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201.
Efficient capillary electrophoretic STR analysis requires rapid, reproducible and robust separation of DNA fragments with reasonable capillary longevity--this is currently accomplished using proprietary commercial polymeric sieving matrices specifically developed for this separation. These matrices, while effective, are costly and do not provide adequate resolution of STR DNA fragments in capillaries with shorter effective separation lengths, increasing the time required to accomplish the separation and minimizing the potential extrapolation to other miniaturized platforms. As the forensic community looks toward next generation microchip technology as a means of processing casework more rapidly, new sieving polymers need to be evaluated for utilization in this platform. The research presented here describes the assessment of commercially-available polymeric sieving matrices for STR analysis, with consideration given to feasibility of incorporation into a microdevice. Polymer composition, molecular weight, and concentration were evaluated, along with an assessment of the effects of buffer composition, separation temperature, and capillary length. These variables were evaluated individually or collectively on the ability to resolve STR DNA fragments and the reproducibility of the separations and the results compared to a proprietary commercial product. A 600,000 Da MW poly(ethylene oxide) (PEO) solution at a 3% (w/v) concentration was determined to be the most suitable matrix for these separations. This polymer, in coated capillaries, provided highly robust and reproducible separations, with near baseline resolution of fragments having single base differences. Reductions in the temperature of the separation, from 60 degrees C to 40 degrees C, and the urea concentration of the buffer, from 7 M to 3.5 M, provided increased longevity of the PEO polymer for repeated separations. Comparison of this polymer with currently specified commercial products used for STR analysis showed that the optimized PEO matrix provided superior separations under all conditions tested. In addition, PEO could be utilized in shorter capillary systems, with a concurrent decrease in analysis time, highlighting its potential for use in shortened capillary or microdevice systems. 相似文献
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Light, polarization, luminescent microscopy, phase contrast, special staining methods and scanning electron microscopy were used for studying sections and fragments of the endocardium and myocardium from 123 patients who had died of heart contusion and ischemic heart disease and from 50 rats with experimental heart contusion. The morphological classification of heart contusion and differential-diagnostic table of myocardial alterations due to contusion of the heart and ischemic heart disease are proposed to facilitate pathomorphological diagnosis of heart contusion. The classification of pathomorphological signs in heart contusion is presented. 相似文献
204.
Some causes of ineffective dental care because of the patient's negligence were analyzed. In 16 cases the patients ignored recommendations of the dentist and missed visits to the doctor. As a result, the patients developed complications leading to esthetic dissatisfaction, prolonged treatment, repeated prosthetic management. 相似文献
205.
This paper aims to review randomized experiments in criminology with offending outcomes and reasonably large numbers that were published between 1982 and 2004. A total of 83 experiments are summarized, compared with only 35 published between 1957 and 1981: 12 on policing, 13 on prevention, 14 on corrections, 22 on courts, and 22 on community interventions. Randomized experiments are still relatively uncommon, but there have been more large-scale multi-site experiments and replication programs. There have also been several experiments in which 100 or more places were randomly assigned. Relatively few experiments (only 10 out of 83) were conducted outside the United States. Meta-analyses suggest that prevention methods, correctional therapy, batterer programs, drug courts, juvenile restitution and deterrent policing were effective in reducing offending, while Scared Straight and boot camp programs caused a significant increase in offending. 相似文献
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Marx BP 《Journal of interpersonal violence》2005,20(2):225-230
The present article attempts to answer important questions about the most important thing learned from the past 20 years of research on sexual violence, the most important thing to be learned about sexual violence over the next 10 years, and the most promising methodological innovation in the study of sexual violence from the last 20 years. It is hoped that discussion of such important questions might further stimulate researchers and mental health professionals to continue making progress in our understanding of, as well as the struggle against, sexual violence. 相似文献
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UNEMPLOYMENT, SCHOOL LEAVING, AND CRIME 总被引:2,自引:0,他引:2