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841.
Public subsidies to industries firms incentives to alter their behavior. When calculating the effects of such programs, previous assessments of transit subsidies have not included the effects of these incentives on the firms' output. This article reports the responses of mass transit firms to the federal transit subsidy program and changes the Transportation Equity Act for the 21st Century (TEA 21) made to that program, as predicted by a structural model of output choice. TEA 21 increases bus service in medium‐sized cities by 6‐8 percent, butincreases service in large cities by only 1‐2 percent. The formula's incentive tier is weak, and the size of the subsidy depends little on whether that output results in increased ridership. The formula could be redesigned to provide stronger incentives to lower cost and increase ridership, thus encouraging a more efficient response from transit firms. © 2001 by the Association for Public Policy Analysis and Management.  相似文献   
842.
The purpose of this study was to explore individual- and school-level policy characteristics on student smoking behavior using an ecological perspective. Participants were 24,213 (51% female) Grade 10–11 students from 81 schools in five Canadian provinces. Data were collected using student self-report surveys, written policies collected from schools, interviews with school administrators, and school property observations to assess multiple dimensions of the school tobacco policy. The multi-level modeling results revealed that the school a student attended was associated with his/her smoking behavior. Individual-level variables that were associated with student smoking included lower school connectedness, a greater number of family and friends who smoked, higher perceptions of student smoking prevalence, lower perceptions of student smoking frequency, and stronger perceptions of the school tobacco context. School-level variables associated with student smoking included weaker policy intention indicating prohibition and assistance to overcome tobacco addiction, weaker policy implementation involving strategies for enforcement, and a higher number of students smoking on school property. These findings suggest that the school environment is important to tobacco control strategies, and that various policy dimensions have unique relationships to student smoking. School tobacco policies should be part of a comprehensive approach to adolescent tobacco use.  相似文献   
843.
Abstract:  The examination of skull sexual dimorphism has been the subject of numerous morphologic and craniometric studies, but the disadvantage of these studies is that they are dependent on the experience of the operator and involve subjectivity. In 1996, a team from Taiwan refined the methods enabling the sex of an individual to be determined using cephalometric plots made from lateral teleradiography. To validate their work using a European population, 114 dry skulls (59 men and 55 women) were examined. Cephalometric plots were made on lateral teleradiography with an orthodontic software and 18 cephalometric variables were analyzed. Sex was determined with 95.6% accuracy using the 18 variables discriminant function. A subset of eight variables was selected and could predict sex with the same accuracy. In conclusion, it can be said that skull-sexing methods using lateral teleradiography seem always suitable but the most indicative variables could differ relative to the ethnic population concerned.  相似文献   
844.
845.
Abstract:  Screening methods capable of identifying DNA samples that will not yield short tandem repeat (STR) profiles are desired. In the past, quantitation methods have not been sensitive enough for this purpose. In this study, low level DNA samples were used to assess whether Quantifiler™ has a minimum quantitation value below which STR profiles would consistently fail to be detected. Buccal swabs were obtained and the DNA extracted, quantified, and serially diluted to concentrations ranging from 0.002 to 0.250 ng/μL. Samples were analyzed once with Quantifiler™, followed by Profiler Plus™ amplification and capillary electrophoresis analysis. An absolute minimum value below which STR results were unobtainable could not be defined. From the 96 low level samples tested, STR loci (including one full profile) were successfully amplified and detected from 27% of the samples "undetected" by Quantifiler™. However, no STR alleles were detected in 73% of these "undetected" samples, indicating that Quantifiler™ data may be useful for predicting STR typing success.  相似文献   
846.
Despite the lack of consensus regarding the meaning or significance of race or ethnicity amongst scientists and the lay public, there are legal requirements and guidelines that dictate the collection of racial and ethnic data across a range of institutions. Legal regulations are typically created through a political process and then face varying kinds of resistance when the state tries to implement them. We explore the nature of this opposition by comparing responses from businesses, scientists, and science-oriented businesses (pharmaceutical and biotechnology companies) to U.S. state regulations that used politically derived racial categorizations, originally created to pursue civil rights goals. We argue that insights from cultural sociology regarding institutional and cultural boundaries can aid understanding of the nature of resistance to regulation. The Food and Drug Administration's guidelines for research by pharmaceutical companies imposed race categories on science-based businesses, leading to objections that emphasized the autonomy and validity of science. In contrast, similar race categories regulating first business by the Equal Employment Opportunity Commission (EEOC) and later scientific research sponsored by the National Institutes of Health (NIH) encountered little challenge. We argue that pharmaceutical companies had the motive (profit) that NIH-supported scientists lacked and a legitimate discourse (boundary work of science) that businesses regulated by the EEOC did not have. The study suggests the utility of a comparative cultural sociology of the politics of legal regulation, particularly when understanding race-related regulation and the importance of examining legal regulations for exploring how the meaning of race or ethnicity are contested and constructed in law.  相似文献   
847.
This study examined the effect of race on the pretrial release decision for drug offenders. Although this decision point has not been examined as extensively as the final sentencing decision, it is a critical discretion point which impacts defendants’ future sentencing outcomes. The results found that race had a significant impact on judges’ decisions to release a defendant on recognizance, with black defendants less likely to receive this release status. Race was not significant, however, in the decision of bail amount or in the likelihood to post bail. These results are consistent with the focal concerns perspective which suggests that black defendants are viewed by courts as more dangerous and blameworthy and thereby, less likely to be released on their own recognizance.  相似文献   
848.
The current paper aimed to investigate the effectiveness of five law enforcement interventions in disrupting and dismantling criminal networks. We tested three law enforcement interventions that targeted social capital in criminal networks (betweenness, degree and cut-set) and two interventions that targeted human capital (actors who possess money and those who possess precursor chemicals). These five interventions are compared with each other and with random (opportunistic) removal of actors in two settings: (i) with network adaptation incorporated into the simulations and (ii) without network adaptation. Results illustrate that the removal of actors based on betweenness centrality was the most efficient strategy, leading to network disruption in the least number of steps and was relatively consistent across replications. Targeting actors who possessed money was the second most effective overall and was also relatively consistent in its disruptive effect.  相似文献   
849.
Sampling site, technique, and time influence postmortem drug concentrations. In 57 cases, we studied drug concentration differences as follows: subclavian vein‐dissection/clamping versus blind stick, femoral vein‐dissection/clamping versus blind stick, right cardiac chamber, and popliteal vein‐dissection and clamping only. Cases were distributed in group #1 (all cases with both techniques), group #2 (dissection/clamping), and group #3 (blind stick). Sampled drugs were diazepam, methadone, morphine, and their metabolites. To assess PMR, mean concentrations and ratios were calculated for each group. Time‐dependent variations of blood concentrations and ratios were also assessed. Results indicate that site, method, and time may influence postmortem distribution interpretation in different ways. Popliteal blood seems less subject to PMR. In conclusion, our study is the first to evaluate concurrently three main aspects of PMR and confirms that the popliteal vein may represent a site that is more resistant to the changes seen as a result of PMR.  相似文献   
850.
Many urban, low-income adolescents experience violence, often resulting in posttraumatic stress disorder (PTSD) and depression. Narrative Exposure Therapy (NET) facilitates therapeutic processing of traumatic memories. This purpose of this study is to examine the feasibility of NET among adolescents at-risk for PTSD and depression. Two community-based agencies hosted five focus groups with adolescents (n = 28), aged 18–21, predominantly African- American (71 %) and female (61 %) and one with adolescent service providers (n = 11). Pope’s coding framework (2000) and the Socio-Ecological Model for violence prevention (Krug et al. in The Lancet, 360(9339), 1083–1088, 2002) elicited perceived barriers and facilitators to NET. Individual, relationship, and community level barriers and facilitators to NET therapy engagement were identified. The findings indicate participants have favorable attitudes about NET and the provision of the therapy within trusted community agencies. The results will inform the next steps of NET implementation, training, and psychoeducation.  相似文献   
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