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71.
The authors examine the characteristics of threatening and otherwise inappropriate communications sent to members of the U.S. Congress by a sample of 86 subjects, 20 of whom threatened assassination. We quote excerpts from these letters and provide quantitative data on such variables as the volume, duration, form, and appearance of such communications; the enclosures; the subjects' perceived relationships to the recipients; the thematic content of the communications; and the messages and threats communicated. Comparisons between 43 subjects who pursued encounters with members of Congress and 43 who did not revealed 17 factors associated with such pursuit. In this population, threateners were significantly less likely to pursue an encounter than inappropriate letter writers who did not threaten, regardless of the type of threat or the harm threatened. Inappropriate letters to members of Congress are compared with those directed to Hollywood celebrities. Mentally disordered persons writing to public figures often mention and sometimes threaten public figures other than those to whom the letters are addressed, which raises important issues regarding notification of endangered third parties and the sharing of information among protective agencies.  相似文献   
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Sixteen major evaluations of programs to prevent school bullying, conducted in 11 different countries, are reviewed in detail. Of these 16 evaluations, 8 produced desirable results, 2 produced mixed results, 4 produced small or negligible effects, and 2 produced undesirable results. These varying findings may reflect variations in programs, in implementation, in assessment methods, or in evaluation designs. It is concluded that high-quality evaluations are needed in the future, with randomized designs, theoretically grounded interventions, multiple measures of bullying, and attempts to disentangle the effectiveness of different program components.  相似文献   
74.
A 6-month-old girl died suddenly without any previous symptoms of heart failure. Autopsy examination showed cardiomegaly (97 g) with a severely fibrotized myocardium. The left coronary artery was originating from the pulmonary artery. Histologically, the myocardium showed myocardial infarcts of different ages, as well as grossly thickened arterial branches due to increased flow in left-right shunt. We suggest that rare anomalies of the coronary arteries should be considered in the autopsies of suspected sudden infant death syndrome cases.  相似文献   
75.
We specify an individual-level model linking crime desistance to estimates of legal risk, differential expectations, degree of past success at legitimate and criminal pursuits, and age. OLS and logistic regression procedures are used to estimate the model using longitudinal data on serious, previously imprisoned offenders. As predicted, age decreases estimates of the likely payoffs from crime and legitimate employment. Contrary to predictions, age is unrelated to the perceived legal risk of renewed criminal participation. Age, past success at avoiding confinement, expectations of success from crime, and level of education are significant predictors of crime desistance. Neither the perceived legal risk of crime nor expectations of success through straight pursuits significantly predict desistance. We suggest an interpretation for these anomalous findings.  相似文献   
76.
The impact of high temperatures (24 to 39 degrees C) and low to moderately high humidities (20 to 70%) on the applicability of TLC systems for drug identification was studied during a 6 month climatologic cycle in Burkina Faso (West Africa). In general, the Rf values as observed on the plates were found to be substantially affected as compared with values obtained at temperate climates. Some TLC systems were more affected than others and the largest deviations of up to 30 Rf units were at low humidities. Tropical conditions also had a negative effect on the reproducibility of Rf values. However, when an Rf-correction procedure was applied, using reference mixtures of known drugs on each plate, accuracy as well as reproducibility of the resulting Rfc values were drastically improved and data thus corrected were found to be compatible with existing TLC data bases developed under moderate climatological conditions. The impact of high to extremely high humidities (70 to 100%) remains to be investigated.  相似文献   
77.
Following the tradition of Joan McCord's work, this paper reviews longitudinal-experimental studies in criminology with community samples of at least 100 persons, follow-up periods of at least 5 years, personal interviews, and measures of offending. The main advantages of such studies are in investigating both the natural history of development (including the effects of risk/protective factors and life events) and the impact of interventions on offending. This paper also reviews advantages and problems of prospective longitudinal surveys, randomized experiments, and longitudinal-experimental studies in criminology. Four key longitudinal-experimental studies were conducted by Joan McCord, Richard Tremblay, Lawrence Schweinhart and David Olds. Other studies have been conducted, or are currently under way, but no criminological study has yet been published with several years of personal data on participants both before and after an intervention.Joan McCord Award Lecture given at the American Society of Criminology, Toronto, Canada.  相似文献   
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The link between resource deprivation and urban violence has long been explored in criminological research. Studies, however, have largely ignored the potential for resource deprivation in particular communities to affect rates of violence in others. The relative inattention is notable because of the strong theoretical grounds to anticipate influences that extend both to geographically contiguous areas and to those that, though not contiguous, share similar social characteristics. We argue that such influences—what we term spatial and social proximity effects, respectively—constitute a central feature of community dynamics. To support this argument, we develop and test theoretically derived hypotheses about spatial and social proximity effects of resource deprivation on aggregated and disaggregated homicide counts. Our analyses indicate that local area resource deprivation contributes to violence in socially proximate communities, an effect that, in the case of instrumental homicides, is stronger when such communities are spatially proximate. We conclude by discussing the implications of our findings for theories focused on community‐level social processes and violence, and for policies aimed at reducing crime in disadvantaged areas.  相似文献   
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