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341.
Abstract

This paper provides an analysis of data on school security measures which were obtained from a survey administered to a sample of 230 high school students. The majority of students indicated that the school police officers and security officers help keep the schools safe and that the drug-sniffing dogs help reduce drugs in the schools, but there was no clear consensus among the students on the issues of whether the video surveillance cameras increase safety, whether the police and security officers should search students with metal detectors, or whether there should be more police and security officers in the schools. The only security measure which the majority of students disliked was the policy that all backpacks be translucent. An examination of gender differences in student perceptions of school security measures shows that males were significantly more likely than females to negatively evaluate the school police officers and to oppose the use of metal detectors in the schools. Finally, the data indicate that the aforementioned security strategies have little impact on the presence of drugs and weapons in the schools. The policy implications are discussed.  相似文献   
342.
《Critical Horizons》2013,14(2):127-155
Abstract

From the late seventeenth century on the idea of culture underwent a gradual transformation. Originally this concept referred essentially to the “refined” way of life of the ruling social elite (which certainly included among others also such activities as listening and making music, reading works of literature, commissioning works of fine art). Popular culture, on the other hand, refers to the usually collective practices of groups of rural and urban workers taking the form of performance. They were not only excluded from refined culture, but it was regarded as completely unsuitable for them, potentially creating dangerous social aspirations. It is with the great social transformation from feudal to bourgeois society that the idea of refined culture was replaced by that of “high culture” encompassing both the arts and the sciences: works claiming universal human significance. This “high culture” for a considerable time coexisted with the remnants of popular culture. It has been only due to the great technical advances that its true opposite, “mass culture” emerged, at the turn to twentieth century, claiming an empirical universality: being understandable and truly interesting to everyone. In economic respect, there is a competitive relation between high and mass culture. However, it is argued that there can be no cultural competition between them. For they posit differing and potentially co-existing receptive attitudes. The characterisation of this difference and the discussion of the seeming exceptions to the so-articulated conceptual scheme occupies the concluding part of this essay.  相似文献   
343.
Abstract: GeneMarker® HID was assessed as a software tool for the analysis of forensic short tandem repeat (STR) data and as a resource for analysis of custom STR multiplexes. The software is easy to learn and use, and includes design features that have the potential to reduce user fatigue. To illustrate reliability and accuracy, STR data from both single‐source and mixture profiles were analyzed and compared to profiles interpreted with another software package. A total of 1898 STR profiles representing 28,470 loci and more than 42,000 alleles were analyzed with 100% concordance. GeneMarker HID was also used to successfully analyze data generated from a custom STR multiplex, with simplified and rapid implementation. Finally, the impact of the user‐friendly design features of the software was assessed through a time scale study. The results suggest that laboratories can reduce the time required for data analysis by at least 25% when using GeneMarker HID.  相似文献   
344.
In this paper, we use bloodstains to illustrate an approach for identifying latent evidence on dark cloth using near infrared (NIR) photography combined with high dynamic range (HDR) photography techniques. NIR photography alone has been used to capture latent evidence that cannot be seen in normal ambient light. HDR techniques combine multiple bracketed photographs of the same image to increase the dynamic range of the photograph which can provide greater contrast. Using NIR photography alone, we were able to detect a bloodstain up to a 1/16 dilution, an improvement over previous studies. Combining NIR photography with the HDR process resulted in a noticeable increase in visibility up to 1/16 dilution when compared to NIR photographs alone. At 1/32 dilution, we were able to detect bloodstains that were not visible using NIR alone. NIR is a useful tool for imaging latent evidence, and combining NIR with HDR consistently provides better results over NIR alone.  相似文献   
345.
Lubricating oil comparisons impact a variety of forensic investigations, including cases where oil was transferred from a suspect vehicle to the crime scene or victim. In this study, high-temperature gas chromatography/mass spectrometry was used to examine the influence of oil mixtures and oil changes over time on the comparison of known and questioned lubricating oils. Varying concentrations of oil mixtures were prepared and showed the potential for identifying individual components. Motor oils from 18 automobiles monitored over a 2-month period did not demonstrate significant changes in the chromatographic data. Chemometric analysis of motor oil mass spectral data provided little information regarding differentiation of, or changes in, the samples. Power steering fluid (PSF) from a naturally occurring leak collected from several locations was consistent with the PSF in the automobile's reservoir, and the PSF composition did not change over time.  相似文献   
346.
选用断乳仔猪45头,随机分为3组,每组5个重复,每个重复3头,采用完全随机化设计进行生长试验,研究了不同添加水平(5、125、250mg/kg)的硫酸铜日粮对猪下丘脑及中脑儿茶酚胺类物质分泌的影响。结果,日粮中添加125mg/kg(P<0.01)、250mg/kg(P<0.05)硫酸铜均显著提高了中脑、下丘脑多巴胺含量,但是随着铜水平的提高,多巴胺含量呈下降趋势;中脑黑质去甲肾上腺素浓度在试验组与对照组之间有显著差异,并且随着铜浓度的提高有升高趋势。据此推断,高剂量铜可能通过调节中枢儿茶酚胺代谢,促进生长激素的分泌进而促进动物生长。  相似文献   
347.
A case of fatal intoxication from metformin   总被引:1,自引:0,他引:1  
A case of fatal intoxication from metformin is presented. The decedent was an obese 58-year-old-woman with type II diabetes, in whom severe lactic acidosis secondary to metformin accumulation was precipitated by acute renal failure. She had been on metformin 500 mg twice a day. Postmortem blood was deproteinated with acetonitrile, washed with dichloromethane, and the resulting supernatant injected into high-performance liquid chromatography system. Separation was performed on a analytical 125 x 4 mm i.d. RP-8 column. The wavelength was set at 235 nm. The mobile phase was acetonitrile (40%), sodium lauryl sulfate, and sodium dihydrogen phosphate adjusted to pH 5.1 (60%) at a flow rate of 1.0 mL/min. The concentration of metformin in postmortem blood was 77.3 microg/mL. The qualitative result was also confirmed by LC/APCI/MS/MS analysis.  相似文献   
348.
高校高学历辅导员职业倦怠问题已引起广泛关注。构建高学历辅导员与高校之间良好的心理契约,能增强其对高校组织的认同感,有效减少职业倦怠的产生。该心理契约的内容主要包括对所在高校的认同程度、对辅导员职业的理解、对自身的要求和辅导员的工作对象。通过对学生、学校和辅导员自身等三个层面的背景分析,从职业生涯、参与管理、职业承诺、高校组织文化、职业心理辅导等五个方面入手采取有效措施,以缓解高学历辅导员职业倦怠现象。  相似文献   
349.
A rapid and simple gas chromatography-mass spectrometry (GC-MS) method was developed and validated for the simultaneous detection and quantification of five psychotropic phenylalkylamines (amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine, and norketamine) in toenails. After external decontamination, nail clippings were mechanically pulverized with a bead mill and then incubated in methanol under ultrasonication at 50°C for 1 h. The resulting solutions were evaporated to dryness, derivatized, and analyzed by GC-MS. The intra- and inter-day precisions were within 10.7% and 13.9%, respectively. The intra- and inter-day accuracies were -4.2% to 5.0% and -2.4% to 8.4%, respectively. Limits of detection and quantification for each analyte were lower than 0.024 and 0.08 ng/mg, respectively. The recoveries were in the range of 80.6-87.5%. The results indicated that the proposed method is a simple, rapid, accurate, and precise for quantification of five phenylalkylamines in nails. The method was successfully applied to the simultaneous detection and quantification of phenylalkylamines in nail samples of possible drug abusers.  相似文献   
350.
《Justice Quarterly》2012,29(4):462-480
Little research has assessed the effects of juvenile justice involvement during high school on educational outcomes. Using the National Longitudinal Survey of Youth 1997, this study assesses the effect of first‐time arrest and court involvement during high school on educational attainment. In addition, differential effects by structural location are examined. Findings suggest support for the labeling perspective. First‐time court appearance during high school increases the chances of dropping out of high school independent of involvement in delinquency. Furthermore, the effect of court appearance is particularly detrimental to less delinquent youths.  相似文献   
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