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31.
Subject attrition is a potentially serious threat to the validity of inferences drawn from panel studies of delinquency and drug use. Prior assessments of this issue produce somewhat conflicting results, with some finding that respondents who leave the panel have higher rates of delinquency and drug use than those who remain, while other studies report little or no differential attrition. Despite these findings, there has been virtually no examination of the extent to which respondent attrition can bias substantive findings in panel studies of delinquency and drug use. The present article addresses this issue by simulating higher levels of attrition in an ongoing panel study that has a low rate of attrition and little differential attrition. It finds that failure to include more elusive respondents (those who are more mobile) would bias estimates of prevalence and frequency of delinquency and drug use as well as results from basic regression analyses. Failure to include less cooperative respondents (those who require more contacts) produces similar, but somewhat smaller, differences. The methodological implications of the results are discussed.  相似文献   
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The aim of the present investigations was to find markers for differentiating between the consumption of illegal cannabis products and legal medication containing fully synthetic Δ9-tetrahydrocannabinol (Δ9-THC), e.g., Marinol capsules. Δ9-Tetrahydrocannabinolic acid A (Δ9-THCA-A) and Δ9-tetrahydrocannabivarinic acid A (Δ9-THCVA-A) were taken into consideration for analysis, because these substances are the precursors of Δ9-THC and Δ9-tetrahydrocannabivarin (Δ9-THCV) in plant material of Cannabis sativa and are not contained in medical THC formulations. Whereas Δ9-THCA-A is an already well investigated substance, there is little analytical data on Δ9-THCVA-A. The reason for the presented investigations was a case in which a man was tested positive for Δ9-THC during a routine traffic control claiming that the positive serum sample resulted from the intake of a THC medication (Marinol) and not from consuming illegal cannabis products. Sample preparation consisted of a protein precipitation with acetonitrile. Analysis was carried out on a Thermo Fisher LCQ Deca ion trap LC-MS-MS-system using electron spray ionization (ESI) in negative mode. MS(2)- and MS(3)-full scan spectra were recorded for Δ9-THCA-A and Δ9-THCVA-A starting from [M-H](-). Reference spectra were obtained by measuring a Δ9-THCA-A reference solution and an ethanolic cannabis extract for Δ9-THCVA-A as there is no reference material for this cannabinoid available on the market yet. Main transitions for Δ9-THCA-A were m/z 357→313 and 339 in the MS(2)-spectrum and m/z 313→245 and 191 in the MS(3)-spectrum. Fragmentation pattern of Δ9-THCVA-A was identical with a difference of 28 amu less for the precursor ion as well as the fragments due to a shorter alkyl side chain in the molecule (MS(2): m/z 329→285 and 311; MS(3): m/z 285→217 and 163). The two plant cannabinoids Δ9-THCA-A and Δ9-THCVA-A could be detected in the serum sample by LC-MS-MS which proved the intake of illegal cannabis products derived from plant material of C. sativa in the described case.  相似文献   
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Lophophora williamsii (peyote) is a small, spineless, greenish‐blue cactus found in Mexico and the southwestern United States. Ingestion of the cactus can result in hallucinations due to its content of mescaline. In the United States, L. williamsii is classified as a Schedule I controlled substance. In this study, we use DNA analysis of the chloroplast trnL/trnF region and chloroplast rbcL gene to identify the individuals of Lophophora. Using the rbcL gene, Lophophora specimens could be distinguished from outgroups, but species within the genus could not be distinguished. The trnL/trnF region split the Lophophora genus into several groups based on the length and substructure of an AT‐rich segment of the sequence. Our results indicate that the genetic variability at the trnL/trnF locus is greater than previously recognized. Although DNA structures at the trnL/trnF region and rbcL gene do not align with the classification of Lophophora species, they can be used to aid in forensic analysis.  相似文献   
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Eleven deaths from crocodile attacks in the Northern Territory, Australia were reviewed. The male:female ratio was 8:3; age range—10–62 years, average 29.4 years. Four children were included (one boy and three girls, aged 10, 11, and two at 12 years), and there were seven aboriginal victims (64%). The attacks were witnessed in eight cases with the victims swimming in freshwater N = 5, standing on a river bank N = 1, fishing in fresh water N = 1, or diving in the sea N = 1. At autopsy, several distinct patterns of injury were observed ranging from complete traumatic disruption of the body with only incomplete remains for examination (N = 5), to crushing of the head with fractures of the skull (N = 4), crushing of the chest with fractures of the ribs and sternum (N = 2), and avulsion of limbs (N = 4). In one case, there was decapitation. Autopsy evaluations were complicated by decomposition and loss of body parts.  相似文献   
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The purpose of this essay is to highlight the fact that certain specific governing or guideline criteria are in fact necessary before one can establish cases in which it would be admissible to treat the genders unequally. Those criteria, insofar as women's rights are concerned, consist of the need to overcome a situation of inequality which arises due to cultural and social reasons. An analysis of the different types of feminist movements follows, concluding that feminism implies two types of hypotheses. On one level feminism can be said to be a theory for equality; on another level it is a theory which turns around the objectivity of law, although it does, in both cases, challenge classical political and iudicial theses.  相似文献   
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Abstract

A recent British Prison Service initiative has focused on providing sex offender programmes facilitated by multi-disciplinary teams of staff. A three week long training programme was designed to provide staff with the necessary knowledge, skills and experience to facilitate these structured treatment groups. Following the training, staff indicated they were more confident in their ability to provide treatment and showed a greater belief that treatment could be successful. In addition, they showed significantly more positive attitudes towards sexual offenders and to offenders in general. However, participants did not indicate undue concern about working in a sensitive treatment area. This pattern continued at six month follow-up, indicating that the training changed attitudes as expected, and that the training was seen by participants as adequately preparing them to undertake provision of a structured sex offender treatment programme in a secure setting.  相似文献   
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