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971.
The survival of the tiger (Panthera tigris) is seriously threatened by poaching to provide raw materials for Traditional Chinese Medicines (TCMs). Most highly prized are the tiger's bones, which are used in combination with other animal and plant derivatives in pills and plasters for the treatment of rheumatism and other ailments. Hundreds of patent remedies have been produced which claim to contain tiger bone, but proof of its presence is needed, if legislation prohibiting the trade in endangered species is to be enforced. A highly sensitive tiger-specific real-time PCR assay has been developed to address this problem. Using primers specific to the tiger mitochondrial cytochrome b gene, successful amplification has been reliably achieved from blood, hair and bone as well as from a range of TCMs spiked with 0.5% tiger bone. Although capable of detecting fewer than 10 substrate molecules, the seven varieties of TCM pills and plasters tested showed no detectable trace of tiger DNA before spiking. Furthermore, sequencing several "tiger bone" fragments seized from TCM shops has shown that they actually originated from cattle and pigs. The potential effects of traditional bone preparation methods, evidence that much lower concentrations are used than alleged on TCM packaging, and substitution of bones from other species all suggest a low likelihood of detecting tiger DNA in patent medicines. Despite this, the basic methods have been thoroughly proven and can be readily applied to derivatives from other CITES protected species providing a rapid and highly sensitive forensic test for species of origin. Potential applications to the monitoring of wild populations are demonstrated by the successful identification of shed hairs and faecal samples.  相似文献   
972.
This work describes the statistical features of a database for two Brazilian populations (one from the Rio de Janeiro State (southeast region), and one from the Mato Grosso do Sul State (central western region) using fourteen short tandem repeat loci (STR).  相似文献   
973.
Endogenous ethanol concentrations in blood were determined by sensitive headspace gas chromatography/mass spectrometry in 1557 residents of the United Arab Emirates. The subjects were from 13 nationalities, of both sexes and of different age groups. There was no significant difference in blood ethanol concentration between nationalities or between sexes within and between nationalities. The data was pooled and the overall median, minimum, maximum, 25% percentile and 75% percentile were 0.04, 0.00, 3.52, 0.01 and 0.09 mg/dl respectively. The values of blood ethanol concentration as reported in this study indicate that they are far too low to have any forensic significance.  相似文献   
974.
This report examines possession and storage of firearms in low-income urban families with at least one child between 8 and 12 years of age. The data primarily consisted of responses to a survey administered to parents, but these data were supplemented by records obtained from discussion groups composed of children between 8 and 12 years of age. The data were collected from five low-income neighborhoods in a medium sized city in the Pacific Northwest as part of a larger study focusing on the presence of risk factors for substance abuse, violence, and gang activity. All five neighborhoods are known to be plagued by poverty, violence, substance abuse, and gang activity. To make our findings more understandable, we compared our findings from these neighborhoods to similar data from a middle-class neighborhood. Middle-class parents were twice as likely to have firearms in their homes, but were much less likely to keep them loaded and/or unlocked. High rates of victimization, fear of crime, self-protective behavior, and exposure to threats or attacks were associated with keeping firearms for protection and engaging in risky gun behavior in the home.  相似文献   
975.
976.
New governance arrangements for NHS Foundation Trusts (FTs) aimed to replace centralized state ownership of acute English hospitals with a new form of social ownership. Under this, trusts would exist as independent public interest organizations on the model of mutuals and co‐operative societies. Assessing the impact of the new arrangements on the management structure of four acute hospitals, we demonstrate that FTs have failed to deliver social ownership and local accountability on this model. We suggest that policy‐makers should re‐frame the governance apparatus associated with mutualism and social ownership in terms of the concept of meta‐regulation. By re‐framing governors as meta‐regulators, regulatory institutions would acquire new powers to steer FTs towards sustainable forms of compliance via non‐coercive, non‐intrusive means.  相似文献   
977.
978.
The paper follows on from earlier work [Taroni F and Aitken CGG. Probabilistic reasoning in the law, Part 1: assessment of probabilities and explanation of the value of DNA evidence. Science & Justice 1998; 38: 165-177]. Different explanations of the value of DNA evidence were presented to students from two schools of forensic science and to members of fifteen laboratories all around the world. The responses were divided into two groups; those which came from a school or laboratory identified as Bayesian and those which came from a school or laboratory identified as non-Bayesian. The paper analyses these responses using a likelihood approach. This approach is more consistent with a Bayesian analysis than one based on a frequentist approach, as was reported by Taroni F and Aitken CGG. [Probabilistic reasoning in the law, Part 1: assessment of probabilities and explanation of the value of DNA evidence] in Science & Justice 1998.  相似文献   
979.
980.
A good deal of research in recent years has revisited the relationship between immigration and violent crime. Various scholars have suggested that, contrary to the claims of the classic Chicago School, large immigrant populations might be associated with lower rather than higher rates of criminal violence. A limitation of the research in this area is that it has been based largely on cross‐sectional analyses for a restricted range of geographic areas. Using time‐series techniques and annual data for metropolitan areas over the 1994–2004 period, we assess the impact of changes in immigration on changes in violent crime rates. The findings of multivariate analyses indicate that violent crime rates tended to decrease as metropolitan areas experienced gains in their concentration of immigrants. This inverse relationship is especially robust for the offense of robbery. Overall, our results support the hypothesis that the broad reductions in violent crime during recent years are partially attributable to increases in immigration.  相似文献   
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