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Given that one of the most powerful predictors of adult crime is the presence of behavior problems in childhood and adolescence, there is a need to further understand factors that determine behavior patterns during this developmental stage. This study focuses on stressful life experiences such as exposure to delinquent peers, racial discrimination, as well as family characteristics such as parenting style and family transitions. Data come from four waves of the Family and Community Health Survey, an African-American sample. The present study investigates 354 males from this dataset. We utilize a group-based trajectory model to estimate the number and type of trajectories of delinquency. We then estimate multinomial regression models to predict trajectory group membership. The results indicated that there were four distinct groups of offenders (negligible delinquents; early starter/declining; late starter; and early starter/chronic offenders). We predicted group membership using both early predictors and measures of change in these predictors across the study period. The results indicated that individuals who experience greater racial discrimination (both early in childhood and throughout adolescence) are more likely to be in trajectory groups that begin offending early and persist through adolescence. Additionally, those respondents who reported having friends with greater delinquent behavior were more likely to be in groups that began their offending early in life and persisted when compared to groups who started later or desisted as they entered adulthood. The results contribute to developmental research and provide information that may be helpful in preventing adolescents from persisting in antisocial behavior as they enter adulthood.  相似文献   
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Commercial fisheries represent a significant anthropogenic threat to marine mammal survival. Causes of marine mammal mortality are commonly determined by detailed necropsies of stranded carcasses. Gross evidence of entanglement in a fishery might include gear attached to the body, internal indications of asphyxiation and trauma, or gear markings on the epidermis. As gear is often fishery-specific, wound patterns on the epidermis that are created by entanglements in fishing gear may serve to identify possible sources of mortality. For this study, tools within the Environmental Systems Research Institute, Inc. (ESRI) ArcMap GIS software were used to create maps that outline impressions that fishing gear can leave on the epidermis of entangled marine mammals. These maps can subsequently be used to identify possible sources of fishery entanglement for the many marine mammals that wash ashore without gear attached to their carcass. Entanglement wound patterns can be visually compared with fishing gear characteristics; however, differences in scale and image quality can introduce subjectivity that might hinder source identification. The technique described herein provides an objective way to outline the unique characteristics of fishing gear and their associated wounds on entangled marine mammals. Additionally, spatial relationships are preserved as the maps are adjusted to varying scales. Whereas the initial protocol required time-consuming digitization of the outline and visual determination of the pattern interface, this new, semiautomated technique saves analyst effort and minimizes error.  相似文献   
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Biomedical research, no matter how well designed and ethically conducted, carries uncertainties and exposes participants to risk of injury. Research injuries can range from the relatively minor to those that result in hospitalization, permanent disability, or even death. Participants might also suffer a range of economic harms related to their injuries. Unlike the vast majority of developed countries, which have implemented no-fault compensation systems, the United States continues to rely on the tort system to compensate injured research participants—an approach that is no longer morally defensible. Despite decades of US advisory panels advocating for no-fault compensation, little progress has been made. Accordingly, this article proposes a novel and necessary no-fault compensation system, grounded in the ethical notion of compensatory justice. This first-of-its-kind concrete proposal aims to treat like cases alike, offer fair compensation, and disburse compensation with maximum efficiency and minimum administrative cost. It also harmonizes national and international approaches—an increasingly important goal as research becomes more globalized, multi-site trials grow in number, and institutions and sponsors in the United States move to single-IRB review.  相似文献   
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The paper examines the effects and significance of geographic position, cumulative advantages and disadvantages of past development, present investment cuts, political factors and links, and two recent decrees on enterprises, regional self-management, and the devolution of authority in selected Slavic regions. It argues that structural and spatial constraints and system-preserving controls on the reforms themselves have rendered perestroyka ineffectual and accentuated “center-periphery” tensions within the Slavic republics, Journal of Economic Literature, Classification Numbers: 052, 124, 940.  相似文献   
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A 33-year-old female collapsed and died suddenly after presenting with acute dyspnea and increasing cough over the preceding several months. Autopsy revealed poorly differentiated linitis plastica adenocarcinoma of the stomach. Microscopic examination of the lungs showed features consistent with pulmonary tumor thrombotic microangiopathy (PTTM). PTTM is a well-described complication in patients with adenocarcinoma. The typical presentation involves acute pulmonary hypertension, right-sided heart failure, and sudden death, often before the adenocarcinoma is discovered. The pathophysiology of PTTM remains elusive; it has been suggested that carcinoma cells may produce substances that influence pulmonary vasculature. Our patient had classic clinical and histologic features of PTTM in addition to prominent extravascular compression by intralymphatic tumor cells. These features undoubtedly caused her precipitous decline and lethal pulmonary hypertension, induced by underlying adenocarcinoma. This case demonstrates that sudden death can occur from pulmonary hypertension induced by metastatic carcinoma with remarkably little prior symptomatology.  相似文献   
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