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121.
Between 1970 and 1990, China experiencoed a rapid and sharp fertility decline—from total fertility rates of approximately six births to two. The degree to which Chinese fertility has continued to fall after 1990 is controversial. We use survey data from the 1997 National Population and Reproductive Health Survey and from the 2001 Reproductive Health and Family Planning Survey to document recent trends in Chinese fertility. Our estimates provide further evidence that China's fertility is well below‐replacement level at the turn of the twenty‐first century—with TFR levels of approximately 1.5 children per woman. Trends in parity‐specific cohort fertility by age also suggest below replacement completed fertility for cohorts still in the childbearing years. In the article's second section, we identify key components of low period fertility in order to frame our discussion of two questions: 1) in what ways is Chinese low fertility different from/similar to that in other low‐fertility countries? And 2) what are the likely future trends in Chinese fertility?  相似文献   
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BackgroundSevere perineal tears sustained during childbirth cause significant distress and morbidity amongst women. The objective of this study was to compare the use of straight scissors for cutting an episiotomy with the use of curved scissors, which are designed to curve away from the anal sphincter.MethodsWe used a single-centre, randomised feasibility trial. The intervention was the use of curved scissors. Women were recruited during a prenatal visit and randomised in the delivery suite, when it became clear that an episiotomy was required. The feasibility outcomes were the proportion of women able to be recruited, randomised and followed up. We also calculated the incidence of obstetric anal sphincter injury when either straight or curved scissors were used to cut an episiotomy. Other outcomes assessed were pain, length of hospital stay, perineal infection and perineal dehiscence.ResultsOf the 155 patients recruited in the prenatal period, only 20 (12.9%) were eventually randomised at birth. The main reasons for the high loss were that women either did not have a vaginal delivery (38, 24.5%), or they did not need an episiotomy (72, 46.5%). Rates of obstetric anal sphincter injury and other outcomes were similar between groups.DiscussionAnal sphincter injury during childbirth remains an important problem. Although the use of curved scissors provides a theoretical solution, we found that the high attrition rate made feasibility of conducting a suitably powered, randomised trial using the current design untenable. Alternative strategies have been suggested to make any future study more viable.  相似文献   
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Because marriage has been denied to same-sex couples, it is likely that the meaning and significance ascribed to non-marital cohabitation may be unique. Further, it is unclear whether same-sex couples view marriage as important to their relationships, and if they do, why. Using qualitative data from 526 individuals in cohabiting same-sex relationships across 47 states, we explored (1) the meaning and significance of cohabitation and (2) the perceived importance of legal marriage to the relationship. Participants viewed cohabitation as significant, most commonly because it indicates long-term commitment, provides emotional support, makes the couple a family, and allows them to share life together. Marriage was perceived as important to a majority (90%), most commonly because it confers financial and legal benefits, relational legitimacy, and demonstrates the same commitment as different-sex couples. Overall, findings highlight the symbolic significance of cohabitation and importance of access to legal marriage to adults in same-sex relationships.  相似文献   
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The Simon's two‐stage design is the most commonly applied among multi‐stage designs in phase IIA clinical trials. It combines the sample sizes at the two stages in order to minimize either the expected or the maximum sample size. When the uncertainty about pre‐trial beliefs on the expected or desired response rate is high, a Bayesian alternative should be considered since it allows to deal with the entire distribution of the parameter of interest in a more natural way. In this setting, a crucial issue is how to construct a distribution from the available summaries to use as a clinical prior in a Bayesian design. In this work, we explore the Bayesian counterparts of the Simon's two‐stage design based on the predictive version of the single threshold design. This design requires specifying two prior distributions: the analysis prior, which is used to compute the posterior probabilities, and the design prior, which is employed to obtain the prior predictive distribution. While the usual approach is to build beta priors for carrying out a conjugate analysis, we derived both the analysis and the design distributions through linear combinations of B‐splines. The motivating example is the planning of the phase IIA two‐stage trial on anti‐HER2 DNA vaccine in breast cancer, where initial beliefs formed from elicited experts' opinions and historical data showed a high level of uncertainty. In a sample size determination problem, the impact of different priors is evaluated.  相似文献   
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Summary.  We explore the determinants of debt, financial assets and net worth at the household level by using survey data for Germany, Great Britain and the USA. To identify which households are potentially vulnerable to adverse changes in the economic environment, we also explore the determinants of a range of measures of financial pressure: the probability that a household has negative net worth; the debt-to-income ratio; mortgage income gearing; the saving-to-income ratio. Our empirical findings suggest that the poorest and the youngest households are the most vulnerable to adverse changes in their financial circumstances.  相似文献   
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With mounting evidence demonstrating the link between child emotion regulation (ER) and emotion socialization, we conducted a longitudinal study to understand (a) emotion-specific trajectories of adolescent ER and (b) how specific parent and friend emotion socialization strategies impact ER over 4 years. Participants were 209 adolescents (52.5% girls; Mage = 12.66 years; 75.7% White) and their parents. Latent growth curve models identified unique trajectories for anger and sadness/worry regulation. Anger regulation increased across time, whereas sadness/worry regulation remained highly stable longitudinally, lacking variance for growth modeling. Friend emotion socialization emerged as a more salient predictor of anger regulation than parent emotion socialization. Friend reward, override, and punish responses predicted initial levels. Friend punish and parent magnify responses predicted the slope.  相似文献   
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