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1.
Outwardly rectifying Cl channels were originally thought to be the central element in cystic fibrosis. The role of these channels in CF was questioned to such an extent that doubts were rasied about the validity of the original experiments. Recent data reestablishes a role for outwardly rectifying Cl channels (ORCC) in CF and suggests that the protein encoded by the CF gene, the cystic fibrosis transmembrane regulator (CFTR), can effect the regulation of more than one channel in the airway. This minireview deals with the rise, fall, and resurrection of the role of outwardly rectifying Cl channels in CF.  相似文献   

2.
F C Ho  R C Johnson 《Social biology》1990,37(1-2):44-51
A comparison of intra- and inter-ethnic divorce rates in Hawaii showed that inter-ethnic marriages resulted in a higher proportion of divorces than did intra-ethnic marriages when the marriage data used had to do with all marriages occurring in Hawaii. However, a sizeable portion of marriages in Hawaii are of nonresidents who, if they divorce, probably divorce elsewhere. Nonresident marriages are chiefly intra-ethnic marriages of Caucasians. When examining the proportions of divorces to resident marriages, within-group marriages are more at risk than inter-ethnic marriages. As in prior research, persons who marry members of other racial/ethnic groups tend to marry persons from groups with income levels similar to their own. As in previous reports, some cross-ethnic combinations appeared more at risk for divorce than did others. Group income appeared to be a predictor of risk. When considering only resident marriages as related to divorces, those marriages in which the bride was from a higher income group than the groom were at a significantly greater risk for divorce than marriage in which the bride came from an income group lower than that of the groom.  相似文献   

3.
Over 4,000 dyadic groupings in two large shopping malls were classified by age and sex of individual members as they passed along a well-defined exit path. The observations were carried out at times and places when a demographic cross-section of the city was likely to be seen, and where there were no rigid constraints on the group composition that appeared. The data were subjected to computer analysis, and observed frequencies of specified age-sex dyads were compared by chi-square statistics to expected frequencies based on a binomial distribution. A female mating strategy at ages 21–32 years and two different male strategies at ages 24–32 and 39–50 years were revealed. The observed strategies correlate with the reproductive, marital, and divorce statistics of the locale. The results are discussed in terms of inclusive fitness maximized by a preference for monogamy in females and the practice of serial polygyny by some males.  相似文献   

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Jin X  Li S  Feldman MW 《Social biology》2005,52(1-2):18-46
Using data from two surveys in three counties in which the prevalence of uxorilocal marriage differs greatly, this article analyzes the effects of marriage form, individual, family, and social factors on age at first marriage and spousal age difference. The results show that, under the Chinese patrilineal joint family system, compared with the dominant virilocal marriage form, uxorilocal marriage significantly lowers women's age at first marriage, increases men's age at first marriage, and consequently increases spousal age difference. Education, number of brothers, adoption status, marriage arrangement, and marriage circle also significantly affect age at first marriage for both genders. Age at first marriage and spousal age difference vary greatly among the three counties. These findings address the process and consequences of change in rural family and marriage customs during the current demographic and social transition and may help to promote later marriage and later childbearing under the present low fertility conditions in rural China.  相似文献   

8.
The high occurrence of social monogamy in birds has led to questions about partner fidelity, or the perennial nature of monogamy from one breeding season to another. Despite the evolutionary advantages of partner fidelity, divorce occurs among 95% of bird species. We aimed to describe patterns of divorce and partner fidelity in five seabird species breeding in Arctic and Antarctic regions and investigated the influence of breeding status on pair bond maintenance. For four out of the five species considered, we observed low divorce rates (respectively 1.9%, 3.3%, 2.5%, and 0.0% for Brünnich''s guillemot, glaucous gull, Antarctic petrel, and south polar skua), while the divorce rate was much higher (19.1%) for the black‐legged kittiwake. For kittiwakes, the divorce rate was lower for pairs that managed to raise their chick to 15 days of age, while the effect of breeding success on divorce in the four other species could not be tested due to the rareness of divorce events. Our results emphasize the potentially large temporal (interannual) variations that should be taken into account in understanding divorce and partner fidelity in seabirds.  相似文献   

9.
Anthropologists have long been interested in the survival of Indian cultural traits in the New World. In this article, we present results of an ongoing project with a Costa Rican community that descends from East Indian indentured servants. We focus on the group's marriage patterns and how these patterns might have helped keep the community as a cohesive ethnic group. We investigate the group's level of inbreeding by computing the inbreeding coefficient using two different methods. We show that the community has been successful at keeping its inbreeding low, despite its small size, by allowing marriage with nonmembers of the community. We propose that unless consanguineous marriages are allowed virtually all of the community's marriages will be with noncommunity members. Absorption into tourism, as well as the community's staunch avoidance of consanguineous marriages and virtually universal marriage with noncommunity members, will likely contribute to their disappearance as a viable ethnic group.  相似文献   

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Using data from the first Census data set that includes complete measures of male biological fertility for a large-scale probability sample of the U.S. population (the 2014 wave of the Study of Income and Program Participation-N = 55,281), this study shows that high income men are more likely to marry, are less likely to divorce, if divorced are more likely to remarry, and are less likely to be childless than low income men. Men who remarry marry relatively younger women than other men, on average, although this does not vary by personal income. For men who divorce who have children, high income is not associated with an increased probability of having children with new partners. Income is not associated with the probability of marriage for women and is positively associated with the probability of divorce. High income women are less likely to remarry after divorce and more likely to be childless than low income women. For women who divorce who have children, high income is associated with a lower chance of having children with new partners, although the relationship is curvilinear. These results are behavioral evidence that women are more likely than men to prioritize earning capabilities in a long-term mate and suggest that high income men have high value as long-term mates in the U.S.  相似文献   

12.
H Fukurai  J P Alston 《Social biology》1992,39(3-4):257-277
This paper examines the ecological determinants of contemporary Japanese divorce rates on the prefectural level. LISREL and computer-generated graphics are the analytic methods used. The aggregate level of analysis demands the use of the ecological model which posits that demographic changes, economic activities, migration patterns, and the level of urbanization are significant predictors of divorce rate. Our analysis demonstrates that sex ratio, female labor force participation, female in-migration patterns, population increase, and net household income all play a significant role in affecting the divorce rate. Our findings also confirm the well-supported hypothesis that both population density and modernization positively influence modern Japan's divorce rates. The residual analysis also points out that in order to account for the large proportion of the unexplained variance of Japanese divorce, behavioral-related variables and island- or prefecture-specific dimensions need to be included in the ecological model of divorce.  相似文献   

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Patterns of reproductive effort in male ungulates   总被引:5,自引:0,他引:5  
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1 We monitored flowering and fruiting of individual male and female plants of Oemleria cerasiformis over a 6-year period in a population in western Canada, and calculated fruit set (percentage of pistils maturing) and reproductive effort (RE) (gram of reproductive tissue per gram of leaf).
2 Over 6 years, male O. cerasiformis had on average much lower total RE, but much higher RE at flowering, than females.
3 In males, strong correlations between RE and light suggested that investment in reproduction was largely determined by light levels. There were strong positive correlations of RE between years, with no evidence of periodic fluctuations.
4 In females, in contrast to males, RE at flowering was not related to light. However, fruit set was strongly correlated with light. Flowering RE and fruit set were uncorrelated in females, indicating that these are affected by different factors.
5 Correlations of RE between years in females, although often significant, were lower than in males, indicating that RE fluctuates more between years in females than in males and may respond to past levels of RE. Flowering may reflect adjustments in response to past reproduction, or may be controlled by resources other than light. Fruit set was not significantly related to previous RE.
6 The greater total RE of females and their limited ability to adjust fruit set are probably major factors contributing to the greater mortality rates of females and the male-biased sex ratios in O. cerasiformis .  相似文献   

16.
Two sample populations, one refugee and one resident, were studied. The frequencies of consanguineous marriages came out to be 49.8%and 55.4%, respectively, for the refugees and the residents. Caste endogamy was dominant both in the residents and the refugees. The mean coefficient of inbreeding was calculated to be 0.0303 for the refugee population and 0.0332 for the resident population samples. First cousin marriage was the dominant type of marriage in both samples; father's brother's daughter (FBD) marriage was more frequent among the refugees while mother's brother's daughter(MBD) marriage was more frequent among the residents. Education has no decreasing effect on the incidence of consanguineous marriages. A significant difference in the pattern of marriages in the refugees is observed after the Saur Revolution of 1979.  相似文献   

17.
Ronen Kadmon  Avi Shmida 《Oecologia》1990,83(1):139-144
Summary This study examines patterns and causes of variation in the reproductive success of the desert annual Stipa capensis. Three nested scales of variation were analyzed: variation between individuals of the same plot, variation between different plots of the same habitat, and variation between different habitats in the same region. Perturbation experiments (irrigation and neighbors removal) were performed to test the effects of heterogeneity in soil water and neighborhood competition on the magnitude of variation in each scale. The results demonstrate that variation of reproductive success was highest within plots, lowest between plots, and moderate between habitats. Soil water heterogeneity contributed to spatial variation in all scales but was most important for differences between habitats. Neighborhood competition increased the variation within plots, but decreased the variation between habitats. The results further demonstrate that water limitation was negatively correlated with the position of the habitat along the run-off/run-on gradient. An opposite trend was obtained for the effect of competition.  相似文献   

18.
Heaton TB  Forste R 《Social biology》1998,45(3-4):194-213
Using data from the World Fertility and Demographic and Health Surveys of Colombia, Peru, and Bolivia, we model the effects of education on three demographic outcomes: the timing of first sexual union, contraceptive use, and fertility. These effects are examined over time and across geographic areas using a multivariate framework. We find substantial improvements in female educational attainment over the last fifty years and a strong relationship between education and the demographic outcomes. Each successive increment in education is associated with declines in the marriage rate, increased contraceptive use, and lower fertility. Education accounts for some of the changes over time in the demographic outcomes, but the pattern varies by outcome, time period, and geographic area. In support of the social diffusion hypothesis, our results indicate that educational differences in reproductive behavior are reduced as the level of development increases and societies pass through their demographic transition.  相似文献   

19.
Kaj Århem 《Ethnos》2013,78(1-2):47-63
This article explores how notions of power, femininity, and ethnicity permeate the discourses of and around girls involved in gangs. I explore how the cholasLatina gang girls ‐ of Foxbury perform and inscribe on their bodies a specific kind of femininity that not only confounds wider community notions of how girls should act, dress, and talk, but throws into question the very gendered category that girls are expected to inhabit.  相似文献   

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