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The North American Free Trade Agreement (NAFTA) and the General Agreement on Tariffs and Trade (GATT) have focused attention on risk assessment of potential insect, weed, and animal pests and diseases of livestock. These risks have traditionally been addressed through quarantine protocols ranging from limits on the geographical areas from which a product may originate, postharvest disinfestation procedures like fumigation, and inspections at points of export and import, to outright bans. To ensure that plant and animal protection measures are not used as nontariff trade barriers, GATT and NAFTA require pest risk analysis (PRA) to support quarantine decisions. The increased emphasis on PRA has spurred multiple efforts at the national and international level to design frameworks for the conduct of these analyses. As approaches to pest risk analysis proliferate, and the importance of the analyses grows, concerns have arisen about the scientific and technical conduct of pest risk analysis. In January of 1997, the Harvard Center for Risk Analysis (HCRA) held an invitation-only workshop in Washington, D.C. to bring experts in risk analysis and pest characterization together to develop general principles for pest risk analysis. Workshop participants examined current frameworks for PRA, discussed strengths and weaknesses of the approaches, and formulated principles, based on years of experience with risk analysis in other setting and knowledge of the issues specific to analysis of pests. The principles developed highlight the both the similarities of pest risk analysis to other forms of risk analysis, and its unique attributes.  相似文献   
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The relationship between refugee investments in human capital and short-run economic outcomes may influence the extent to which refugees invest in human capital that is associated with positive future economic mobility. Using data from the Annual Survey of Refugees from 2016 and 2017 we assess the relationship between recent investments in human capital and hourly wages for employed refugees in the United States. Results suggest that recent job training has a positive effect on hourly wages. In contrast, enrollment in English classes and educational programmes have no short-term positive effects on hourly wages. When combined with the pressure resettled refugees experience to find employment quickly, these results suggest that the lack of short-term wage benefits from English language or educational courses may dissuade refugees from sufficiently investing in the amount of English language or education necessary to promote positive long-term economic mobility.  相似文献   
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Parenting styles associated with maternal depression are a risk factor for adolescent psychopathology, and maternal attributional styles may be a key mechanism in this relationship. Mother-adolescent dyads (N = 180; 96 male; ages 10–15) completed in-person interactions and then the mothers participated in a video-mediated recall procedure to assess maternal attributions. Maternal depression was associated with negative attributions. Negative attributions were associated with low parental acceptance, aggressive parenting, and low positive parenting. Positive maternal attributions were associated with less aggressive parenting, and more positive parenting during one interaction task. Adolescent externalizing behaviors were associated with negative attributions. Future research should evaluate whether maternal attributions mediate the association between maternal depression and both parenting behaviors and adolescent mental health.  相似文献   
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A new test statistic based on runs of weighted deviations is introduced. Its use for observations sampled from independent normal distributions is worked out in detail. It supplements the classic χ2 test which ignores the ordering of observations and provides additional sensitivity to local deviations from expectations. The exact distribution of the statistic in the non-parametric case is derived and an algorithm to compute p-values is presented. The computational complexity of the algorithm is derived employing a novel identity for integer partitions.  相似文献   
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The purpose of this paper is to examine how environmental attitudes and concern about water scarcity translate into water conservation behavior. The study considers whether Oregonians environmental concern measured by the New Environmental Paradigm scale and sociodemographic characteristics influence personal water conservation activities. Using a survey conducted in the spring of 2010 of Oregon residents, the interaction of environmental concern and sociodemographics that predict identified water conservation behaviors are considered.  相似文献   
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The aim of this paper is to ascertain the impact of quasi-markets on contracting processes and factors affecting the costs of contracting in Finnish health care in the specific case of laboratory services. By means of a comparative case analysis, we ascertained the changes in organizational contracting practices and identified the actions affecting the transaction costs of contracting in the case of an autonomous municipal enterprise laboratory compared with the same laboratory as a hierarchically run municipal unit. The research was conducted during the years 2007–2011. The results suggest that introducing quasi-markets into laboratory services increased the cost factors of contracting; and had a negative impact on the laboratories’ willingness to create new market relationships.  相似文献   
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BackgroundYoung pregnant women who continue a pregnancy are primarily from a socioeconomically deprived background. The risk factors associated with low socio-economic status may independently affect perinatal and neonatal morbidity to a greater extent than the young age of the woman. Young pregnant women are frequently sceptical about health care providers who they can perceive to be judgemental. This may lead to late booking for pregnancy care, attending few appointments, or not attending the health service for any antenatal care.QuestionDoes the way maternity care is provided affect maternal and neonatal outcomes for young women?MethodA systematic search of the major health databases.ResultsNine research articles met the eligibility criteria: one randomised controlled trial, three prospective cohort studies, two comparative studies with concurrent controls, two comparative studies with historical controls, and one case series.DiscussionProviding young women with a non-standard model of maternity care has some beneficial and no known detrimental effects on childbirth outcomes. While there is a dearth of evidence on the effectiveness of a Midwifery Group Practice model of care for young women, there is strong evidence to suggest that a Group Antenatal Care model increases antenatal visit attendance and breastfeeding initiation, and decreases the risk of preterm birth. There is research to indicate that a Young Women's Clinic model may also increase antenatal visit attendance and decrease the incidence of preterm birth.ConclusionMore well-designed and resourced midwifery models of care for young women should be implemented and rigorously researched.  相似文献   
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