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41.
Postfeeding dispersal involves migration of larvae away from their food source in order to pupate. Puparia are difficult to find, yet are important for estimating PMI, and missing puparia during collection can result in inaccurate estimations. This study investigates the late season maggot dispersal patterns for blow flies at coyote carcasses in two habitats with an aim to improving puparia collection procedures. Puparia samples collected from various dispersal distances and directions tested the spatial distribution patterns of the various species using the variance/mean ratio (VMR). Lucilia illustris was the most common species to emerge, with a preferred minimum dispersal distance of more than 50.8 cm and an overall VMR value of 14.91, indicating this species had a clumped distribution pattern. These findings highlight that current collection procedures that use random sampling from under carcasses do not adequately account for the spatial distribution of larvae.  相似文献   
42.
在调研的基础上。本文分析了新阶段新形势提高统战干部素质的重要意义,归纳阐释了当前和今后一个时期统战干部素质的时代内涵,全面剖析了统战干部素质的现状及原因,并从保障机制、管理机制、评价机制、监督机制等四个方面.就进一步提高统战干部素质的对策和措施进行了积极探索。  相似文献   
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Earlier research has associated early puberty with emotional and behavioral symptoms particularly among girls, while among boys, findings have been contradictory as to whether risks are associated with early or late pubertal timing. We studied the association between pubertal timing and substance use behaviors in middle adolescence in a 2-year follow up study of 2,070 (mean age 15.5 years, SD 0.36; 56.4% females) Finnish adolescents. Pubertal timing was measured by age at menarche/oigarche. Eleven years or less was classified as early, 12–13 years as normative and 14 years or later as late pubertal timing. Substance use behaviors were elicited by a number of questions related to alcohol use patterns, smoking and cannabis use. As factors that could explain the association between pubertal timing and substance use, we studied depressive symptoms, delinquency and aggression, and parental monitoring. In boys, all these substance use behaviors were the more common the earlier the puberty and the associations persisted at age 17. Among girls, early pubertal timing was similarly associated with substance use behaviors at age 15, but no longer at age 17. The associations between pubertal timing and substance use behaviors persisted when symptom dimensions and parental monitoring were added into the models. Early puberty is a risk factor for substance use particularly among boys. Among girls, the impact of pubertal timing already tempers off during adolescence.  相似文献   
45.
We report the case of a 27 year old man who was injured by a Taser gun device which penetrated the frontal part of the skull and damaged the underlying frontal lobe. Cerebral penetration was revealed by a brain CT scan. A neurosurgical procedure was required to remove the dart from the skull and brain and the evolution was successful allowing discharge of the patient one week later. There were no additional lesions, particularly electrifying lesion, as only one probe had penetrated the skull. We also observed the length of a Taser dart is sufficient to allow brain penetration. Fortunately, no infection or neurological complication occurred following brain injury. This case study underlines the potential risk induced by the use of Taser stun gun. Although generally regarded as a safe alternative, serious injuries have however been reported and questions regarding the safety of the device still remains unresolved.  相似文献   
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47.
This study was aimed at determining the effect of seven blood enhancement reagents on the subsequent Profiler Plus fluorescent STR DNA analysis of fresh or aged bloody fingerprints deposited on various porous and nonporous surfaces. Amido Black, Crowle's Double Stain. 1,8-diazafluoren-9-one (DFO), Hungarian Red, leucomalachite green, luminol and ninhydrin were tested on linoleum, glass, metal, wood (pine, painted white), clothing (85% polyester/15% cotton, 65% polyester/35% cotton, and blue denim) and paper (Scott 2-ply and Xerox-grade). Preliminary experiments were designed to determine the optimal blood dilutions to use to ensure a DNA typing result following chemical enhancement. A 1:200 blood dilution deposited on linoleum and enhanced with Crowle's Double Stain generated enough DNA for one to two rounds of Profiler Plus PCR amplification. A comparative study of the DNA yields before and after treatment indicated that the quantity of DNA recovered from bloody fingerprints following enhancement was reduced by a factor of 2 to 12. Such a reduction in the DNA yields could potentially compromise DNA typing analysis in the case of small stains. The blood enhancement chemicals selected were also evaluated for their capability to reveal bloodmarks on the various porous and nonporous surfaces chosen in this study. Luminol. Amido Black and Crowle's Double Stain showed the highest sensitivity of all seven chemicals tested and revealed highly diluted (1:200) bloody fingerprints. Both luminol and Amido Black produced excellent results on both porous and nonporous surfaces, but Crowle's Double Stain failed to produce any results on porous substrates. Hungarian Red, DFO, leucomalachite green and ninhydrin showed lower sensitivities. Enhancement of bloodmarks using any of the chemicals selected, and short-term exposure to these same chemicals (i.e., less than 54 days), had no adverse effects on the PCR amplification of the nine STR systems surveyed (D3S 1358, HumvWA, HumFGA, D8S1179, D21S11, D18S51, D5S818, D13S317, D7S820) or of the gender determination marker Amelogenin. The intensity of the fluorescent signals was very similar and the allele size measurements remained constant and identical to those of untreated bloody fingerprints. No additional background fluorescence was noted. Continuous exposure (for 54 days) to two of the seven enhancement chemicals selected (i.e., Crowle's Double Stain and Hungarian Red) slightly reduced the amplification efficiency of the longer STR loci in profiles of fresh and 7 to 14-day-old bloodprints. This suggests that long-term exposure to these chemicals possibly affects the integrity of the DNA molecules. This study indicates that significant evidence can be obtained from fresh or aged bloody fingerprints applied to a variety of absorbent and nonabsorbent surfaces which are exposed to different enhancement chemicals for short or long periods of time. It also reaffirms that PCR STR DNA typing procedures are robust and provide excellent results when used in concert with fluorescence-based detection assays after fingerprint identification has taken place.  相似文献   
48.
Gang violence creates serious safety and security concerns in the community and prisons. Treated gang and nongang members recidivated significantly less in a 24-month follow-up than their untreated matched controls. Treatment consisted of high intensity cognitive-behavioral programs that follow the risk, need, and responsivity principles (Andrews & Bonta, 2003). The treated gang members who recidivated violently after treatment received significantly shorter sentences (i.e. they committed less serious offences) than their untreated matched controls. Untreated gang members had significantly higher rates of major (but not minor) institutional offences than the other three groups. Correctional treatment that follows the risk, need and responsivity principles appears able to reduce recidivism and major institutional misconduct. Effective correctional treatment should be considered as one of the approaches in the management and rehabilitation of incarcerated gang members.  相似文献   
49.
This article presents the results of research investigating the relation between interpersonal factors and personality disorders and intra-familial versus extra-familial child molesters. The sample contained 41 intra-familial and 43 extra-familial child molesters as well as a matched comparison group of 80 subjects. The analysis of the research results show that interpersonal factors, such as parental sensitivity, trust, and adult romantic attachment, discriminate between intra-familial and extra-familial child molesters. These findings structure the heterogeneous field of child molesters, as intra-familial child molesting seems to be related to relational attitude as well as personality disorders, whereas extra-familial child molesting is mainly related to personality disorders without showing significant deficits in the interpersonal factors that were measured. These results contribute to the explanation of this deviant sexual conduct and to the development and differentiation of the treatment of child molesters.  相似文献   
50.
A preliminary study was conducted to assess the capability of a new alcohol-based tissue fixative, GenoFix, to preserve DNA from biopsy tissues stored at room temperature and/or -20 degrees C in a freezer, for subsequent short tandem repeat (STR) DNA typing analysis. Fresh human smooth muscle samples were stored at room temperature in GenoFix for one month and up to one year and seven months before being processed using the megaplex STR systems, AmpFlSTR Profiler Plus and AmpFlSTR COfiler. Alternatively, muscle tissues in GenoFix were placed at -20 degrees C in a freezer for up to 3 1/2 years following two to three months in the fixative at room temperature. DNA analysis was also carried out on tissues stored in GenoFix for one month at room temperature and subsequently paraffin-embedded and stored at room temperature for four years. The AmpFlSTR Profiler Plus and AmpFlSTR COfiler STR profiles produced, using DNA extracted from all fixed tissue samples, were of very good quality. The fluorescent signals were well balanced across the nine STR loci or six loci comprised in the megaplexes surveyed and profiles showed no differences with those observed for the control blood of the respective donor patients. Continuous exposure to GenoFix at room temperature (up to one year and seven months) did not compromise the STR typing analysis of the fixed tissues. No adverse effects were noted on the STR typeability of tissues fixed with GenoFix and stored at -20 degrees C in a freezer for up to 3 1/2 years. STR profiles generated from the paraffin-embedded tissues fixed in GenoFix were of excellent quality. This preliminary study suggests that GenoFix can be used to store tissue samples at room temperature for up to one year and seven months or at -20 degrees C in a freezer for longer storage (up to 3 1/2 years). This new and odorless tissue fixative promotes tissue and DNA preservation in a very effective manner and as such may prove useful in criminal investigations or mass disaster identifications carried out in remote locations and in which a small or large number of tissue samples are collected for further analyses.  相似文献   
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