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101.
A number of recent studies have explored the consequences ofinterracial peer effects on the academic and social performanceof minority students. This article contributes to that discussion,focusing, however, on perceptions rather than behaviors. Theanalysis suggests that exposure to white peers is associatedwith declining perceptions of racial justice among black andLatino high school students. While cautioning against causalinterpretations of this finding, the article suggests that theintegrationist aims of Brown v. Board of Education will notbe satisfied without more thoughtful and vigorous desegregationefforts.  相似文献   
102.
103.
Recently criminologists have begun to explore the importance of disaggregating frequency measures of self-reported delinquency into the separate decisions of initiation and continuation. Given that labeling makes predictions concerning continuation, the purpose of this paper is twofold. The first is to test the ability of an informal labeling model to predict the decision to continue delinquent behavior once it is initiated. The second purpose is to address the broader question of whether disaggregation matters. The findings support the idea that the informal labeling model is predictive of the decision to continue delinquent behavior. The findings also suggest that, at least for a measure of general delinquency, there are some differences to be found by choosing the appropriate sample and form of the dependent variable.  相似文献   
104.
105.
Deoxyribonucleic acid (DNA) typing of ribosomal ribonucleic acid (rRNA) genes was performed with a polymerase chain reaction (PCR) assay for species identification. A variable region of the 28S ribosomal RNA gene was amplified with primers complementary to flanking sequences phylogenetically well conserved. The products of twelve animal DNAs (human, Japanese monkey, dog, cattle, pig, cat, rabbit, mouse, rat, chicken, frog, and fish) were separated by polyacrylamide gel electrophoresis, each revealing a few bands ranging from 150 to 100 base pairs. The band patterns obtained from each DNA sample differed in number and size, which indicates the applicability of the method to species identification. Samples containing either as little as 1 pg of DNA or degraded DNA of 0.2 to 0.5 kb in length were able to give detectable bands. Postmortem human tissue DNAs were tested as an example. They showed a pattern identical to the human control one, which was distinct from those of the other animals examined.  相似文献   
106.
Social scientists have theorized about the cycle of domestic violence in family abuse. Little research has addressed dating violence as a consequence to the experience of domestic violence by children. This article deals with the self-reported experience of dating violence by high school students from abusive and nonabusive households. A survey was conducted of 1,353 students in a rural area of North Dakota. Results indicated that students from abusive households showed significantly higher incidence of dating violence than those from homes where no abuse was evident. However, less than one in five of the students from abusive home reported dating violence, providing little support for the cycle of violence hypothesis. Students from abusive homes viewed violence as negatively as students from nonabusive homes. Thus, while there are significant differences between the two groups, there are also important similarities. Although there is apparently a greater risk of dating violence among students who have experienced violence at home, these data do not support the idea of an inescapable pattern of violence among adolescents who have experienced violence themselves.  相似文献   
107.
This article investigates the effect of Computer Assisted Monitoring of Offenders (CAMO) on probation outcome. In a comparison sample, the effect of CAMO treatment is compared to the effect of “regular” probation. In addition to testing the effects of CAMO as an intermediate treatment, methodological issues, such as level of probation restrictiveness and the effects of prior criminal involvement on probation outcome, are tested. Although the results are mixed, they indicate that level of probation restrictiveness and prior criminal involvement have a greater effect on probation outcome than does CAMO. These findings have ramifications for researchers comparing CAMO probationers to “regular” probationers and for those comparing different CAMO programs. An earlier version of this paper was presented at the Western Social Science Association’s 1992 annual conference.  相似文献   
108.
The authors examine the characteristics of threatening and otherwise inappropriate communications sent to members of the U.S. Congress by a sample of 86 subjects, 20 of whom threatened assassination. We quote excerpts from these letters and provide quantitative data on such variables as the volume, duration, form, and appearance of such communications; the enclosures; the subjects' perceived relationships to the recipients; the thematic content of the communications; and the messages and threats communicated. Comparisons between 43 subjects who pursued encounters with members of Congress and 43 who did not revealed 17 factors associated with such pursuit. In this population, threateners were significantly less likely to pursue an encounter than inappropriate letter writers who did not threaten, regardless of the type of threat or the harm threatened. Inappropriate letters to members of Congress are compared with those directed to Hollywood celebrities. Mentally disordered persons writing to public figures often mention and sometimes threaten public figures other than those to whom the letters are addressed, which raises important issues regarding notification of endangered third parties and the sharing of information among protective agencies.  相似文献   
109.
In the forensic science laboratory, the recovery of spermatozoa from vaginal swabs, or vaginal cells from penile swabs, can help determine if sexual intercourse may have taken place. There are several methods used to recover spermatozoa and cells from the swabs before visualisation on a microscope slide and most of these methods use water. Phosphate buffered saline (PBS) is a non-toxic solution used in many biological laboratories. Unlike water, PBS prevents cells rupturing or shrivelling up due to osmosis. This study demonstrates that PBS can be used for the extraction of spermatozoa and cells from swabs and that PBS does not affect subsequent DNA profiling.  相似文献   
110.
Bioaerosol data is often used in cases of building mold infestation alleging damage or adverse health effects upon occupants, despite the lack of consistent sampling and analytical protocols and numerical health-based standards. The most fundamental problem in these scenarios is defining a “significant” difference between a suspect indoor environment and the reference environment, regardless of the type of sampling and analysis utilized. Data interpretation focused upon differences in absolute numerical concentrations of fungi is subject to wide differences in expert opinion. On the other hand, an objective quantification of differences can be expressed in terms of probability and better meets criteria established in evidentiary rules.  相似文献   
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