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231.
A high plasma concentration of total homocysteine (tHcy) and a deficiency of vitamins related to its metabolism, such as vitamin B12 and folate, have been associated with cardiovascular disease. Postmenopausal women have higher concentrations than age-matched premenopausal women, and plasma concentrations of homocysteine in postmenopausal women taking hormone replacement therapy are significantly lower than they are in those who do not take estrogen supplements. Because of the possible mixed effects of HRT on cardiovascular events, surrogate end-points must be evaluated with caution. While measuring homocysteine levels is relatively simple, evidence from well designed trials is awaited before population screening can be advocated. Also, the benefits of reducing homocysteine levels with folic acid and vitamin B6 and B12 supplements are highly debated.  相似文献   
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The paper is based on a survey of graduates of the BA course Social Sciences at the Heinrich-Heine-University Düsseldorf. The course, which is a combination of Sociology, Political Science and Communication and Media Studies, was set up in 1999. In 2002 the first students completed the course. Therefore, the BA course Social Sciences is one of the BA courses with the longest experience in Germany. Four graduate years were interviewed for the survey. The aim of the survey was to find out where the graduates now stand and how they judge the course in retrospect. The results show that half of the graduates currently have an occupation, slightly over a third is doing a Master’s degree and about 10 % are in a temporary situation or performing other activities. Overall, the graduates are satisfied with the course. The evaluation of the individual course elements shows the strengths and weaknesses of the course.  相似文献   
233.
Young men who have sex with men (YMSM), particularly Black YMSM, bear a disproportionate burden of new human immunodeficiency virus (HIV) infections in the United States. Several studies support the positive and protective role of religion in health and the prevention of morbidity and mortality. However, little empirical research has been conducted looking at religion with the context of YMSM and HIV prevention. We examined the impact of religious attendance and faithfulness on sexual risk among a community-based sample of 450 YMSM in Chicago ages 16 to 20. Participants were mostly racial/ethnic minorities, that is, Black (53.4%) and Latino (19.9%). Multivariate logistic regression indicated that faithfulness in combination with frequent formal religious attendance was associated with a decrease in reported number of unprotected anal sex acts, including unprotected receptive anal sex with male partners. These association trends were also found for the Black YMSM in our sample, suggesting that religious involvement and faithfulness is a potential protective factor for the acquisition of HIV among this high-risk population.  相似文献   
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What are the explaining factors for the wave of riots in France in November 2005? In providing some answers, this article begins by examining the practical usefulness of the French republican model of integration for social cohesion, highlighting the way its negation of other criteria, such as ethnicity, race, or religion, limit this national conception of citizenship and emphasizing these excluded factors as one of the main causes of frustration and resentment among migrant groups in France.The author compares these riots to the student movements in spring 2006 and shows some similarities as well as important differences between the explaining structural factors of these two youth-based social upheavals. One of the contributing distinctions is the experience of ethnic and racial discrimination as an important source of deep resentment. The author avoids reducing the riots simply to a clash between ethnic groups with specific ethnic interests or a class revolt. Instead, he stresses the relationship between specific social structural factors and spatial effects as the element that created the context for the riots by transforming inequalities into visible and indefensible discrimination. Several factors show that spatial aspects (in the form of segregation) are important alongside the ethnic/racial ones in explaining the riots.  相似文献   
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In this paper we derive an explicit model of negotiations between spouses when unconstrained transfers are possible only in case of separation. We show that inefficient separation may occur in equilibrium even under consensual divorce law. This provides theoretical support for the view that changes in social norms rather than in legislation may be responsible for increasing divorce rates. (JEL: C78, J120)  相似文献   
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In this paper we define a finite mixture of quantile and M-quantile regression models for heterogeneous and /or for dependent/clustered data. Components of the finite mixture represent clusters of individuals with homogeneous values of model parameters. For its flexibility and ease of estimation, the proposed approaches can be extended to random coefficients with a higher dimension than the simple random intercept case. Estimation of model parameters is obtained through maximum likelihood, by implementing an EM-type algorithm. The standard error estimates for model parameters are obtained using the inverse of the observed information matrix, derived through the Oakes (J R Stat Soc Ser B 61:479–482, 1999) formula in the M-quantile setting, and through nonparametric bootstrap in the quantile case. We present a large scale simulation study to analyse the practical behaviour of the proposed model and to evaluate the empirical performance of the proposed standard error estimates for model parameters. We considered a variety of empirical settings in both the random intercept and the random coefficient case. The proposed modelling approaches are also applied to two well-known datasets which give further insights on their empirical behaviour.  相似文献   
240.
We discuss using the presumed ‘wisdom of the crowd’ to reduce the bullwhip effect in supply chains by enhancing the accuracy of demand forecast. Our case study describes a joint project of a leading European technology company (We chose RAGD as a pseudonym for the company throughout the study.) and the University of Kassel on a smartphone application for end customers to gather early information for this producer’s forecast. Our results confirm the ‘wisdom of the crowd’ hypothesis: A group of experts, in our case technicians who install and maintain RAGD-products, is capable of anticipating market fluctuations six weeks in advance. This only holds true if the ‘crowd’ of technicians is large enough. Our business climate index outperforms the company forecast in the first six months, when on average 22 technicians took part per week. We discuss successes and limitations of the cooperation and provide recommendations for similar projects.  相似文献   
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