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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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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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In recent years, there has been a substantial increase in the literature on the relationship between politics and mass media, mainly in discrete topic areas such as the impact of mass media on electoral behaviour, the emergence of new forms of political communication, or media political economy. At the same time, this diverse literature has often focused on a single general issue, typically characterised in terms of the 'transformation' of politics. Despite this common theme, there has been relatively little attempt to connect and compare the different approaches. Looking at the theoretical differences in the new literature on politics and mass media reveals three perspectives – pluralist, constructivist, and structuralist. These approaches have too often tacitly co-existed, instead of more competitively striving to advance knowledge in the three main topic areas above.  相似文献   
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Fibres used in forensic casework suffer from a disadvantage common to other forms of trace evidence--it is not possible to state with absolute certainty that they originate from a specific source. Target fibre studies, population studies and research on 'blocks of colour' have effectively demonstrated the polymorphism of textile fibres (particularly man-made ones) and have shown that when a fibre is believed to have a specific putative source, the chance that it has originated from a different source purely by coincidence is extremely remote. A study by Houck MM (Houck MM, Inter-comparison of unrelated fibre evidence. Forensic Science International 2003; 135: 146-149) has shown that no coincidental matching fibres were recovered from items of clothing examined in 20 unrelated crimes. The study involved over two million comparisons. This work goes a step further, and using the example of blue polyester fibres shows that even within a very narrow segment of the whole general fibre population, many examples of a specific colour/type of man-made fibre taken from random sources can be compared and the chance of any two being the same is very low. These studies should help to show the specificity and value of transferred fibres in providing forensic evidence.  相似文献   
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