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271.
Y Katsuragawa 《Forensic science international》1999,101(1):43-48
BACKGROUND: Methamphetamine, a derivative of amphetamine, has been said to cause mainly mental dependency in humans, but only little is known about its physical dependency. Like other narcotics, it may have chronic effects on the human body, so, this study was planned to evaluate it by examining the bone quality of the skeletal system. METHOD: Among the convicts serving in Fuchu Prison, two groups of people were chosen according to their methamphetamine experience. The bone quality of the calcaneus of both abusers (n = 59, ages 41 +/- 11 years) and controls (n = 50, aged 45 +/- 13 years) was examined with an Achilles ultrasound bone densitometer. SOS (speed of sound) and BUA (broadband ultrasound attenuation), both of which were obtained from the measurement and are an indicator of the strength of bone, were compared between the two groups. RESULTS: The SOS of the abuser group was 1559 +/- 24 (mean +/- SD) m/s and this was significantly lower than that of the control group, 1570 +/- 27 (mean +/- SD) m/s (p = 0.017). The BUAs of the abuser group and the control group were 108 +/- 10 and 110 +/- 10 (mean +/- SD) dB/MHz, respectively, and there was no significant difference between them (p = 0.181). CONCLUSION: There was loss of SOS of the calcaneus in methamphetamine abusers. 相似文献
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274.
This paper examines the role of the federal government in shaping the relationship between academics scientists and industry.
There exists a potential conflict between government policies encouraging collaboration within academia and the policies encouraging
collaboration between academia and industry. To test and model these potential conflicts, this paper uses data collected in
a 2004–2005 survey by the Research Valuing Mapping Project (a project based at Georgia Tech and led by Barry Bozeman) of more
than 2000 academically based research scientists and engineers. The major finding in this paper shows that academic scientists
working with industry collaborate more (with all types of collaborators) than those that do not collaborate with industry.
However, when examining only those scientist that collaborate with industry, the results reveal a negative relationship between
the amount of time spent collaborating with industry and the number of collaborators; implying that increasing collaboration
with industry leads to less academic–academic collaboration. 相似文献
275.
We examine the flow of federal grants‐in‐aid from the U.S. Environmental Protection Agency (EPA) to the states. We simultaneously model two dependent variables (the flow of EPA funds, and state environmental and natural resource budgets) to identify the independent roles of state political institutions, political preferences, economic and demographic characteristics, and the task environment. Our central focus, though, is on the relationship between grants and state spending after taking into account those direct effects. We examine the evidence for positive association (a flypaper effect) and negative association (crowding out). We show the different roles for political institutions, political preferences, demographic and economic characteristics, and the task environment in each spending context. Most importantly, we find evidence for a flypaper effect between federal funds and state spending: Federal spending and state spending are positively correlated after accounting for the contribution of the unique factors. © 2010 by the Association for Public Policy Analysis and Management. 相似文献
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277.
As students transition into middle school they must successfully negotiate a new, larger peer context to attain or maintain
high social standing. The goal of this study was to examine the extent to which the maintenance, attainment, and loss of a
cool status over the course of the sixth grade is associated with student and classroom levels of physical, verbal, and relational
aggression. To address this goal, we studied a sample of 1985 (55% girls) ethnically diverse adolescents from 99 sixth grade
classrooms in the United States. Attaining a cool status at any point across the school year was associated with stronger
aggressive reputations. Additionally, classroom norms for aggressive behavior moderated the association between changes in
aggression over the school year and the stability of coolness such that students who maintained their coolness across the
school year showed greater increases in their verbally aggressive reputations from fall to spring when they were in classrooms
with higher levels of aggression. The findings illustrate the importance of fitting in with social norms for maintaining a
high social status among a new set of peers in middle school. 相似文献
278.
This study develops and tests a model of economic deprivation and crime using data from 52 nations for the years 1995–1999.
The model, centering on the role of absolute and relative economic deprivation in mediating crime, predicts that social change
causes variation in economic deprivation, which, in turn, leads to variation in crime rates. The results show that the relative
deprivation variable, income inequality, mediates a large portion of the effects of two social change variables, population
growth and urbanization, on homicide, while one of the absolute deprivation variables, GDP, transmits a great part of the
effects of social change variables on theft. Both social change variables were found to have a weak direct connection to homicide
and theft rates. Implications for policy and future research are discussed. 相似文献
279.
Kim SY Shapiro-Mendoza CK Chu SY Camperlengo LT Anderson RN 《Journal of forensic sciences》2012,57(2):364-369
We compared written text on infant death certificates for deaths coded as sudden infant death syndrome (R95), unknown cause (R99), and accidental suffocation (W75). Using US mortality files supplemented with the death certifiers' written text for all infant deaths with International Classification of Diseases (ICD)-10 assigned codes R95, R99, and W75, we formed cause-of-death subcategories from common themes identified from the written text. Among all infant deaths in 2003-2004, the underlying cause of death was listed as R99 for 2128 deaths, R95 for 4408 deaths, and W75 for 931 deaths. Among the postneonatal deaths, the differences in subcategories varied between assigned ICD-10 codes: for R99-coded deaths, 45.8% were categorized as "Unknown" and 48.6% as "Pending"; for R95-coded deaths, 67.7% were categorized as "sudden infant death syndrome (SIDS)"; and for W75-coded deaths, 76.4% were categorized as "Suffocation." Examination of the written text on the death certificates demonstrates variability in the assigned ICD-10 codes which could have an important effect on the estimates of SIDS cases in the United States. 相似文献
280.
This paper discusses the organization of the first international proficiency test (PT) programme on ketamine (K) and norketamine (NK) in hair samples. The primary objective of the programme was to evaluate the analytical capability of participating laboratories on hair analysis for K and NK via comparison of results. Authentic samples, instead of spiked samples were used in the programme to mimic the analysis of incorporated illicit drugs in real-life situations. Eight of the ten participating medical or forensic laboratories from Australia, France, Hong Kong, Italy, Singapore and the USA returned results to the organizer. Quantification methods from these laboratories were confined to GC-MS and LC-MS/MS. Performance assessment based on z-score indicated that only three laboratories achieved satisfactory results for both the analysis of K and NK. It was concluded that the overall performance of the participating laboratories was fair and there is still room for further improvement. Additional similarly designed PT programmes are recommended to be organized in order to encourage reliable measurements of illicit drugs in hair samples. Taking into account the substantial effect on the consensus values within limited number of data points, a recommendation on the provision of reference values assigned by accurate methods will be of benefit to small size PT programmes in the forensic field. 相似文献