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871.
This study is the first to comprehensively examine the effect of state anti-bullying laws (ABLs) on school safety and youth violence. Using existing data from the Youth Risk Behavior Surveys and the Uniform Crime Reports, and newly-collected data on school shootings, we find little evidence that the typical state ABL is effective in improving school safety and student well-being. However, this null finding masks substantial policy heterogeneity. State mandates that require school districts to implement strong, comprehensive anti-bullying policies are associated with a 7 to 13 % reduction in school violence and an 8 to 12 % reduction in bullying. In addition, our results show that strong anti-bullying policy mandates are associated with a reduction in minor teen school shooting deaths and violent crime arrests, suggesting potentially important spillover effects.  相似文献   
872.
Despite the historical highs for age at first marriage, little is known about the causal relationship between marriage delay and wages, and more importantly, the mechanisms driving such relationship. We attempt to fill the void. Building on an identification strategy proposed in Dahl (Demography 47:689–718, 2010), we first establish the causal wage effects of marriage delay. We then propose ways to distinguish among competing theories and hypotheses, as well as the channels through which marriage delay affects wages. Specifically, we take advantage of their different implications for causal relationship, across gender and sub-populations. We reach two conclusions. First, we find a positive causal impact of marriage delay on wages, with a larger effect for women. Comparison of IV and OLS estimates suggests that the observed relationship between marriage delay and wages is attributed to both selection in late marriages and true causal effects. Second, we find strong evidence that the positive, causal effects are almost exclusively through increased education for both men and women.  相似文献   
873.
We investigate the relationship between economic freedom and international migration for the 1980–2010 period using a dataset on migration from 91 emerging countries to the 20 most attractive OECD destination countries. We find that more economic freedom at home discourages high-skilled migration, but not low-skilled migration. The negative association between economic freedom and high-skilled emigration also holds when we estimate (dynamic) panel models that allow for endogeneity in the economic freedom-migration nexus. In sum, our findings suggest that high-skilled migration is especially responsive to the economic incentives resulting from economic freedom.  相似文献   
874.
This paper stems from the observation that there are two worldwide trends, pension reform and population ageing, and asks whether the two may be related. Exploring the cases of pension reform in different countries, we find that, although they are very different, the cases share a common characteristic: they shift risks away from workers towards those who are retired. Furthermore, population ageing, by increasing the weight of the elderly relative to working generations, raises the price of intergenerational risk sharing. Combining these findings, we argue and show formally that pension reform can be seen as a welfare-best response to population ageing.  相似文献   
875.
876.
Early in the 30-year HIV/AIDS pandemic in Sub-Saharan Africa, epidemiological studies identified formal education attainment as a risk factor: educated Sub-Saharan Africans had a higher risk of contracting HIV/AIDS than their less educated peers. Later demographic research reported that by the mid-1990s the education effect had reversed, and education began to function as a social vaccine. Recent counter-evidence finds a curvilinear pattern, with the association between educational attainment and HIV/AIDS infection changing from positive to negative across the education gradient. To reconcile these inconsistent conclusions, a hypothesis is developed and tested that education at early stages functioned as a risk factor and later functioned (and continues to function) as a social vaccine. We reason that this shift in the direction of the education effect was concurrent with changes in the public health environment in SSA that early on heightened material benefits from educational attainment but later heightened cognitive benefits from schooling. Using the 2003/2004 Demographic Health Surveys from four Sub-Saharan African countries (Cameroon, Ghana, Kenya and Tanzania), we tested this hypothesis (differential effects of schooling) using non-linear regression analysis (probit), identifying the different public health periods and controlling for confounding factors. The results support the hypothesis that the education effect shifted historically in the HIV/AIDS pandemic in SSA as we hypothesized.  相似文献   
877.
878.

Background

Cultural safety in higher education learning and teaching environments is paramount to positive educational outcomes for Aboriginal and/or Torres Strait Islander (hereafter called First Peoples) students. There is a lack of research evaluating the impact of continuing professional development on midwifery academics' awareness of cultural safety.

Aim

To implement and evaluate a continuing professional development intervention to improve midwifery academics' awareness of cultural safety in supporting First Peoples midwifery students success.

Methods

A pre-post intervention mixed methods design was used. Academics (n = 13) teaching into a Bachelor of Midwifery program agreed to participate. The intervention consisted of two workshops and five yarning circles across a semester. Data included the Awareness of Cultural Safety Scale, self-assessment on cultural safety and perceptions of racism, evaluation of the intervention, participants’ journal entries, and researcher’s reflections.

Findings

Responses on the Awareness of Cultural Safety Scale revealed significant improvement in participants’ awareness of cultural safety. There was an upward trend in self-assessment ratings. Participants reported high levels of satisfaction with the intervention or workshops and yarning circles. Participants’ journal entries revealed themes willingness to participate and learn, confidence as well as anger and distress.

Conclusion

Increased awareness of cultural safety can be transformative for midwifery academics. Workshops and yarning circles can support academics in moving beyond a ‘sense of paralysis’ and engage in challenging conversations to transform their learning and teaching and in turn foster a culturally safe learning and teaching environment for First Peoples midwifery students towards success.  相似文献   
879.
880.
The Kidney Exchange Problem (KEP) is a combinatorial optimization problem and has attracted the attention from the community of integer programming/combinatorial optimisation in the past few years. Defined on a directed graph, the KEP has two variations: one concerns cycles only, and the other, cycles as well as chains on the same graph. We call the former a Cardinality Constrained Multi-cycle Problem (CCMcP) and the latter a Cardinality Constrained Cycles and Chains Problem (CCCCP). The cardinality for cycles is restricted in both CCMcP and CCCCP. As for chains, some studies in the literature considered cardinality restrictions, whereas others did not. The CCMcP can be viewed as an Asymmetric Travelling Salesman Problem that does allow subtours, however these subtours are constrained by cardinality, and that it is not necessary to visit all vertices. In existing literature of the KEP, the cardinality constraint for cycles is usually considered to be small (to the best of our knowledge, no more than six). In a CCCCP, each vertex on the directed graph can be included in at most one cycle or chain, but not both. The CCMcP and the CCCCP are interesting and challenging combinatorial optimization problems in their own rights, particularly due to their similarities to some travelling salesman- and vehicle routing-family of problems. In this paper, our main focus is to review the existing mathematical programming models and solution methods in the literature, analyse the performance of these models, and identify future research directions. Further, we propose a polynomial-sized and an exponential-sized mixed-integer linear programming model, discuss a number of stronger constraints for cardinality-infeasible-cycle elimination for the latter, and present some preliminary numerical results.  相似文献   
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