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Comparative sequencing of cannabis individuals across 12 chloroplast and mitochondrial DNA loci revealed 7 polymorphic sites, including 5 length variable regions and 2 single nucleotide polymorphisms. Simple PCR assays were developed to assay these polymorphisms, and organelle DNA haplotypes were obtained for 188 cannabis individuals from 76 separate populations, including drug-type, fibre-type and wild populations. The haplotype data were analysed using parsimony, UPGMA and neighbour joining methods. Three haplotype groups were recovered by each analysis method, and these groups are suggestive of the crop-use characteristics and geographical origin of the populations, although not strictly diagnostic. We discuss the relationship between our haplotype data and taxonomic opinions of cannabis, and the implications of organelle DNA haplotyping to forensic investigations of cannabis.  相似文献   
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No computation is performed more frequently by forensic toxicologists than that involving Widmark's equation. The equation is employed to estimate either the number of drinks consumed or the corresponding blood or breath alcohol concentration. Despite the wide use of Widmark's equation, rarely is an uncertainty estimate also provided. Estimates from Widmark's equation involve at least seven uncertain random variables. Uncertainty estimates are presented that rely on methods of general error propagation compared to a method developed by Widmark. Assuming reasonable variable and uncertainty estimates, the error propagation method yielded for N=10.4 drinks, a combined uncertainty (standard deviation) of 1.3 drinks (CV=12.3%). Similarly, estimating the blood alcohol concentration yielded for 0.120 g/100 ml, an uncertainty of 0.0255 g/100 ml (CV=21.2%). Widmark's uncertainty method yielded 1.6 drinks (CV=15.4%). The derivation of Widmark's uncertainty estimate is also presented, showing that he considered only rho and beta to be uncertain. Widmark estimates for the number of drinks should include a 2CV estimate of approximately 25% while the blood alcohol concentration estimate should include a 2CV estimate of approximately 42%. Including valid estimates of uncertainty should enhance the legal admissibility and confidence for Widmark estimations.  相似文献   
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Immigrants are blamed for economic and social problems throughout Europe. This article explores the theoretical argument that electorates support new right parties because they are placing more emphasis on specific issues like immigration. The findings provide evidence that immigration explains much of the electoral support for the new right parties in Germany. Areas with larger immigrant populations provide fewer votes, while areas where immigrants ‘commit more crime’ provide greater support. This suggests the problems associated with immigration explain the new right's support, rather than simple xenophobia. As long as such problems continue, the potential for new right success will remain.  相似文献   
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A developmental validation study based on recommendations of the Scientific Working Group on DNA Analysis Methods (SWGDAM) was conducted on a multiplex system of 10 Cannabis sativa short tandem repeat loci. Amplification of the loci in four multiplex reactions was tested across DNA from dried root, stem, and leaf sources, and DNA from fresh, frozen, and dried leaf tissue with a template DNA range of 10.0-0.01 ng. The loci were amplified and scored consistently for all DNA sources when DNA template was in the range of 10.0-1.0 ng. Some allelic dropout and PCR failure occurred in reactions with lower template DNA amounts. Overall, amplification was best using 10.0 ng of template DNA from dried leaf tissue indicating that this is the optimal source material. Cross species amplification was observed in Humulus lupulus for three loci but there was no allelic overlap. This is the first study following SWGDAM validation guidelines to validate short tandem repeat markers for forensic use in plants.  相似文献   
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The study assesses the impact of a theory-based school violence program though a survey of 1,500 middle and high school students. It is the first to apply the concept of optimistic bias within the school violence context. Despite high profile school shootings, the students maintained the belief that violence was less likely to happen to them (personally) or in their schools than elsewhere in the country. Findings indicate that optimistic bias can be reduced through educational campaigns, and suggest a means of reducing violence by first reducing optimistic bias.  相似文献   
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