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Considerable research has documented associations between adverse life events and internalizing symptoms in adolescents, but much of this research has focused on the number of events experienced, with less attention to the ecological context or timing of events. This study examined life events in three ecological domains relevant to adolescents (i.e., family, peers, themselves) as predictors of the course of depressive symptoms among a community epidemiologically defined sample of 419 (47.2% females) urban African American adolescents. Given that youth depressive symptoms change over time, grade level was examined as a moderator. For males, the strength of associations between life events happening to participants, family life events, and peer life events and depressive symptoms did not change from grades 6–9. For females, the strength of the association between peer life events and depressive symptoms did not change over time, but the strength of associations between life events happening to participants and family life events and females’ depressive symptoms decreased over time. Implications of the findings and directions for future research are discussed.  相似文献   
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Recently, there has been much debate about what kinds of genetic markers should be implemented as new core loci that constitute national DNA databases. The choices lie between conventional STRs, ranging in size from 100 to 450 bp; mini-STRs, with amplicon sizes less than 200 bp; and single nucleotide polymorphisms (SNPs). There is general agreement by the European DNA Profiling Group (EDNAP) and the European Network of Forensic Science Institutes (ENFSI) that the reason to implement new markers is to increase the chance of amplifying highly degraded DNA rather than to increase the discriminating power of the current techniques. A collaborative study between nine European and US laboratories was organised under the auspices of EDNAP. Each laboratory was supplied with a SNP multiplex kit (Foren-SNPs) provided by the Forensic Science Service, two mini-STR kits provided by the National Institute of Standards and Technology (NIST) and a set of degraded DNA stains (blood and saliva). Laboratories tested all three multiplex kits, along with their own existing DNA profiling technique, on the same sets of degraded samples. Results were collated and analysed and, in general, mini-STR systems were shown to be the most effective. Accordingly, the EDNAP and ENFSI working groups have recommended that existing STR loci are reengineered to provide smaller amplicons, and the adoption of three new European core loci has been agreed.  相似文献   
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We have developed a robust single nucleotide polymorphism (SNPs) typing assay with co-amplification of 25 DNA-fragments and the detection of 35 human Y chromosome SNPs. The sizes of the PCR products ranged from 79 to 186 base pairs. PCR primers were designed to have a theoretical Tm of 60 +/- 5 degrees C at a salt concentration of 180 mM. The sizes of the primers ranged from 19 to 34 nucleotides. The concentration of amplification primers was adjusted to obtain balanced amounts of PCR products in 8mM MgCl2. For routine purposes, 1 ng of genomic DNA was amplified and the lower limit was approximately 100 pg DNA. The minisequencing reactions were performed simultaneously for all 35 SNPs with fluorescently labelled dideoxynucleotides. The size of the minisequencing primers ranged from 19 to 106 nucleotides. The minisequencing reactions were analysed by capillary electrophoresis and multicolour fluorescence detection. Female DNA did not influence the results of Y chromosome SNP typing when added in concentrations more than 300 times the concentrations of male DNA. The frequencies of the 35 SNPs were determined in 194 male Danes. The gene diversity of the SNPs ranged from 0.01 to 0.5.  相似文献   
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Two experiments investigated how mock jurors react to testimony involving claims of a repressed memory in a case involving child sexual assault. Participants read a fictional civil trial summary presented in one of three conditions: (a) immediate condition—the alleged victim testified immediately after the incident; (b) repressed condition—the alleged victim reported the assault 1–39 years later, after remembering it for the first time; or (c) not-repressed condition—the alleged victim reported the assault 1–39 years later, but the memory of the assault had been present for those years. When there was any type of delayed reporting, either the age of the alleged victim at the time of the assault was constant and her age at reporting varied (Experiment 1) or the age of the alleged victim at the time of the assault varied and her age at reporting remained constant (Experiment 2). The results showed that (1) a delay in reporting an incident adversely affected believability of the alleged victim and led to fewer rulings in support of the plaintiff compared to reporting it immediately, (2) longer delays in reporting generally led to lower alleged victim believability and fewer decisions in support of the plaintiff than shorter delays, (3) the age of the alleged victim at the time of the incident was a critical variable in determining belief of the alleged victim, and (4) men generally rated believability of the alleged victim lower and ruled in favor of the plaintiff less often than women. The results are discussed in terms of the psychosocial factors affecting the perception of delayed reporting in a child sexual assault trial.  相似文献   
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Urban development, and particularly the improvement of basic services delivery, is still approached in mostly technical terms by international development actors and municipalities of the Global South. Sanitation planning, for instance, remains the realm of engineers despite decades of evidence that conventional approaches focusing on infrastructure upgrading have failed to tackle socio-environmental challenges. Against this background, this paper explores sanitation planning in Mandalay, the second largest city of Myanmar. Here, the Asian Development Bank and a French consulting firm have seized the opportunity created by the country’s recent opening to embark with the municipality on a multi-million dollar scheme: the Mandalay Urban Services Improvement Project (MUSIP). Drawing upon insights from critical development studies, the paper argues that the MUSIP can be interpreted as an ‘anti-politics machine’ that ignored local needs and proposed disputable solutions to local sanitation challenges. The paper further explores how this machine jeopardised urban development in Mandalay more generally, and was eventually challenged by the municipality. The paper concludes that the case is not unique and illustrates how urban development is today being reshaped throughout Myanmar, while it also shows the continued relevance of the ‘anti-politics’ framework to understand contemporary urban development assistance projects.  相似文献   
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Detection of trace quantities of explosive residues plays a key role in military, civilian, and counter-terrorism applications. To advance explosives sensor technology, current methods will need to become cheaper and portable while maintaining sensitivity and selectivity. The detection of common explosives including trinitrotoluene (TNT), cyclotrimethylenetrinitramine, cyclotetramethylene-tetranitramine, pentaerythritol tetranitrate, 2,4,6-trinitrophenyl-N-methylnitramine, and trinitroglycerin may be carried out using a three-step process combining "turn-off" and "turn-on" fluorimetric sensing. This process first detects nitroaromatic explosives by their quenching of green luminescence of polymetalloles (lambda em approximately 400-510 nm). The second step places down a thin film of 2,3-diaminonaphthalene (DAN) while "erasing" the polymetallole luminescence. The final step completes the reaction of the nitramines and/or nitrate esters with DAN resulting in the formation of a blue luminescent traizole complex (lambda(em) = 450 nm) providing a "turn-on" response for nitramine and nitrate ester-based explosives. Detection limits as low as 2 ng are observed. Solid-state detection of production line explosives demonstrates the applicability of this method to real world situations. This method offers a sensitive and selective detection process for a diverse group of the most common high explosives used in military and terrorist applications today.  相似文献   
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Prediction of human eye colour by forensic genetic methods is of great value in certain crime investigations. Strong associations between blue/brown eye colour and the SNP loci rs1129038 and rs12913832 in the HERC2 gene were recently described. Weaker associations between eye colour and other genetic markers also exist. In 395 randomly selected Danes, we investigated the predictive values of various combinations of SNP alleles in the HERC2, OCA2 and MATP (SLC45A2) genes and compared the results to the eye colours as they were described by the individuals themselves. The highest predictive value of typing either the HERC2 SNPs rs1129038 and/or rs12913832 that are in strong linkage disequilibrium was observed when eye colour was divided into two groups, (1) blue, grey and green (light) and (2) brown and hazel (dark). Sequence variations in rs11636232 and rs7170852 in HERC2, rs1800407 in OCA2 and rs16891982 in MATP showed additional association with eye colours in addition to the effect of HERC2 rs1129038. Diplotype analysis of three sequence variations in HERC2 and one sequence variation in OCA2 showed the best discrimination between light and dark eye colours with a likelihood ratio of 29.3.  相似文献   
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