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541.
542.
With longitudinal data from a sample of 359 adolescent offenders, we tested three measures of social bonding (conventional moral belief, attachment, and commitment/involvement) and deviant peer association as outcomes of low self-control and as mediators of the effect of low self-control on juvenile offending. Low self-control was negatively related to each bonding measure, positively related to deviant peer association, and positively related to offending at follow-up. Its effect on offending was fully mediated by conventional moral belief and attachment. These results provide modest support for a combination of self-control and social bonding perspectives on juvenile offending.  相似文献   
543.
The PowerPlex 16 BIO multiplex short tandem repeat (STR) system contains the 13 CODIS loci (FGA, TPOX, D8S1179, vWA, D18S51, D21S11, TH01, D3S1358, CSF1PO, D16S539, D7S820, D13S317, and DS5S818), plus two pentanucleotide repeat loci (Penta D and Penta E) and the sex-identifying locus. Amelogenin. The PowerPlex 16 BIO System is optimized for use with the Hitachi FMBIO gel imaging systems. A consortium of seven independent laboratories collaborated to perform the studies defined by the FBI standards for performing a developmental validation, including the evaluation of sample concordance, percent stutter determination, nonprobative casework, precision, sensitivity, mixture determination, effect of substrates, the impact of environmental insults, and species specificity. All samples tested for concordance were consistent except for one sample from the Virginia Division of Forensic Science database that displayed discordance at D13S317, a locus whose primer sequence was altered. Stutter values were comparable to those of other STR multiplex systems, the precision was comparable to other multiplexes analyzed by gel electrophoresis, the DNA profiles were unchanged by the substrate upon which the blood samples were placed, and the nonprobative casework samples re-typed for the PowerPlex 16 BIO System were consistent with previous typing results. When greater than 0.125 ng of DNA was placed into the PowerPlex 16 BIO System amplification reaction, a full profile was generated by all laboratories. The mixture study results were comparable to those reported for other multiplex systems, the environmental study demonstrated a loss of larger molecular weight loci when samples were incubated at elevated temperatures for a prolonged period of time, and the only notable cross species hybridization was observed with primate DNA samples. This extensive validation work performed demonstrates that the PowerPlex 16 BIO System provides STR data of a quality comparable with other PowerPlex STR multiplex kits as well as other widely used STR multiplexes and is thus suitable for evidentiary casework analysis as well as database sample profiling.  相似文献   
544.
545.
Protein radioimmunoassay (pRIA) offers the potential to identify species in small skeletal fragments submitted as forensic evidence. The technique consists of protein extraction followed by a solid-phase double-antibody radioimmunoassay using controls of antisera (raised in rabbits) and radioactive (iodine-125) antibody of rabbit gamma globulin (produced in donkeys). Species determination results from evaluation of radioactivity uptake. To demonstrate the potential of this technique, six known bone samples (three human and three nonhuman, including one from a deer [Odocoileus virginianus]) were submitted for blind analysis. pRIA correctly distinguished the human from the nonhuman samples. Using 200 mg or less of each sample, species of the deer specimen was identified correctly, given the choices of cow, deer, dog, goat, and pig.  相似文献   
546.
Identification criteria, specifically discriminant function formulae derived from traditional craniometrics, currently used in South Florida for Cuban Americans and other "Hispanic" groups, are unsuitable to provide adequate biological profiles due to complex biological histories as well as widely diverse geographic origins. Florida's total population is approximately 16 million (15,982,378) individuals. Of the total population 2.682,715, or 16.8%, are self-identified as "Hispanic". South Florida (herein defined as Miami-Dade, Broward and Collier Counties) is home to 60% of the total Hispanic population of Florida with 1,291,737 (48.15%) residing in Miami-Dade County. The Hispanic population of Miami-Dade County makes up 57.0% of the total population of 2,253,362. Each recognized sub-group of Hispanics (Mexican, Puerto Rican, and Cuban) includes its own geographic point-of-origin and population history. Cuban-Americans (arriving in the late 1950's and early 1960's) make up the largest sub-population of Florida's Hispanics in any county and in Miami-Dade number 650,601 or 51% of the total Latin population. Additionally, as in other agricultural states, Florida has a very large population of undocumented workers who primarily arrive from Texas and points south of the Straits of Florida. Thus the application of the available traditional craniometric and non-metric methods are not appropriate for South Florida's Latin population. To begin to address this issue in relation to South Florida's Cuban population, we present an analysis of cranio-facial shape variation in a 19th Century Cuban sample, 17th Century Spanish sample, a Precontact Cuban sample, and Terry Blacks using geometric morphometric methods. Significant biological shape differences and patterns of variation are observed among the groups. These results provide us with a context in which to begin to understand the biological variation of Cuban Americans, which will enable the development of identification criteria specific for this U.S. hybrid Hispanic community.  相似文献   
547.
This article reports initial findings from a study of middle grades educational reforms in Philadelphia. We use multilevel change models to analyze the impact on student mathematics achievement of privatization through the use of educational management organizations (EMOs), taking account of the structural reforms (creation of new K‐8 schools to replace selected middle schools) occurring simultaneously within the district. Overall, the longitudinal mathematics achievement gains for students in EMO‐managed schools were not larger than those for students in schools managed by the district. Non‐Edison EMO schools actually performed worse than district‐managed schools. With the exception of one older K‐8 school in one cohort, Edison schools did not significantly outperform district‐managed counterparts. Students in long‐established K‐8 schools generally outgained students in middle schools, but gains were not as large in newly‐established K‐8 schools. Across all types of schools, the second cohort of students obtained greater gains than did the first.  相似文献   
548.
The submission to forensic laboratories of unknown specimens suspected of being biological or chemical warfare agents has increased tremendously with the threat of terrorism. Oftentimes, a threatening correspondence that contains hoax materials is intended to make the recipient(s) believe they have been exposed to a toxin. In some cases, the perpetrator can use standard household products, such as detergents and soaps. Once these materials are received, they become forensic evidence and may be analyzed for identification and/or comparison with known seized material from a suspect(s). Two separate studies were conducted using different analytical protocols for bar soaps. In the first set, the forensic laboratory at the United States Secret Service conducted tests on 68 bars of soap using solid-phase microextraction and gas chromatography coupled with mass spectrometry. The 68 different soaps displayed unique total ion chromatogram profiles. Energy-dispersive X-ray analysis in conjunction with scanning electron microscopy was also used to characterize 46 of the 68 soaps as a preliminary study. In a second set of studies, as part of a homicide investigation, the laboratory at the California Department of Justice, Riverside, conducted examinations on 13 bars of soap by utilizing Fourier transform-infrared spectroscopy. The case study demonstrated that it is possible to distinguish some bar soaps using infrared analysis. Furthermore, the bar soaps could be distinguished from typical laundry detergents using this technique.  相似文献   
549.
The authors investigated the effect of giving written material on information recall from informed consent counselling for cataract surgery. Fifty English-speaking patients who underwent non-urgent cataract extraction at Flinders Medical Centre, South Australia, were prospectively enrolled. Systematic counselling for cataract surgery was provided, with a written copy of the content given to a randomly selected group of patients (n = 24). All subjects completed a questionnaire after counselling and again at two weeks after surgery to test their satisfaction with, and recall of, information provided. Patients were found to be satisfied with the amount of information they received and most were able to recall details about the cataract surgery procedure. However, many could not recall success rates or complication rates and only a minority could list any complication. The provision of written information did not significantly alter recall (p>0.05). Recall was significantly better immediately after counselling than two weeks after surgery (p<0.05). Younger patients also had significantly better recall (p<0.05). Patients were happy with the information they had been given but did not remember enough from the informed consent process to satisfy legal requirements.  相似文献   
550.
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