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491.
Amplified fragment length polymorphism (AFLP) analysis of botanical forensic evidence provides a means of obtaining a reproducible DNA profile in a relatively short period of time in species for which no sequence information is available. AFLP profiles were obtained for 40 Acer rubrum trees. Leaf material from five additional species was also typed. Genomic DNA was isolated using the DNeasy Plant Miniprep Kit (Qiagen, Valencia, CA), double-digested by two restriction endonucleases (EcoRI and MseI) and ligated to oligonucleotide adapters. Two consecutive PCR reactions (pre-amplification and selective amplification) were performed using a modification of the AFLP protocol described by Gibco (Invitrogen, Rockville, MD). The DNA fragments were separated by capillary electrophoresis using the CEQ 8000 DNA Fragment Analyzer. A number of Acer rubrum species-specific peaks were identified. In addition, within this closed set of samples, 15 of 16 (93.8%) blind samples were correctly identified. AFLP data can be used to determine the species of botanical evidence or to associate a sample to a source. This information can be used in forensic investigations to link a piece of evidence with a particular location or suspect. 相似文献
492.
Allele frequencies for 27 Y-STR loci with U.S. Caucasian, African American, and Hispanic samples 总被引:4,自引:0,他引:4
A total of 263 U.S. Caucasians, 260 African Americans and 140 U.S. Hispanics or a subset of 31 Caucasians, 32 African Americans, and 32 Hispanics were typed for 27 Y-chromosome short tandem repeat (Y-STR) markers: DYS444, DYS446, DYS449, DYS463, DYS485, DYS490, DYS495, DYS504, DYS505, DYS508, DYS520, DYS522, DYS525, DYS532, DYS533, DYS534, DYS540, DYS556, DYS557, DYS570, DYS575, DYS576, DYS594, DYS632, DYS635, DYS641, and DYS643. Allele frequencies for each locus are reported along with nomenclature based on sequence analysis. 相似文献
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494.
Longitudinal relations between past suicidality and subsequent changes in psychological distress at follow-up were examined among gay, lesbian, and bisexual (GLB) youths, as were psychosocial factors (e.g., self-esteem, social support, negative social relationships) that might mediate or moderate this relation. Past suicide attempters were found to have higher levels of depressive symptoms, anxious symptoms, and conduct problems at a later time than youths who neither attempted nor ideated. Psychosocial factors failed to mediate this relation. The interaction among past suicidality, social support, and negative relationships was associated with subsequent changes in all 3 psychological distress indicators 6 months later. Specifically, high levels of support (either from family or friends) or negative relationships were found to predict increased psychological distress among those with a history of suicide attempts, but not among youths without a history of suicidality. The findings suggest that GLB youths who attempt suicide continue to have elevated levels of psychological distress long after their attempt and they highlight the importance of social relationships in the youths psychological distress at follow-up.Earlier versions of this paper were presented at the biannual meeting of the European Association for Research on Adolescence, Oxford, UK, September 2002; and, at the annual meeting of the American Public Health Association, San Francisco, CA, November 2003.Associate Professor of Psychology, The City University of New York—The City College and Graduate Center. Received PhD in psychology from New York University. Research interests include the relation of identity to health, the intersection of multiple identities, and the relation of violence to health.Doctoral candidate in Social/Personality Psychology and Health Psychology, The City University of New York—Graduate Center. Research interests include the role of social relationships in the preservation of health and well-being.Research Scientist, HIV Center for Clinical and Behavioral Studies, New York State Psychiatric Institute; and Assistant Professor, Department of Psychiatry, Columbia University. Received doctorate in social welfare (DSW) from The City University of New York—Graduate Center. Research and clinical interests include the design and implementation of interventions for gay, lesbian, and bisexual adolescents. 相似文献
495.
496.
This article analyzes the costs and emissions characteristics of methanol vehicles. The cost-effectiveness of methanol—the cost per ton of reactive hydrocarbon emissions reduced—is calculated and compared to the cost-effectiveness of other hydrocarbon reduction strategies. Methanol is found to cost from $33,000 to nearly $60,000 per ton, while several other options are available for under $10,000 per ton. The cost per part-per-million reduction in peak ambient ozone levels is also computed for two cities, Houston and Philadelphia. Despite the greater improvement in ozone in Philadelphia than Houston, methanol is found to be more cost-effective in Houston. This result occurs because Houston's distribution and marketing costs are lower than Philadelphia's. The costs in both cities, however, are far higher than estimates of the benefits from acute health improvements. Finally, the reduction in ozone exposure in Los Angeles is estimated and the costs of the reduction compared with an estimate of acute health benefits. Again, the benefits fall far short of the costs. 相似文献
497.
Margaret N. Maxey 《Society》1992,29(3):41-49
She is president of the National Institute for Engineering Ethics. 相似文献
498.
499.
Margaret E. Beare 《Crime, Law and Social Change》1997,28(2):155-172
The intention of this paper is to serve in part as a warning to the international community concerned about corruption, to
keep the focus based on the critical analysis of empirically verifiable information. In ways similar to how theorists spoke
about organized crime in the 1960's and 1970's, articles today attempt to refer to corruption as if there were one agreed
upon definition. However, like the concept “organized crime”, the term “corruption” involves diverse processes which have
different meanings within different societies. Corruption (or a focus on corruption), may be the means toward very diverse
ends and each may have a different impact on the society. While in some societies corruption may correctly be seen to be the
“cause” of forms of social disorganization, in other situations corruption may be the “result” of larger changes. Understanding
the processes within a specific context allows one to understand the nature of the corruption. Corruption rhetoric may too
easily become apolitical platform for ranking and evaluating nations as to their worth based on criteria that lose meaning
when applied across jurisdictions.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
500.
This article reports on a study of the case settlement process used in the Connecticut Superior Court Family Division to resolve child protection and placement disputes. Key elements of the formally titled Case Status Conference are presented and evaluated for their effectiveness and efficiency through interviews with legal and judicial professionals familiar with the conferencing procedure. 相似文献