92 resultados para Female orgasm


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Odours of vertebrates often contain information about the major histocompatibility complex (MHC), and are used in kin recognition, mate choice or female investment in pregnancy. It is, however, still unclear whether MHC-linked signals can also affect male reproductive strategies. We used horses (Equus caballus) to study this question under experimental conditions. Twelve stallions were individually exposed either to an unfamiliar MHC-similar mare and then to an unfamiliar MHC-dissimilar mare, or vice versa. Each exposure lasted over a period of four weeks. Peripheral blood testosterone levels were determined weekly. Three ejaculates each were collected in the week after exposure to both mares (i.e. in the ninth week) to determine mean sperm number and sperm velocity. We found high testosterone levels when stallions were kept close to MHC-dissimilar mares and significantly lower ones when kept close to MHC-similar mares. Mean sperm number per ejaculate (but not sperm velocity) was positively correlated to mean testosterone levels and also affected by the order of presentation of mares: sperm numbers were higher if MHC-dissimilar mares were presented last than if MHC-similar mares were presented last. We conclude that MHC-linked signals influence testosterone secretion and semen characteristics, two indicators of male reproductive strategies.

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BACKGROUND AND AIMS: The coexistence of hermaphrodites and female-sterile individuals, or androdioecy, has been documented in only a handful of plants and animals. This study reports its existence in the plant species Cardamine amara (Brassicaceae), in which female-sterile individuals have shorter pistils than seed-producing hermaphrodites. METHODS: Morphological analysis, in situ manual pollination, microsatellite genotyping and differential gene expression analysis using Arabidopsis microarrays were used to delimit variation between female-sterile individuals and hermaphrodites. KEY RESULTS: Female sterility in C. amara appears to be caused by disrupted ovule development. It was associated with a 2.4- to 2.9-fold increase in clonal propagation. This made the pollen number of female-sterile genets more than double that of hermaphrodite genets, which fulfils a condition of co-existence predicted by simple androdioecy theories. When female-sterile individuals were observed in wild androdioecious populations, their ramet frequencies ranged from 5 to 54 %; however, their genet frequencies ranged from 11 to 29 %, which is consistent with the theoretically predicted upper limit of 50 %. CONCLUSIONS: The results suggest that a combination of sexual reproduction and increased asexual proliferation by female-sterile individuals probably explains the invasion and maintenance of female sterility in otherwise hermaphroditic populations. To our knowledge, this is the first report of the coexistence of female sterility and hermaphrodites in the Brassicaceae.

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BACKGROUND: Hallux valgus is one of the most common forefoot problems in females. Studies have looked at gait alterations due to hallux valgus deformity, assessing temporal, kinematic or plantar pressure parameters individually. The present study, however, aims to assess all listed parameters at once and to isolate the most clinically relevant gait parameters for moderate to severe hallux valgus deformity with the intent of improving post-operative patient prognosis and rehabilitation. METHODS: The study included 26 feet with moderate to severe hallux valgus deformity and 30 feet with no sign of hallux valgus in female participants. Initially, weight bearing radiographs and foot and ankle clinical scores were assessed. Gait assessment was then performed utilizing pressure insoles (PEDAR®) and inertial sensors (Physilog®) and the two groups were compared using a non-parametric statistical hypothesis test (Wilcoxon rank sum, P<0.05). Furthermore, forward stepwise regression was used to reduce the number of gait parameters to the most clinically relevant and correlation of these parameters was assessed with the clinical score. FINDINGS: Overall, the results showed clear deterioration in several gait parameters in the hallux valgus group compared to controls and 9 gait parameters (effect size between 1.03 and 1.76) were successfully isolated to best describe the altered gait in hallux valgus deformity (r(2)=0.71) as well as showed good correlation with clinical scores. INTERPRETATION: Our results, and nine listed parameters, could serve as benchmark for characterization of hallux valgus and objective evaluation of treatment efficacy.

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Violation of Mendel's Law of Segregation by selfish X chromosomes that favour their own transmission is known for a number of organisms. Now, a new study reveals sex-ratio distortion favouring males and explains previously puzzling sex ratios in a Mediterranean shrub.

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While problematic Internet use is recognized to be predominant among male adolescents, a female trend is gradually becoming apparent. Our study aimed at investigating the characteristics of female Internet users and distinguishing between the online activities of problematic and regular Internet users' on school days. Data were retrieved from a cross-sectional survey of a representative sample of 3067 8th graders in the canton of Vaud, Switzerland, that completed an online questionnaire in 2012. Only females were included. Based on the Internet addiction test, the sample was divided into regular (RUs) (IAT < 50, n = 1339) and problematic users (PIUs) (IAT ≥ 50, n = 201). Groups were compared regarding sociodemographic variables, online activities, devices used to access the Internet, substance use, and physical activity. Significant variables were included in a backward logistic regression. At the multivariate level, PIUs were more prone to spend time online for leisure activities (odds ratio [OR] 2.38) and to access the Internet through a smartphone (OR 1.79) or tablet (OR 1.84). PIUs were less likely to be physically active (OR 0.86) and more likely to present poor emotional well-being (OR 2.67) and to smoke (OR 1.88). CONCLUSION: A sizeable percentage of female adolescents are problematic Internet users. When performing a comprehensive biopsychosocial assessment, teenagers owning numerous devices to access the Internet, presenting other health-compromising behaviors or poor emotional well-being should be specifically targeted. WHAT IS KNOWN: ? Problematic Internet use has been found to be predominant among males. ? Specific online activities have been identified as being addictive for young men and women differently. ? Problematic Internet use is known to impact in several ways the general health and daily functioning of teenagers. What is New: ? A sizeable percentage of female adolescents are problematic Internet users. ? Tobacco use, poor well-being, as well as compact devices to access the Internet are positively related to problematic Internet use. ? In addition to their special interest in online social and communicational activities, female problematic Internet users also reported more online gambling.

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Work-life issues have become a major concern across Western societies with the objective to promote women's careers and well-being. However, despite growing attempts to increase the number of women in senior management positions in European countries, such as Switzerland, they remain highly underrepresented. Inspired from the cultural approach in psychology, this article focuses on these women's concrete everyday life to understand how they articulate different life domains and how this influences their subjective well-being. A narrative approach based on reflexivity is adopted to analyze women's activity. Results show meaning intertwinements between life priorities that are often conflicting. Two psychological functions are identified: the feeling of control and the letting go of control. Each of these contributes to women's subjective well-being through the use of diversified supports, but their structuring roles appear only in relation to one another. Results are discussed in the light of existing literature and of their implications.

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BACKGROUND AND AIMS: Formerly obese patients having undergone Roux-en-Y gastric bypass (RYGB) display both an accelerated digestion and absorption of carbohydrate and an increased plasma glucose clearance rate after meal ingestion. How RYGB effects postprandial kinetics of dietary lipids has yet not been investigated. METHODS: Plasma triglyceride (TG), apoB48, total apoB, bile acids (BA), fibroblast growth factor 19 (FGF19), and cholecystokinin (CCK) were measured in post-absorptive conditions and over 4-h following the ingestion of a mixed test meal in a cross-sectional, pilot study involving 11 formerly obese female patients 33.8 ± 16.4 months after RYGB surgery and in 11 weight- and age-matched female control participants. RESULTS: Compared to controls, RYGB patients had faster (254 ± 14 vs. 327 ± 7 min, p < 0.05) and lower (0.14 ± 0.04 vs. 0.35 ± 0.07 mM, p < 0.05) peak TG responses, but their peak apoB48 responses tended to be higher (2692 ± 336 vs. 1841 ± 228 ng/ml, p = 0.09). Their postprandial total BA concentrations were significantly increased and peaked earlier after meal ingestion than in controls. Their FGF19 and CCK concentrations also peaked earlier and to a higher value. CONCLUSIONS: The early postprandial apoB48 and BA responses indicate that RYGB accelerated the rate of dietary lipid absorption. The lower postprandial peak TG strongly suggests that the RYGB simultaneously increased the clearance of TG-rich lipoproteins. CLINICAL TRIAL REGISTRATION: NCT01891591.

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BACKGROUND AND AIMS: Smoking is a crucial environmental factor in inflammatory bowel disease (IBD). However, knowledge on patient characteristics associated with smoking, time trends of smoking rates, gender differences and supportive measures to cease smoking provided by physicians is scarce. We aimed to address these questions in Swiss IBD patients. METHODS: Prospectively obtained data from patients participating in the Swiss IBD cohort study was analysed and compared to the general Swiss population (GSP) matched by age, sex and year. RESULTS: Among a total of 1770 IBD patients analysed (49.1% male), 29% are current smokers. More than twice as many patients with Crohn's disease (CD) are active smokers compared to ulcerative colitis (UC, 39.6% vs. 15.3%, p<0.001). In striking contrast to the GSP, significantly more women than men with CD smoke (42.8% vs. 35.8%, p=0.025), with also an overall significantly increased smoking rate compared to the GSP in women but not men. The vast majority of smoking IBD patients (90.5%) claim to never have received any support to achieve smoking cessation, significantly more in UC compared to CD. We identify a significantly negative association of smoking and primary sclerosing cholangitis, indicative of a protective effect. Psychological distress in CD is significantly higher in smokers compared to non-smokers, but does not differ in UC CONCLUSIONS: Despite well-established detrimental effects, smoking rates in CD are alarmingly high with persistent and stagnating elevations compared to the GSP, especially in female patients. Importantly, there appears to be an unacceptable underuse of supportive measures to achieve smoking cessation.

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This paper explores the construction of female abject beings in Colombian contemporary media and culture comparing a character in the 2010 telenovela Chepe Fortuna named Venezuela, and the cultural representation of Piedad Córdoba. I argue that the construction of these two characters as abject beings is coherent with the dominant discourse of Alvaro Uribe's national project, which relied on a strong nationalist rhetoric based on binary oppositions of the type "we/other." In this context both Chepe Fortuna's Venezuela and Piedad Córdoba are constructed as "other." While Venezuela's abjection is partly effected on the basis of her being fat and black, Córdoba's is on the basis of her being a left-wing politician, and mediated through her being a black female. These two instances evidence an approach to femaleness that goes hand-in-hand with particular understandings of female subjectivity within current post-feminist paradigms.

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Why females of many species mate multiply in the absence of direct benefits remains an open question in evolutionary ecology. Interacting and mating with multiple males can be costly to females in terms of time, resources, predation risk, and disease transmission. A number of indirect genetic benefits have been proposed to explain such behaviors, but the relative importance of these mechanisms in natural systems remains unclear. We tested for several direct and indirect benefits of polyandry in the walking stick Timema cristinae. We found no evidence of direct benefits with respect to longevity or fecundity. However, male x female genotypic interactions affected egg-hatching success and offspring production independent of relatedness, suggesting that mating with certain males benefits females and that the best male may differ for each female. Furthermore, multiply mated females biased paternity toward one or few males, and the extent of this bias was positively correlated to egg-hatching success. Our data, therefore, provide evidence for indirect benefits through compatibility effects in this species. By mating multiply, females may improve their chances of mating with a compatible male if compatibility cannot be assessed before mating. Such compatibility effects can explain the evolution and maintenance of polyandry in Timema and many other species.

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Previous research suggests that female physicians may not receive appropriate credit in patients' eyes for their patient-centered skills compared to their male counterparts. An experiment was conducted to determine whether a performance of higher (versus lower) verbal patient-centeredness would result in a greater difference in analogue patient satisfaction for male than female physicians. Two male and two female actors portrayed physicians speaking to a patient using high or low patient-centered scripts while not varying their nonverbal cues. One hundred ninety-two students served as analogue patients by assuming the patient role while watching one of the videos and rating their satisfaction and other evaluative responses to the physician. Greater verbal patient-centeredness had a stronger positive effect on satisfaction and evaluations for male than for female physicians. This pattern is consistent with the hypothesis that the different associations between patient-centeredness and patients' satisfaction for male versus female physicians occur because of the overlap between stereotypical female behavior and behaviors that comprise patient-centered medical care. If this is the case, high verbal patient-centered behavior by female physicians is not recognized as a marker of clinical competence, as it is for male physicians, but is rather seen as expected female behavior.

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Pendant quatre semaines, les étudiant(e)s en médecine de 3e année de l'Université de Lausanne mènent une enquête dans la communauté sur le sujet de leur choix. L'objectif de ce module est de faire découvrir aux futurs médecins les déterminants non biomédicaux de la santé, de la maladie et de l'exercice de la médecine : les styles de vie, les facteurs psychosociaux et culturels, l'environnement, les décisions politiques, les contraintes économiques, les questions éthiques, etc. Par groupes de cinq, les étudiant(e)s commencent par définir une question de recherche originale et en explorent la littérature scientifique. Leur travail de recherche les amène à entrer en contact avec le réseau d'acteurs de la communauté concernés, professionnels ou associations de patients dont ils analysent les rôles et influences respectives. Chaque groupe est accompagné par un(e) tuteur(trice), enseignant(e) de la Faculté de biologie et de médecine de l'Université de Lausanne. Les étudiant(e)s présentent la synthèse de leurs travaux pendant un congrès de deux jours à la fin du module. Quatre travaux parmi les plus remarquables ont été choisis pour être publiés dans la Revue Médicale Suisse et Primary Care.

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Male mating behaviors harmful to females have been described in a wide range of species. However, the direct and indirect fitness consequences of harmful male behaviors have been rarely quantified for females and their offspring, especially for long-lived organisms under natural conditions. Here, lifetime and intergenerational consequences of harmful male interactions were investigated in female common lizards (Lacerta vivipara) using field experiments. We exposed females to male harm by changing the population sex ratio from a normal female-biased to an experimental male-biased sex ratio during the first experimental year. Thereafter, females and their first generation of offspring were monitored during two additional years in a common garden with a female-biased sex ratio. We found strong immediate fitness costs and lower lifetime reproductive success in females subjected to increased male exposure. The immediate fitness costs were partly mitigated by direct compensatory responses after exposure to male excess, but not by indirect benefits through offspring growth, offspring survival, or mating success of offspring. These results support recent empirical findings showing that the direct costs of mating are not outweighed by indirect benefits.

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Sex allocation theory predicts that facultative maternal investment in the rare sex should be favoured by natural selection when breeders experience predictable variation in adult sex ratios (ASRs). We found significant spatial and predictable interannual changes in local ASRs within a natural population of the common lizard where the mean ASR is female-biased, thus validating the key assumptions of adaptive sex ratio models. We tested for facultative maternal investment in the rare sex during and after an experimental perturbation of the ASR by creating populations with female-biased or male-biased ASR. Mothers did not adjust their clutch sex ratio during or after the ASR perturbation, but produced sons with a higher body condition in male-biased populations. However, this differential sex allocation did not result in growth or survival differences in offspring. Our results thus contradict the predictions of adaptive models and challenge the idea that facultative investment in the rare sex might be a mechanism regulating the population sex ratio.