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This study aimed to expand the scope of previous research by assessing the effectiveness of soot-removal techniques on glass from petrol-bomb debris using methods of 1% and 2% sodium hydroxide (NaOH) solutions, ultrasonic bath and vacuum suction. Of particular interest were the 1% and 2% NaOH solutions applied to the soot-covered surfaces. Petrol bombs containing petrol or a 50:50 mix of petrol and motor oil were exploded and the debris was collected for analysis. Favourable results were found to varying degrees using each of the soot-removal methods with the 1% and 2% NaOH wash solutions, being the most useful. The 2% NaOH solution also proved successful as a soak to loosen and remove heavy contamination of soot and accelerants without damaging the finger mark beneath. This study also found that recovery of finger marks in blood from beneath soot using the 2% NaOH solution was possible. Finger marks were also applied to glass bottles with plastic adhesive labels, and providing the fire damage is not too great marks were also retrievable. Results from this study lead to the conclusion that the NaOH wash solution is ideally suited for soot removal to reveal latent and blood-contaminated marks both within the laboratory and at crime scenes.  相似文献   
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This paper investigates whether an Okun-type relationship between output and unemployment is taking hold in formerly planned economies as they move towards the market. Using a first-differences variant of Okun's Law, we test for its presence in 25 transition countries divided into groups of ``reform leaders'' and ``reform laggards.'' For leaders, represented by the 10 European Union (EU) accession countries, Okun's Law is detected in both 1991–94 and 1995–2000 periods. For laggards, represented by the remaining group, it is present only for the later period and only when countries affected by wars are removed from the sample. A comparison of unemployment–output elasticities and unemployment levels in EU candidates and EU members themselves indicates that their labor markets might be converging.  相似文献   
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Community-based delinquency prevention programs, designed to work with youth and families before they become involved with the official court process, are relatively rare. Likewise, few studies have been published concerninge valuative research on such programs. This article reviews some background on program concepts, describes the operations of the Oakland County Probate Court Youth Assistance casework services program, and reports the results of a comprehensive program evaluation project. The findings suggest that prevention programming is one effective strategy to aid in reducing the likelihood of more costly court interventions. Recommendations for program development are offered.  相似文献   
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The lungs of 79 children who had died between the ages of 1 week and 2 years old were histologically examined. 59 of these children could be categorized as cases of Sudden Infant Death because of the history and postmortem findings. In the remaining 20 cases a definite cause of death could be established. This is the same collective on which the histological investigations of the lymphatic tissue has been carried out. Morphological changes which are typical for a virus pneumonia were found in a substantially higher frequency in the cases of Sudden Infant Death than in the control cases. The validity of these findings and their possible significance for the cause of death are discussed.  相似文献   
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The conventional wisdom in criminology is that adult onset of offending is a rare event. Closer examination of the extant literature that use official records, however, reveals that an average of 50 percent of adult offenders initiate offending at age eighteen or older. Although criminological research has investigated late onset offending in adolescence, there is little research on adult onset offending and the correlates of adult offending. Using police contact and interview data from the 1942 and 1949 birth cohort data from Racine, WI, this study investigated the correlates of crime for adult onset and persistent offenders. The results show that employment is the only correlate to affect the probability of adult offending differently for previously delinquent and nondelinquent offenders. This article concludes by highlighting the neglect of research on adult offenders, specifically the large percentage of adult onset offenders, and calling for more research on this topic.  相似文献   
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