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751.
The purpose of this research was to explore different ways of using self-report data to derive measures of juvenile delinquent behavior. The subjects were 161 public school children in the Omaha area, and 1,030 public school children and 665 adjudicated delinquents in the metropolitan areas of Baltimore, Indianapolis, and Phoenix. The Omaha youths responded to twenty-eight self-report items two times with an intervening period of three weeks and then rated the items for seriousness. Four measures of delinquency were derived from the data: frequency of activity, diversity of activity, seriousness of activity, and progression into delinquent behavior. The four measures were shown to be highly reliable and strongly intercorrelated; none was shown to be consistently better than the other three. Rated seriousness and reported frequency of behavior were highly negatively correlated, giving support to the use of frequency measures in building delinquency scales. All four scales showed differences within the Omaha sample as a function of sex, age, and birth order; but the differences were not always in the same directions when the four measures were used. 相似文献
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This research explored the feasibility of using the degradation rate of deoxyribonucleic acid (DNA) in human rib bone to determine the time interval since death. Postmortem human rib samples were surface sterilized and incubated under sterile conditions in either high or low humidity conditions at room temperature for a period of weeks. At selected times, portions of the bone were cut away, and the DNA from these samples was extracted and subjected to strand separating gel electrophoresis. The DNAs in the gels were transferred to a nylon membrane, preserving their relative positions as in the gel, and probed with radioactive total genomic human DNA. Autoradiograms produced were scanned and digitized. When the samples were incubated under identical conditions, the degradation rate of DNA in samples from different individuals appeared very similar. The DNA degradation rate may vary with temperature and humidity more than it varies between individuals. 相似文献
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Robert K. Yin 《Policy Sciences》1977,8(4):381-399
This article reports on a study of technological innovations in state and local government agencies. The study was based on an aggregate analysis of 140 previously published and unpublished case studies, in which a closed-ended questionnaire was used to extract information from the case studies. The main hypotheses and findings of the study concern the possible existence of two innovative processes, one that emphasizes service improvements but that does not necessarily lead to enduring incorporation of the innovation (production efficiency), and the other that emphasizes incorporation even where the innovation may not have produced a demonstrable service improvement (bureaucratic self-interest).This study was supported in part by a grant from the Office of R&D Assessment, National Science Foundation, though the author alone is responsible for the views expressed here. 相似文献
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G K Murphy 《The American journal of forensic medicine and pathology》1988,9(3):255-257
On 21 February 1890, two woodsmen working in densely wooded Blenheim Swamp in southern Ontario, Canada, stumbled upon the dead body of a young Englishman who had been killed by two gunshot wounds to the head. He was identified as Frederick Benwell by a married couple, the Birchalls, who had traveled with him and another man, Pelly, from England to New York City by ship about 1 week before. The Birchalls lied regarding Benwell's subsequent movements. Questioning Pelly revealed to Detective John Murray that both Pelly and Benwell had replied separately to Birchall's advertisement for young men of means to become partners with him in a large Canadian farm, a deposit first being required. Birchall had been observed taking Benwell from Buffalo, New York, to Blenheim Swamp, for in reality there was no farm. There he had shot Benwell, leaving the body partially exposed. He then tried unsuccessfully to lure Pelly to his death in Niagara Falls. The Birchalls were arrested. Reginald Birchall was tried, convicted, and hanged. His attempt, including murder, to turn the so-called farm pupil colonization scheme to his own benefit had been frustrated by the dogged work of the master Canadian detective Murray. 相似文献