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971.
An experimental study was done to determine the diameter and velocity of blood drops falling on a surface by measuring the size of bloodstains they produced and counting the number of radial spines projecting from them. Bloodstains were formed by releasing drops of pig blood with a range of diameters (3.0-4.3 mm) and impact velocities (2.4-4.9 m/s), onto four different flat surfaces (glass, steel, plastic, paper) with varying roughness (0.03-2.9 microm). High-speed photography was used to record drop impact dynamics. Bloodstain diameters and the number of spines formed around the rim of stains increased with impact velocity and drop diameter. Increasing surface roughness reduced stain diameter and promoted merging of spines, diminishing their number. Equations are presented that explicitly relate drop diameter and impact velocity to measurements of stain diameter and number of spines.  相似文献   
972.
The purpose of this study was to determine the precision and accuracy of facial soft tissue measurement using personal computer (PC)-based multiplanar reconstructed (MPR) computed tomography (CT) images and to evaluate the effect of the various CT scanning protocols on the facial soft tissue thickness measurement. Thirteen different CT imaging protocols were used to image a cadaver head. MPR reformations and three-dimensional (3D) reconstructions viewed on a laptop PC were used to make measurements at six specific sites on each set of images. These measurements were compared to physical measurements at the same sites. Increasing the slice thickness resulted in decreased image quality. Within the same slice thickness, increasing the pitch ratio in the spiral mode, resulted in decreasing image quality. The image quality of conventional CT scanning was relatively poorer than that of the spiral CT scanning. However, the mean deviation from the physical measurement was within 0.43 mm in every instance. This mean deviation was quite small and clinically acceptable for measuring the soft tissue thickness of the facial area. PC-based MPR CT images of the face using routine scanning CT protocols can be used to accurately measure soft tissue thickness in the facial region. However, for more fine and accurate data collection, scanning protocols with slice thicknesses less than 5mm, and a spiral/helical mode pitch less than 2:1 are recommended.  相似文献   
973.
Allele frequencies for the nine tetrameric short tandem repeats (STR) loci D3S1358, vWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317, D7S820 (AmpFlSTR) Profiler Plus PCR Amplification kit, PE Applied Biosystems) were determined in 109 unrelated Korean ethnic group individuals from northeast China.  相似文献   
974.
Using a simulated civil case, this experiment investigated whether mock jurors: (a) are able to disregard hearsay evidence when admonished to do so, (b) experience psychological reactance and "backfire effects" in proportion to the strength of judicial admonition instructing them to disregard hearsay evidence, and (c) are able to recognize and disregard hearsay evidence without judicial instructions. Results indicate that jurors were unable to disregard inadmissible hearsay testimony in some legal decisions regardless of whether there were judicial instructions to do so. Jurors exhibited backfire effects paying more attention to inadmissible hearsay evidence when they were strongly instructed to disregard it. More specifically, juror backfire effects were evident in both their confidence in their liability verdicts and in their punitive damage awards. The legal and policy implications of these findings are discussed.  相似文献   
975.
The Self-Appraisal Questionnaire (SAQ) is a 72-item self-report measure designed to predict violent and nonviolent recidivism among adult criminal offenders. The results from using samples from Australia, Canada, England, Singapore, and two samples from the United States (North Carolina and Pennsylvania) indicated that (a) the SAQ has sound psychometric properties, with acceptable reliability and concurrent validity for assessing recidivism and institutional adjustment; (b) there were no significant differences among the scores of the White, African American, Hispanic, and Aboriginal Australian offenders on the SAQ; (c) there were no significant differences among offenders who completed the SAQ for research purposes versus offenders who completed it as part of a decision-making process. Results provided support for the validity of the SAQ to be used with the culturally diverse offenders involved in this research and provided further evidence that contradicts concerns that the SAQ as a self-report measure may be susceptible to lying, and self-presentation biases.  相似文献   
976.
Sharing knowledge and information is an important factor in the discourses on electronic government, national security, and human capital management in public administration. This article analyzes the impact of organizational context and IT on employees' perceptions of knowledge-sharing capabilities in five public sector and five private sector organizations in South Korea. Social networks, centralization, performance-based reward systems, employee usage of IT applications, and user-friendly IT systems were found to significantly affect employee knowledge-sharing capabilities in the organizations studied. For public sector employees, social networks, performance-based reward systems, and employee usage of IT applications are all positively associated with high levels of employee knowledge-sharing capabilities. Lessons and implications for knowledge-sharing capabilities and management leadership in the public sector are presented.  相似文献   
977.
A new set of multiplexed PCR primers has been applied to the analysis of human skeletal remains to determine their efficacy in analyzing degraded DNA. These primer sets, known as Miniplexes, produce shorter amplicons (50-280 base pairs (bp)) than standard short tandem repeat (STR) kits, but still utilize the 13 CODIS STR loci, providing results that are searchable on national DNA databases. In this study, a set of 31 different human remains were exposed to a variety of environmental conditions, extracted, and amplified with commercial and Miniplex DNA typing kits. The amplification efficiency of the Miniplex sets was then compared with the Promega PowerPlex 16 system. Sixty-four percent of the samples generated full profiles when amplified with the Miniplexes, while only 16% of the samples generated full profiles with the Powerplex 16 kit. Complete profiles were obtained for 11 of the 12 Miniplex loci with amplicon sizes less than 200 bp. These data suggest smaller PCR amplicons may provide a useful alternative to mitochondrial DNA for anthropological and forensic analysis of degraded DNA from human skeletal remains.  相似文献   
978.
Examination of stomach contents is one of the important steps in medical legal autopsy. Vegetative materials such as stems, roots, and seeds in stomach contents can be valuable evidence for providing investigative leads in death investigation. Currently, the identification of plant materials relies on microscopic and morphologic examination. We have found that many seeds are often protected from acid degradation during stomach digestion by their tough exterior seed coat. Tomato seeds were selected as a model system to assess DNA analysis and plant variety marker identification. The DNA-amplified fragment length polymorphism method was performed to determine if the DNA obtained from single seeds could be used for PCR analysis. From the amplified fragment length polymorphism results, some candidate markers for individualizing seeds from morphologically distinct tomatoes were identified. These data on DNA analysis of tomato seeds indicate amplified fragment length polymorphism is a viable procedure for the individualization of seeds from stomach contents in forensic investigations.  相似文献   
979.
Dextromethorphan (DMP), an antitussive, is one of the most popular drugs among the younger generation in Korea. It usually is taken for its hallucinogenic properties and overdoses have been responsible for the fatalities that have been reported frequently. To control the abuse of DMP, the authorities restricted its use through classifying it as a controlled drug on October 2003. The purpose of this study is to provide a standard method for the analysis of DMP and its main metabolite, dextrorphan (DTP) in biological specimens. At first we established a standard operating procedure (SOP) for DMP/DTP in urine, and a method validation was performed. We also quantified DMP from 16 drug abuser's urine samples all of which were positive in the screening test for DMP. For the detection of DMP/DTP, urine samples were adjusted with 6N NaOH (pH 11) and extracted with ethylacetate. Thin layer chromatography was used as the screening test, and the final identification for DMP/DTP was used by GC/MS. The ions (m/z 271 for DMP, m/z 257 for DTP and m/z 86 for lidocaine as internal standard) were extracted from the full scan mass spectrum and were used for quantification. The selectivity, linearity of calibration, accuracy, within- and between day precision, limit of detection and quantification, recovery and stability were examined as parts of the method validation. Extracted calibration curves were linear from 100 to 2000 ng/mL for DMP and DTP with correlation coefficients better than 0.999. Limit detection was 50 ng/mL for DMP and DTP. Within-run precision (%CV) for DMP and DTP at three different concentrations (100, 500 and 1000 ng/mL) was 6.10-18.85%, and between-run precision was 1.70-7.86% for DMP and DTP. Absolute recovery for DMP and DTP was 57-74%, and relative recovery (extraction efficiency) was 80-89%. For 16 drug abuser's urine samples, the concentrations of DMP and DTP were 0.16-52.63 and 0.41-23.75 microg/mL, respectively. Method validation is an important requirement in the practice of chemical analysis, and it will be particularly useful in verifying the reliability of analytical results in the field of forensic science.  相似文献   
980.
The relative effectiveness of two interventions for dealing with 200 court-referred spousal abusers is examined. The overall failure rate is 17.5%, with most recidivism occurring during the first 6 months after treatment. Offenders who completed a 14-week group treatment program called SAFE manifest significantly lower rates of recidivism (10.6%) than do offenders who did not complete the mandated treatment (38.8%). Some high-risk clients are referred to a cognitive restructuring treatment program called R&R, and those completing both programs (despite their high-risk status) have a recidivism rate of only 23.5%. Prediction of recidivism is difficult, with the LSI-R scores correctly predicting only 66% of the outcomes, using a cut score of 11.5. The exploration of other predictors is encouraged.  相似文献   
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