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91.
Prevention science has produced information about risk and protective factors that predict adolescent drug use and related problem behaviors. This paper investigates the Communities That Care Youth Survey that measures multiple risk and protective factors. Using a sample of 172,628 students who participated in surveys administered in seven states in 1998, analyses were conducted to test the factor structure of these risk and protective factors and to test the equivalence of the factor models across five racial/ethnic groups (African Americans, Asians or Pacific Islanders, Caucasians, Hispanic Americans, and Native Americans), four grade levels (6th, 8th, 10th, and 12th) and both gender groups. Results support the construct validity of the surveys risk and protective factor scales and indicate that the measures are equally reliable across males and females and five racial/ethnic groups. Implications of these findings for science-based prevention planning are discussed.  相似文献   
92.
Degradation of human DNA extracted from forensic stains is, in most cases, the result of a natural process due to the exposure of the stain samples to the environment. Experiences with degraded DNA from casework samples show that every sample may exhibit different properties in this respect, and that it is difficult to systematically assess the performance of routinely used typing systems for the analysis of degraded DNA samples. Using a batch of artificially degraded DNA with an average fragment size of approx. 200 bp a collaborative exercise was carried out among 38 forensic laboratories from 17 European countries. The results were assessed according to correct allele detection, peak height and balance as well as the occurrence of artefacts. A number of common problems were identified based on these results such as strong peak imbalance in heterozygous genotypes for the larger short tandem repeat (STR) fragments after increased PCR cycle numbers, artefact signals and allelic drop-out. Based on the observations, strategies are discussed to overcome these problems. The strategies include careful balancing of the amount of template DNA and the PCR cycle numbers, the reaction volume and the amount of Taq polymerase. Furthermore, a careful evaluation of the results of the fragment analysis and of automated allele calling is necessary to identify the correct alleles and avoid artefacts.  相似文献   
93.
This study investigated to what extent abuse-related symptoms and family functioning are related to intra- or extrafamilial sexual abuse. One hundred adolescents (12 to 18 years old) were recruited shortly after disclosure of the abuse. Information from the participants was obtained through self-report questionnaires and a semistructured interview. Fifty-three percent of the adolescents reported clinically significant symptoms. Data did not support the idea that intrafamilial sexually abused adolescents report more symptoms than extrafamilial sexually abused adolescents. Type of abuse did not account for the differences and variety of reported symptoms or for differences in family functioning. Family functioning-in particular, lack of cohesion- was an independent contributor to internalizing trauma-related problems.  相似文献   
94.
The amphetamine derivative 3,4-methylenedioxymethamphetamine (MDMA, "Ecstasy" is a currently used or abused designer drug and fatalities are frequently encountered in forensic practice. However, the question remains open whether an MDMA blood level can be toxic or even potentially lethal. In order to provide insight in the interpretation of a detected MDMA concentration, the distribution of MDMA and its metabolite 3,4-methylenedioxyamphetamine (MDA) in various body fluids and tissues was studied and discussed in two different fatalities. Apart from peripheral blood samples (such as femoral and subclavian blood), various blood samples obtained centrally in the human body and several body fluids (such as vitreous humour) were examined. In addition, various tissues such as cardiac muscle, lungs, liver, kidneys, and brain lobes were analysed. In contrast to the peripheral blood levels, high MDMA and MDA levels were found in cardiac blood and the majority of the organs, except for the abdominal adipose tissue. The high concentrations observed in all lung lobes, the liver and stomach contents indicate that post-mortem redistribution of MDMA and MDA into cardiac blood can occur and, as a result, blood sampled centrally in the body should be avoided. Therefore, our data confirm that peripheral blood sampling remains "the golden standard". In addition, a distinct difference in peripheral blood MDMA concentrations in our two overdose cases was established (namely 0.271 and 13.508 microg/ml, respectively). Furthermore, our results suggest that, if a peripheral blood sample is not available and when putrefaction is not too pronounced, vitreous humour and iliopsoas muscle can be valuable specimens for toxicological analysis. Finally, referring to the various mechanisms of death following amphetamine intake, which can result in different survival times (e.g. cardiopulmonary complications versus hyperthermia), the anatomo-pathological findings and the toxicological results should be considered as a whole in arriving at a conclusion.  相似文献   
95.
This contribution aims at examining the extent to which patent related indicators are relevant for shedding light on the notion of excellence within knowledge-generating institutions. Traditionally, excellence has been looked upon as the ability to create interesting and valuable new scientific concepts, theories and data. From such a perspective, scientific excellence can be assessed through scientometric measures of publication output and impact. The recent interest in the entrepreneurial phenomenon within knowledge-generating institutes justifies efforts to examine the relevancy of broadening the set of indicators used to assess such institutions into the direction of entrepreneurial excellence. In this paper we will examine the relevancy of using patent data in order to delineate such additional, more entrepreneurial oriented, indicators. The arguments and findings presented in this respect will lead us to a plea for the use of these indicators in a contextualized manner.  相似文献   
96.
97.
The Illusion of Transparency in Negotiations   总被引:1,自引:0,他引:1  
The authors examined whether negotiators are prone to an illusion of transparency, or the belief that their private thoughts and feelings are more discernible to their negotiation partners than they actually are. In Study One, negotiators who were trying to conceal their preferences thought that their preferences had leaked out more than they actually did. In Study Two, experienced negotiators who were trying to convey information about some of their preferences overestimated their partners' ability to discern them. The results of Study Three rule out the possibility that the findings are simply the result of the curse of knowledge, or the projection of one's own knowledge onto others. Discussion explores how the illusion of transparency might impede negotiators' success.  相似文献   
98.
This study was conducted in an attempt to develop a metallographic method for the investigation of pipe bombings. Three common pipe materials, ASTM A53 steel, AISI 304L stainless steel, and 6061-T6 aluminum, were shock-loaded using five high explosives and three propellants. The explosives used were ANFO, Composition C4, C6 detasheet, nitroglycerine-based dynamite, and flake TNT. The propellants used were FFFFg black powder. Red Dot smokeless powder, and Turbo Fuel A. The post-blast microstructure, hardness, and, in the case of 304L, transformed martensite content were examined for each test. The damage done to the microstructure was found to increase with increasing detonation velocity of the explosives and increase in pressure generated by the shock-metal interaction. Material hardness and, in the case of 304L, martensite content showed a sharp increase followed by a plateau as the shock pressure and detonation velocity increased.  相似文献   
99.
100.
This study examined the impact of types of women's verbal refusals, and the timing of her refusal, on men's discrimination of when a female wants her partner to stop making sexual advances. Male students were randomly assigned to 1 of 6 conditions (Explanations × Intimacy Levels). Before listening to an audiotape of a date rape, participants were told they would be listening to an interaction between a man and a woman who had just returned from a date. They were instructed to indicate when the woman wanted the man to stop making sexual advances by pressing a switch that synchronously stopped a timer (yielding the measure of latency). In the vignette, the woman provided an explanation for not engaging in sexual intercourse on the date either during kissing or when the man attempted to touch her breasts. She offered one of three reasons for refusing his sexual advances; fear of pregnancy, waiting until marriage, too early in the relationship. Results revealed an interaction in which participants in the too early in the relationship explanation at the level of breast contact condition displayed significantly longer latencies than individuals in the other groups. The implications of the findings are discussed.  相似文献   
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