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161.
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   
162.
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   
163.
With the rapid growth of cross-border competition among currencies, informed observers predict that the new monetary unions are virtually inevitable in many parts of the world. In fact, predictions of such alliances are misleading and almost certainly wrong. Monetary unions necessarily imply a measure of collective action in the issue and management of money. An alliance requires allies—other states with similar preferences and a disposition to act cooperatively. A survey of proposed monetary unions shows that willing partners among sovereign states are just not all that plentiful. Conceivably some governments could be attracted to less demanding forms of monetary alliance, depending on bargaining context. But prospects for many full new monetary unions are dim at best.  相似文献   
164.
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   
165.
Despite its original purpose to protect and rehabilitate wayward children, the juvenile system has grown more punitive and has embraced the use of harsher punishments, including execution, for juvenile offenders. Relatively little is known, however, about public attitudes toward the use of capital punishment for juveniles. This research explored the determinants of death penalty opinion, identified the minimum age at which respondents were willing to allow a juvenile to be put to death and examined the willingness of respondents to support an alternative sentence of life without the possibility of parole (LWOP). The results suggested that, while one-quarter of the sample was willing to execute juveniles who were fifteen and under at the time of the crime, there was less support for the execution of juveniles than of adults. In addition, of those who supported the use of the death penalty for juveniles, almost one-half would support LWOP as an alternative to the death penalty.  相似文献   
166.
Recent studies point to the potential theoretical and practical benefits of focusing police resources on crime hot spots. However, many scholars have noted that such approaches risk displacing crime or disorder to other places where programs are not in place. Although much attention has been paid to the idea of displacement, methodological problems associated with measuring it have often been overlooked. We try to fill these gaps in measurement and understanding of displacement and the related phenomenon of diffusion of crime control benefits. Our main focus is on immediate spatial displacement or diffusion of crime to areas near the targeted sites of an intervention. Do focused crime prevention efforts at places simply result in a movement of offenders to areas nearby targeted sites—“do they simply move crime around the corner”? Or, conversely, will a crime prevention effort focusing on specific places lead to improvement in areas nearby—what has come to be termed a diffusion of crime control benefits? Our data are drawn from a controlled study of displacement and diffusion in Jersey City, New Jersey. Two sites with substantial street‐level crime and disorder were targeted and carefully monitored during an experimental period. Two neighboring areas were selected as “catchment areas” from which to assess immediate spatial displacement or diffusion. Intensive police interventions were applied to each target site but not to the catchment areas. More than 6,000 20‐minute social observations were conducted in the target and catchment areas. They were supplemented by interviews and ethnographic field observations. Our findings indicate that, at least for crime markets involving drugs and prostitution, crime does not simply move around the corner. Indeed, this study supports the position that the most likely outcome of such focused crime prevention efforts is a diffusion of crime control benefits to nearby areas.  相似文献   
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