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81.
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Compulsory competitive tendering (CCT) has been an important instrument of Conservative government economic policy since 1979. Its effectiveness in generating cost-effective services depends on competition to supply the service in question.
The NHS domestic market is large and, prior to the introduction of CCT, promised to be profitable for contractors. Many contract cleaners with office cleaning experience entered. In the event the costs of entry were heavy, and the profit margins of established firms were reduced. When contracts have been awarded to firms, they tended to be to those with a track record. Many firms therefore withdrew; and the few that remained have profit margins in the NHS little different from those found elsewhere. Of more than by firms with a serious interest in entry, probably no more than a handful can have come out of the experience in net profit in the first seven years.
The experience of CCT in the market for NHS domestic services has shown that a degree of competition in the market can be achieved, arguably because of the presence of direct service organizations. Competition for this market, on the other hand, can be limited by the high costs of entry.  相似文献   
84.
The concentration of thyreoglobulin (tg) was determined for death caused by hanging, strangulation by ligature, and throttling. Cases of sudden death (traumatic aortic rupture, penetrating wounds of the heart) were used for comparison. The mean values in cases of hanging (149.9±202.3 ng/ml), strangulation by ligature (193.1±173.3), manual strangulation (561.6±173.9) are distinguishable from violent acute deaths (23.3±27.6) and living healthy individuals (17.3±16.1). By means of statistical comparisons, significant differences were found between throttling and strangulation by ligature and between throttling and hanging (adjusted P<0.001). In connection with examination of the bodies high tg values can be regarded as a vital reaction in obstructive asphyxia.  相似文献   
85.
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   
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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   
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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   
90.
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   
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