic returns to volunteering during different stages of working life. The article uses a unique panel dataset created by combining rich survey data from Denmark with information on wages from administrative registers covering the period from 2004 to 2012....... Applying a two-way fixed effects regression model that controls for both period-specific and individual-specific effects, the article finds that for labour market entrants and for people in the early stages of their working life, an additional year of volunteer work experience yields a significant positive...... return. However, the economic returns to volunteer work experience decrease as a function of professional labour market experience. For people with more than six years of professional labour market experience, the economic returns to volunteer work experience are insignificant. On these grounds...

  17. Oceanic, Latitudinal, and Sex-Specific Variation in Demography of a Tropical Deepwater Snapper across the Indo-Pacific Region

    Directory of Open Access Journals (Sweden)

    Ashley J. Williams

    2017-12-01

    Full Text Available Deepwater tropical fisheries provide an important source of income and protein to Pacific and Indian Ocean coastal communities who are highly dependent on fish for food security. The development of quantitative assessments and management strategies for these deepwater fisheries has been hindered by insufficient biological and fisheries data. We examine the age-specific demography of the pygmy ruby snapper Etelis carbunculus, an important target species in tropical deepwater fisheries, across 90° of longitude and 20° of latitude in the Pacific and Indian Oceans. Our results show that growth of E. carbunculus varies significantly between oceans and sexes and across latitudes in both oceans. Estimates of natural and fishing mortality were similar between oceans, but higher for females than males in both oceans. Evidence of greater fishing pressure on females than males is likely due to the larger size-at-age of females compared to males, assuming that selectivity of the fishing gear is related directly to fish size. Sex ratios were significantly female biased in both oceans despite this species being gonochoristic, and maturity schedules were similar between sexes in the Pacific Ocean. This species exhibits a protracted spawning season from mid-spring to autumn (i.e., October to May in the Pacific Ocean. These results represent the first estimates of age-specific demographic parameters for E. carbunculus, and provide the foundation for the development of the first species-specific assessment models and harvest strategies for the species. Future stock assessment models for E. carbunculus should consider sex-specific demographic parameters and spatial variation in demography. Our results reveal substantial differences in biology between E. carbunculus and the giant ruby snapper E. sp., a cryptic congeneric species, and thus contribute to greater clarity in managing fisheries that are dependent on these two species. Furthermore, the improved

  18. Sex identification of four penguin species using locus-specific PCR.

    Science.gov (United States)

    Zhang, Peijun; Han, Jiabo; Liu, Quansheng; Zhang, Junxin; Zhang, Xianfeng

    2013-01-01

    Traditional methods for sex identification are not applicable to sexually monomorphic species, leading to difficulties in the management of their breeding programs. To identify sex in sexually monomorphic birds, molecular methods have been established. Two established primer pairs (2550F/2718R and p8/p2) amplify the CHD1 gene region from both the Z and W chromosomes. Here, we evaluated the use of these primers for sex identification in four sexually monomorphic penguin species: king penguins (Aptenodytes patagonicus), rockhopper penguins (Eudyptes chrysocome), gentoo penguins (Pygoscelis papua), and Magellanic penguins (Spheniscus magellanicus). For all species except rockhopper penguins, primer pair 2550F/2718R resulted in two distinct CHD1Z and CHD1W PCR bands, allowing for sex identification. For rockhopper penguins, only primer pair p8/p2 yielded different CHD1Z and CHD1W bands, which were faint and similar in size making them difficult to distinguish. As a result, we designed a new primer pair (PL/PR) that efficiently determined the gender of individuals from all four penguin species. Sequencing of the PCR products confirmed that they were from the CHD1 gene region. Primer pair PL/PR can be evaluated for use in sexing other penguin species, which will be crucial for the management of new penguin breeding programs. © 2012 Wiley Periodicals, Inc.

  19. The Returns to Education in Entrepreneurship

    DEFF Research Database (Denmark)

    Iversen, Jens; Malchow-Møller, Nikolaj; Sørensen, Anders

    2011-01-01

    The returns to education in self-employment are addressed in four different specifications of the relationship between log income and years of schooling. The specifications range from a standard Mincer equation with a constant percentage increase in income for an additional year of schooling...

  20. Sex-Specific Effects of Organophosphate Diazinon on the Gut Microbiome and Its Metabolic Functions.

    Science.gov (United States)

    Gao, Bei; Bian, Xiaoming; Mahbub, Ridwan; Lu, Kun

    2017-02-01

    There is growing recognition of the significance of the gut microbiome to human health, and the association between a perturbed gut microbiome with human diseases has been established. Previous studies also show the role of environmental toxicants in perturbing the gut microbiome and its metabolic functions. The wide agricultural use of diazinon, an organophosphate insecticide, has raised serious environmental health concerns since it is a potent neurotoxicant. With studies demonstrating the presence of a microbiome-gut-brain axis, it is possible that gut microbiome perturbation may also contribute to diazinon toxicity. We investigated the impact of diazinon exposure on the gut microbiome composition and its metabolic functions in C57BL/6 mice. We used a combination of 16S rRNA gene sequencing, metagenomics sequencing, and mass spectrometry-based metabolomics profiling in a mouse model to examine the functional impact of diazinon on the gut microbiome. 16S rRNA gene sequencing revealed that diazinon exposure significantly perturbed the gut microbiome, and metagenomic sequencing found that diazinon exposure altered the functional metagenome. Moreover, metabolomics profiling revealed an altered metabolic profile arising from exposure. Of particular significance, these changes were more pronounced for male mice than for female mice. Diazinon exposure perturbed the gut microbiome community structure, functional metagenome, and associated metabolic profiles in a sex-specific manner. These findings may provide novel insights regarding perturbations of the gut microbiome and its functions as a potential new mechanism contributing to diazinon neurotoxicity and, in particular, its sex-selective effects. Citation: Gao B, Bian X, Mahbub R, Lu K. 2017. Sex-specific effects of organophosphate diazinon on the gut microbiome and its metabolic functions. Environ Health Perspect 125:198-206; http://dx.doi.org/10.1289/EHP202.

  1. Risk-Return Trade-Off for European Stock Markets

    OpenAIRE

    Aslanidis, Nektarios; Christiansen, Charlotte; Savva, Christos S.

    2015-01-01

    This paper adopts dynamic factor models with macro-finance predictors to revisit the intertemporal risk-return relation in five large European stock markets. We identify country specific, Euro area, and global factors to determine the conditional moments of returns considering the role of higher-order moments as additional measures of risk. The preferred combination of factors varies across countries. In the linear model, there is a strong but negative relation between conditional returns and...

  2. Sex-specific differences in pathogen susceptibility in honey bees (Apis mellifera).

    Science.gov (United States)

    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.

  3. Sex-specific phenotypes of hyperthyroidism and hypothyroidism in mice

    OpenAIRE

    Rakov, Helena; Engels, Kathrin; H?nes, Georg Sebastian; Strucksberg, Karl-Heinz; Moeller, Lars Christian; K?hrle, Josef; Zwanziger, Denise; F?hrer, Dagmar

    2016-01-01

    Background Thyroid dysfunction is more common in the female population, however, the impact of sex on disease characteristics has rarely been addressed. Using a murine model, we asked whether sex has an influence on phenotypes, thyroid hormone status, and thyroid hormone tissue response in hyper- and hypothyroidism. Methods Hypo- and hyperthyroidism were induced in 5-month-old female and male wildtype C57BL/6N mice, by LoI/MMI/ClO4 ? or T4 i.p. treatment over 7?weeks, and control animals unde...

  4. In Nonobese Children, Fitness and BMI are Independent Predictors of Fasting Insulin.

    Science.gov (United States)

    Watson, Andrew M; Eickhoff, Jens; Nemeth, Blaise A; Carrel, Aaron L

    2015-05-01

    Although fitness and obesity have been shown to be independent predictors of cardiometabolic disease risk in obese children, this interaction is not well defined in nonobese children. The purpose of this study was to define the relationships between peak aerobic capacity, body composition, and fasting insulin levels in nonobese middle school children. 148 middle school children (mean age 11.0 ± 2.1 years, 49% male) underwent determination of body mass index (BMI) z-score, fasting glucose, fasting insulin, body composition by DXA scan (lean body mass and body fat percentage), and peak oxygen uptake per kg of lean body mass (VO2peak). Univariate correlations and multivariate regression analysis were used to identify independent predictors of fasting insulin using age, sex, percent body fat, body mass index z-score, and VO2peak. fasting insulin was significantly related to VO2peak (r =-0.37, p fasting insulin, while age (p = .39), sex (p = .49), and percent body fat (p = .72) did not. Among nonobese middle school children, fasting insulin is independently related to aerobic fitness after accounting for age, sex, and body composition. Public health efforts to reduce cardiometabolic disease risk among all adolescents should include exercise programs to increase cardiovascular fitness.

  5. The fetal programming effect of prenatal smoking on Igf1r and Igf1 methylation is organ- and sex-specific.

    Science.gov (United States)

    Meyer, Karolin F; Verkaik-Schakel, Rikst Nynke; Timens, Wim; Kobzik, Lester; Plösch, Torsten; Hylkema, Machteld N

    2017-01-01

    The impact of prenatal smoke exposure (PSE) on DNA methylation has been demonstrated in blood samples from children of smoking mothers, but evidence for sex-dependent smoke-induced effects is limited. As the identified differentially methylated genes can be associated with developmental processes, and insulin-like growth factors (IGFs) play a critical role in prenatal tissue growth, we hypothesized that PSE induces fetal programming of Igf1r and Igf1. Using a mouse model of smoking during pregnancy, we show that PSE alters promoter methylation of Igf1r and Igf1 and deregulates their gene expression in lung and liver of fetal (E17.5) and neonatal (D3) mouse offspring. By further comparing female versus male, lung versus liver, or fetal versus neonatal time point, our results demonstrate that CpG site-specific aberrant methylation patterns sex-dependently vary per organ and time point. Moreover, PSE reduces gene expression of Igf1r and Igf1, dependent on organ, sex, and offspring's age. Our results indicate that PSE may be a source of organ-specific rather than general systemic fetal programming. This is exemplified here by gene promoter methylation and mRNA levels of Igf1r and Igf1, together with a sex- and organ-specific naturally established correlation of both parameters that is affected by prenatal smoke exposure. Moreover, the comparison of fetuses with neonates suggests a CpG site-dependent reversibility/persistence of PSE-induced differential methylation patterns.

  6. Direct benefits of choosing a high-fitness mate can offset the indirect costs associated with intralocus sexual conflict.

    Science.gov (United States)

    Pischedda, Alison; Chippindale, Adam K

    2017-06-01

    Intralocus sexual conflict generates a cost to mate choice: high-fitness partners transmit genetic variation that confers lower fitness to offspring of the opposite sex. Our earlier work in the fruit fly, Drosophila melanogaster, revealed that these indirect genetic costs were sufficient to reverse potential "good genes" benefits of sexual selection. However, mate choice can also confer direct fitness benefits by inducing larger numbers of progeny. Here, we consider whether direct benefits through enhanced fertility could offset the costs associated with intralocus sexual conflict in D. melanogaster. Using hemiclonal analysis, we found that females mated to high-fitness males produced 11% more offspring compared to those mated to low-fitness males, and high-fitness females produced 34% more offspring than low-fitness females. These direct benefits more than offset the reduction in offspring fitness caused by intralocus sexual conflict, creating a net fitness benefit for each sex to pairing with a high-fitness partner. Our findings highlight the need to consider both direct and indirect effects when investigating the fitness impacts of mate choice. Direct fitness benefits may shelter sexually antagonistic alleles from selection, suggesting a novel mechanism for the maintenance of fitness variation. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  7. The effect of sex on the repeatability of evolution in different environments.

    Science.gov (United States)

    Lachapelle, Josianne; Colegrave, Nick

    2017-04-01

    The adaptive function of sex has been extensively studied, while less consideration has been given to the potential downstream consequences of sex on evolution. Here, we investigate one such potential consequence, the effect of sex on the repeatability of evolution. By affecting the repeatability of evolution, sex could have important implications for biodiversity, and for our ability to make predictions about the outcome of environmental change. We allowed asexual and sexual populations of Chlamydomonas reinhardtii to evolve in novel environments and monitored both their change in fitness and variance in fitness after evolution. Sex affected the repeatability of evolution by changing the importance of the effect of selection, chance, and ancestral constraints on the outcome of the evolutionary process. In particular, the effects of sex were highly dependent on the initial genetic composition of the population and on the environment. Given the lack of a consistent effect of sex on repeatability across the environments used here, further studies to dissect in more detail the underlying reasons for these differences as well as studies in additional environments are required if we are to have a general understanding of the effects of sex on the repeatability of evolution. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  8. ALFA: an automated line fitting algorithm

    Science.gov (United States)

    Wesson, R.

    2016-03-01

    I present the automated line fitting algorithm, ALFA, a new code which can fit emission line spectra of arbitrary wavelength coverage and resolution, fully automatically. In contrast to traditional emission line fitting methods which require the identification of spectral features suspected to be emission lines, ALFA instead uses a list of lines which are expected to be present to construct a synthetic spectrum. The parameters used to construct the synthetic spectrum are optimized by means of a genetic algorithm. Uncertainties are estimated using the noise structure of the residuals. An emission line spectrum containing several hundred lines can be fitted in a few seconds using a single processor of a typical contemporary desktop or laptop PC. I show that the results are in excellent agreement with those measured manually for a number of spectra. Where discrepancies exist, the manually measured fluxes are found to be less accurate than those returned by ALFA. Together with the code NEAT, ALFA provides a powerful way to rapidly extract physical information from observations, an increasingly vital function in the era of highly multiplexed spectroscopy. The two codes can deliver a reliable and comprehensive analysis of very large data sets in a few hours with little or no user interaction.

  9. Sex-specific responses of Populus deltoides to defoliation

    Directory of Open Access Journals (Sweden)

    Li Shuxin

    2017-12-01

    Full Text Available There has been an increasing interest in understanding the differential effects of sexual dimorphism on plant stress responses. However, there is no clear pattern in the responses of the sexes to defoliation. In this study, the effects of different severity of artificial defoliation on biomass production, total nonstructural carbohydrate (NSC concentration, and photosynthetic rate (PN of male and female Populus deltoides were examined. We used half and full defoliation to observe the differences between the sexes in three harvest dates (1 week, 4 weeks, and 8 weeks after treatments. We hypothesized that female and male P. deltoides compared with an undefoliated control would have compensatory growth in response to defoliation treatments. Results showed that half and full defoliation reduced the growth of both sexes. Following half defoliation, root growth was reduced, especially in males, at T2 (4 weeks after defoliation and T3 (8 weeks after defoliation, while males showed an increase in height increment under the half defoliation compared with the nondefoliation treatments. By contrast, females were more negatively affected by defoliation than males in terms of biomass after 8 weeks. One week after defoliation, PN increased significantly in females and males under half defoliation (+30%, +32%, respectively and full defoliation (+58%, +56%, respectively. However, 8 weeks after defoliation, there was little difference in PN between defoliated and undefoliated female cuttings. Increases in stomatal conductance (gs and leaf nitrogen were observed under fully defoliated female and male cuttings. Moreover, males had less NSC concentrations following half defoliation compared with females. Our results indicate that leaf compensatory growth in male cuttings of P. deltoides was maintained by obtaining greater photosynthetic capacity, higher leaf nitrogen, and lower NSC concentration following half and full defoliation. Our results highlight that

  10. Alfa-fetoprotein secreting ovarian sex cord-stromal tumor

    Directory of Open Access Journals (Sweden)

    Kusum D Jashnani

    2013-01-01

    Full Text Available Ovarian sex cord-stromal tumors are relatively infrequent neoplasms that account for approximately 8% of all primary ovarian tumors. They are a heterogeneous group of neoplasms composed of cells derived from gonadal sex cords (granulosa and Sertoli cells, specialized gonadal stroma (theca and Leydig cells, and fibroblasts. They may show androgenic or estrogenic manifestations. We report such a tumor associated with markedly raised serum alpha-fetoprotein (AFP levels in a young female presenting with a mass and defeminising symptoms. Serum AFP levels returned to normal on removal of tumor.

  11. An adaptive annual rhythm in the sex of first pigeon eggs

    NARCIS (Netherlands)

    Dijkstra, Cor; Riedstra, Bernd; Dekker, Arjan; Goerlich, Vivian C.; Daan, Serge; Groothuis, Ton G. G.

    When the reproductive value of male and female offspring varies differentially, parents are predicted to adjust the sex ratio of their offspring to maximize their fitness (Trivers and Willard, Science 179:90-92, 1973). Two factors have been repeatedly linked to skews in avian offspring sex ratio.

  12. Sex-related and non-sex-related comorbidity subtypes of tic disorders: a latent class approach.

    Science.gov (United States)

    Rodgers, S; Müller, M; Kawohl, W; Knöpfli, D; Rössler, W; Castelao, E; Preisig, M; Ajdacic-Gross, V

    2014-05-01

    Recent evidence suggests that there may be more than one Gilles de la Tourette syndrome (GTS)/tic disorder phenotype. However, little is known about the common patterns of these GTS/tic disorder-related comorbidities. In addition, sex-specific phenomenological data of GTS/tic disorder-affected adults are rare. Therefore, this community-based study used latent class analyses (LCA) to investigate sex-related and non-sex-related subtypes of GTS/tic disorders and their most common comorbidities. The data were drawn from the PsyCoLaus study (n = 3691), a population-based survey conducted in Lausanne, Switzerland. LCA were performed on the data of 80 subjects manifesting motor/vocal tics during their childhood/adolescence. Comorbid attention-deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder, depressive, phobia and panic symptoms/syndromes comprised the selected indicators. The resultant classes were characterized by psychosocial correlates. In LCA, four latent classes provided the best fit to the data. We identified two male-related classes. The first class exhibited both ADHD and depression. The second class comprised males with only depression. Class three was a female-related class depicting obsessive thoughts/compulsive acts, phobias and panic attacks. This class manifested high psychosocial impairment. Class four had a balanced sex proportion and comorbid symptoms/syndromes such as phobias and panic attacks. The complementary occurrence of comorbid obsessive thoughts/compulsive acts and ADHD impulsivity was remarkable. To the best of our knowledge, this is the first study applying LCA to community data of GTS symptoms/tic disorder-affected persons. Our findings support the utility of differentiating GTS/tic disorder subphenotypes on the basis of comorbid syndromes. © 2013 The Author(s) European Journal of Neurology © 2013 EFNS.

  13. Sex specific recruitment of a medial prefrontal cortex-hippocampal-thalamic system during context-dependent renewal of responding to food cues in rats.

    Science.gov (United States)

    Anderson, Lauren C; Petrovich, Gorica D

    2017-03-01

    Renewal, or reinstatement, of responding to food cues after extinction may explain the inability to resist palatable foods and change maladaptive eating habits. Previously, we found sex differences in context-dependent renewal of extinguished Pavlovian conditioned responding to food cues. Context-induced renewal involves cue-food conditioning and extinction in different contexts and the renewal of conditioned behavior is induced by return to the conditioning context (ABA renewal). Male rats showed renewal of responding while females did not. In the current study we sought to identify recruitment of key neural systems underlying context-mediated renewal and sex differences. We examined Fos induction within the ventromedial prefrontal cortex (vmPFC), hippocampal formation, thalamus and amygdala in male and female rats during the test for renewal. We found sex differences in vmPFC recruitment during renewal. Male rats in the experimental condition showed renewal of responding and had more Fos induction within the infralimbic and prelimbic vmPFC areas compared to controls that remained in the same context throughout training and testing. Females in the experimental condition did not show renewal or an increase in Fos induction. Additionally, Fos expression differed between experimental and control groups and between the sexes in the hippocampal formation, thalamus and amygdala. Within the ventral subiculum, the experimental groups of both sexes had more Fos compared to control groups. Within the dorsal CA1 and the anterior region of the paraventricular nucleus of the thalamus, in males, the experimental group had higher Fos induction, while both females groups had similar number of Fos-positive neurons. Within the capsular part of the central amygdalar nucleus, females in the experimental group had higher Fos induction, while males groups had similar amounts. The differential recruitment corresponded to the behavioral differences between males and females and suggests

  14. Risk and return in oilfield asset holdings

    International Nuclear Information System (INIS)

    Kretzschmar, Gavin L.; Kirchner, Axel; Reusch, Hans

    2008-01-01

    Convention suggests that emerging market investment should provide commensurately lower risk or higher returns than comparable assets in developed countries. This study demonstrates that emerging markets contain regulatory specificities that challenge asset valuation model convergence and potentially invert risk return convention. 292 oilfield assets are used to provide evidence that, under upward oil prices, emerging markets are characterized by progressive state participation in oilfield cash flows. Specifically, this work advances the low oil price paradigm of prior oil and gas asset valuation studies and provides evidence that emerging market state participation terms limit the corporate value of globalization for the sector. (author)

  15. Risk and return in oilfield asset holdings

    Energy Technology Data Exchange (ETDEWEB)

    Kretzschmar, Gavin L.; Kirchner, Axel; Reusch, Hans [University of Edinburgh, College of Humanities and Social Sciences, The Management School (United Kingdom)

    2008-11-15

    Convention suggests that emerging market investment should provide commensurately lower risk or higher returns than comparable assets in developed countries. This study demonstrates that emerging markets contain regulatory specificities that challenge asset valuation model convergence and potentially invert risk return convention. 292 oilfield assets are used to provide evidence that, under upward oil prices, emerging markets are characterized by progressive state participation in oilfield cash flows. Specifically, this work advances the low oil price paradigm of prior oil and gas asset valuation studies and provides evidence that emerging market state participation terms limit the corporate value of globalization for the sector. (author)

  16. Relationship among Fitness, Morphological Characteristics, Skills ...

    African Journals Online (AJOL)

    The specific morphological and fitness demands of the sport are, therefore, not fully understood. The purpose of this ... The findings convincingly suggest that coaches should include fitness, morphological and skills tests in their coaching and fitness programmes, team selection and talent identification processes. Keywords: ...

  17. Options for human ``return to the moon'' using tomorrow's SSTO, ISRU, and LOX-augmented NTR technologies

    Science.gov (United States)

    Borowski, Stanley K.

    1996-03-01

    The feasibility of conducting human missions to the Moon is examined assuming the use of three ``high leverage'' technologies: (1) a single-stage-to-orbit (SSTO) launch vehicle, (2) ``in-situ'' resource utilization (ISRU)—specifically ``lunar-derived'' liquid oxygen (LUNOX), and (3) LOX-augmented nuclear thermal rocket (LANTR) propulsion. Lunar transportation system elements consisting of a LANTR-powered lunar transfer vehicle (LTV) and a chemical propulsion lunar landing/Earth return vehicle (LERV) are configured to fit within the ``compact'' dimensions of the SSTO cargo bay (diameter: 4.6 m/length: 9.0 m) while satisfying an initial mass in low Earth orbit (IMLEO) limit of ˜60 t (3 SSTO launches). Using ˜8 t of LUNOX to ``reoxidize'' the LERV for a ``direct return'' flight to Earth reduces its size and mass allowing delivery to LEO on a single 20 t SSTO launch. Similarly, the LANTR engine's ability to operate at any oxygen/hydrogen mixture ratio from 0 to 7 with high specific impulse (˜940 to 515 s) is exploited to reduce hydrogen tank volume, thereby improving packaging of the LANTR LTV's ``propulsion'' and ``propellant modules''. Expendable and reusable, piloted and cargo missions and vehicle designs are presented along with estimates of LUNOX production required to support the different mission modes.

  18. physical fitness self-related by the elderly and its relationship

    African Journals Online (AJOL)

    CASA

    the majority of the elderly perceived their fitness as good or very good, with this variable being ... the benefits of physical activity (PA) and sport for the elderly, not only physically, but also psychologically ..... Relations of sex, age, perceived ...

  19. `Sex' - It's not only Women's Work: A Case for Refocusing on the Functional Role that Sex Plays in Work for both Women and Men.

    Science.gov (United States)

    Uretsky, Elanah

    2015-01-01

    Mention of the term sex work often invokes images of marginalized women at risk for HIV infection. Such images, however, are counterintuitive to the functional role intended by the movement that spawned use of the terms `sex work' and `sex worker'. This article looks at the sexual practices of men in urban China to argue for a return to a functional definition of `sex work', which was originally meant to legitimize the role sex plays in work. The progenitors of this movement intended to use `sex work' as a means to legitimize sex as an income generating activity for women involved in prostitution. I show that sex can also serve a functional role in the work-related duties of men seeking economic and political success in contemporary urban China. Men in China utilize sex as one way for demonstrating the loyalty necessary to access state-owned and controlled resources in a market economy governed under a Leninist system. Overall the article demonstrates that reclaiming perception of sex work as a functional rather than behavioral category can expand its use for preventing HIV among the broad subset of people who engage in sex as part of their work.

  20. Developmental and sex-specific differences in expression of neuropeptides derived from allatotropin gene in the silkmoth Bombyx mori.

    Science.gov (United States)

    Bednár, Branislav; Roller, Ladislav; Čižmár, Daniel; Mitrová, Diana; Žitňan, Dušan

    2017-05-01

    Allatotropin (AT) and related neuropeptides are widespread bioactive molecules that regulate development, food intake and muscle contractions in insects and other invertebrates. In moths, alternative splicing of the at gene generates three mRNA precursors encoding AT with different combinations of three structurally similar AT-like peptides (ATLI-III). We used in situ hybridization and immunohistochemistry to map the differential expression of these transcripts during the postembryonic development of Bombyx mori. Transcript encoding AT alone was expressed in numerous neurons of the central nervous system and frontal ganglion, whereas transcripts encoding AT with ATLs were produced by smaller specific subgroups of neurons in larval stages. Metamorphosis was associated with considerable developmental changes and sex-specific differences in the expression of all transcripts. The most notable was the appearance of AT/ATL transcripts (1) in the brain lateral neurosecretory cells producing prothoracicotropic hormone; (2) in the male-specific cluster of about 20 neurons in the posterior region of the terminal abdominal ganglion; (3) in the female-specific medial neurons in the abdominal ganglia AG2-7. Immunohistochemical staining showed that these neurons produced a mixture of various neuropeptides and innervated diverse peripheral organs. Our data suggest that AT/ATL neuropeptides are involved in multiple stage- and sex-specific functions during the development of B. mori.

  1. Physical fitness and psychological health in overweight/obese children: A cross-sectional study from the ActiveBrains project.

    Science.gov (United States)

    Rodriguez-Ayllon, M; Cadenas-Sanchez, C; Esteban-Cornejo, I; Migueles, J H; Mora-Gonzalez, J; Henriksson, P; Martín-Matillas, M; Mena-Molina, A; Molina-García, P; Estévez-López, F; Enriquez, G M; Perales, J C; Ruiz, J R; Catena, A; Ortega, F B

    2018-02-01

    To examine the associations of physical fitness (i.e. cardiorespiratory fitness, muscular strength, and speed/agility) with psychological distress and psychological well-being in overweight/obese pre-adolescent children. 110 overweight/obese children (10.0±1.1years old, 61 boys) from the ActiveBrains project (http://profith.ugr.es/activebrains) participated in this cross-sectional study. Physical fitness was evaluated by the ALPHA battery test. Cardiorespiratory fitness was additionally evaluated by a maximal incremental treadmill. Stress was assessed by the Children's Daily Stress Inventory, anxiety by the State-Trait Anxiety Inventory, depression by the Children Depression Inventory, positive affect and negative affect by the Positive and Negative Affect Scale for Children, happiness by the Subjective Happiness Scale, optimism by the Life Orientation Test, and self-esteem by the Rosenberg Self-Esteem questionnaire. Linear regression adjusted for sex and peak height velocity was used to examine associations. Absolute upper-body muscular strength was negatively associated with stress and negative affect (β=-0.246, p=0.047; β=-0.329, p=0.010, respectively). Furthermore, absolute lower-body muscular strength was negatively associated with negative affect (β=-0.301, p=0.029). Cardiorespiratory fitness, expressed by the last completed lap, and relative upper-body muscular strength were positively associated with optimism (β=0.220, p=0.042; β=0.240, p=0.017, respectively). Finally, absolute upper-body muscular strength was positively associated with self-esteem (β=0.362, p=0.003) independently of sex and weight status (p for interactions >0.3), and absolute lower-body muscular strength was also positively associated with self-esteem (β=0.352, p=0.008). Muscular strength was associated with psychological distress (i.e. stress and negative affect) and psychological well-being (i.e. optimism and self-esteem) as well as cardiorespiratory fitness was associated with

  2. A Stepwise Fitting Procedure for automated fitting of Ecopath with Ecosim models

    Directory of Open Access Journals (Sweden)

    Erin Scott

    2016-01-01

    Full Text Available The Stepwise Fitting Procedure automates testing of alternative hypotheses used for fitting Ecopath with Ecosim (EwE models to observation reference data (Mackinson et al. 2009. The calibration of EwE model predictions to observed data is important to evaluate any model that will be used for ecosystem based management. Thus far, the model fitting procedure in EwE has been carried out manually: a repetitive task involving setting >1000 specific individual searches to find the statistically ‘best fit’ model. The novel fitting procedure automates the manual procedure therefore producing accurate results and lets the modeller concentrate on investigating the ‘best fit’ model for ecological accuracy.

  3. Sexually antagonistic "zygotic drive" of the sex chromosomes.

    Directory of Open Access Journals (Sweden)

    William R Rice

    2008-12-01

    Full Text Available Genomic conflict is perplexing because it causes the fitness of a species to decline rather than improve. Many diverse forms of genomic conflict have been identified, but this extant tally may be incomplete. Here, we show that the unusual characteristics of the sex chromosomes can, in principle, lead to a previously unappreciated form of sexual genomic conflict. The phenomenon occurs because there is selection in the heterogametic sex for sex-linked mutations that harm the sex of offspring that does not carry them, whenever there is competition among siblings. This harmful phenotype can be expressed as an antagonistic green-beard effect that is mediated by epigenetic parental effects, parental investment, and/or interactions among siblings. We call this form of genomic conflict sexually antagonistic "zygotic drive", because it is functionally equivalent to meiotic drive, except that it operates during the zygotic and postzygotic stages of the life cycle rather than the meiotic and gametic stages. A combination of mathematical modeling and a survey of empirical studies is used to show that sexually antagonistic zygotic drive is feasible, likely to be widespread in nature, and that it can promote a genetic "arms race" between the homo- and heteromorphic sex chromosomes. This new category of genomic conflict has the potential to strongly influence other fundamental evolutionary processes, such as speciation and the degeneration of the Y and W sex chromosomes. It also fosters a new genetic hypothesis for the evolution of enigmatic fitness-reducing traits like the high frequency of spontaneous abortion, sterility, and homosexuality observed in humans.

  4. The Impact of Sex Work Interruption on Blood-Derived T Cells in Sex Workers from Nairobi, Kenya.

    Science.gov (United States)

    Omollo, Kenneth; Boily-Larouche, Geneviève; Lajoie, Julie; Kimani, Makobu; Cheruiyot, Julianna; Kimani, Joshua; Oyugi, Julius; Fowke, Keith Raymond

    Unprotected sexual intercourse exposes the female genital tract (FGT) to semen-derived antigens, which leads to a proinflammatory response. Studies have shown that this postcoital inflammatory response can lead to recruitment of activated T cells to the FGT, thereby increasing risk of HIV infection. The purpose of this study was to evaluate the impact of sex work on activation and memory phenotypes of peripheral T cells among female sex workers (FSW) from Nairobi, Kenya. Thirty FSW were recruited from the Pumwani Sex Workers Cohort, 10 in each of the following groups: HIV-exposed seronegative (at least 7 years in active sex work), HIV positive, and New Negative (HIV negative, less than 3 years in active sex work). Blood was obtained at three different phases (active sex work, abstinence from sex work-sex break, and following resumption of sex work). Peripheral blood mononuclear cells were isolated and stained for phenotypic markers (CD3, CD4, CD8, and CD161), memory phenotype markers (CD45RA and CCR7), activation markers (CD69, HLA-DR, and CD95), and the HIV coreceptor (CCR5). T-cell populations were compared between groups. In HIV-positive women, CD8+CCR5+ T cells declined at the sex break period, while CD4+CD161+ T cells increased when returning to sex work. All groups showed no significant changes in systemic T-cell activation markers following the interruption of sex work, however, significant reductions in naive CD8+ T cells were noted. For each of the study points, HIV positives had higher effector memory and CD8+CD95+ T cells and lower naive CD8+ T cells than the HIV-uninfected groups. Interruption of sex work had subtle effects on systemic T-cell memory phenotypes.

  5. Fetal sex determination in the first trimester of pregnancy using a Y chromosome-specific DNA probe

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Y.; Huang, S.; Chen, M.; Huang, Y.; Zhang, M.; Dong, J.; Ku, A.; Xu, S.

    1987-05-01

    Prenatal determination of fetal sex is important for the prevention of X-linked disorders such as hemophilia, Lesch-Nyhan syndrome and Duchenne muscular dystrophy. The complex procedures of prenatal diagnosis for X-linked disorders are unnecessary if the fetus is female, because usually no clinical symptoms ever appear in female. pY 3.4 probe used in this work for sex determination is a 3.4 kilobase human repeat sequence. The probe is specific for the Y chromosome of males and can be used for sex determination. The other prove pBLUR used in this paper as control is a widely dispersed, highly repeated human Alu family DNA sequence, represented equally in male and female DNA. On the basis of the relative densities of the autoradiographic spots produced by hybridization of fetal DNA with pY3.4 and pBLUR, the sex of fetus can be clearly identified. Further the authors can determine the radioactive intensity (cpm) of the hybridized DNA spots and the ratio of hybridization with Y3.4 to pBLUR (Y3.4/pBLUR x 10). Results show that the hybridization ratio of DNA from chorionic villi of male (1.03 +/- 0.24) is significantly higher than that of female (0.16 +/- 0.09). Therefore, sex determination of the fetus can be made, based on the ratio of pY3.4/pBLUR x 10. If necessary they can also use Southern hybridization with pY 3.4 probe of DNA isolated from chorionic villi to confirm the result of dot hybridization.

  6. Heavy Episodic Drinking and Alcohol-Related Consequences: Sex-Specific Differences in Parental Influences among Ninth-Grade Students

    Science.gov (United States)

    Doumas, Diana M.; Hausheer, Robin; Esp, Susan

    2015-01-01

    Parents impact adolescent substance abuse, but sex-specific influences are not well-understood. This study examined parental influences on adolescent drinking behavior in a sample of ninth-grade students (N = 473). Hierarchical regression analyses indicated parental monitoring, disapproval of teen alcohol use, and quality of parent-teen general…

  7. Sex-specific responses to winter flooding, spring waterlogging and post-flooding recovery in Populus deltoides

    OpenAIRE

    Ling-Feng Miao; Fan Yang; Chun-Yu Han; Yu-Jin Pu; Yang Ding; Li-Jia Zhang

    2017-01-01

    Winter flooding events are common in some rivers and streams due to dam constructions, and flooding and waterlogging inhibit the growth of trees in riparian zones. This study investigated sex-specific morphological, physiological and ultrastructural responses to various durations of winter flooding and spring waterlogging stresses, and post-flooding recovery characteristics in Populus deltoides. There were no significant differences in the morphological, ultrastructural and the majority of ph...

  8. Associations between self-estimated and measured physical fitness among 40-year-old men and women.

    Science.gov (United States)

    Mikkelsson, L; Kaprio, J; Kautiainen, H; Kujala, U M; Nupponen, H

    2005-10-01

    The aim was to evaluate whether 40-year-old men and women are able to estimate their level of fitness compared with actual measured physical fitness. Twenty-nine men and 35 women first completed a questionnaire at home and then their physical fitness was measured at laboratory. The index of self-estimated physical fitness was calculated by summing up the scores of self-estimated endurance, strength, speed and flexibility. The index of self-estimated endurance was calculated by summing up the scores of self-estimated endurance and those of the self-estimated distance they could run, cycle, ski and walk. The index of measured physical fitness was calculated by summing up the z-scores of a submaximal bicycle ergometer test, ergojump tests (counter-movement jump and jumping in 15 s), a 30-s sit-up test, hand-grip tests and a sit-and-reach test. The correlation (Spearman) between the indices of self-estimated and measured physical fitness was 0.54 for both sexes, and that between self-estimated endurance and measured endurance was 0.53 for both sexes. Maximal oxygen uptake estimated based on submaximal ergometer test was higher among those with longer self-estimated distance of running, cycling, skiing and walking (P for linear trend ski or walk. However, in some individuals self-estimation of fitness is not in agreement with the results of fitness tests.

  9. Explaining sex differences in lifespan in terms of optimal energy allocation in the baboon

    DEFF Research Database (Denmark)

    King, Annette M.; Kirkwood, Thomas B.L.; Shanley, Daryl P.

    2017-01-01

    and other physiological functions, to differ between males and females. We present a model in which females provide all offspring care and males compete for access to reproductive females and in which the partitioning of available energy between the competing fitness-enhancing functions of growth......We provide a quantitative test of the hypothesis that sex role specialization may account for sex differences in lifespan in baboons if such specialization causes the dependency of fitness upon longevity, and consequently the optimal resolution to an energetic trade-off between somatic maintenance...... from differences in the value of somatic maintenance relative to other fitness-enhancing functions in keeping with the disposable soma theory....

  10. Body mass index predicts selected physical fitness attributes but is not associated with performance on military relevant tasks in U.S. Army Soldiers.

    Science.gov (United States)

    Pierce, Joseph R; DeGroot, David W; Grier, Tyson L; Hauret, Keith G; Nindl, Bradley C; East, Whitfield B; McGurk, Michael S; Jones, Bruce H

    2017-11-01

    Army body composition standards are based upon validated criteria; however, certain field-expedient methodologies (e.g., weight-for-height, body mass index [BMI]) may disqualify individuals from service who may otherwise excel on physical performance and military-relevant tasks. The purpose was to assess soldier physical performance and military-specific task/fitness performance stratified by BMI. Cross-sectional observational study. Male (n=275) and female (n=46) soldiers performed a wide-array of physical fitness tests and military-specific tasks, including the Army physical fitness test (APFT). Within-sex performance data were analyzed by BMI tertile stratification or by Army Body Composition Program (ABCP) weight-for-height (calculated BMI) screening standards using ANOVA/Tukey post-hoc or independent t-tests, respectively. BMI stratification (higher vs. lower BMI) was associated with significant improvements in muscular strength and power, but also with decrements in speed/agility in male and female soldiers. Within the military specific tasks, a higher BMI was associated with an increased APFT 2-Mile Run time; however, performance on a 1600-m Loaded March or a Warrior Task and Battle Drill obstacle course was not related to BMI in either sex. Male and Female soldiers who did not meet ABCP screening standards demonstrated a slower 2-Mile Run time; however, not meeting the ABCP BMI standard only affected a minimal number (∼6%) of soldiers' ability to pass the APFT. Military body composition standards require a careful balance between physical performance, health, and military readiness. Allowances should be considered where tradeoffs exist between body composition classifications and performance on physical tasks with high military relevance. Published by Elsevier Ltd.

  11. Sex-specific variation in signaling pathways and gene expression patterns in human leukocytes in response to endotoxin and exercise.

    Science.gov (United States)

    Abbasi, Asghar; de Paula Vieira, Rodolfo; Bischof, Felix; Walter, Michael; Movassaghi, Masoud; Berchtold, Nicole C; Niess, Andreas M; Cotman, Carl W; Northoff, Hinnak

    2016-11-10

    While exercise effects on the immune system have received increasing attention in recent years, it remains unclear to what extent gender and fluctuations in sex hormones during menstrual cycle influence immunological responses to exercise. We investigated mRNA changes induced through exhaustive exercise (half-marathon; pre-exercise and post-exercise [30 min, 3 h, 24 h] on whole blood cultures ± lipopolysaccharide [LPS] [1 h]) with a specific focus on sex differences (men vs women in luteal phase) as an extension of our previous study. Inflammation related signaling pathways, TLRs, cytosolic DNA sensing and RIG-I like receptors were differentially activated between sexes in LPS-stimulated cultures. Genes differentially regulated between sexes included TNIP-1, TNIP-3, IL-6, HIVEP1, CXCL3, CCR3, IL-8, and CD69, revealing a bias towards less anti-inflammatory gene regulation in women compared to men. In addition, several genes relevant to brain function (KMO, DDIT4, VEGFA, IGF1R, IGF2R, and FGD4) showed differential activation between sexes. Some of these genes (e.g., KMO in women, DDIT4 in both sexes) potentially constitute neuroprotective mechanisms. These data reveal that the exercise-induced change in gene expression might be gender and menstrual cycle phase dependent.

  12. `Sex' – It's not only Women's Work: A Case for Refocusing on the Functional Role that Sex Plays in Work for both Women and Men

    Science.gov (United States)

    Uretsky, Elanah

    2014-01-01

    Mention of the term sex work often invokes images of marginalized women at risk for HIV infection. Such images, however, are counterintuitive to the functional role intended by the movement that spawned use of the terms `sex work' and `sex worker'. This article looks at the sexual practices of men in urban China to argue for a return to a functional definition of `sex work', which was originally meant to legitimize the role sex plays in work. The progenitors of this movement intended to use `sex work' as a means to legitimize sex as an income generating activity for women involved in prostitution. I show that sex can also serve a functional role in the work-related duties of men seeking economic and political success in contemporary urban China. Men in China utilize sex as one way for demonstrating the loyalty necessary to access state-owned and controlled resources in a market economy governed under a Leninist system. Overall the article demonstrates that reclaiming perception of sex work as a functional rather than behavioral category can expand its use for preventing HIV among the broad subset of people who engage in sex as part of their work. PMID:25642103

  13. The Role of Adiposity in the Association between Muscular Fitness and Cardiovascular Disease.

    Science.gov (United States)

    Pérez-Bey, Alejandro; Segura-Jiménez, Víctor; Fernández-Santos, Jorge Del Rosario; Esteban-Cornejo, Irene; Gómez-Martínez, Sonia; Veiga, Oscar L; Marcos, Ascensión; Castro-Piñero, José

    2018-05-11

    To test the associations of muscular fitness and body mass index (BMI), individually and combined, with clustered cardiovascular disease risk factors in children and adolescents and to analyze the mediator role of BMI in the association between muscular fitness and clustered cardiovascular disease risk factors. In total, 239 children (113 girls) and 270 adolescents (128 girls) participated in this cross-sectional study. Height and weight were assessed, and BMI was calculated. A cardiovascular disease risk factors index (CVDRF-I) was created from the combination of the following variables: waist circumference, systolic blood pressure, triglycerides, high-density lipoprotein cholesterol, and glucose. Handgrip strength/weight and standing long jump tests were used to assess muscular fitness. A muscular fitness index was computed from the combination of both tests. Muscular fitness index was associated with CVDRF-I in children of both sexes and adolescent boys; however, these associations disappeared after accounting for BMI. BMI was associated with CVDRF-I in both children and adolescents, even after adjusting for muscular fitness (all P < .001). In male and female children and in adolescent boys, the association between muscular fitness and CVDRF-I was mediated by BMI (all P < .001). Because there was no association between muscular fitness and CVDRF-I in adolescent girls, the mediation hypothesis was discarded. BMI is an independent predictor of CVDRF-I in children and adolescents of both sexes. Conversely, the effect of muscular fitness on CVDRF-I seems to be fully mediated by BMI levels in male and female children and in adolescent boys. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. Evaluation of sex specificity on oxidative stress induced in lungs of mice irradiated by 12C6+ ions

    International Nuclear Information System (INIS)

    Liu Yang; Zhang Hong; Zhang Luwei

    2008-01-01

    The aim of this work is to identify if there is sex specificity on 12 C 6+ ion-induced oxidative damage in mouse lung at different time points. Kun-Ming mice were divided into two groups, each composed of six males and six females: control group and irradiation group with a single acute dose of 4 Gy. Animals were sacrificed at 2, 4 and 12 h respectively, there lungs were removed immediately, and the oxidative stress-related biomarkers were measured by Diagnostic Reagent Kits. The results showed that the relative activities of superoxide dismutase (4 h), catalase (2 h) and Se-dependent glutathione peroxidase (12 h) have significant changes (P 12 C 6+ ion is pronounced in the lungs of males. We thought that these sex-responded differences may be attributed to the influence of sex hormones. (authors)

  15. Comparing the Impact of Specific Strength Training vs General Fitness Training on Professional Symphony Orchestra Musicians

    DEFF Research Database (Denmark)

    Nygaard Andersen, Lotte; Mann, Stephanie; Juul-Kristensen, Birgit

    2017-01-01

    Musculoskeletal symptoms, especially in the upper body, are frequent among professional symphony orchestra musicians. Physical exercise may relieve pain but might also interfere with playing performance. OBJECTIVE: To evaluate the feasibility and effect of "specific strength training" (SST) versus...... "general fitness training" (GFT). METHODS: A feasibility study using randomized controlled methods. Primarily, evaluations involved self-reported impact on instrument playing and satisfaction with the interventions. Secondary evaluations included pain intensity, hand-grip strength, aerobic capacity, body...

  16. Poorer right ventricular systolic function and exercise capacity in women after repair of tetralogy of fallot: a sex comparison of standard deviation scores based on sex-specific reference values in healthy control subjects.

    Science.gov (United States)

    Sarikouch, Samir; Boethig, Dietmar; Peters, Brigitte; Kropf, Siegfried; Dubowy, Karl-Otto; Lange, Peter; Kuehne, Titus; Haverich, Axel; Beerbaum, Philipp

    2013-11-01

    In repaired congenital heart disease, there is increasing evidence of sex differences in cardiac remodeling, but there is a lack of comparable data for specific congenital heart defects such as in repaired tetralogy of Fallot. In a prospective multicenter study, a cohort of 272 contemporary patients (158 men; mean age, 14.3±3.3 years [range, 8-20 years]) with repaired tetralogy of Fallot underwent cardiac magnetic resonance for ventricular function and metabolic exercise testing. All data were transformed to standard deviation scores according to the Lambda-Mu-Sigma method by relating individual values to their respective 50th percentile (standard deviation score, 0) in sex-specific healthy control subjects. No sex differences were observed in age at repair, type of repair conducted, or overall hemodynamic results. Relative to sex-specific controls, repaired tetralogy of Fallot in women had larger right ventricular end-systolic volumes (standard deviation scores: women, 4.35; men, 3.25; P=0.001), lower right ventricular ejection fraction (women, -2.83; men, -2.12; P=0.011), lower right ventricular muscle mass (women, 1.58; men 2.45; P=0.001), poorer peak oxygen uptake (women, -1.65; men, -1.14; Pstandard deviation scores in repaired tetralogy of Fallot suggest that women perform poorer than men in terms of right ventricular systolic function as tested by cardiac magnetic resonance and exercise capacity. This effect cannot be explained by selection bias. Further outcome data are required from longitudinal cohort studies.

  17. Distribution of sex steroid hormone receptors in the avian brain: functional implications for neural sex differences and sexual behaviors.

    NARCIS (Netherlands)

    Gahr, M.

    2001-01-01

    Developmental and seasonal changes in the production of androgens, estrogens, and progestins seem to control sex-specific differentiation and seasonal changes in appetitive and consummatory sexual behaviors of birds. This results in profound sex differences in the quality (sex-specific) or quantity

  18. The behavioural consequences of sex reversal in dragons

    Science.gov (United States)

    Li, Hong; Holleley, Clare E.; Elphick, Melanie; Georges, Arthur

    2016-01-01

    Sex differences in morphology, physiology, and behaviour are caused by sex-linked genes, as well as by circulating sex-steroid levels. Thus, a shift from genotypic to environmental sex determination may create an organism that exhibits a mixture of male-like and female-like traits. We studied a lizard species (Central Bearded Dragon, Pogona vitticeps), in which the high-temperature incubation of eggs transforms genetically male individuals into functional females. Although they are reproductively female, sex-reversed dragons (individuals with ZZ genotype reversed to female phenotype) resemble genetic males rather than females in morphology (relative tail length), general behaviour (boldness and activity level), and thermoregulatory tactics. Indeed, sex-reversed ‘females’ are more male-like in some behavioural traits than are genetic males. This novel phenotype may impose strong selection on the frequency of sex reversal within natural populations, facilitating rapid shifts in sex-determining systems. A single period of high incubation temperatures (generating thermally induced sex reversal) can produce functionally female individuals with male-like (or novel) traits that enhance individual fitness, allowing the new temperature-dependent sex-determining system to rapidly replace the previous genetically based one.

  19. BDNF deficiency and young-adult methamphetamine induce sex-specific effects on prepulse inhibition regulation

    Directory of Open Access Journals (Sweden)

    Elizabeth E Manning

    2013-06-01

    Full Text Available Brain-derived neurotrophic factor (BDNF has been implicated in the pathophysiology of schizophrenia, yet its role in the development of specific symptoms is unclear. Methamphetamine (METH users have an increased risk of psychosis and schizophrenia, and METH-treated animals have been used extensively as a model to study the positive symptoms of schizophrenia. We investigated whether METH treatment in BDNF heterozygous mutant mice (HET has cumulative effects on sensorimotor gating, including the disruptive effects of psychotropic drugs. BDNF HETs and WT littermates were treated during young-adulthood with METH and, following a two-week break, prepulse inhibition (PPI was examined. At baseline, BDNF HETs showed reduced PPI compared to WT mice irrespective of METH pre-treatment. An acute challenge with amphetamine (AMPH disrupted PPI but male BDNF HETs were more sensitive to this effect, irrespective of METH pre-treatment. In contrast, female mice treated with METH were less sensitive to the disruptive effects of AMPH, and there were no effects of BDNF genotype. Similar changes were not observed in the response to an acute apomorphine or MK-801 challenge. These results show that genetically-induced reduction of BDNF caused changes in a behavioural endophenotype relevant to the positive symptoms of schizophrenia. However, major sex differences were observed in the effects of a psychotropic drug challenge on this behaviour. These findings suggest sex differences in the effects of BDNF depletion and METH treatment on the monoamine signaling pathways that regulate PPI. Given that these same pathways are thought to contribute to the expression of positive symptoms in schizophrenia, this work suggests that there may be significant sex differences in the pathophysiology underlying these symptoms. Elucidating these sex differences may be important for our understanding of the neurobiology of schizophrenia and developing better treatments strategies for the

  20. Changes in physical fitness and sports participation among children with different levels of motor competence: a 2-year longitudinal study.

    Science.gov (United States)

    Fransen, Job; Deprez, Dieter; Pion, Johan; Tallir, Isabel B; D'Hondt, Eva; Vaeyens, Roel; Lenoir, Matthieu; Philippaerts, Renaat M

    2014-02-01

    The goal of this study was to investigate differences in physical fitness and sports participation over 2 years in children with relatively high, average, and low motor competence. Physical fitness and gross motor coordination of 501 children between 6-10 years were measured at baseline and baseline+2 years. The sample compromised 2 age cohorts: 6.00-7.99 and 8.00-9.99 years. An age and sex-specific motor quotient at baseline testing was used to subdivide these children into low (MQ competence groups. Measures of sports participation were obtained through a physical activity questionnaire in 278 of the same children. Repeated Measures MANCOVA and two separate ANOVAs were used to analyze differences in changes in physical fitness and measures of sports participation respectively. Children with high motor competence scored better on physical fitness tests and participated in sports more often. Since physical fitness levels between groups changed similarly over time, low motor competent children might be at risk for being less physically fit throughout their life. Furthermore, since low motor competent children participate less in sports, they have fewer opportunities of developing motor abilities and physical fitness and this may further prevent them from catching up with their peers with an average or high motor competence.

  1. COMPASS Final Report: Near Earth Asteroids Rendezvous and Sample Earth Returns (NEARER)

    Science.gov (United States)

    Oleson, Steven R.; McGuire, Melissa L.

    2009-01-01

    In this study, the Collaborative Modeling for Parametric Assessment of Space Systems (COMPASS) team completed a design for a multi-asteroid (Nereus and 1996 FG3) sample return capable spacecraft for the NASA In-Space Propulsion Office. The objective of the study was to support technology development and assess the relative benefits of different electric propulsion systems on asteroid sample return design. The design uses a single, heritage Orion solar array (SA) (approx.6.5 kW at 1 AU) to power a single NASA Evolutionary Xenon Thruster ((NEXT) a spare NEXT is carried) to propel a lander to two near Earth asteroids. After landing and gathering science samples, the Solar Electric Propulsion (SEP) vehicle spirals back to Earth where it drops off the first sample s return capsule and performs an Earth flyby to assist the craft in rendezvousing with a second asteroid, which is then sampled. The second sample is returned in a similar fashion. The vehicle, dubbed Near Earth Asteroids Rendezvous and Sample Earth Returns (NEARER), easily fits in an Atlas 401 launcher and its cost estimates put the mission in the New Frontier s (NF's) class mission.

  2. Local and neighboring patch conditions alter sex-specific movement in banana weevils.

    Science.gov (United States)

    Carval, Dominique; Perrin, Benjamin; Duyck, Pierre-François; Tixier, Philippe

    2015-12-01

    Understanding the mechanisms underlying the movements and spread of a species over time and space is a major concern of ecology. Here, we assessed the effects of an individual's sex and the density and sex ratio of conspecifics in the local and neighboring environment on the movement probability of the banana weevil, Cosmopolites sordidus. In a "two patches" experiment, we used radiofrequency identification tags to study the C. sordidus movement response to patch conditions. We showed that local and neighboring densities of conspecifics affect the movement rates of individuals but that the density-dependent effect can be either positive or negative depending on the relative densities of conspecifics in local and neighboring patches. We demonstrated that sex ratio also influences the movement of C. sordidus, that is, the weevil exhibits nonfixed sex-biased movement strategies. Sex-biased movement may be the consequence of intrasexual competition for resources (i.e., oviposition sites) in females and for mates in males. We also detected a high individual variability in the propensity to move. Finally, we discuss the role of demographic stochasticity, sex-biased movement, and individual heterogeneity in movement on the colonization process.

  3. Sex-specific effects of docosahexaenoic acid (DHA) on the microbiome and behavior of socially-isolated mice.

    Science.gov (United States)

    Davis, Daniel J; Hecht, Patrick M; Jasarevic, Eldin; Beversdorf, David Q; Will, Matthew J; Fritsche, Kevin; Gillespie, Catherine H

    2017-01-01

    Dietary supplementation with the long-chain omega-3 polyunsaturated fatty acid docosahexaenoic acid (DHA) has been shown to have a beneficial effect on reducing the symptoms associated with several neuropsychiatric conditions including anxiety and depression. However, the mechanisms underlying this effect remain largely unknown. Increasing evidence suggests that the vast repertoire of commensal bacteria within the gut plays a critical role in regulating various biological processes in the brain and may contribute to neuropsychiatric disease risk. The present study determined the contribution of DHA on anxiety and depressive-like behaviors through modulation of the gut microbiota in a paradigm of social isolation. Adult male and female mice were subjected to social isolation for 28days and then placed either on a control diet or a diet supplemented with 0.1% or 1.0% DHA. Fecal pellets were collected both 24h and 7days following the introduction of the new diets. Behavioral testing revealed that male mice fed a DHA diet, regardless of dose, exhibited reduced anxiety and depressive-like behaviors compared to control fed mice while no differences were observed in female mice. As the microbiota-brain-axis has been recently implicated in behavior, composition of microbial communities were analyzed to examine if these sex-specific effects of DHA may be associated with changes in the gut microbiota (GM). Clear sex differences were observed with males and females showing distinct microbial compositions prior to DHA supplementation. The introduction of DHA into the diet also induced sex-specific interactions on the GM with the fatty acid producing a significant effect on the microbial profiles in males but not in females. Interestingly, levels of Allobaculum and Ruminococcus were found to significantly correlate with the behavioral changes observed in the male mice. Predictive metagenome analysis using PICRUSt was performed on the fecal samples collected from males and

  4. Genotype-specific interactions and the trade-off between host and parasite fitness

    Directory of Open Access Journals (Sweden)

    Shykoff Jacqui A

    2007-10-01

    Full Text Available Abstract Background Evolution of parasite traits is inextricably linked to their hosts. For instance one common definition of parasite virulence is the reduction in host fitness due to infection. Thus, traits of infection must be viewed in both protagonists and may be under shared genetic and physiological control. We investigated these questions on the oomycete Hyaloperonospora arabidopsis (= parasitica, a natural pathogen of the Brassicaceae Arabidopsis thaliana. Results We performed a controlled cross inoculation experiment confronting six lines of the host plant with seven strains of the parasite in order to evaluate genetic variation for phenotypic traits of infection among hosts, parasites, and distinct combinations. Parasite infection intensity and transmission were highly variable among parasite strains and host lines but depended also on the interaction between particular genotypes of the protagonists, and genetic variation for the infection phenotype of parasites from natural populations was found even at a small spatial scale within population. Furthermore, increased parasite fitness led to a significant decrease in host fitness only on a single host line (Gb, although a trade-off between these two traits was expected because host and parasite share the same resource pool for their respective reproduction. We propose that different levels of compatibility dependent on genotype by genotype interactions might lead to different amounts of resources available for host and parasite reproduction. This variation in compatibility could thus mask the expected negative relationship between host and parasite fitness, as the total resource pool would not be constant. Conclusion These results highlight the importance of host variation in the determination of parasite fitness traits. This kind of interaction may in turn decouple the relationship between parasite transmission and its negative effect on host fitness, altering theoretical predictions

  5. Sex-specific association between functional neuropeptide S receptor gene (NPSR1) variants and cortisol and central stress responses.

    Science.gov (United States)

    Streit, Fabian; Akdeniz, Ceren; Haddad, Leila; Kumsta, Robert; Entringer, Sonja; Frank, Josef; Yim, Ilona S; Zänkert, Sandra; Witt, Stephanie H; Kirsch, Peter; Rietschel, Marcella; Wüst, Stefan

    2017-02-01

    The brain neuropeptide S (NPS) system has recently generated substantial interest and may be of major relevance for central stress regulation. The NPS receptor (NPSR1) is highly expressed in the limbic system, exogenous NPS exerts pronounced anxiolytic and fear-attenuating effects in rodents and extensive close crosstalk between the NPS system and the hypothalamic-pituitary-adrenal (HPA) axis has been demonstrated. In humans, associations between NPSR1 variants and anxiety and panic disorder, as well as amygdala responsiveness to fear- relevant faces and prefrontal cortex activity in a fear conditioning paradigm have been reported. Moreover, a NPSR1 sequence variant was found to be associated with cortisol stress responses in males. Here, we performed a haplotype-based analysis covering three functional NPSR1 single nucleotide polymorphisms in the promoter (rs2530547), in exon 3 (rs324981) and exon 6 (rs727162) in 277 healthy subjects who were exposed to the Trier Social Stress Test (TSST). A significant sex-specific association with salivary cortisol responses to acute psychosocial stress was detected for the common TTC haplotype 2 (frequency of about 20%). In an additional study using an imaging genetics approach, 65 healthy subjects were exposed to a stress paradigm for scanner environments (“ScanSTRESS”). We found a significant and, again, sex-specific interaction between rs324981 (whose minor T-allele is harbored by haplotype 2) and the neural stress response in a cluster close to the parahippocampal gyrus (whole brain corrected). Moreover, as in the TSST sample, NPSR1 variation was associated with salivary cortisol responses (on a trend level) in a sex-specific way. In summary, our preliminary findings in two independent cohorts exposed to different stress paradigms suggest that the NPS system significantly influences acute stress responses and that sequence variation in NPSR1 may contribute to sex differences in stress regulation. Copyright © 2016

  6. Modeling Conditional Volatility of Indian Banking Sector’s Stock Market Returns

    Directory of Open Access Journals (Sweden)

    Singh Amanjot

    2017-10-01

    Full Text Available The study attempts to capture conditional variance of Indian banking sector’s stock market returns across the years 2005 to 2015 by employing different GARCH based symmetric and asymmetric models. The results report existence of persistency as well as leverage effects in the banking sector return volatility. On an expected note, the global financial crisis increased conditional volatility in the Indian banking sector during the years 2007 to 2009; further evidenced from Markov regime switches. The exponential GARCH (EGARCH model is found to be the best fit model capturing time-varying variance in the banking sector. The results support strong implications for the market participants at the time of devising portfolio management strategies.

  7. Top 10 Research Questions Related to Youth Aerobic Fitness.

    Science.gov (United States)

    Armstrong, Neil

    2017-06-01

    Peak oxygen uptake ([Formula: see text] 2 ) is internationally recognized as the criterion measure of youth aerobic fitness, but despite pediatric data being available for almost 80 years, its measurement and interpretation in relation to growth, maturation, and health remain controversial. The trainability of youth aerobic fitness continues to be hotly debated, and causal mechanisms of training-induced changes and their modulation by chronological age, biological maturation, and sex are still to be resolved. The daily physical activity of youth is characterized by intermittent bouts and rapid changes in intensity, but physical activity of the intensity and duration required to determine peak [Formula: see text] 2 is rarely (if ever) experienced by most youth. In this context, it may therefore be the transient kinetics of pulmonary [Formula: see text] 2 that best reflect youth aerobic fitness. There are remarkably few rigorous studies of youth pulmonary [Formula: see text] 2 kinetics at the onset of exercise in different intensity domains, and the influence of chronological age, biological maturation, and sex during step changes in exercise intensity are not confidently documented. Understanding the trainability of the parameters of youth pulmonary [Formula: see text] 2 kinetics is primarily based on a few comparative studies of athletes and nonathletes. The underlying mechanisms of changes due to training require further exploration. The aims of the present article are therefore to provide a brief overview of aerobic fitness during growth and maturation, increase awareness of current controversies in its assessment and interpretation, identify gaps in knowledge, raise 10 relevant research questions, and indicate potential areas for future research.

  8. Local and sex-specific biases in crossover vs. noncrossover outcomes at meiotic recombination hot spots in mice

    Science.gov (United States)

    de Boer, Esther; Jasin, Maria; Keeney, Scott

    2015-01-01

    Meiotic recombination initiated by programmed double-strand breaks (DSBs) yields two types of interhomolog recombination products, crossovers and noncrossovers, but what determines whether a DSB will yield a crossover or noncrossover is not understood. In this study, we analyzed the influence of sex and chromosomal location on mammalian recombination outcomes by constructing fine-scale recombination maps in both males and females at two mouse hot spots located in different regions of the same chromosome. These include the most comprehensive maps of recombination hot spots in oocytes to date. One hot spot, located centrally on chromosome 1, behaved similarly in male and female meiosis: Crossovers and noncrossovers formed at comparable levels and ratios in both sexes. In contrast, at a distal hot spot, crossovers were recovered only in males even though noncrossovers were obtained at similar frequencies in both sexes. These findings reveal an example of extreme sex-specific bias in recombination outcome. We further found that estimates of relative DSB levels are surprisingly poor predictors of relative crossover frequencies between hot spots in males. Our results demonstrate that the outcome of mammalian meiotic recombination can be biased, that this bias can vary depending on location and cellular context, and that DSB frequency is not the only determinant of crossover frequency. PMID:26251527

  9. Sex-specific differences in hemodialysis prevalence and practices and the male-to-female mortality rate: the Dialysis Outcomes and Practice Patterns Study (DOPPS.

    Directory of Open Access Journals (Sweden)

    Manfred Hecking

    2014-10-01

    Full Text Available BACKGROUND: A comprehensive analysis of sex-specific differences in the characteristics, treatment, and outcomes of individuals with end-stage renal disease undergoing dialysis might reveal treatment inequalities and targets to improve sex-specific patient care. Here we describe hemodialysis prevalence and patient characteristics by sex, compare the adult male-to-female mortality rate with data from the general population, and evaluate sex interactions with mortality. METHODS AND FINDINGS: We assessed the Human Mortality Database and 206,374 patients receiving hemodialysis from 12 countries (Australia, Belgium, Canada, France, Germany, Italy, Japan, New Zealand, Spain, Sweden, the UK, and the US participating in the international, prospective Dialysis Outcomes and Practice Patterns Study (DOPPS between June 1996 and March 2012. Among 35,964 sampled DOPPS patients with full data collection, we studied patient characteristics (descriptively and mortality (via Cox regression by sex. In all age groups, more men than women were on hemodialysis (59% versus 41% overall, with large differences observed between countries. The average estimated glomerular filtration rate at hemodialysis initiation was higher in men than women. The male-to-female mortality rate ratio in the general population varied from 1.5 to 2.6 for age groups <75 y, but in hemodialysis patients was close to one. Compared to women, men were younger (mean = 61.9 ± standard deviation 14.6 versus 63.1 ± 14.5 y, were less frequently obese, were more frequently married and recipients of a kidney transplant, more frequently had coronary artery disease, and were less frequently depressed. Interaction analyses showed that the mortality risk associated with several comorbidities and hemodialysis catheter use was lower for men (hazard ratio [HR] = 1.11 than women (HR = 1.33, interaction p<0.001. This study is limited by its inability to establish causality for the observed sex-specific

  10. Neuroprotection of Sex Steroids

    Science.gov (United States)

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

    2011-01-01

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

  11. Genes, Environments, and Sex Differences in Alcohol Research.

    Science.gov (United States)

    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.

  12. Sex-specific associations between birth weight and adult primary liver cancer in a large cohort of Danish children

    DEFF Research Database (Denmark)

    Zimmermann, Esther; Berentzen, Tina L.; Gamborg, Michael

    2016-01-01

    Whether the prenatal period is critical for the development of adult primary liver cancer (PLC) is sparsely investigated. Recently, attention has been drawn to potential sex-differences in the early origins of adult disease. We investigated the association between birth weight and adult PLC...... separately in men and women, using a large cohort of 217,227 children (51% boys), born from 1936 to 1980, from the Copenhagen School Health Records Register, and followed them until 2010 in national registers. Hazard ratios (95% confidence intervals) of PLC (30 years or older) were estimated by Cox...... regression models stratified by birth cohort. During 5.1 million person-years of follow-up, 185 men and 65 women developed PLC. Sex modified the association between birth weight and adult PLC (p-value for interaction=0.0005). Compared with a sex-specific reference group of birth weights between 3.25-3.75 kg...

  13. Potential benefits of maximal exercise just prior to return from weightlessness

    Science.gov (United States)

    Convertino, Victor A.

    1987-01-01

    The purpose of this study was to determine whether performance of a single maximal bout of exercise during weightlessness within hours of return to earth would enhance recovery of aerobic fitness and physical work capacities under a 1G environment. Ten healthy men were subjected to a 10-d bedrest period in the 6-deg headdown position. A graded maximal supine cycle ergometer test was performed before and at the end of bedrest to simulate exercise during weightlessness. Following 3 h of resumption of the upright posture, a second maximal exercise test was performed on a treadmill to measure work capacity under conditions of 1G. Compared to before bedrest, peak oxygen consumption, V(O2), decreased by 8.7 percent and peak heart rate (HR) increased by 5.6 percent in the supine cycle test at the end of bedrest. However, there were no significant changes in peak V(O2) and peak HR in the upright treadmill test following bedrest. These data suggest that one bout of maximal leg exercise prior to return from 10 d of weightlessness may be adequate to restore preflight aerobic fitness and physical work capacity.

  14. Fitness for duty - a regulator's view

    International Nuclear Information System (INIS)

    Johnson, E.H.; Hall, R.E.

    1987-01-01

    Fitness for duty is a legal, moral, emotional, and political issue. It is therefore that type of issue that one would expect industry to run from, opting instead for government intervention and prescriptive regulations. This would allow the industry to hide behind the shield of doing what is necessary to comply. But fitness for duty is also a rational business issue. It involves getting a reasonable return on the investment in the people who are necessary to run the nuclear industry. It is within this context that the US Nuclear Regulatory Commission (NRC) has exercised its discretion to not undertake new rule making, instead giving the industry the mandate of pursuing this issue. The NRC has deferred rule making as long as the industry programs are effective in producing the desired results. The NRC has also retained the right to follow up on operational events and to evaluate the effectiveness of the programs in place. The industry, under the leadership of NUMARC, has risen to this challenge and has adopted the August 1985 Edison Electric Institute (EEI) fitness-for-duty program guidelines for implementation by all utilities. In evaluating the effectiveness of programs, the NRC is conducting inspections at some utilities. These inspections have confirmed that the EEI guidelines are being used as the basis for fitness-for-duty programs. Even though the nuclear industry has taken a generally strong stand on fitness for duty and has adopted reasonable guidelines for its assurance, there still remain several challenges

  15. Induced prismatic effects due to poorly fitting spectacle frames

    Directory of Open Access Journals (Sweden)

    V. R. Moodley

    2011-12-01

    toms were reported by 50% of subjects experiencing base-out, 0% base-in and 47% vertical induced prismatic effects.  However, no correlation existed between those subjects experiencing induced prism and symptoms reported.  Prism adaptation may account for some participants being asymptomatic.  Sixty three percent of subjects were not aware of the importance of properly fitted spectacle frames.  Proper optical dispensing with associated patient education is necessary to achieve optimal optical benefits of spectacles and careful attention should be given to this aspect by practitioners.  It is recommended that patients return periodically to their optometrists to have the frame alignment assessed and the fit modified if necessary. (S Afr Optom 2011 70(4 168-174

  16. Sex differences in heritability of BMI

    DEFF Research Database (Denmark)

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

    2003-01-01

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

  17. Sex-specific interaction effects of age, occupational status, and workplace stress on psychiatric symptoms and allostatic load among healthy Montreal workers.

    Science.gov (United States)

    Juster, Robert-Paul; Moskowitz, D S; Lavoie, Joel; D'Antono, Bianca

    2013-11-01

    Socio-demographics and workplace stress may affect men and women differently. The aim of this cross-sectional study was to assess sex-specific interactions among age, occupational status, and workplace Demand-Control-Support (D-C-S) factors in relation to psychiatric symptoms and allostatic load levels representing multi-systemic "wear and tear". It was hypothesized that beyond main effects, D-C-S factors would be moderated by occupational status and age in sex-specific directions predictive of subjective psychiatric symptoms and objective physiological dysregulations. Participants included healthy male (n = 81) and female (n = 118) Montreal workers aged 20 to 64 years (Men: M = 39.4 years, SD = 11.3; Women: M = 42.8 years, SD = 11.38). The Job Content Questionnaire was administered to assess workplace D-C-S factors that included psychological demands, decisional latitude, and social support. Occupational status was coded using the Nam--Powers--Boyd system derived from the Canadian census. Psychiatric symptoms were assessed using the Beck Anxiety Scale and the Beck Depression Inventory II. Sex-specific allostatic load indices were calculated based on fifteen biomarkers. Regression analyses revealed that higher social support was associated with less depressive symptoms in middle aged (p = 0.033) and older men (p = 0.027). Higher occupational status was associated with higher allostatic load levels for men (p = 0.035), while the reverse occurred for women (p = 0.048). Women with lower occupational status but with higher decision latitude had lower allostatic load levels, as did middle-aged (p = 0.031) and older women (p = 0.003) with higher psychological demands. In summary, age and occupational status moderated workplace stress in sex-specific ways that have occupational health implications.

  18. Validity of the International Fitness Scale "IFIS" in older adults.

    Science.gov (United States)

    Merellano-Navarro, Eugenio; Collado-Mateo, Daniel; García-Rubio, Javier; Gusi, Narcís; Olivares, Pedro R

    2017-09-01

    To validate the "International Fitness Scale" (IFIS) in older adults. Firstly, cognitive interviews were performed to ensure that the questionnaire was comprehensive for older Chilean adults. After that, a transversal study of 401 institutionalized and non-institutionalized older adults from Maule region in Chile was conducted. A battery of validated fitness tests for this population was used in order to compare the responses obtained in the IFIS with the objectively measured fitness performance (back scratch, chair sit-and-reach, handgrip, 30-s chair stand, timed up-and-go and 6-min walking). Indicated that IFIS presented a high compliance in the comprehension of the items which defined it, and it was able of categorizing older adults according to their measured physical fitness levels. The analysis of covariance ANCOVA adjusted by sex and age showed a concordance between IFIS and the score in physical fitness tests. Based on the results of this study, IFIS questionnaire is a good alternative to assess physical fitness in older adults. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Active release technique in hamstrings strain: Rehabilitation and return to play – a case study

    Directory of Open Access Journals (Sweden)

    Hariharasudhan Ravichandran

    2017-01-01

    Full Text Available Hamstring injuries and its rehabilitation in competitive events such as football targets safe and early return to play. This is because hamstring injuries are more related to prolonged recovery time and high rate of re-injury. In this case study, Zakeer Mundampara, 26-year-old footballer of Chennaiyin FC team (Indian super league tournament, who was rehabilitated for Grade 2 hamstring strain was briefed. To describe the importance of conservative rehabilitation in hamstring injuries and report on player's rehabilitation program and clinical outcome. Zakeer Mundampara was conservatively treated with active release technique for 2 weeks duration. Data collected includes passive knee extension test range of motion and verbal rating score. After 2 weeks of rehabilitation, Zakeer Mundampara had nearly full range of pain-free movement, normal gait and trained to run safely. By the 3rd week, he started to perform all sports specific drills. He was rehabilitated and set fit to play after 4 weeks from the date of injury. Active release technique is effective in hamstring injuries. In this case study, rehabilitation program with an emphasis on active release technique is found to be effective in returning the footballer back to play.

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

    Science.gov (United States)

    McMillan, Karen; Worth, Heather; Rawstorne, Patrick

    2018-07-01

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

  1. Plumage polymorphism and fitness in Swainson's hawks.

    Science.gov (United States)

    Briggs, C W; Collopy, M W; Woodbridge, B

    2011-10-01

    We examine the maintenance of a plumage polymorphism, variation in plumages among the same age and sex class within a population, in a population of Swainson's Hawks. We take advantage of 32 years of data to examine two prevalent hypotheses used to explain the persistence of morphs: apostatic selection and heterozygous advantage. We investigate differences in fitness among three morph classes of a melanistic trait in Swainson's Hawks: light (7% of the local breeding population), intermediate (57%) and dark (36%). Specifically, we examined morph differences in adult apparent survival, breeding success, annual number of fledglings produced, probability of offspring recruitment into the breeding population and lifetime reproductive success (LRS). If apostatic selection were a factor in maintaining morphs, we would expect that individuals with the least frequent morph would perform best in one or more of these fitness categories. Alternatively, if heterozygous advantage played a role in the maintenance of this polymorphism, we would expect heterozygotes (i.e. intermediate morphs) to have one or more increased rates in these categories. We found no difference in adult apparent survival between morph classes. Similarly, there were no differences in breeding success, nest productivity, LRS or probability of recruitment of offspring between parental morph. We conclude that neither apostatic selection nor heterozygous advantage appear to play a role in maintaining morphs in this population. © 2011 The Authors. Journal of Evolutionary Biology © 2011 European Society For Evolutionary Biology.

  2. Sex-specific sleep patterns among university students in Lebanon: impact on depression and academic performance.

    Science.gov (United States)

    Kabrita, Colette S; Hajjar-Muça, Theresa A

    2016-01-01

    Good sleep quality and quantity are fundamental to the maintenance of normal physiological processes. Changes in sleep patterns are commonly observed among young adults and are shown to impact neurocognitive, academic, and psychological well-being. Given the scarcity of sleep information about Lebanon and acknowledging the sex differences in various sleep dimensions, we conducted a study that aimed at assessing sex differences in sleep habits among university students in Lebanon in relation to psychoacademic status. A total of 540 students (50.6% females) completed a questionnaire that inquired about sociodemographics and evaluated sleep quality and depression using the Pittsburg Sleep Quality Index (PSQI) and Center for Epidemiological Studies Depression Scale (CES-D), respectively. The mean PSQI global score (6.57±3.49) indicated poor sleep, with no significant differences between men and women. The sleep/wake rhythm was delayed on weekends for both sexes. Females exhibited earlier bedtimes and rise times and longer sleep durations on both weekdays and weekends. However, unlike males females showed a greater phase delay in wake times than bedtimes on weekends (149 minutes vs 74 minutes, respectively). In all, 70.9% of females suffered from depressive symptoms, which was a significantly higher proportion compared with 58.5% of males (Pacademic performance of females was significantly better than that of males (2.8±0.61 vs 2.65±0.61, Psleep duration (r=-0.221, Psleep timing, such as bedtime/rise time and nocturnal sleep duration, rather than sleep quality exist among Lebanese university students. Sex-specific sleep patterns have differential impact on psychological and academic well-being.

  3. Woman's Profession and Female Role--The Development of Sex-specific Structures of Education and of the Labor Market before the First World War.

    Science.gov (United States)

    Klinger, Vera

    1989-01-01

    Examines the intrusion of female employees into the traditionally male domain of office work from 1860 to 1914. Shows that sex-specific segregation was supported by a lack of training facilities for girls and by fact that these facilities supported the dominant sex-role structure. Focuses on the development of vocational schools for girls.…

  4. What Physical Fitness Component Is Most Closely Associated With Adolescents' Blood Pressure?

    Science.gov (United States)

    Nunes, Heloyse E G; Alves, Carlos A S; Gonçalves, Eliane C A; Silva, Diego A S

    2017-12-01

    This study aimed to determine which of four selected physical fitness variables, would be most associated with blood pressure changes (systolic and diastolic) in a large sample of adolescents. This was a descriptive and cross-sectional, epidemiological study of 1,117 adolescents aged 14-19 years from southern Brazil. Systolic and diastolic blood pressure were measured by a digital pressure device, and the selected physical fitness variables were body composition (body mass index), flexibility (sit-and-reach test), muscle strength/resistance (manual dynamometer), and aerobic fitness (Modified Canadian Aerobic Fitness Test). Simple and multiple linear regression analyses revealed that aerobic fitness and muscle strength/resistance best explained variations in systolic blood pressure for boys (17.3% and 7.4% of variance) and girls (7.4% of variance). Aerobic fitness, body composition, and muscle strength/resistance are all important indicators of blood pressure control, but aerobic fitness was a stronger predictor of systolic blood pressure in boys and of diastolic blood pressure in both sexes.

  5. Is sex an indicator of prognosis after mild traumatic brain injury

    DEFF Research Database (Denmark)

    Cancelliere, Carol; Donovan, James; David Cassidy, J.

    2016-01-01

    . Most studies did not find a sex difference for postconcussion symptoms in children and adults. No sex difference was found for risk of dementia and primary brain tumor, return to work, or posttraumatic stress syndrome. Conclusions Sex is not a well-studied prognostic indicator for recovery after MTBI......Objective to determine sex differences in the recovery and prognosis after mild traumatic brain injury (MTBI) in adults and children. Data Sources We analyzed all scientifically admissible primary studies in the World Health Organization (WHO) (n=120) and International Collaboration on Mild...... Traumatic Brain Injury Prognosis (ICoMP) (n=101) systematic reviews regarding prognosis of MTBI for sex-stratified findings. They searched MEDLINE and other databases from 1980 through 2000 (WHO) and 2001 through 2012 (ICoMP) for published, peer-reviewed reports in English and other languages. Study...

  6. Physical Fitness and Serum Vitamin D and Cognition in Elderly Koreans.

    Science.gov (United States)

    Ahn, Jeong-Deok; Kang, Hyunsik

    2015-12-01

    Poor physical fitness and low serum vitamin D are known to be modifiable risk factors for cognitive declines with normal aging. We investigated the association of physical fitness and serum vitamin D levels with global cognitive function in older adults. In this cross-sectional study, a total of 412 older Korean adults (108 men aged 74.4 ± 6.0 years and 304 women aged 73.1 ± 5.4 years) completed the Korean version of Mini-Mental State Examination (MMSE) to assess global cognitive performance and the senior fitness test to assess strength, flexibility, agility, and endurance domains of physical fitness. Body mass index, percent body fat, serum vitamin D, geriatric depression scale (GDS), level of education, smoking, and history of cardiovascular or cerebrovascular disease were also assessed as covariates. Age, sex, GDS, and body fatness were negatively associated with MMSE-based cognitive performance. Serum vitamin D and physical fitness were positively associated with MMSE-based cognitive performance. Multivariate linear regression showed that agility (partial R(2) = -0.184, p = 0.029) and endurance (partial R(2) = 0.191, p = 0.022) domains of physical fitness along with serum vitamin D (partial R(2) = 0.210, p = 0.012) were significant predictors for global cognitive performance after controlling for covariates (i.e., age, sex, education, GDS, body fatness, and comorbidity index). The current findings of the study suggest that promotion of physical fitness and vitamin D supplementation should be key components of interventions to prevent cognitive decline with normal aging. Key pointsCognitive declines are associated with normal aging as well as modifiable lifestyle risk factors, and there is an increasing need to identify the modifiable risk factors for the onset of cognitive declines and to provide evidence-based strategies for healthy and successful aging.In Korea, little is known about the relationships of physical fitness and serum vitamin D with cognitive

  7. Sex-specific differences in mitochondria biogenesis, morphology, respiratory function, and ROS homeostasis in young mouse heart and brain.

    Science.gov (United States)

    Khalifa, Abdel Rahman M; Abdel-Rahman, Engy A; Mahmoud, Ali M; Ali, Mohamed H; Noureldin, Maha; Saber, Saber H; Mohsen, Mahmoud; Ali, Sameh S

    2017-03-01

    Sex-specific differences in mitochondrial function and free radical homeostasis are reported in the context of aging but not well-established in pathogeneses occurring early in life. Here, we examine if sex disparity in mitochondria function, morphology, and redox status starts early and hence can be implicated in sexual dimorphism in cardiac as well as neurological disorders prevalent at young age. Although mitochondrial activity in the heart did not significantly vary between sexes, female brain exhibited enhanced respiration and higher reserve capacity. This was associated with lower H 2 O 2 production in female cardiac and brain tissues. Using transmission electron microscopy, we found that the number of female cardiac mitochondria is moderately greater (117 ± 3%, P  = 0.049, N  = 4) than male's, which increased significantly for cortical mitochondria (134 ± 4%, P  = 0.001, N  = 4). However, male's cardiac mitochondria exhibited fragmented, circular, and smaller mitochondria relative to female's mitochondria, while no morphologic sex-dependent differences were observed in cortical mitochondria. No sex differences were detected in Nox2 and Nox4 proteins or O 2 -consuming/H 2 O 2 -producing activities in brain homogenate or synaptosomes. However, a strong trend of increased EPR-detected NOX superoxide in male synaptosomes hinted at higher superoxide dismutase activity in female brains, which was confirmed by two independent protocols. We also provide direct evidence that respiring mitochondria generally produce an order-of-magnitude lower reactive oxygen species (ROS) proportions than currently estimated. Our results indicate that sex differences in mitochondrial biogenesis, bioenergetics, and morphology may start at young age and that sex-dependent SOD capacity may be responsible for differences in ROS homeostasis in heart and brain. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological

  8. Adolescents show sex-specific preferences on media when pornography is a major source of sexual knowledge

    DEFF Research Database (Denmark)

    Rasmussen, Anna Lund; Svarrer, Rebekka; Lauszus, Finn Friis

    2017-01-01

    photographs;thus, these magazines constituted a major source of adolescent girls. Girls knew the gestational age of legal abortion in Denmark and had their knowledge from non-explicit magazines while this was not the case for boys (p=0.004). Pupils who stated their knowledge on sex from these magazines knew...... the first sign of pregnancy (menostasia), the correct facts of legal abortion, and STI.Conclusions: Pornography in different media is used in the vast majority of adolescents and its use is sex-specific. Knowledge on STI, pregnancy, legal abortion was variably associated with the type of media....... with focus on pornography and what media was used. Pornography was divided according to five media subcategories. Knowledge on sexually transmitted infection (STI), pregnancy and abortion and their associations with pornography were explored.Results: Pornography was reported as the second largest source...

  9. Sex-Specific Sociodemographic Correlates of Dietary Patterns in a Large Sample of French Elderly Individuals

    Directory of Open Access Journals (Sweden)

    Valentina A. Andreeva

    2016-08-01

    Full Text Available This cross-sectional analysis provides up-to-date information about dietary patterns (DP and their sociodemographic correlates in European elderly individuals. We studied 6686 enrollees aged 65+ (55% women in the ongoing French population-based NutriNet-Santé e-cohort. Diet was assessed via three 24 h records. The sex-specific correlates of factor analysis derived DP were identified with multivariable linear regression. Using 22 pre-defined food groups, three DP were extracted. The “healthy” DP (fruit, vegetables, grains, nuts, fish was positively associated with education, living alone, and being a former smoker (women, and negatively associated with being overweight, current smoker (men, age 75+ years, having hypertension, and obesity (women. The “western” DP (meat, appetizers, cheese, alcohol was positively associated with BMI (men and being a former/current smoker; it was negatively associated with age 75+ years (women and living alone. The “traditional” DP (bread, potatoes, milk, vegetables, butter, stock was positively associated with age and negatively associated with being a former/current smoker, education (men, and residing in an urban/semi-urban area. The findings support the diversity of DP among the elderly, highlighting sex-specific differences. The “healthy” DP explained the largest amount of variance in intake. Future studies could replicate the models in longitudinal and international contexts.

  10. Return to sport after shoulder arthroplasty: a systematic review and meta-analysis.

    Science.gov (United States)

    Liu, Joseph N; Steinhaus, Michael E; Garcia, Grant H; Chang, Brenda; Fields, Kara; Dines, David M; Warren, Russell F; Gulotta, Lawrence V

    2018-01-01

    With increasing incidence and indications for shoulder arthroplasty, there is an increasing emphasis on the ability to return to sports. The main goal of this study was to determine the rate of return to sport after shoulder arthroplasty. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed to perform this systematic review and meta-analysis. A search was performed on MEDLINE, Scopus, EMBASE, and the Cochrane Library. The quality of the included studies was evaluated according to the Methodological Index for Nonrandomized Studies checklist. The main judgement outcome was the rate of return to sports activity after shoulder arthroplasty and the level of play upon return (identical or higher/lower level). Thirteen studies were reviewed, including 944 patients (506 athletes), treated with shoulder arthroplasty at an average follow-up of 5.1 years (range, 0.5-12.6 years). The most common sports were swimming (n = 169), golf (n = 144), fitness sports (n = 71), and tennis (n = 63). The overall rate of return to sport was 85.1% (95% CI, 76.5-92.3%), including 72.3% (95% CI, 60.6-82.8%) returning to an equivalent or improved level of play, after 1-36 months. Patients undergoing anatomic total shoulder arthroplasty returned at a significantly higher rate (92.6%) compared to hemiarthroplasty (71.1%, p = 0.02) or reverse total shoulder arthroplasty (74.9%, p = 0.003). Most patients are able to return to one or more sports following shoulder arthroplasty, with anatomic total shoulder arthroplasty having the highest rate of return. IV.

  11. Evolution of sex-biased maternal effects in birds: I. Sex-specific resource allocation among simultaneously growing oocytes.

    Science.gov (United States)

    Young, R L; Badyaev, A V

    2004-11-01

    Females in species that produce broods of multiple offspring need to partition resources among simultaneously growing ova, embryos or neonates. In birds, the duration of growth of a single egg exceeds the ovulation interval, and when maternal resources are limited, a temporal overlap among several developing follicles in the ovary might result in a trade-off of resources among them. We studied growth of oocytes in relation to their future ovulation order, sex, and overlap with other oocytes in a population of house finches (Carpodacus mexicanus) where strongly sex-biased maternal effects are favoured by natural selection. We found pronounced differences in growth patterns between oocytes that produced males and females. Male oocytes grew up to five times faster and reached their ovulation size earlier than female oocytes. Early onset and early termination of male oocytes' growth in relation to their ovulation resulted in their lesser temporal overlap with other growing ova compared with female oocytes. Consequently, ovulation mass of female but not male oocytes was strongly negatively affected by temporal overlap with other oocytes. In turn, mass of male oocytes was mostly affected by the order of ovulation and by maternal incubation strategy. These results provide a mechanism for sex-biased allocation of maternal resources during egg formation and provide insights into the timing of the sex-determining meiotic division in relation to ovulation in this species.

  12. The impact of violence on sex risk and drug use behaviors among women engaged in sex work in Phnom Penh, Cambodia.

    Science.gov (United States)

    Draughon Moret, Jessica E; Carrico, Adam W; Evans, Jennifer L; Stein, Ellen S; Couture, Marie-Claude; Maher, Lisa; Page, Kimberly

    2016-04-01

    Violence, substance use, and HIV disproportionately impact female entertainment and sex workers (FESW), but causal pathways remain unclear. We examined data from an observational cohort of FESW age 15-29 in Phnom Penh, Cambodia for associations between violence exposure and sexual risk and drug use. Validated measures of physical and sexual violence were assessed at baseline. Self-reported outcomes measured quarterly over the next 12-months included past month sexual partners, consistent condom use by partner type, sex while high, and amphetamine type stimulant (ATS) use. Biomarkers measured quarterly included prostate specific antigen (PSA) and urine toxicology. Generalized estimating equations were fit adjusting for age, education, marital status and sex work venue. Of 220 women, 48% reported physical or sexual violence in the preceding 12-months. Physical violence was associated with increased number of sex partners (adjusted incidence rate ratio [aIRR] 1.33; 95% CI: 1.04-1.71), greater odds of sex while high (adjusted odds ratio [aOR] 2.42; 95% CI: 1.10-5.33), increased days of ATS use (aIRR 2.74; 95% CI: 1.29-5.84) and increased odds of an ATS+ urine screen (aOR 2.80, 95%CI: 1.38-5.66). Sexual violence predicted decreased odds of consistent condom use with non-paying partners (aOR 0.24; 95% CI: 0.10-0.59) and greater odds of a PSA+ vaginal swab (aOR 1.83; 95% CI: 1.13-2.93). Physical and sexual violence are prevalent among Cambodian FESW and associated with subsequent sexual risk and drug use behaviors. Clinical research examining interventions targeting structural and interpersonal factors impacting violence is needed to optimize HIV/AIDS prevention among FESW. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  13. Estimating the Ex Ante Expected Returns to College

    OpenAIRE

    Andrew J. Hussey; Omari H. Swinton

    2011-01-01

    Rather than estimating the returns to obtaining a college degree, this paper treats the college education decision as an uncertain investment involving varying likelihoods of successful graduation. We predict earnings conditional on both graduating and not graduating from both selective and non-selective institutions, and incorporate estimated individual-specific graduation rates in calculating the ex ante expected returns from college attendance for individuals across the ability distributio...

  14. Returning to work - a long-term process reaching beyond the time frames of multimodal non-specific back pain rehabilitation.

    Science.gov (United States)

    Hellman, Therese; Jensen, Irene; Bergström, Gunnar; Busch, Hillevi

    2015-01-01

    To explore and describe health professionals' experience of working with return to work (RTW) in multimodal rehabilitation for people with non-specific back pain. An interview study using qualitative content analysis. Fifteen participants were interviewed, all were working with multimodal rehabilitation for people with non-specific back pain in eight different rehabilitation units. The participants experienced RTW as a long-term process reaching beyond the time frames of the multimodal rehabilitation (MMR). Their attitudes and, their patients' condition, impacted on their work which focused on psychological and physical well-being as well as participation in everyday life. They often created an action plan for the RTW process, however the responsibility for its realisation was transferred to other actors. The participants described limited interventions in connection with patients' workplaces. Recommended support in the RTW process in MMR comprises the provision of continuous supervision of vocational issues for the health care professionals, the development of guidelines and a checklist for how to work in close collaboration with patients' workplaces and employers, the provision of long-term follow-up in relation to the patients' work, and the development of proper interventions in order to promote transitions between all the different actors involved. Rehabilitation programs targeting return to work (RTW) for people with non-specific back pain needs to include features concretely focusing on vocational issues. Health and RTW is often seen as a linear process in which health comes before RTW. Rehabilitation programs could be tailored to better address the reciprocal relationship between health and work, in which they are interconnected and affect each other. The RTW process is reaching beyond the time frames of the multimodal rehabilitation but further support from the patients are asked for. The rehabilitation programs needs to be designed to provide long

  15. Sex and age differences in physical performance: A comparison of Army basic training and operational populations.

    Science.gov (United States)

    Dada, Esther O; Anderson, Morgan K; Grier, Tyson; Alemany, Joseph A; Jones, Bruce H

    2017-11-01

    To determine the age- and sex-specific differences of physical fitness performances and Body Mass Index (BMI) in basic training and the operational Army. Cross-sectional Study. This secondary analysis utilizes retrospective surveys of U.S. Army Soldiers in Basic Combat Training (BCT) and operational units to compare physical performances between men and women as measured by the Army Physical Readiness Test (APFT). An ANOVA was used to compare mean differences in APFT results and BMI within sex-specific populations. A post hoc Tukey test identified specific mean differences. Adjusting for age, an ANCOVA was used to compare sex and occupation (infantry and non-infantry) differences in APFT results. Surveyed populations consisted of 2216 BCT Soldiers (1573 men and 643 women) and 5515 Operational Soldiers (4987 men and 528 women). Male and female operational Soldiers had greater muscular performance (79%-125% higher APFT push-ups, 66%-85% higher APFT sit-ups) and cardiorespiratory performance (22%-24% faster APFT 2-mile run times) than BCT Soldiers. Male BCT and operational Soldiers outperform their female counterparts on tests of muscular and cardiorespiratory endurance. Sex differences in physical performances attenuated among female Soldiers in operational units compared to BCT. Among male operational Soldiers, infantry Soldiers exhibited greater cardiorespiratory and muscular performance than non-infantry Soldiers. Higher BMI was associated with higher age groups, except for female BCT Soldiers. Gaps in cardiorespiratory and muscular performances between men and women should be addressed through targeted physical training programs that aim to minimize physiological differences. Published by Elsevier Ltd.

  16. Assessment of self-perception of physical fitness and proposal for standards among Chilean adolescent students: the EAPAF study.

    Science.gov (United States)

    Cossio-Bolaños, Marco; Vasquez, Pablo; Luarte-Rocha, Cristian; Sulla-Torres, José; Gómez Campos, Rossana

    2016-08-01

    Physical fitness may be assessed among children and adolescents in a quantitative and qualitative manner. At present, in Chile, there are no tools available to assess self-perception of physical fitness. Therefore, the purpose of this study was to develop a valid and reliable instrument that would allow to assess selfperception of physical fitness among adolescents and propose standards for age and sex. A survey was administered among adolescent students from six public schools in the Maule Region, Chile, selected in a probabilistic (stratified) fashion. To measure self-perception of physical fitness, a qualitative instrument was developed: the Self-Perception of Physical Fitness Scale (EAPAF, escala de autopercepcion de la aptitud fisica), which is made up of four dimensions and 18 questions. The LMS method (L: Box-Cox coefficient, M: median curve, and S: variation coefficient) was used to establish percentiles and propose references by dimension, age and sex. A total of 3060 adolescents (1702 boys and 1358 girls) aged 11.0 to 18.9 years old were included. The factor analysis evidenced four factors. Saturation values were above 0.40. The percentage of instrument explanation reached 54.24%. In terms of reliability, the 18 questions reflected that Cronbach's alpha was between 0.82 and 0.85. Percentiles (p15, p50 and p85) were developed to classify self-perception of physical fitness by dimension, age and sex. Boys showed higher scores in the self-perception of physical fitness scale when compared to girls (p 〈 0.001). The instrument developed in this study was valid and reliable. In addition, the standards proposed may become a useful tool to classify adolescents in relation to their selfperception of physical fitness. Sociedad Argentina de Pediatría.

  17. A Review of The Sex EDcyclopedia

    Science.gov (United States)

    Herman, Jeff; Andelloux, Megan

    2012-01-01

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

  18. Sex-Specific Effects of Combined Exposure to Chemical and Non-chemical Stressors on Neuroendocrine Development: a Review of Recent Findings and Putative Mechanisms.

    Science.gov (United States)

    Cowell, Whitney J; Wright, Rosalind J

    2017-12-01

    Environmental toxicants and psychosocial stressors share many biological substrates and influence overlapping physiological pathways. Increasing evidence indicates stress-induced changes to the maternal milieu may prime rapidly developing physiological systems for disruption by concurrent or subsequent exposure to environmental chemicals. In this review, we highlight putative mechanisms underlying sex-specific susceptibility of the developing neuroendocrine system to the joint effects of stress or stress correlates and environmental toxicants (bisphenol A, alcohol, phthalates, lead, chlorpyrifos, and traffic-related air pollution). We provide evidence indicating that concurrent or tandem exposure to chemical and non-chemical stressors during windows of rapid development is associated with sex-specific synergistic, potentiated and reversed effects on several neuroendocrine endpoints related to hypothalamic-pituitary-adrenal axis function, sex steroid levels, neurotransmitter circuits, and innate immune function. We additionally identify gaps, such as the role that the endocrine-active placenta plays, in our understanding of these complex interactions. Finally, we discuss future research needs, including the investigation of non-hormonal biomarkers of stress. We demonstrate multiple physiologic systems are impacted by joint exposure to chemical and non-chemical stressors differentially among males and females. Collectively, the results highlight the importance of evaluating sex-specific endpoints when investigating the neuroendocrine system and underscore the need to examine exposure to chemical toxicants within the context of the social environment.

  19. Sex matters: The effects of biological sex on adipose tissue biology and energy metabolism

    Directory of Open Access Journals (Sweden)

    Teresa G. Valencak

    2017-08-01

    Full Text Available Adipose tissue is a complex and multi-faceted organ. It responds dynamically to internal and external stimuli, depending on the developmental stage and activity of the organism. The most common functional subunits of adipose tissue, white and brown adipocytes, regulate and respond to endocrine processes, which then determine metabolic rate as well as adipose tissue functions. While the molecular aspects of white and brown adipose biology have become clearer in the recent past, much less is known about sex-specific differences in regulation and deposition of adipose tissue, and the specific role of the so-called pink adipocytes during lactation in females. This review summarises the current understanding of adipose tissue dynamics with a focus on sex-specific differences in adipose tissue energy metabolism and endocrine functions, focussing on mammalian model organisms as well as human-derived data. In females, pink adipocytes trans-differentiate during pregnancy from subcutaneous white adipocytes and are responsible for milk-secretion in mammary glands. Overlooking biological sex variation may ultimately hamper clinical treatments of many aspects of metabolic disorders. Keywords: Body fatness, Adipose tissue, Sex-specific differences, Adipokines, Adipocytes, Obesity, Energy metabolism

  20. A Review of New and Developing Technology to Significantly Improve Mars Sample-Return Missions

    Science.gov (United States)

    Carsey, F.; Brophy, J.; Gilmore, M.; Rodgers, D.; Wilcox, B.

    2000-07-01

    A JPL development activity was initiated in FY 1999 for the purpose of examining and evaluating technologies that could materially improve future (i.e., beyond the 2005 launch) Mars sample return missions. The scope of the technology review was comprehensive and end-to-end; the goal was to improve mass, cost, risk, and scientific return. A specific objective was to assess approaches to sample return with only one Earth launch. While the objective of the study was specifically for sample-return, in-situ missions can also benefit from using many of the technologies examined.

  1. Consumer returns policies with endogenous deadline and supply chain coordination

    DEFF Research Database (Denmark)

    Xu, Lei; Li, Yongjian; Govindan, Kannan

    2015-01-01

    on consumers' behavior and the pricing and inventory policies of the retailer are systematically investigated. Moreover, based on the analysis of consumer return behavior on a traditional buy-back contract, we present a new differentiated buy-back contract, contingent on return deadline, to coordinate a supply......This paper considers returns policies under which consumers' valuation depends on the refund amount they receive and the length of time theymustwait after the item is returned. Consumers face an uncertain valuation before purchase, and the realization of that purchase's value occurs only after...... chain consisting of an upstream manufacturer and a downstream retailer. Finally, extensions on some specific behavioral factors such as moral hazard, inertia return, and external effect are investigated....

  2. Sex differences, endogenous sex-hormone hormones, sex-hormone binding globulin, and exogenous disruptors in diabetes and related metabolic outcomes.

    Science.gov (United States)

    Liu, Simin; Sun, Qi

    2016-12-19

    In assessing clinical and pathophysiological development of type 2 diabetes (T2D), the critical role of the sex steroids axis is underappreciated, particularly concerning the sex-specific relationships with many relevant cardiometabolic outcomes. In this issue of the Journal of Diabetes, we provide a comprehensive overview of these significant associations of germline variants in the genes governing the sex steroid pathways, plasma levels of steroid hormones, and sex hormone-binding globulin (SHBG) with T2D risk that have been observed in many clinical and high-quality large prospective cohorts of men and women across ethnic populations. Together, this body of evidence indicates that sex steroids and SHBG should be routinely incorporated into clinical characterization of T2D patients, particularly in screening prediabetic patients, such as those with metabolic syndrome, using plasma levels of SHBG. Given that several germline mutations in the SHBG gene have also been directly related to both plasma concentrations of SHBG and clinical manifestation of T2D, targeting signals in the sex steroid axis, particularly SHBG, may have significant utility in the prediction and treatment of T2D. Further, many of the environmental endocrine disrupting chemicals may exert their potential adverse effects on cardiometabolic outcomes via either estrogenic or androgenic signaling pathways, highlighting the importance of using the sex steroids and SHBG as important biochemical markers in both clinical and population studies in studying sex-specific mechanisms in the pathogenesis of T2D and its complications, as well as the need to equitably allocate resources in studying both men and women. © 2016 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.

  3. Sex-specific differential survival of extra-pair and within-pair offspring in song sparrows, Melospiza melodia.

    Science.gov (United States)

    Sardell, Rebecca J; Arcese, Peter; Keller, Lukas F; Reid, Jane M

    2011-11-07

    It is widely hypothesized that the evolution of female extra-pair reproduction in socially monogamous species reflects indirect genetic benefits to females. However, a critical prediction of this hypothesis, that extra-pair young (EPY) are fitter than within-pair young (WPY), has rarely been rigorously tested. We used 18 years of data from free-living song sparrows, Melospiza melodia, to test whether survival through major life-history stages differed between EPY and WPY maternal half-siblings. On average, survival of hatched chicks to independence from parental care and recruitment, and their total lifespan, did not differ significantly between EPY and WPY. However, EPY consistently tended to be less likely to survive, and recruited EPY survived for significantly fewer years than recruited WPY. Furthermore, the survival difference between EPY and WPY was sex-specific; female EPY were less likely to survive to independence and recruitment and lived fewer years than female WPY, whereas male EPY were similarly or slightly more likely to survive and to live more years than male WPY. These data indicate that extra-pair paternity may impose an indirect cost on females via their female offspring and that sex-specific genetic, environmental or maternal effects may shape extra-pair reproduction.

  4. Population specific fitness response of Drosophila subobscura to lead pollution.

    Science.gov (United States)

    Kenig, Bojan; Stamenković-Radak, Marina; Andelković, Marko

    2013-04-01

    Differences in heavy metal tolerance among separate populations of the same species have often been interpreted as local adaptation. Persistence of differences after removing the stressor indicates that mechanisms responsible for the increased tolerance were genetically determined. Drosophila subobscura Collin (Diptera: Drosophilidae) populations were sampled from two localities with different history of heavy metal pollution, and reared for eight generations in the laboratory on a standard medium and on media with different concentrations of lead (Pb). To determine whether flies from different natural populations exposed to the Pb-contaminated media in the laboratory show population specific variability in fitness components over generations, experimental groups with different concentrations of lead were assayed in three generations (F2 , F5 , and F8 ) for fecundity, developmental time, and egg-to-adult viability. On the contaminated medium, fecundity was reduced in later generations and viability was increased, irrespective of the environmental origin of populations. For both populations, developmental time showed a tendency of slowing down on media with lead. Faster development was observed in later generations. Preadaptation to contamination, meaning higher fecundity, higher viability, and faster egg to adult development in all studied generations, was found in D. subobscura originating from the locality with a higher level of heavy metal pollution. © 2012 The Authors Insect Science © 2012 Institute of Zoology, Chinese Academy of Sciences.

  5. Youth fitness--problems and solutions.

    Science.gov (United States)

    DiNubile, N A

    1993-07-01

    Review of the current data in the area of youth fitness reveals some alarming trends. Children in the United States are fatter, slower, and weaker than their counterparts in other developed nations. In addition, U.S. children seem to be adopting a sedentary lifestyle at earlier ages. Although there is no easy solution to this problem, there are specific recommendations that can ensure improvement in this area. The cornerstone for any meaningful change must involve programs that seek to increase physical activity both in school and at home. Daily, quality physical education in grades K-12 should be mandated in all states. Parents should be educated regarding the critical importance and the multitude of benefits to be derived from their involvement in fitness-related activities with their children. A healthy balance must be established between sedentary activities, e.g., television and video games, and physical activity. All schools should establish fitness testing programs for children and these should be based on health-fitness parameters rather than on athletic performance variables. To ensure improvements in youth fitness across our nation, other interventions are also necessary. These include appropriate involvement of local communities, state and federal governments, the medical health professions, and the media. Specific strategies are available for each group.

  6. Sex-specific biotransformation and detoxification after xenobiotic exposure of primary cultured hepatocytes of European flounder (Platichthys flesus L.)

    NARCIS (Netherlands)

    Winzer, Katja; van Noorden, Cornelis J. F.; Köhler, Angela

    2002-01-01

    Sex-specific effects of sublethal concentrations of known effective pro-oxidants such as 100, 200 and 400 muM benzo[a]pyrene (B[a]p), 50 M nitrofurantoin (NF) and 100 muM hydrogen peroxide (H2O2) on biotransformation pathways were studied in isolated hepatocytes of immature female and male European

  7. Preconception sex selection for non-medical and intermediate reasons: ethical reflections

    OpenAIRE

    de Wert, G.; Dondorp, W.

    2010-01-01

    Sex selection for non-medical reasons is forbidden in many countries. Focusing on preconception sex selection, the authors first observe that it is unclear what should count as a ‘medical reason’ in this context and argue for the existence of ‘intermediate reasons’ that do not fit well within the rigid distinction between ‘medical’and ‘non-medical’. The article further provides a critical review of the arguments for the prohibition of sex selection for non-medical reasons and finds that none ...

  8. Demographic, psychometric, and case progression information as predictors of return-to-work in teachers undergoing occupational rehabilitation.

    Science.gov (United States)

    Young, A E; Russell, J

    1995-12-01

    Occupational stress is a significant problem and is of particular concern for educational organizations. It was the aim of the current project to identify variables that could predict return-to-work outcomes in a group of teachers who had taken leave for a work-related stress condition. Demographic, psychometric, and case progression data were collected for 119 teachers who had taken Workers' Compensation Leave and were participating in a rehabilitation program. The participants' return to work outcomes were followed-up at least 12 months after they initially left their workplace. Hierarchical discriminant function analysis indicated that 84.62% of the cases could be correctly classified as either "returning to work" or "not returning to work due to illness." The main predictor variables were: if the individual had attempted to return to work within 505 days of injury, the individual's health behaviors, the sex of the individual, and the type of school in which he or she was employed (primary or secondary). It is suggested that the derived model could be further developed and used to predict return to work from stress-related illnesses.

  9. Sex reversal in vertebrates

    OpenAIRE

    2016-01-01

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

  10. Avian sex, sex chromosomes, and dosage compensation in the age of genomics.

    Science.gov (United States)

    Graves, Jennifer A Marshall

    2014-04-01

    Comparisons of the sex chromosome systems in birds and mammals are widening our view and deepening our understanding of vertebrate sex chromosome organization, function, and evolution. Birds have a very conserved ZW system of sex determination in which males have two copies of a large, gene-rich Z chromosome, and females have a single Z and a female-specific W chromosome. The avian ZW system is quite the reverse of the well-studied mammalian XY chromosome system, and evolved independently from different autosomal blocs. Despite the different gene content of mammal and bird sex chromosomes, there are many parallels. Genes on the bird Z and the mammal X have both undergone selection for male-advantage functions, and there has been amplification of male-advantage genes and accumulation of LINEs. The bird W and mammal Y have both undergone extensive degradation, but some birds retain early stages and some mammals terminal stages of the process, suggesting that the process is more advanced in mammals. Different sex-determining genes, DMRT1 and SRY, define the ZW and XY systems, but DMRT1 is involved in downstream events in mammals. Birds show strong cell autonomous specification of somatic sex differences in ZZ and ZW tissue, but there is growing evidence for direct X chromosome effects on sexual phenotype in mammals. Dosage compensation in birds appears to be phenotypically and molecularly quite different from X inactivation, being partial and gene-specific, but both systems use tools from the same molecular toolbox and there are some signs that galliform birds represent an early stage in the evolution of a coordinated system.

  11. Sex impacts the relation between body composition and physical function in older adults.

    Science.gov (United States)

    Valentine, Rudy J; Misic, Mark M; Rosengren, Karl S; Woods, Jeffrey A; Evans, Ellen M

    2009-01-01

    To determine the sex-specific relationships between physical activity, aerobic fitness, adiposity (%Fat), mineral-free lean mass (MFLM), and balance and gait performance in older adults. Eighty-five female and 49 male sedentary, healthy, community-dwelling older adults (mean [SD] age, 69.6 [5.4] and 70.3 [4.7] years, respectively) were evaluated on habitual physical activity via questionnaire, aerobic fitness by a maximal oxygen consumption treadmill test, whole and regional body composition by dual-energy x-ray absorptiometry, and lower extremity physical function using gait tasks and computerized dynamic posturography. As expected, men had less body fat, more lean mass, and higher aerobic fitness than did women and tended to perform better on all lower extremity physical function tasks (all P 0.50, all P women (r = -0.38, P men. Neither fitness nor body composition was related to balance in men, whereas in women, leg MFLM was positively associated (r = 0.27, P Women, but not men, with a greater ratio of body weight to leg MFLM performed worse on gait tasks (P women are more strongly affected by alterations in body composition. Lower %Fat and preservation of lower body lean mass have important implications for reducing the risk of physical disability, especially in older women.

  12. A pair-matched comparison of return to pivoting sports at 1 year in ACL-injured patients after a nonoperative versus operative treatment course

    Science.gov (United States)

    Grindem, Hege; Eitzen, Ingrid; Moksnes, Håvard; Snyder-Mackler, Lynn; Risberg, May Arna

    2013-01-01

    Background The wish to return to level I pivoting sports is a major indication of ACL-reconstruction. Patients usually return to pivoting sports between 6 months and 1 year postoperatively, but no matched study has so far examined 1-year return to sport rates in nonoperatively and operatively treated ACL-injured patients. Hypothesis ACL-injured patients following a nonoperative treatment course, including recommendation of activity modification, will have lower return to pivoting sport rates than operatively treated patients 1 year after baseline testing/surgery, when matched by preinjury sports activity, age and sex. Study Design Pair-matched cohort study Methods Sixty-nine nonoperatively treated ACL-injured patients were pair-matched with 69 operatively treated patients (n=138), based on specific preinjury sport, age and sex. Nonoperatively treated patients were recommended not to return to level I sports. Patients were defined as nonoperatively or operatively treated according to their status at follow-up. The baseline and follow-up testing included registration of sports participation, KT-1000 measurements, 4 hop tests, and patient-reported outcome measures. McNemar’s test and paired t-tests or Wilcoxon’s test were used to compare outcomes of nonoperatively and operatively treated patients. Results No significant baseline differences were found. At 12.9±1.2 months (mean ± standard deviation) after baseline testing (nonoperative) and 12.7±1.2 months after surgery (operative), there was no significant difference in overall return to sport rates (nonoperative: 68.1 %, operative: 68.1 %, p=1.000), or in return to level I sport rates (nonoperative: 54.8 %, operative: 61.9 %, p=0.664). Nonoperatively treated patients who participated in level I sports prior to injury had a significantly lower return to sport rate (54.8 %) than nonoperatively treated patients who participated in level II sports (88.9 %, p=0.003). The nonoperatively treated patients had

  13. Sex in a test tube: testing the benefits of in vitro recombination.

    Science.gov (United States)

    Pesce, Diego; Lehman, Niles; de Visser, J Arjan G M

    2016-10-19

    The origin and evolution of sex, and the associated role of recombination, present a major problem in biology. Sex typically involves recombination of closely related DNA or RNA sequences, which is fundamentally a random process that creates but also breaks up beneficial allele combinations. Directed evolution experiments, which combine in vitro mutation and recombination protocols with in vitro or in vivo selection, have proved to be an effective approach for improving functionality of nucleic acids and enzymes. As this approach allows extreme control over evolutionary conditions and parameters, it also facilitates the detection of small or position-specific recombination benefits and benefits associated with recombination between highly divergent genotypes. Yet, in vitro approaches have been largely exploratory and motivated by obtaining improved end products rather than testing hypotheses of recombination benefits. Here, we review the various experimental systems and approaches used by in vitro studies of recombination, discuss what they say about the evolutionary role of recombination, and sketch their potential for addressing extant questions about the evolutionary role of sex and recombination, in particular on complex fitness landscapes. We also review recent insights into the role of 'extracellular recombination' during the origin of life.This article is part of the themed issue 'Weird sex: the underappreciated diversity of sexual reproduction'. © 2016 The Author(s).

  14. Biological sex affects the neurobiology of autism

    Science.gov (United States)

    Lombardo, Michael V.; Suckling, John; Ruigrok, Amber N. V.; Chakrabarti, Bhismadev; Ecker, Christine; Deoni, Sean C. L.; Craig, Michael C.; Murphy, Declan G. M.; Bullmore, Edward T.; Baron-Cohen, Simon

    2013-01-01

    In autism, heterogeneity is the rule rather than the exception. One obvious source of heterogeneity is biological sex. Since autism was first recognized, males with autism have disproportionately skewed research. Females with autism have thus been relatively overlooked, and have generally been assumed to have the same underlying neurobiology as males with autism. Growing evidence, however, suggests that this is an oversimplification that risks obscuring the biological base of autism. This study seeks to answer two questions about how autism is modulated by biological sex at the level of the brain: (i) is the neuroanatomy of autism different in males and females? and (ii) does the neuroanatomy of autism fit predictions from the ‘extreme male brain’ theory of autism, in males and/or in females? Neuroanatomical features derived from voxel-based morphometry were compared in a sample of equal-sized high-functioning male and female adults with and without autism (n = 120, n = 30/group). The first question was investigated using a 2 × 2 factorial design, and by spatial overlap analyses of the neuroanatomy of autism in males and females. The second question was tested through spatial overlap analyses of specific patterns predicted by the extreme male brain theory. We found that the neuroanatomy of autism differed between adult males and females, evidenced by minimal spatial overlap (not different from that occurred under random condition) in both grey and white matter, and substantially large white matter regions showing significant sex × diagnosis interactions in the 2 × 2 factorial design. These suggest that autism manifests differently by biological sex. Furthermore, atypical brain areas in females with autism substantially and non-randomly (P males with autism. How differences in neuroanatomy relate to the similarities in cognition between males and females with autism remains to be understood. Future research should stratify by biological sex to reduce

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

    Science.gov (United States)

    Blackmon, Heath; Ross, Laura; Bachtrog, Doris

    2017-01-01

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

  16. Anthropometric, cardiovascular and functional variables as indicators of health related physical fitness in university professors

    Directory of Open Access Journals (Sweden)

    Osvaldo Costa Moreira

    Full Text Available AbstractObjective To verify the behavior of anthropometric, cardiovascular and functional variables as indicators of health-related physical fitness in university professors and perform a comparison of these variables between sexes.Materials and methods We conducted an observational epidemiological cross-sectional study in 145 professors (45.86 ± 9.7 years, 103 men (71.03%, which were evaluated by measuring heart rate (HR and systolic (SBP and diastolic (DBP pressure at rest, body weight, height, body mass index (BMI, body fat percentage (BF%, handgrip strength (HGS, flexibility and cardiorespiratory fitness (CRF. We proceeded to the descriptive analysis, Student t-test for comparison between sexes and multiple regression analysis to verify the association between the variables analyzed. It was adopted a significance level of p < 0.05.Results The sex affected all variables. Women had better levels of BMI, flexibility, SBP and DBP. The BF% and CRF were associated with SBP and BMI in both sexes.Conclusion The behavior of anthropometric, cardiovascular and functional variables indicated unsatisfactory values for flexibility, HGS and BMI, with the worst levels among men. Furthermore, the variables that showed better association with HRPF were BF% and CRF.

  17. Caste-Specific and Sex-Specific Expression of Chemoreceptor Genes in a Termite.

    Directory of Open Access Journals (Sweden)

    Yuki Mitaka

    Full Text Available The sophisticated colony organization of eusocial insects is primarily maintained through the utilization of pheromones. The regulation of these complex social interactions requires intricate chemoreception systems. The recent publication of the genome of Zootermopsis nevadensis opened a new avenue to study molecular basis of termite caste systems. Although there has been a growing interest in the termite chemoreception system that regulates their sophisticated caste system, the relationship between division of labor and expression of chemoreceptor genes remains to be explored. Using high-throughput mRNA sequencing (RNA-seq, we found several chemoreceptors that are differentially expressed among castes and between sexes in a subterranean termite Reticulitermes speratus. In total, 53 chemoreception-related genes were annotated, including 22 odorant receptors, 7 gustatory receptors, 12 ionotropic receptors, 9 odorant-binding proteins, and 3 chemosensory proteins. Most of the chemoreception-related genes had caste-related and sex-related expression patterns; in particular, some chemoreception genes showed king-biased or queen-biased expression patterns. Moreover, more than half of the genes showed significant age-dependent differences in their expression in female and/or male reproductives. These results reveal a strong relationship between the evolution of the division of labor and the regulation of chemoreceptor gene expression, thereby demonstrating the chemical communication and underlining chemoreception mechanism in social insects.

  18. Exposure to 4100K fluorescent light elicits sex specific transcriptional responses in Xiphophorus maculatus skin.

    Science.gov (United States)

    Boswell, William T; Boswell, Mikki; Walter, Dylan J; Navarro, Kaela L; Chang, Jordan; Lu, Yuan; Savage, Markita G; Shen, Jianjun; Walter, Ronald B

    2018-06-01

    It has been reported that exposure to artificial light may affect oxygen intake, heart rate, absorption of vitamins and minerals, and behavioral responses in humans. We have reported specific gene expression responses in the skin of Xiphophorus fish after exposure to ultraviolet light (UV), as well as, both broad spectrum and narrow waveband visible light. In regard to fluorescent light (FL), we have shown that male X. maculatus exposed to 4100K FL (i.e. "cool white") rapidly suppress transcription of many genes involved with DNA replication and repair, chromosomal segregation, and cell cycle progression in skin. We have also detailed sex specific transcriptional responses of Xiphophorus skin after exposure to UVB. However, investigation of gender differences in global gene expression response after exposure to 4100K FL has not been reported, despite common use of this FL source for residential, commercial, and animal facility illumination. Here, we compare RNA-Seq results analyzed to assess changes in the global transcription profiles of female and male X. maculatus skin in response to 4100K FL exposure. Our results suggest 4100K FL exposure incites a sex-biased genetic response including up-modulation of inflammation in females and down modulation of DNA repair/replication in males. In addition, we identify clusters of genes that become oppositely modulated in males and females after FL exposure that are principally involved in cell death and cell proliferation. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Technology, normalisation and male sex work.

    Science.gov (United States)

    MacPhail, Catherine; Scott, John; Minichiello, Victor

    2015-01-01

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

  20. Intergranular attack evaluation from hideout return

    International Nuclear Information System (INIS)

    Nordmann, F.; Dupin, M.; Menet, O.; Fiquet, J.-M.

    1989-01-01

    Intergranular Attack (IGA) is the secondary side corrosion mechanism on PWR steam generator tubing, which can occur most frequently even with a good waterchemistry. It has moderately developed in a few French units. Consequently, several remedies have been implemented, such as sodium content decrease in makeup water and application of more stringent chemistry specifications. In order to evaluate the local chemistry in restricted areas where IGA may occur, a large hideout return programme has been carried out on many units. It shows that free alkalinity returning during shutdown is usually ranging from 0.5 to 5 g of sodium per steam generator, and that the required time to let it return is about 40 hours. However, high temperature pH calculations indicate that such an amount of alkalinity can correspond to a potentially corrosive solution in restricted areas, where a concentration factor of 10 5 to 10 7 can be reached, inducing a pH of 10 at 300 o C. Studies are still in progress in order to define when a shutdown should be required to allow hideout return and help to prevent IGA. (author)

  1. Gene co-expression networks in liver and muscle transcriptome reveal sex-specific gene expression in lambs fed with a mix of essential oils

    DEFF Research Database (Denmark)

    Sabino, Marcella; Carmelo, Victor Adriano Okstoft; Mazzoni, Gianluca

    2018-01-01

    the potential of RNA-Sequencing data in order to evaluate the effect of an EO supplementary diet on gene expression in both lamb liver and muscle. Using a treatment and sex interaction model, 13 and 4 differentially expressed genes were identified in liver and muscle respectively. Sex-specific differentially...... on the expression profile of both liver and muscle tissues. We hypothesize that the presence of EOs could have beneficial effects on wellness of male lamb and further analyses are needed to understand the biological mechanisms behind the different effect of EO metabolites based on sex. Using lamb as a model...

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

    Science.gov (United States)

    Frynta, Daniel; Vejvodová, Tereza; Šimková, Olga

    2016-06-01

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

  3. Maternal obesity and sex-specific differences in placental pathology.

    Science.gov (United States)

    Leon-Garcia, Sandra M; Roeder, Hilary A; Nelson, Katharine K; Liao, Xiaoyan; Pizzo, Donald P; Laurent, Louise C; Parast, Mana M; LaCoursiere, D Yvette

    2016-02-01

    Adverse effects of obesity have been linked to inflammation in various tissues, but studies on placental inflammation and obesity have demonstrated conflicting findings. We sought to investigate the influence of pregravid obesity and fetal sex on placental histopathology while controlling for diabetes and hypertension. Placental histopathology focusing on inflammatory markers of a cohort of normal weight (BMI = 20-24.9) and obese (BMI ≥ 30) patients was characterized. Demographic, obstetric and neonatal variables were assessed. 192 normal and 231 obese women were included. Placental characteristics associated with obesity and fetal sex independent of diabetes and hypertension were placental disc weight >90(th) percentile, decreased placental efficiency, chronic villitis (CV), fetal thrombosis, and normoblastemia. Additionally, female fetuses of obese mothers had higher rates of CV and fetal thrombosis. Increasing BMI increased the risk of normoblastemia and CV. The final grade and extent of CV was significantly associated with obesity and BMI, but not fetal gender. Finally, CV was less common in large-for-gestation placentas. Maternal obesity results in placental overgrowth and fetal hypoxia as manifested by normoblastemia; it is also associated with an increased incidence of CV and fetal thrombosis, both more prevalent in female placentas. We have shown for the first time that the effect of maternal obesity on placental inflammation is independent of diabetes and hypertension, but significantly affected by fetal sex. Our data also point to the intriguing possibility that CV serves to normalize placental size, and potentially fetal growth, in the setting of maternal obesity. Copyright © 2015. Published by Elsevier Ltd.

  4. Latent class analysis of substance use among men who have sex with men in Malaysia: Findings from the Asian Internet MSM Sex Survey.

    Science.gov (United States)

    Lim, Sin How; Cheung, Doug H; Guadamuz, Thomas E; Wei, Chongyi; Koe, Stuart; Altice, Frederick L

    2015-06-01

    High prevalence of substance use among men who have sex with men (MSM) may drive the HIV epidemic in Malaysia but patterns of substance use among Malaysian MSM have not been examined. Our study investigated specific Malaysian MSM risk groups to determine the association between their substance use and sexual risk behaviors. Data from Malaysian respondents (n=1235) in a large, multinational online survey of Asian MSM in 2010 were used to identify latent classes of substance use. Subsequent covariates were included in a joint model to predict class membership. The 3-class model was identified as the best fitting model, which included: (1) 'negligible substance use' for those reporting none or using any substance sparingly; (2) 'soft substance use' for those using poppers, ecstasy and drinking before sex; and (3) 'amphetamine-type stimulant (ATS) use' for those using stimulants (methamphetamine, ecstasy), erectile dysfunction drugs and recreational drug use before sex. Men in the 'ATS use' category were significantly less likely to not know their HIV status (AOR: 0.30, 95%CI: 0.14,0.66), more likely to have had more than 6 male sex partners (AOR: 4.83, 95% CI: 1.92-12.2), to have group sex (AOR:4.07, 95% CI: 2.31-7.15), to report inconsistent condom use (AOR:2.01, 95% CI: 1.12-3.60), to be HIV-infected (AOR:3.92, 95% CI: 1.63-8.42) and to have had any sexually transmitted infections (AOR:3.92, 95% CI:1.70, 9.08), compared to men in the 'negligible substance use' category. Our study identified subgroups of Malaysian MSM with distinct substance use patterns and HIV-related risk profiles, which provides implication for targeting HIV prevention in this subpopulation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  5. Sex-specific consequences of an induced immune response on reproduction in a moth.

    Science.gov (United States)

    Barthel, Andrea; Staudacher, Heike; Schmaltz, Antje; Heckel, David G; Groot, Astrid T

    2015-12-16

    Immune response induction benefits insects in combatting infection by pathogens. However, organisms have a limited amount of resources available and face the dilemma of partitioning resources between immunity and other life-history traits. Since males and females differ in their life histories, sex-specific resource investment strategies to achieve an optimal immune response following an infection can be expected. We investigated immune response induction of females and males of Heliothis virescens in response to the entomopathogenic bacterium Serratia entomophila, and its effects on mating success and the female sexual signal. We found that females had higher expression levels of immune-related genes after bacterial challenge than males. However, males maintained a higher baseline expression of immune-related genes than females. The increased investment in immunity of female moths was negatively correlated with mating success and the female sexual signal. Male mating success was unaffected by bacterial challenge. Our results show that the sexes differed in their investment strategies: females invested in immune defense after a bacterial challenge, indicating facultative immune deployment, whereas males had higher baseline immunity than females, indicating immune maintenance. Interestingly, these differences in investment were reflected in the mate choice assays. As female moths are the sexual signallers, females need to invest resources in their attractiveness. However, female moths appeared to invest in immunity at the cost of reproductive effort.

  6. Return emigration: analysis of the situation through life stories

    Directory of Open Access Journals (Sweden)

    M.R Pino Juste

    2014-11-01

    Full Text Available In the context of the importance presently acquired by return immigration in Spain, in this article a descriptive study around the returned emigrants over 65 years old in Galicia is presented.After a brief theoretical introduction on return migration,the research carried out is developed. In the first place, the methodology used in the investigation which allowed an approach to the point of view of the persons concerned is explained: the biographical method through the technique of life stories. In second term, the specific results of the research are presented. After out lining the profile of the returned emigrant, different categories relating to the migratory project in its different phases have been analyzed: fromits beginning —reasons for emigrating—, in their arrival to destiny—labour activity, adaptation, uprooting, etc.—, to the return—reasons for returning, problems of readjustment to the place of origin, etc.—

  7. The maintenance of sex: Ronald Fisher meets the Red Queen.

    Science.gov (United States)

    Green, David; Mason, Chris

    2013-08-21

    Sex in higher diploids carries a two-fold cost of males that should reduce its fitness relative to cloning, and result in its extinction. Instead, sex is widespread and clonal species face early obsolescence. One possible reason is that sex is an adaptation that allows organisms to respond more effectively to endless changes in their environment. The purpose of this study was to model mutation and selection in a diploid organism in an evolving environment and ascertain their support for sex. We used a computational approach to model finite populations where a haploid environment subjects a diploid host to endlessly evolving change. Evolution in both populations is primarily through adoption of novel advantageous mutations within a large allele space. Sex outcompetes cloning by two complementary mechanisms. First, sexual diploids adopt advantageous homozygous mutations more rapidly than clonal ones under conditions of lag load (the gap between the actual adaptation of the diploid population and its theoretical optimum). This rate advantage can offset the higher fecundity of cloning. Second, a relative advantage to sex emerges where populations are significantly polymorphic, because clonal polymorphism runs the risk of clonal interference caused by selection on numerous lines of similar adaptation. This interference extends allele lifetime and reduces the rate of adaptation. Sex abolishes the interference, making selection faster and elevating population fitness. Differences in adaptation between sexual and clonal populations increase markedly with the number of loci under selection, the rate of mutation in the host, and a rapidly evolving environment. Clonal interference in these circumstances leads to conditions where the greater fecundity of clones is unable to offset their poor adaptation. Sexual and clonal populations then either co-exist, or sex emerges as the more stable evolutionary strategy. Sex can out-compete clones in a rapidly evolving environment, such

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

    Science.gov (United States)

    Fritzsche, Karoline; Booksmythe, Isobel; Arnqvist, Göran

    2016-09-26

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

  9. Genetics of dioecy and causal sex chromosomes in plants

    Indian Academy of Sciences (India)

    2014-04-15

    chromosome evolution; sex-ratio variation ...... interaction between the two genes, Cm ACS7 and Cm W1P1, ... son of low pollinator density seed formation will be scanty ...... Kaltz O. and Bell G. 2002 The ecology and genetics of fitness in.

  10. Sex-specific effects of prenatal and postnatal nutritional conditions on the oxidative status of great tit nestlings.

    Science.gov (United States)

    Giordano, M; Costantini, D; Tschirren, B

    2015-01-01

    The early life period is characterized by fast growth and development, which can lead to high reactive oxygen species (ROS) production. Young animals thus have to balance their investment in growth versus ROS defence, and this balance is likely mediated by resource availability. Consequently resources transferred prenatally by the mother and nutritional conditions experienced shortly after birth may crucially determine the oxidative status of young animals. Here, we experimentally investigated the relative importance of pre- and early postnatal nutritional conditions on the oxidative status of great tit nestlings (Parus major). We show that resources transferred by the mother through the egg and nutritional conditions encountered after hatching affect the oxidative status of nestling in a sex-specific way. Daughters of non-supplemented mothers and daughters which did not receive extra food during the early postnatal period had higher oxidative damage than sons, while no differences between sons and daughters were found when extra food was provided pre- or postnatally. No effect of the food supplementations on growth, fledging mass or tarsus length was observed, indicating that female nestlings maintained their investment in growth at the expense of ROS defence mechanisms when resources were limited. The lower priority of the antioxidant defence system for female nestlings was also evidenced by lower levels of specific antioxidant components. These results highlight the important role of early parental effects in shaping oxidative stress in the offspring, and show that the sensitivity to these parental effects is sex-specific.

  11. [Factors associated with low levels of aerobic fitness among adolescents].

    Science.gov (United States)

    Gonçalves, Eliane Cristina de Andrade; Silva, Diego Augusto Santos

    2016-06-01

    To evaluate the prevalence of low aerobic fitness levels and to analyze the association with sociodemographic factors, lifestyle and excess body fatness among adolescents of southern Brazil. The study included 879 adolescents aged 14 to 19 years the city of São José/SC, Brazil. The aerobic fitness was assessed by Canadian modified test of aerobic fitness. Sociodemographic variables (skin color, age, sex, study turn, economic level), sexual maturation and lifestyle (eating habits, screen time, physical activity, consumption of alcohol and tobacco) were assessed by a self-administered questionnaire. Excess body fatness was evaluated by sum of skinfolds triceps and subscapular. We used logistic regression to estimate odds ratios and 95% confidence intervals. Prevalence of low aerobic fitness level was 87.5%. The girls who spent two hours or more in front screen, consumed less than one glass of milk by day, did not smoke and had an excess of body fatness had a higher chance of having lower levels of aerobic fitness. White boys with low physical activity had had a higher chance of having lower levels of aerobic fitness. Eight out of ten adolescents were with low fitness levels aerobic. Modifiable lifestyle factors were associated with low levels of aerobic fitness. Interventions that emphasize behavior change are needed. Copyright © 2015 Sociedade de Pediatria de São Paulo. Publicado por Elsevier Editora Ltda. All rights reserved.

  12. Pre-Tenured Faculty Job Satisfaction: An Examination of Personal Fit, Institutional Fit and Faculty Work-Life

    Science.gov (United States)

    Awando, Maxwell

    2014-01-01

    The purpose of this study is to explore job satisfaction among pre-tenured faculty. More specifically I was interested in examining demographic and personal fit factors, fit with the norms and values of the institution among pre-tenured faculty in different institutional types. The sample for the study included all pre-tenured faculty members who…

  13. Margin Requirements and Equity Option Returns

    DEFF Research Database (Denmark)

    Hitzemann, Steffen; Hofmann, Michael; Uhrig-Homburg, Marliese

    In equity option markets, traders face margin requirements both for the options themselves and for hedging-related positions in the underlying stock market. We show that these requirements carry a significant margin premium in the cross-section of equity option returns. The sign of the margin...... premium depends on demand pressure: If end-users are on the long side of the market, option returns decrease with margins, while they increase otherwise. Our results are statistically and economically significant and robust to different margin specifications and various control variables. We explain our...... findings by a model of funding-constrained derivatives dealers that require compensation for satisfying end-users’ option demand....

  14. Margin Requirements and Equity Option Returns

    DEFF Research Database (Denmark)

    Hitzemann, Steffen; Hofmann, Michael; Uhrig-Homburg, Marliese

    In equity option markets, traders face margin requirements both for the options themselves and for hedging-related positions in the underlying stock market. We show that these requirements carry a significant "margin premium" in the cross-section of equity option returns. The sign of the margin...... premium depends on demand pressure: If end-users are on the long side of the market, option returns decrease with margins, while they increase otherwise. Our results are statistically and economically significant and robust to different margin specifications and various control variables. We explain our...... findings by a model of funding-constrained derivatives dealers that require compensation for satisfying end-users’ option demand....

  15. In-hospital Breastfeeding and Intention to Return to Work Influence Mothers' Breastfeeding Intentions.

    Science.gov (United States)

    Thomas-Jackson, Shera C; Bentley, Gail E; Keyton, Kristina; Reifman, Alan; Boylan, Mallory; Hart, Sybil L

    2016-11-01

    Research continues to demonstrate that formula feeding is associated with numerous long-term negative outcomes for a mother and her infant. However, many women cease breastfeeding sooner than intended and recommended. Breastfeeding has been found to be related to demographics, maternal mood, and returning to work outside the home. This study aimed to shed light on the woman's perception of the effect of working on intended breastfeeding duration. This study used intentions to return to work and in-hospital breastfeeding to predict breastfeeding intentions. Women (N = 160) were surveyed during the first 48 hours postdelivery of healthy, full-term infants. Survey instruments included demographics (socioeconomic status, maternal age, education, and marital status), depression, fetal attachment, current exclusive breastfeeding status, as well as breastfeeding and return-to-work intentions for the next year. A path analysis was used to explore relationships and predictors of breastfeeding intentions. The model had a good fit and breastfeeding intentions were predicted by exclusive breastfeeding in the hospital (β = 0.21, P work (β = -0.18, P work influence how long a mother intends to breastfeed. Attention to these areas can be provided immediately postpartum to support exclusive breastfeeding and provide informational support on continuing to breastfeed/express milk upon return to work if the mother intends to return to work.

  16. How fit are children and adolescents with haemophilia in Germany? Results of a prospective study assessing the sport-specific motor performance by means of modern test procedures of sports science.

    Science.gov (United States)

    Seuser, A; Boehm, P; Ochs, S; Trunz-Carlisi, E; Halimeh, S; Klamroth, R

    2015-07-01

    There are a lot of publications on the physical fitness of patients with haemophilia (PWH), however, most studies only reflect individual sport-specific motor capacities or focus on a single fitness ability. They involve small patient populations. In this respect principal objective of this study was to compare the physical fitness in all respects and the body composition of young PWH to healthy peers based on the most valid data we could get. Twenty-one German haemophilia treatment centres were visited from 2002 to 2009. PWH between 8 and 25 years were included. They performed a five-stage fitness test covering the sport-specific motor capacities for coordination, measured by one leg stand, strength, aerobic fitness and mobility as well as body composition. The patients' results were compared with age- and gender-specific reference values of healthy subjects. Two hundred and eighty-five PWH (mean age 13.2 ± 4.5 years, 164 PWH with severe disease) were included prospectively in the study. PWH are significantly below the reference values of healthy subjects in the one-leg stand test, the mobility of the lower extremity, the strength ratio of chest and back muscles and the endurance test. In body composition, the back strength and the mobility of the upper extremity PWH are significantly above the reference values. There are no significant differences in abdominal strength. In conclusion we found specific differences in different fitness abilities between PWH and healthy subjects. Knowing this, we are able to work out exercise programmes to compensate the diminished fitness abilities for our PWH. © 2015 John Wiley & Sons Ltd.

  17. Mutations in the testis-specific enhancer of SOX9 in the SRY independent sex-determining mechanism in the genus Tokudaia.

    Directory of Open Access Journals (Sweden)

    Ryutaro Kimura

    Full Text Available SRY (sex-determining region Y is widely conserved in eutherian mammals as a sex-determining gene located on the Y chromosome. SRY proteins bind to the testis-specific enhancer of SOX9 (TES with SF1 to upregulate SOX9 expression in undifferentiated gonads of XY embryos of humans and mice. The core region within TES, named TESCO, is an important enhancer for mammalian sex determination. We show that TESCO of the genus Tokudaia lost enhancer activity caused by mutations in its SRY and SF1 binding sites. Two species of Tokudaia do not have the Y chromosome or SRY, and one species has multiple SRYs located on the neo-Y chromosome consisting of the Y fused with an autosome. The sequence of Tokudaia TESCO exhibited more than 83% identity with mouse TESCO, however, nucleotide substitution(s were found in two out of three SRY binding sites and in five out of six SF1 binding sites. TESCO of all species showed low enhancer activity in cells co-transfected with SRY and SF1, and SOX9 and SF1 in reporter gene assays. Mutated TESCO, in which nucleotide substitutions found in SRY and SF1 binding sites were replaced with mouse sequence, recovered the activity. Furthermore, SRYs of the SRY-positive species could not activate the mutated TESCO or mouse TESCO, suggesting that SRYs lost function as a sex-determining gene any more. Our results indicate that the SRY dependent sex-determining mechanism was lost in a common ancestor of the genus Tokudaia caused by nucleotide substitutions in SRY and SF1 binding sites after emergence of a new sex-determining gene. We present the first evidence for an intermediate stage of the switchover from SRY to a new sex-determining gene in the evolution of mammalian sex-determining mechanism.

  18. Mutations in the testis-specific enhancer of SOX9 in the SRY independent sex-determining mechanism in the genus Tokudaia.

    Science.gov (United States)

    Kimura, Ryutaro; Murata, Chie; Kuroki, Yoko; Kuroiwa, Asato

    2014-01-01

    SRY (sex-determining region Y) is widely conserved in eutherian mammals as a sex-determining gene located on the Y chromosome. SRY proteins bind to the testis-specific enhancer of SOX9 (TES) with SF1 to upregulate SOX9 expression in undifferentiated gonads of XY embryos of humans and mice. The core region within TES, named TESCO, is an important enhancer for mammalian sex determination. We show that TESCO of the genus Tokudaia lost enhancer activity caused by mutations in its SRY and SF1 binding sites. Two species of Tokudaia do not have the Y chromosome or SRY, and one species has multiple SRYs located on the neo-Y chromosome consisting of the Y fused with an autosome. The sequence of Tokudaia TESCO exhibited more than 83% identity with mouse TESCO, however, nucleotide substitution(s) were found in two out of three SRY binding sites and in five out of six SF1 binding sites. TESCO of all species showed low enhancer activity in cells co-transfected with SRY and SF1, and SOX9 and SF1 in reporter gene assays. Mutated TESCO, in which nucleotide substitutions found in SRY and SF1 binding sites were replaced with mouse sequence, recovered the activity. Furthermore, SRYs of the SRY-positive species could not activate the mutated TESCO or mouse TESCO, suggesting that SRYs lost function as a sex-determining gene any more. Our results indicate that the SRY dependent sex-determining mechanism was lost in a common ancestor of the genus Tokudaia caused by nucleotide substitutions in SRY and SF1 binding sites after emergence of a new sex-determining gene. We present the first evidence for an intermediate stage of the switchover from SRY to a new sex-determining gene in the evolution of mammalian sex-determining mechanism.

  19. Sex allocation theory reveals a hidden cost of neonicotinoid exposure in a parasitoid wasp.

    Science.gov (United States)

    Whitehorn, Penelope R; Cook, Nicola; Blackburn, Charlotte V; Gill, Sophie M; Green, Jade; Shuker, David M

    2015-05-22

    Sex allocation theory has proved to be one the most successful theories in evolutionary ecology. However, its role in more applied aspects of ecology has been limited. Here we show how sex allocation theory helps uncover an otherwise hidden cost of neonicotinoid exposure in the parasitoid wasp Nasonia vitripennis. Female N. vitripennis allocate the sex of their offspring in line with Local Mate Competition (LMC) theory. Neonicotinoids are an economically important class of insecticides, but their deployment remains controversial, with evidence linking them to the decline of beneficial species. We demonstrate for the first time to our knowledge, that neonicotinoids disrupt the crucial reproductive behaviour of facultative sex allocation at sub-lethal, field-relevant doses in N. vitripennis. The quantitative predictions we can make from LMC theory show that females exposed to neonicotinoids are less able to allocate sex optimally and that this failure imposes a significant fitness cost. Our work highlights that understanding the ecological consequences of neonicotinoid deployment requires not just measures of mortality or even fecundity reduction among non-target species, but also measures that capture broader fitness costs, in this case offspring sex allocation. Our work also highlights new avenues for exploring how females obtain information when allocating sex under LMC. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  20. Sex- and habitat-specific movement of an omnivorous semi-terrestrial crab controls habitat connectivity and subsidies: a multi-parameter approach.

    Science.gov (United States)

    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

  1. Sex-specific interactions between the IRS1 polymorphism and intakes of carbohydrates and fat on incident type 2 diabetes.

    Science.gov (United States)

    Ericson, Ulrika; Rukh, Gull; Stojkovic, Ivana; Sonestedt, Emily; Gullberg, Bo; Wirfält, Elisabet; Wallström, Peter; Orho-Melander, Marju

    2013-01-01

    The minor T allele of rs2943641 near the gene encoding for insulin receptor substrate 1 (IRS1) has been associated with decreased risk of type 2 diabetes (T2D) and adiposity in genome-wide association studies. Dietary intake can influence the regulation of IRS1, and studies have indicated sex-specific associations between IRS1 and adiposity. The objective was to examine the interaction between IRS1 rs2943641 and macronutrient intakes on incident T2D and percentage body fat in the Malmö Diet and Cancer cohort. The study included 15,227 women and 9614 men aged 45-74 y without prevalent diabetes. Dietary data were collected with a modified diet history method. During 12 y of follow-up, 1567 incident T2D cases were identified. The T allele was associated with lower incidence of T2D (P-trend = 0.003) and, in men, with higher percentage body fat (P-trend = 0.00002). We observed 3-way interactions between sex, rs2943641, and carbohydrate intake (P = 0.01) as well as between sex, rs2943641, and fat intake (P = 0.01) on incident T2D. Among women, the T allele was associated with decreased risk only in the lower tertiles of carbohydrate intake (P-trend = 0.01, P-interaction = 0.01). In contrast, among men, the T allele was associated with decreased risk in the lowest tertile of fat intake (P-trend = 0.01, P-interaction = 0.02). No interaction was observed between macronutrient intakes and rs2943641 on percentage body fat. Our results indicate that IRS1 rs2943641 interacts with carbohydrate and fat intakes on incident T2D in a sex-specific fashion. A protective association between the rs2943641 T allele and T2D was restricted to women with low carbohydrate intake and to men with low fat intake.

  2. Inter-Annual Variability of Fledgling Sex Ratio in King Penguins.

    Directory of Open Access Journals (Sweden)

    Célia Bordier

    Full Text Available As the number of breeding pairs depends on the adult sex ratio in a monogamous species with biparental care, investigating sex-ratio variability in natural populations is essential to understand population dynamics. Using 10 years of data (2000-2009 in a seasonally monogamous seabird, the king penguin (Aptenodytes patagonicus, we investigated the annual sex ratio at fledging, and the potential environmental causes for its variation. Over more than 4000 birds, the annual sex ratio at fledging was highly variable (ranging from 44.4% to 58.3% of males, and on average slightly biased towards males (51.6%. Yearly variation in sex-ratio bias was neither related to density within the colony, nor to global or local oceanographic conditions known to affect both the productivity and accessibility of penguin foraging areas. However, rising sea surface temperature coincided with an increase in fledging sex-ratio variability. Fledging sex ratio was also correlated with difference in body condition between male and female fledglings. When more males were produced in a given year, their body condition was higher (and reciprocally, suggesting that parents might adopt a sex-biased allocation strategy depending on yearly environmental conditions and/or that the effect of environmental parameters on chick condition and survival may be sex-dependent. The initial bias in sex ratio observed at the juvenile stage tended to return to 1∶1 equilibrium upon first breeding attempts, as would be expected from Fisher's classic theory of offspring sex-ratio variation.

  3. Inter-Annual Variability of Fledgling Sex Ratio in King Penguins.

    Science.gov (United States)

    Bordier, Célia; Saraux, Claire; Viblanc, Vincent A; Gachot-Neveu, Hélène; Beaugey, Magali; Le Maho, Yvon; Le Bohec, Céline

    2014-01-01

    As the number of breeding pairs depends on the adult sex ratio in a monogamous species with biparental care, investigating sex-ratio variability in natural populations is essential to understand population dynamics. Using 10 years of data (2000-2009) in a seasonally monogamous seabird, the king penguin (Aptenodytes patagonicus), we investigated the annual sex ratio at fledging, and the potential environmental causes for its variation. Over more than 4000 birds, the annual sex ratio at fledging was highly variable (ranging from 44.4% to 58.3% of males), and on average slightly biased towards males (51.6%). Yearly variation in sex-ratio bias was neither related to density within the colony, nor to global or local oceanographic conditions known to affect both the productivity and accessibility of penguin foraging areas. However, rising sea surface temperature coincided with an increase in fledging sex-ratio variability. Fledging sex ratio was also correlated with difference in body condition between male and female fledglings. When more males were produced in a given year, their body condition was higher (and reciprocally), suggesting that parents might adopt a sex-biased allocation strategy depending on yearly environmental conditions and/or that the effect of environmental parameters on chick condition and survival may be sex-dependent. The initial bias in sex ratio observed at the juvenile stage tended to return to 1∶1 equilibrium upon first breeding attempts, as would be expected from Fisher's classic theory of offspring sex-ratio variation.

  4. The sex specific metabolic footprint of Oithona davisae

    DEFF Research Database (Denmark)

    Heuschele, Jan; Nemming, Louise; Tolstrup, Lea

    2016-01-01

    and behaviour in several phytoplankton species. Here we tested whether the sexual dimorphism in morphology and behaviour is mirrored in the exudate composition of males and females. We find differences in the exudate composition, with females seemingly producing more compounds. While we were able to remove...... the sex pheromones from the water by filtration through reverse phase solid phase extraction columns, we were not able to recover the active pheromone from the solid phase....

  5. Explaining sex differences in lifespan in terms of optimal energy allocation in the baboon.

    Science.gov (United States)

    King, Annette M; Kirkwood, Thomas B L; Shanley, Daryl P

    2017-10-01

    We provide a quantitative test of the hypothesis that sex role specialization may account for sex differences in lifespan in baboons if such specialization causes the dependency of fitness upon longevity, and consequently the optimal resolution to an energetic trade-off between somatic maintenance and other physiological functions, to differ between males and females. We present a model in which females provide all offspring care and males compete for access to reproductive females and in which the partitioning of available energy between the competing fitness-enhancing functions of growth, maintenance, and reproduction is modeled as a dynamic behavioral game, with the optimal decision for each individual depending upon his/her state and the behavior of other members of the population. Our model replicates the sexual dimorphism in body size and sex differences in longevity and reproductive scheduling seen in natural populations of baboons. We show that this outcome is generally robust to perturbations in model parameters, an important finding given that the same behavior is seen across multiple populations and species in the wild. This supports the idea that sex differences in longevity result from differences in the value of somatic maintenance relative to other fitness-enhancing functions in keeping with the disposable soma theory. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  6. Sex ratio at birth and mortality rates are negatively related in humans.

    Directory of Open Access Journals (Sweden)

    Madhukar Shivajirao Dama

    Full Text Available Evolutionary theory posits that resource availability and parental investment ability could signal offspring sex selection, in order to maximize reproductive returns. Non-human studies have provided evidence for this phenomenon, and maternal condition around the time of conception has been identified as most important factor that influence offspring sex selection. However, studies on humans have reported inconsistent results, mostly due to use of disparate measures as indicators of maternal condition. In the present study, the cross-cultural differences in human natal sex ratio were analyzed with respect to indirect measures of condition namely, life expectancy and mortality rate. Multiple regression modeling suggested that mortality rates have distinct predictive power independent of cross-cultural differences in fertility, wealth and latitude that were earlier shown to predict sex ratio at birth. These findings suggest that sex ratio variation in humans may relate to differences in parental and environmental conditions.

  7. Longevity enhances selection of environmental sex determination.

    Science.gov (United States)

    Bull, J J; Bulmer, M G

    1989-12-01

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

  8. Sex & vision I: Spatio-temporal resolution

    Directory of Open Access Journals (Sweden)

    Abramov Israel

    2012-09-01

    Full Text Available Abstract Background Cerebral cortex has a very large number of testosterone receptors, which could be a basis for sex differences in sensory functions. For example, audition has clear sex differences, which are related to serum testosterone levels. Of all major sensory systems only vision has not been examined for sex differences, which is surprising because occipital lobe (primary visual projection area may have the highest density of testosterone receptors in the cortex. We have examined a basic visual function: spatial and temporal pattern resolution and acuity. Methods We tested large groups of young adults with normal vision. They were screened with a battery of standard tests that examined acuity, color vision, and stereopsis. We sampled the visual system’s contrast-sensitivity function (CSF across the entire spatio-temporal space: 6 spatial frequencies at each of 5 temporal rates. Stimuli were gratings with sinusoidal luminance profiles generated on a special-purpose computer screen; their contrast was also sinusoidally modulated in time. We measured threshold contrasts using a criterion-free (forced-choice, adaptive psychophysical method (QUEST algorithm. Also, each individual’s acuity limit was estimated by fitting his or her data with a model and extrapolating to find the spatial frequency corresponding to 100% contrast. Results At a very low temporal rate, the spatial CSF was the canonical inverted-U; but for higher temporal rates, the maxima of the spatial CSFs shifted: Observers lost sensitivity at high spatial frequencies and gained sensitivity at low frequencies; also, all the maxima of the CSFs shifted by about the same amount in spatial frequency. Main effect: there was a significant (ANOVA sex difference. Across the entire spatio-temporal domain, males were more sensitive, especially at higher spatial frequencies; similarly males had significantly better acuity at all temporal rates. Conclusion As with other sensory systems

  9. Sex Hormones and Tendon

    DEFF Research Database (Denmark)

    Hansen, Mette; Kjaer, Michael

    2016-01-01

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

  10. Returns to schooling in the Portuguese economy: a reassessment

    Directory of Open Access Journals (Sweden)

    Maria Manuel Campos

    2018-06-01

    Full Text Available This paper provides an overview of the evolution of private returns to schooling in the Portuguese economy along the 1986-2013 period. We estimate the returns separately for men and women, at the mean and along the conditional wage distribution. Returns to schooling are found to be high, particularly for women, and to increase along the distribution. The magnitude of the returns increased throughout the 1986-2013 period, but particularly in the 1990s. We also provide estimates of the relative wage premium associated with specific levels of educational attainment and find that they are highest for tertiary education. In the first decades under analysis, relative wage premia associated with the 9th grade stand above those estimated for secondary education, whereas in the most recent period these differences are negligible.

  11. Cardiovascular biomarkers and sex: the case for women.

    Science.gov (United States)

    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.

  12. HIV Testing and Counseling Among Female Sex Workers : A Systematic Literature Review

    NARCIS (Netherlands)

    Tokar, Anna; Broerse, Jacqueline E.W.; Blanchard, James; Roura, Maria

    2018-01-01

    HIV testing uptake continues to be low among Female Sex Workers (FSWs). We synthesizes evidence on barriers and facilitators to HIV testing among FSW as well as frequencies of testing, willingness to test, and return rates to collect results. We systematically searched the MEDLINE/PubMed, EMBASE,

  13. Behavioral stress alters corticolimbic microglia in a sex- and brain region-specific manner.

    Science.gov (United States)

    Bollinger, Justin L; Collins, Kaitlyn E; Patel, Rushi; Wellman, Cara L

    2017-01-01

    Women are more susceptible to numerous stress-linked psychological disorders (e.g., depression) characterized by dysfunction of corticolimbic brain regions critical for emotion regulation and cognitive function. Although sparsely investigated, a number of studies indicate sex differences in stress effects on neuronal structure, function, and behaviors associated with these regions. We recently demonstrated a basal sex difference in- and differential effects of stress on- microglial activation in medial prefrontal cortex (mPFC). The resident immune cells of the brain, microglia are implicated in synaptic and dendritic plasticity, and cognitive-behavioral function. Here, we examined the effects of acute (3h/day, 1 day) and chronic (3h/day, 10 days) restraint stress on microglial density and morphology, as well as immune factor expression in orbitofrontal cortex (OFC), basolateral amygdala (BLA), and dorsal hippocampus (DHC) in male and female rats. Microglia were visualized, classified based on their morphology, and stereologically counted. Microglia-associated transcripts (CD40, iNOS, Arg1, CX3CL1, CX3CR1, CD200, and CD200R) were assessed in brain punches from each region. Expression of genes linked with cellular stress, neuroimmune state, and neuron-microglia communication varied between unstressed male and female rats in a region-specific manner. In OFC, chronic stress upregulated a wider variety of immune factors in females than in males. Acute stress increased microglia-associated transcripts in BLA in males, whereas chronic stress altered immune factor expression in BLA more broadly in females. In DHC, chronic stress increased immune factor expression in males but not females. Moreover, acute and chronic stress differentially affected microglial morphological activation state in male and female rats across all brain regions investigated. In males, chronic stress altered microglial activation in a pattern consistent with microglial involvement in stress

  14. Behavioral stress alters corticolimbic microglia in a sex- and brain region-specific manner

    Science.gov (United States)

    Bollinger, Justin L.; Collins, Kaitlyn E.; Patel, Rushi

    2017-01-01

    Women are more susceptible to numerous stress-linked psychological disorders (e.g., depression) characterized by dysfunction of corticolimbic brain regions critical for emotion regulation and cognitive function. Although sparsely investigated, a number of studies indicate sex differences in stress effects on neuronal structure, function, and behaviors associated with these regions. We recently demonstrated a basal sex difference in- and differential effects of stress on- microglial activation in medial prefrontal cortex (mPFC). The resident immune cells of the brain, microglia are implicated in synaptic and dendritic plasticity, and cognitive-behavioral function. Here, we examined the effects of acute (3h/day, 1 day) and chronic (3h/day, 10 days) restraint stress on microglial density and morphology, as well as immune factor expression in orbitofrontal cortex (OFC), basolateral amygdala (BLA), and dorsal hippocampus (DHC) in male and female rats. Microglia were visualized, classified based on their morphology, and stereologically counted. Microglia-associated transcripts (CD40, iNOS, Arg1, CX3CL1, CX3CR1, CD200, and CD200R) were assessed in brain punches from each region. Expression of genes linked with cellular stress, neuroimmune state, and neuron-microglia communication varied between unstressed male and female rats in a region-specific manner. In OFC, chronic stress upregulated a wider variety of immune factors in females than in males. Acute stress increased microglia-associated transcripts in BLA in males, whereas chronic stress altered immune factor expression in BLA more broadly in females. In DHC, chronic stress increased immune factor expression in males but not females. Moreover, acute and chronic stress differentially affected microglial morphological activation state in male and female rats across all brain regions investigated. In males, chronic stress altered microglial activation in a pattern consistent with microglial involvement in stress

  15. Associations of prodynorphin sequence variation with alcohol dependence and related traits are phenotype-specific and sex-dependent.

    Science.gov (United States)

    Winham, Stacey J; Preuss, Ulrich W; Geske, Jennifer R; Zill, Peter; Heit, John A; Bakalkin, Georgy; Biernacka, Joanna M; Karpyak, Victor M

    2015-10-27

    We previously demonstrated that prodynorphin (PDYN) haplotypes and single nucleotide polymorphism (SNP) rs2281285 are associated with alcohol dependence and the propensity to drink in negative emotional states, and recent studies suggest that PDYN gene effects on substance dependence risk may be sex-related. We examined sex-dependent associations of PDYN variation with alcohol dependence and related phenotypes, including negative craving, time until relapse after treatment and the length of sobriety episodes before seeking treatment, in discovery and validation cohorts of European ancestry. We found a significant haplotype-by-sex interaction (p  =  0.03), suggesting association with alcohol dependence in males (p = 1E-4) but not females. The rs2281285 G allele increased risk for alcohol dependence in males in the discovery cohort (OR = 1.49, p = 0.002), with a similar trend in the validation cohort (OR = 1.35, p = 0.086). However, rs2281285 showed a trend towards association with increased negative craving in females in both the discovery (beta = 10.16, p = 0.045) and validation samples (OR = 7.11, p = 0.066). In the discovery cohort, rs2281285 was associated with time until relapse after treatment in females (HR = 1.72, p = 0.037); in the validation cohort, it was associated with increased length of sobriety episodes before treatment in males (beta = 13.49, p = 0.001). Our findings suggest that sex-dependent effects of PDYN variants in alcohol dependence are phenotype-specific.

  16. Competitive interactions are mediated in a sex-specific manner by arbuscular mycorrhiza in Antennaria dioica.

    Science.gov (United States)

    Varga, S; Vega-Frutis, R; Kytöviita, M-M

    2017-03-01

    Plants usually interact with other plants, and the outcome of such interaction ranges from facilitation to competition depending on the identity of the plants, including their sexual expression. Arbuscular mycorrhizal (AM) fungi have been shown to modify competitive interactions in plants. However, few studies have evaluated how AM fungi influence plant intraspecific and interspecific interactions in dioecious species. The competitive abilities of female and male plants of Antennaria dioica were examined in a greenhouse experiment. Females and males were grown in the following competitive settings: (i) without competition, (ii) with intrasexual competition, (iii) with intersexual competition, and (iv) with interspecific competition by Hieracium pilosella - a plant with similar characteristics to A. dioica. Half of the pots were grown with Claroideoglomus claroideum, an AM fungus isolated from the same habitat as the plant material. We evaluated plant survival, growth, flowering phenology, and production of AM fungal structures. Plant survival was unaffected by competition or AM fungi. Competition and the presence of AM fungi reduced plant biomass. However, the sexes responded differently to the interaction between fungal and competition treatments. Both intra- and interspecific competition results were sex-specific, and in general, female performance was reduced by AM colonization. Plant competition or sex did not affect the intraradical structures, extraradical hyphae, or spore production of the AM fungus. These findings suggest that plant sexual differences affect fundamental processes such as competitive ability and symbiotic relationships with AM fungi. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

  17. Knowledge translation to fitness trainers: A systematic review

    Directory of Open Access Journals (Sweden)

    Adamo Kristi B

    2010-04-01

    Full Text Available Abstract Background This study investigates approaches for translating evidence-based knowledge for use by fitness trainers. Specific questions were: Where do fitness trainers get their evidence-based information? What types of interventions are effective for translating evidence-based knowledge for use by fitness trainers? What are the barriers and facilitators to the use of evidence-based information by fitness trainers in their practice? Methods We describe a systematic review of studies about knowledge translation interventions targeting fitness trainers. Fitness trainers were defined as individuals who provide exercise program design and supervision services to the public. Nurses, physicians, physiotherapists, school teachers, athletic trainers, and sport team strength coaches were excluded. Results Of 634 citations, two studies were eligible for inclusion: a survey of 325 registered health fitness professionals (66% response rate and a qualitative study of 10 fitness instructors. Both studies identified that fitness trainers obtain information from textbooks, networking with colleagues, scientific journals, seminars, and mass media. Fitness trainers holding higher levels of education are reported to use evidence-based information sources such as scientific journals compared to those with lower education levels, who were reported to use mass media sources. The studies identified did not evaluate interventions to translate evidence-based knowledge for fitness trainers and did not explore factors influencing uptake of evidence in their practice. Conclusion Little is known about how fitness trainers obtain and incorporate new evidence-based knowledge into their practice. Further exploration and specific research is needed to better understand how emerging health-fitness evidence can be translated to maximize its use by fitness trainers providing services to the general public.

  18. Evolutionary diversity and turn-over of sex determination in teleost fishes.

    Science.gov (United States)

    Mank, J E; Avise, J C

    2009-01-01

    Sex determination, due to the obvious association with reproduction and Darwinian fitness, has been traditionally assumed to be a relatively conserved trait. However, research on teleost fishes has shown that this need not be the case, as these animals display a remarkable diversity in the ways that they determine sex. These different mechanisms, which include constitutive genetic mechanisms on sex chromosomes, polygenic constitutive mechanisms, environmental influences, hermaphroditism, and unisexuality have each originated numerous independent times in the teleosts. The evolutionary lability of sex determination, and the corresponding rapid rate of turn-over among different modes, makes the teleost clade an excellent model with which to test theories regarding the evolution of sex determining adaptations. Much of the plasticity in sex determination likely results from the dynamic teleost genome, and recent advances in fish genetics and genomics have revealed the role of gene and genome duplication in fostering emergence and turn-over of sex determining mechanisms. 2009 S. Karger AG, Basel.

  19. Sex Specific Association of Physical Activity on Proximal Femur BMD in 9 to 10 Year-Old Children

    Science.gov (United States)

    Cardadeiro, Graça; Baptista, Fátima; Ornelas, Rui; Janz, Kathleen F.; Sardinha, Luís B.

    2012-01-01

    The results of physical activity (PA) intervention studies suggest that adaptation to mechanical loading at the femoral neck (FN) is weaker in girls than in boys. Less is known about gender differences associated with non-targeted PA levels at the FN or other clinically relevant regions of the proximal femur. Understanding sex-specific relationships between proximal femur sensitivity and mechanical loading during non-targeted PA is critical to planning appropriate public health interventions. We examined sex-specific associations between non-target PA and bone mineral density (BMD) of three sub-regions of the proximal femur in pre- and early-pubertal boys and girls. BMD at the FN, trochanter (TR) and intertrochanter (IT) regions, and lean mass of the whole body were assessed using dual-energy x-ray absorptiometry in 161 girls (age: 9.7±0.3 yrs) and 164 boys (age: 9.7±0.3 yrs). PA was measured using accelerometry. Multiple linear regression analyses (adjusted for body height, total lean mass and pubertal status) revealed that vigorous PA explained 3–5% of the variability in BMD at all three sub-regions in boys. In girls, vigorous PA explained 4% of the variability in IT BMD and 6% in TR BMD. PA did not contribute to the variance in FN BMD in girls. An additional 10 minutes per day of vigorous PA would be expected to result in a ∼1% higher FN, TR, and IT BMD in boys (pgirls. In conclusion, vigorous PA can be expected to contribute positively to bone health outcomes for boys and girls. However, the association of vigorous PA to sub-regions of the proximal femur varies by sex, such that girlś associations are heterogeneous and the lowest at the FN, but stronger at the TR and the IT, when compared to boys. PMID:23209801

  20. Sex-Free and Sex-Related Components of the Eysenck Personality Questionnaire (EPQ Neuroticism Scale among Finnish and Turkish Students

    Directory of Open Access Journals (Sweden)

    Timo Lajunen

    2018-03-01

    Full Text Available Previous studies have suggested that the Neuroticism scale (N of the Eysenck Personality Questionnaire (EPQ reflects two different dimensions, of which the first is sex-related (N-S and the second sex-free (N-A. The N-S component is characterized by social sensitivity and worry while N-A reflects moodiness, irritability and boredom. The purpose of this study was to investigate the internal structure of the N scale in samples of 320 Finnish and 230 Turkish students. The bi-dimensional structure suggested by Francis had an acceptable fit to data in the Finnish and Turkish samples. Higher N-S and N scores correlated with being a woman in the Turkish sample. Neither N nor N-S scores were related to sex in the Finnish sample. ANOVA results showed the main effect of sex on N and N-S scores and the main effect of culture (Finnish vs. Turkish on N and N-A. Turkish women scored higher in N and N-S scales than the other groups. The possible cultural and social reasons for the sex differences on the N scale score were discussed.