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Sexual reproduction implies binary outcomes of competitive interactions for access to male gametes: lifelong virgin females with null fitness vs. mated females with variable (generally nonzero) fitness. Female mating failure has long remained a dormant concept in sexual selection theory in part because it is acutely maladaptive (lifelong virgins that do not reproduce are strongly selected against) and also due to widespread acceptance of the Bateman–Trivers paradigm (anisogamy and correlated sex roles). Based on recent scientific output on lifelong virginity across multiple taxonomic groups in insects (Coleoptera, Diptera, Hemiptera, Lepidoptera, Odonata, Orthoptera, Strepsiptera), female mating failure has become a mainstay of sexual selection over the last decade. Lifelong virginity and senescence (death) are intertwined processes; old virgin females compensate for increased risk of lifelong virginity by becoming less choosy and increasing investment in mating‐related activities. Low rates of female lifelong virginity (<5%) in most natural populations of insects indicate that sex generally ‘works’ due to selective pressures acting on both males and females to enhance lifetime fitness. Mating failures are most common in insects with female flightlessness; these pressures may lead in evolutionary time to transitionary pathways from sexual reproduction to parthenogenesis. Female mating probability is affected by nonlinear density‐dependent processes dependent upon the scale of observation (mate‐encounter Allee effect at large spatial scales, mating interferences between females at small scales). Mate choice and sex role reversal (females being the active sexual partner) are ubiquitous in insects and arachnids with significant paternal investment, but consequences in terms of female lifelong virginity remain unknown. Logistically, conceptual development of female mating failure in insects is most limited by the lack of broadly applicable methods to assess rates of lifetime virginity among flighted females.  相似文献   

3.
KwaZulu-Natal province in South Africa is currently the site of the world's fastest growing HIV/AIDS epidemic, where it is estimated that between 30 and 40 percent of the adult population is seropositive for HIV. With support from local politicians and members of various government ministries, several self-styled guardians of tradition have emerged to form organizations that advocate and conduct regular virginity testing of girls. Reference to the current HIV/AIDS epidemic is central to calls for greater support of this practice. Drawing on original research among Zulu-speaking people in the periurban communities of Durban, this article examines the sociocultural construction of HIV/AIDS and locates the growing popularity of virginity testing within a gendered meaning-making process consistent with commonly held beliefs that the epidemic is the result of women being sexually "out of control." With the social impact of AIDS starting to take its toll in the forms of increasing AIDS-related deaths and a growing population of orphans, I argue that virginity testing is an attempt to manage the epidemic by exerting greater control over women and their sexuality. In addition, virginity testing of girls helps to draw attention away from the role of men in the maturing epidemic, consideration of which has been conspicuously absent in the popular discourse on AIDS at all levels of South African society.  相似文献   

4.
Starvation and enforced virginity induce apoptosis (programmed cell death) in the oocytes of female cockroaches of Nauphoeta cinerea, yet the life‐history outcome differs among fed and starved virgins. Consistent with the hypothesis that oocytes are absorbed to reallocate resources, apoptosis is followed by an increase in future reproduction and longevity in starved virgins. However, apoptosis induction by enforced virginity in fed females results in reduced fecundity and longevity. It is predicted that this life‐history outcome occurs because oocyte apoptosis under these conditions is not part of an adaptive reproductive strategy but simply is the result of cellular ageing and clearance to maintain reproductive synchrony. In the present study, reproductive and somatic allocation are examined over time to test whether resources are recouped by the fat body, reinvested in reproduction or lost altogether when apoptosis is associated with enforced virginity. To assay reproductive investment, the number of ovarioles is counted, apoptosis levels are analysed and the size of all oocytes within the vitellaerium is measured. To assay somatic investment, dry fat body mass is measured. In conjunction with apoptosis, the number of ovarioles declines, whereas the size of surviving oocytes increases. By contrast to the cellular ageing hypothesis, apoptosis associated with enforced virginity appears to be adaptive if resources from sacrificed oocytes are recycled into the survivors to maintain the quality of ageing oocytes. This reinvestment in current reproduction may trade‐off with future reproductive capacity.  相似文献   

5.
A substantial number of women of childbearing age are prescribed psychotropic drugs, and because nearly 50% of pregnancies are unplanned, many women are still taking them upon becoming pregnant. This article reviews the various classes of psychotropic drugs that are commonly used to treat psychiatric disorders--antidepressants, benzodiazepines, antipsychotics, antiepileptics, lithium and monoamine oxidase (MAO) inhibitors--in terms of their safety during pregnancy. Evidence-based information from epidemiologic studies indicates that most psychotropic drugs are relatively safe for use during pregnancy. There is also an increasingly large body of evidence-based information in the literature indicating that it may be more harmful to both the mother and her baby if she is not treated appropriately when suffering from a severe psychiatric disorder. Therefore, it is important for women with psychiatric disorders and their healthcare providers to have access to evidenced-based information about the safety of these drugs when taken during pregnancy to ensure that women make an informed decision as to whether they should continue with the pharmacotherapy they have been using to treat their condition.  相似文献   

6.
Different constructions of the fetus lie at the centre of reproductive, abortion and disability politics. Recent developments mean that, within the same hospital, a fetus may be perceived in contrasting and potentially conflicting ways. It is also argued that the status given to the fetus is directly relevant to the status given to pregnant women. During group discussions facilitated by an ethicist, health-care staff highlighted various perceptions of the fetus which included: person; patient; 'nobody'; commodity. Perhaps not surprisingly in view of the current legal situation, staff tended to claim that it is usually the pregnant women who decides how her fetus will be constructed, and the practitioner who responds to this. However, various ways in which practitioners might influence women's perceptions of their fetus are highlighted, as are some ways in which the perceptions of staff might be influenced. This paper illustrates how sensitive health-care staff will need to be if they are indeed to respond to, rather than shape, women's constructions of their fetus.  相似文献   

7.
P. L Sunderland 《Ethnos》2013,78(1-2):32-58
This article shows ways in which five European American women intertwine and interweave the American discourses of race and ethnicity to talk about themselves as ‘black.’ This black identity both fits with their anti‐racist desires and makes strategic sense in the context of their everyday lives. Importantly, the women do not deny the European side of their heritage, rather they embrace a multi‐racial/ethnic identity. It is argued that the element of choice involved with American ethnic discourse, combined with a general shift toward the allowance of mixed identities, allows this identity construction to be understood as a sensible one. It is further argued that these women's constructions illustrate a type of identity configuration that has become a highly significant option in the United States.  相似文献   

8.
A growing literature shows that the features women find particularly attractive in men vary across the ovulatory cycle. Women furthermore appear to more frequently report attraction to men other than primary partners when they are fertile in their cycle than in the infertile luteal phase. Previous studies have shown that men are more vigilant of or attentive to their primary partners during the fertile phase compared to the luteal phase. This study had several aims: First, to replicate and extend previous findings concerning men's vigilance of partners using male as well as female reports of men's behavior; second, to examine changes in women's behavior toward partners across the cycle; third, to examine ways in which women resist men's attempts to mate-guard across the cycle. Results indicate that (a) men are particularly self-assertive toward partners when their partners are fertile; (b) similarly, women are especially self-assertive toward partners when they are fertile; (c) women report engaging in more behaviors that resist male vigilance and mate guarding when they are fertile, especially in ways that are unobservable to male partners; and (d) these effects are especially strong when women themselves report greater attraction to men other than partners when they are fertile, compared to the luteal phase.  相似文献   

9.
In the space of 50 years, ideals of masculinity in the western end of the Southern Highlands have been radically transformed. Gone, for instance, is the bachelor cult where young boys were grown into men. Drawing upon ethnographic research undertaken over the past decade, in the Lake Kopiago sub‐district in the far north‐western corner of Southern Highlands Province, this paper seeks to document these changing masculinities and explore their portrayal by juxtaposing ‘traditional’ and contemporary growth enhancing spells and courting songs—particularly those composed and sung by men. In doing so, this paper also seeks to explore how guns, marijuana, discos and pornographic movies have come to figure centrally in contemporary notions of masculinity. It will also document how the proliferation of marijuana and small arms has transformed young men with otherwise very little standing in the community into self‐promoted leaders who have taken it upon themselves to publicly police the sexuality of women in increasingly violent ways.  相似文献   

10.
Genetic, clinic and biologic features from three families with Xq fra syndrome are described. First, the authors give their experience for the best ways of culture in order to see the fragile site. Then, they insist upon the main points of each family: in the first, two women have a mental retardation; in the second, a prenatal diagnosis could be made; in the third, treatment with folic acid did not change the IQ but improves the behaviour of two brothers.  相似文献   

11.
In her 2016 article Sherry Ortner discusses what she calls the rise of ‘dark anthropology’: that is, ethnographic work that analyses situations of domination, dispossession, and violence. She, like Joel Robbins ( 2013 ), posits as a counterpoint the emergence of ‘anthropologies of the good,’ which emphasise care and ethics. In this paper I put these two anthropological projects into generative tension through an analysis of HIV‐positive women's lives in Papua New Guinea. In the first part of the paper I demonstrate the ways in which resource extraction has created vulnerabilities to HIV—in part through the coerced marriages of women to powerful landowners. In the second, I discuss ways in which the antiretroviral era has made possible unexpected forms of kindness towards HIV‐positive women. I end the paper with a discussion of what HIV‐positive women mean when they claim that they are happier now than in their pre‐diagnosis lives.  相似文献   

12.
This article is a critique of the myth of “concentrated poverty,” that blames urban ills on spatial morphology, presenting the city as a reified entity. Spatial fetishization neglects to consider the political economy that creates poverty and inequalities. Through the evolution of a ghetto in the Spanish Mediterranean coast, the article addresses spatial segregation, social isolation and territorial stigmatization of the urban poor. Three different contingents of residents—Spaniard, gypsies and Moroccan—are analyzed in their mutual relationships and in their dealings with local and regional governments that produce their neighborhood as a wasteland. Although these groups are strongly segregated among them, the space they inhabit carries a stigma that they share and sets them apart from the larger society. However, they are not isolated from but, on the contrary, fully embedded in the basic elements that constitute capitalism.  相似文献   

13.
Antioxidant and prooxidant properties of carotenoids   总被引:13,自引:0,他引:13  
The ability of dietary carotenoids such as beta-carotene and lycopene to act as antioxidants in biological systems is dependent upon a number of factors. While the structure of carotenoids, especially the conjugated double bond system, gives rise to many of the fundamental properties of these molecules, it also affects how these molecules are incorporated into biological membranes. This, in turn, alters the way these molecules interact with reactive oxygen species, so that the in vivo behavior may be quite different from that seen in solution. The effectiveness of carotenoids as antioxidants is also dependent upon their interaction with other coantioxidants, especially vitamins E and C. Carotenoids may, however, lose their effectiveness as antioxidants at high concentrations or at high partial pressures of oxygen. It is unlikely that carotenoids actually act as prooxidants in biological systems; rather they exhibit a tendency to lose their effectiveness as antioxidants.  相似文献   

14.
Seasonality among animals has an important function in breeding cycles. Research focusing on conception and coital activity in humans has called attention to the possible existence of circannual rhythms in human sexual activity. We studied the diurnal variations, seasonality and subjective sexual preference among young women in Israel-focusing on their first intercourse. The survey included 135 college students who completed a self-report questionnaire. Half of the subjects (50%) reported loss of virginity during the summer with an almost equal distribution among the other seasons. Over 85% of the subjects had their first intercourse either in the evening or at night. Subjective sexual – seasonal – preference was reported by 44.4% of the subjects but no correlation was found between the preferred season and actual loss of virginity; except for the autumn “preferers”. Our study supports previous research generalizing the sociological explanation for seasonality of the first intercourse.  相似文献   

15.

Different constructions of the fetus lie at the centre of reproductive, abortion and disability politics. Recent developments mean that, within the same hospital, a fetus may be perceived in contrasting and potentially conflicting ways. It is also argued that the status given to the fetus is directly relevant to the status given to pregnant women. During group discussions facilitated by an ethicist, health-care staff highlighted various perceptions of the fetus which included: person; patient; 'nobody'; commodity. Perhaps not surprisingly in view of the current legal situation, staff tended to claim that it is usually the pregnant woman who decides how her fetus will be constructed, and the practitioner who responds to this. However, various ways in which practitioners might influence women's perceptions of their fetus are highlighted, as are some ways in which the perceptions of staff might be influenced. This paper illustrates how sensitive health-care staff will need to be if they are indeed to respond to, rather than shape, women's constructions of their fetus.  相似文献   

16.
This article explores the relationships between culture and therapy among patients from three contrasting Israeli groups: Persian, Ashkenazi and Moroccan Jews. The population studied is composed of persons who came to Jerusalem mental health clinics for consultation and treatment. Emphasis is placed upon the patients' conceptions and beliefs regarding health and illness as well as their actual behavior in this sphere. Systematic contrasts among the three groups are analyzed, and the ways these differences influence the treatment process are also discussed.The research was conducted by a multidisciplinary team including a psychiatrist (Krasilovsky) and three anthropologists (Minuchin-Itzigsohn, Ben-Shaoul, Weingrod). It was initiate and sponsored by Talbieh Hospital, Jerusalem, a psychiatric hospital belonging to the General Federation of Labor's Sick Fund. We are grateful to the Jerusalem Center for Anthropological Studies and its director, Dr. Edgar Siskin, for generous support. We should like to thank Dr. Eileen Basker and Prof. Virginia R. Dominguez for their extensive assistance in editing and translating. We also wish to thank Dr. Ram Aronson, director of the clinic at Talbieh Hospital, Dr. Jose Itzigsohn, director of the clinic at Ezrat Nashim Hospital, and Dr. Shlomo Litman, director of the clinic at Eitanim Hospital, and to express our appreciation to the staffs of all the clinics for their understanding of the significance of the research and for their help. We thank all of the patients who participated in this study. Finally, we wish to express our thanks to the editor of CMP and the anonymous readers for their many helpful suggestions.  相似文献   

17.
Seasonality among animals has an important function in breeding cycles. Research focusing on conception and coital activity in humans has called attention to the possible existence of circannual rhythms in human sexual activity. We studied the diurnal variations, seasonality and subjective sexual preference among young women in Israel-focusing on their first intercourse. The survey included 135 college students who completed a self-report questionnaire. Half of the subjects (50%) reported loss of virginity during the summer with an almost equal distribution among the other seasons. Over 85% of the subjects had their first intercourse either in the evening or at night. Subjective sexual - seasonal - preference was reported by 44.4% of the subjects but no correlation was found between the preferred season and actual loss of virginity; except for the autumn “preferers”. Our study supports previous research generalizing the sociological explanation for seasonality of the first intercourse.  相似文献   

18.
BackgroundSome modifiable risk factors have been independently associated with breast cancer (BC) risk in Moroccan women, but no studies have investigated their joint association. This study aimed to investigate the association between a Healthy Lifestyle Index (HLI) score and BC risk among Moroccan women.MethodsIn this case–control study, 300 incident BC cases and 300 controls, matched by age and area of residence were recruited. Cases were women newly-diagnosed with histopathologically–confirmed BC at the University Hospital in Fez, Morocco. Controls were randomly selected healthy women recruited from 6 primary health centers in Fez. HLI scores developed within this study were assigned to participants based on 11 factors (red and processed meat, white meat, cream, cheese, fish, fruit and vegetables, physical activity, BMI, smoking, alcohol consumption, and breastfeeding), where 0 was given to unhealthy and 0.5 or 1 to healthy levels of each factor. Conditional and unconditional logistic regression models were used to assess the association between HLI scores and BC risk.ResultsMean of HLI scores were 8.1 (±1.1) and 9.0 (±0.9) in cases and controls, respectively, p < 0.01. After adjusting for potential confounders, one-point increment in the HLI score was associated with 56% (95% CI, CI: 39–68%), 49% (95% CI: 30–63%), and 59% (95% CI: 40–72%) lower risks of BC in all, premenopausal, and postmenopausal women, respectively.ConclusionHigh HLI scores were associated with decreased risk of BC in Moroccan women. These findings suggest that BC prevention policies should include strategies for engaging Moroccan women in healthy lifestyles.  相似文献   

19.
In this article, two ways that HIV-positive drug users survive under the supervision of law enforcement agencies, community health organizations, and social welfare offices are differentiated. First, strategies are long-ranging and often carefully planned, and they involve conscious utilization and manipulation of bureaucratic processes. Second, tactics are short-ranging and often haphazard, and they are used to survive on daily or weekly bases, with entrenched problems and structural solutions avoided or ignored. Data from three years of ethnographic fieldwork with 14 methamphetamine-using HIV-positive men who have sex with men in San Diego, California is used to expand upon these two categories, explaining the different, often ineffectual, ways these men accessed care, services, shelter, drugs, and companionship. This article also examines the policy implications of taking in consideration these different kinds of survival methods, arguing for intensive client-specific interventions when working with long-term addicts with multiple health problems.  相似文献   

20.
Chinese communities in East Asia are undergoing great economic and social change. The result includes material prosperity but also worsening mental and social health indices. Epidemiological studies clarify the magnitude of these problems and the particular vulnerability of women and the elderly. Ethnographic studies indicate that moral experience is also changing, and that with it subjectivity is being altered in ways that are of concern. And yet it is not clear, in historical perspective, how to assess these changes when they are compared to the extraordinarily difficult experiences of the Chinese over most of the Century.  相似文献   

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