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201.
Urbanization poses threats to earth’s biota, and retention of remnant native habitat in protected areas within expanding urban boundaries may help alleviate threats to wildlife. However, it is unclear for nearly all nonsynanthropic (i.e., not benefiting from an association with humans) species whether vital rates in urban habitats can sustain populations or if populations persist only through immigration from outside the urban boundary. We conducted a three-year study of spotted towhees (Aves: Pipilo maculatus) breeding in four undeveloped parks in Portland, OR, USA, to measure park-specific seasonal reproductive output (F) and annual adult survival (SA). We developed a stochastic model that combined F and SA with an estimate of first-year survival to measure population growth rate (λ) in all parks assumed to be closed to immigration. F differed among parks but SA did not. Relatively high F was possible because many pairs raised >1 brood/season. When combined with empirical estimates of survival through the 30-day period of post-fledging parental care (SD = 0.645), only 2 of 4 parks were self-sustaining (i.e., λ > 1.0). However, SD reflected substantial loss of fledglings to domestic cats (Felis catus). Assuming no loss to cats and either partial compensatory or additive mortality of fledglings substantially improved prospects of population persistence for declining (sink) populations. Moreover, allowing low levels of immigration to sinks reversed population declines in most parks even when vital rates were insufficient to maintain populations. Our results suggest that nonsynanthropic bird species can persist in urban landscapes, but also that offspring mortality in the post-fledging period may be a critical determinant of population viability.  相似文献   
202.
Emotional relationships in infant–mother dyads in families where mothers provided full‐time childcare were compared with those of families where mothers used in‐home childcare providers and family childcare providers (= 245). Infant relationships with childcare providers were also studied. Emotional relationships were adequate in all three childcare arrangements, but infant–mother dyads in in‐home childcare arrangements displayed healthier emotional relationships than infant–mother dyads in mother care arrangements; no differences in the health of emotional relationships with infants emerged among the three types of childcare providers (mother care, in‐home childcare, family childcare). Infant–mother dyads in in‐home childcare arrangements also displayed healthier emotional relationships than infant–in‐home childcare caregiver dyads, but infant–mother and infant–caregiver dyads were comparable in family childcare families. Emotional relationships in infant–mother and infant–caregiver dyads were not correlated, regardless of the type of childcare.  相似文献   
203.
The influence of neoliberalism on culture and subjectivity is well documented. This paper contributes to understanding of how neoliberal ideology enters into the production of subjectivity. While subject formation takes place in multiple and contradictory ways and across multiple social sites, we focus on the increasingly popular media discourse of self-development, and examine it as a technology of neoliberal subjectification. Drawing on Foucauldian understandings, we analyze data from two different newspapers from two different national contexts, both of which are heavily influenced by neoliberalism. Based on our analysis, we detail four interrelated discourses—rationality, autonomy and responsibility, entrepreneurship, and positivity and self-confidence—demonstrating how these discourses constitute the neoliberal subject in ways consonant with neoliberal governmentality. There is no observable resistance to subject positions offered within these discourses. Self-development discourse instills stronger individualism in society, while constraining collective identity, and thus provides social control and contributes to preserving status quo of neoliberal societies.  相似文献   
204.
We examined consistency in self-reports of age at first vaginal sex among 9,399 male and female respondents who participated in Waves III and IV (separated by approximately seven years) of the National Longitudinal Study of Adolescent Health (Add Health). Respondents were coded as consistent if they reported an age at first vaginal intercourse at Wave IV that was within one year of the age they reported at Wave III. Sociodemographic, behavioral, and cognitive predictors of consistency were examined using bivariate and multivariate logistic regression. Overall, 85.43% of respondents were able to provide consistent reports. Among both males and females, consistency was associated with age, years since first vaginal intercourse, race/ethnicity, and lifetime number of other-sex partners in final multivariate models. Respondents who were older and had more recently had their first sexual experience were more likely to be consistent. For females only, those who reported a history of nonparental, physically forced sex were less likely to be consistent. Most young adults consistently report age at first vaginal intercourse, supporting the credibility of retrospective self-reports about salient sexual events such as timing of first vaginal intercourse.  相似文献   
205.
Important resources from family support systems, employment, and educational attainment inhibit the risk of death. Independently, these factors are particularly salient for suicide, but how they combine to affect mortality is less clear. Analyses of National Health Interview Survey data from 1986 to 2004 (N = 935,802), prospectively linked to mortality through 2006 (including 1,238 suicides), reveals a process of compensation in the way work status and family combine to affect adult suicide: Individuals who are not working experience more suicide defense from more protective family support systems than do working adults. But a process of reinforcement occurs in the combination of education and family: More education associates with more protection from the family than does less education. The findings demonstrate how families and resources combine to affect mortality in unique ways.  相似文献   
206.
We estimate the frequencies with which ten voting anomalies (ties and nine voting paradoxes) occur under 14 voting rules, using a statistical model that simulates voting situations that follow the same distribution as voting situations in actual elections. Thus the frequencies that we estimate from our simulated data are likely to be very close to the frequencies that would be observed in actual three-candidate elections. We find that two Condorcet-consistent voting rules do, the Black rule and the Nanson rule, encounter most paradoxes and ties less frequently than the other rules do, especially in elections with few voters. The Bucklin rule, the Plurality rule, and the Anti-plurality rule tend to perform worse than the other eleven rules, especially when the number of voters becomes large.  相似文献   
207.
Rapid sexual involvement may have adverse long‐term implications for relationship quality. This study examined the tempo of sexual intimacy and subsequent relationship quality in a sample of married and cohabiting men and women. Data come from the Marital and Relationship Survey, which provides information on nearly 600 low‐ to moderate‐income couples living with minor children. Over one third of respondents became sexually involved within the first month of the relationship. Bivariate results suggested that delaying sexual involvement was associated with higher relationship quality across several dimensions. The multivariate results indicated that the speed of entry into sexual relationships was negatively associated with marital quality, but only among women. The association between relationship tempo and relationship quality was largely driven by cohabitation. Cohabiting may result in poorer quality relationship because rapid sexual involvement early in the romantic relationship is associated with entrance into shared living.  相似文献   
208.
It is commonly believed that men think about sex much more often than do women, but the empirical evidence in this area is fairly weak. By means of a golf tally counter, 283 college students kept track of their thoughts pertaining to food, sleep, or sex for one week. Males reported significantly more need-based cognitions overall, but there was no significant interaction between sex of participant and type of cognition recorded. Therefore, although these young men did think more about sex than did young women, they also thought more about food and sleep. In contrast, a retrospective estimated frequency of need-based cognitions obtained at the start of the study revealed a sex difference in sexual cognitions, but not thoughts about eating or sleeping. Erotophilia and sexual desirability responding were significant predictors of frequency of sexual cognitions for women, but not for men. Overall, erotophilia was a better predictor of sexual cognition than was sex of participant. Taken as a whole, the results suggest that, although there may be a sex difference in sexual cognitions, it is smaller than is generally thought, and the reporting is likely influenced by sex role expectations.  相似文献   
209.
Many studies have documented significant differences in sexual desire between individuals of European and Chinese descent, but few have examined the mechanisms that underlie these differences. A recent study of university students found that sex guilt is one mechanism by which culture influences sexual desire among Chinese and Euro-Canadian women. The goal of this study was to examine whether sex guilt also mediates the relationship between ethnicity and sexual desire in a sample that is more representative of women in the general population. Euro-Canadian (n = 78; mean age = 42.1 years) and Chinese (n = 87; mean age = 42.8 years) women were recruited from the community. Euro-Canadian women reported greater sexual desire and less sex guilt. In the entire sample, sex guilt mediated the relationship between ethnicity and sexual desire such that the Chinese women reported greater sex guilt, which, in turn, was associated with lower sexual desire. Among the Chinese women, sex guilt mediated the relationship between mainstream acculturation (degree of Westernization) and sexual desire such that more Westernized Chinese women reported less sex guilt, which, in turn, was associated with greater sexual desire. These results support recent findings and further suggest that sex guilt may be one mechanism by which ethnicity affects sexual desire.  相似文献   
210.
We used data from a randomized controlled study of Oxford House (OH), a self-run, self-supporting recovery home, to conduct a cost-benefit analysis of the program. Following substance abuse treatment, individuals that were assigned to an OH condition (n = 68) were compared to individuals assigned to a usual care condition (n = 61). Economic cost measures were derived from length of stay at an Oxford House residence, and derived from self-reported measures of inpatient and outpatient treatment utilization. Economic benefit measures were derived from self-reported information on monthly income, days participating in illegal activities, binary responses of alcohol and drug use, and incarceration. Results suggest that OH compared quite favorably to usual care: the net benefit of an OH stay was estimated to be roughly $29,000 per person on average. Bootstrapped standard errors suggested that the net benefit was statistically significant. Costs were incrementally higher under OH, but the benefits in terms of reduced illegal activity, incarceration and substance use substantially outweighed the costs. The positive net benefit for Oxford House is primarily driven by a large difference in illegal activity between OH and usual care participants. Using sensitivity analyses, under more conservative assumptions we still arrived at a net benefit favorable to OH of $17,830 per person.  相似文献   
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