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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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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 tragedy of September 11 highlights the stark contrast between the real and measurable capabilities possessed by one state, and the almost inevitable resentments which the possession of those capabilities engendered in others. The purpose of this article is not to interrogate the strengths and weaknesses of arguments of American decline. Nor is it to speculate at length about September 11th. It is instead to set the scene and try and identify the underlying causes of America's transition from presumed crisis in the 1970s and 1980s to new self-confidence in the 1990s—a self-confidence that some now feel has been shattered by the events of September. While there were important structural reasons why the United States was unlikely to go the way of other powers, it was a peculiar conjuncture of mainly unforeseen developments that combined together after 1989 to improve the U.S. position within the world. We will then move on to discuss the most effective way of characterizing this position. Here, we will mount a defense of the somewhat contentious notion of "hegemony" While recognizing the problems associated with the idea, it will be argued that as a concept it has serious intellectual advantages over its various theoretical competitors. If nothing else, because it focuses on the American role within the world system, rather than just its statically defined position, it is theoretically more suggestive than the less dynamic idea of unipolarity.  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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