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881.
ABSTRACT: Determination of the time of death is an important consideration in forensic practice. Many methods have been attempted to accurately and systematically determine the postmortem interval (PMI). Histologic examination of the skin or appendages is one of the methods tried by few researchers. However, no attempt had been made to analyze the histologic changes in the skin and appendages simultaneously and to compare them with PMI. We sequentially studied the histologic changes of the skin and appendages in the early PMI. The results of the present study show that the skin undergoes progressive morphological changes in the postmortem period. The epidermis and the dermis appeared normal for 6 hours after death, and after this period, degenerative changes began. By 6 to 9 hours after death, degeneration began in the dermis, and by the end of 18 hours, the dermis began to disintegrate. The sweat glands appeared normal for approximately 3 to 4 hours. For 18 hours after death, the sebaceous glands and hair follicles appeared normal, and after this period, degeneration began.  相似文献   
882.
A number of dyed acrylic and acetate fibre samples were examined with plane polarized light on their dichroic behavior by optical light microscopy (OLM) and microspectrophotometry with plane polarized light (MSP-PPL). It was found that most of these low birefringent fibres possess weak dichroic effects that are very hard to observe with microscopy. However, using MSP-PPL, the linear dichroism could be measured. A comparison between the dichroic effects found for the same disperse dyes on triacetate (TrAc), diacetate (Ac), polyester (PES) and polyamide (PA) shows that the linear dichroism follows the order: PA>PES >TrAc, Ac.  相似文献   
883.
Significant needs exist for increased and better substance abuse treatment services in our nation's prisons. The TCU Organizational Readiness for Change (ORC) survey has been widely used in community-based treatment programs and evidence is accumulating for relationships between readiness for change and implementation of new clinical practices. Results of organizational surveys of correctional counselors from 12 programs in two states are compared with samples of community-based counselors. Correctional counselors perceived strong needs for new evidence-based practices but, compared to community counselors, reported fewer resources and less favorable organizational climates. These results have important implications for successfully implementing new practices.  相似文献   
884.
近年来网络犯罪数量呈快速上升的势头,但是却缺乏一种有效的取证方法来处理这些案件.调查人员通常依靠调查大量繁琐的源代码来了解犯罪模型及提取证据,但这种方式需要很多的人力与时间,并可能导致人为错误.为了克服调查人员可能出现的这些潜在错误,我们在本文中提出了一种半自动的方法来解决这些问题.该方法集成了用户视图(基于取证调查人员的高级别研究)和系统视图(基于对源代码的自动分析),来帮助调查人员精确调查的范围.本文应用此方法分析了一个真实案件,证明了方法的可行性,同时帮助调查人员高效地确定了调查范围和犯罪模型.可见这种半自动方法可以对大量有多个来源的电子证据进行有效分析,提高了网络犯罪案件取证的效率和可靠性.  相似文献   
885.
Abstract: This study provides forensic search teams with systematic geophysical monitoring data over simulated clandestine graves for comparison to active cases. Simulated “wrapped” and “naked” burials were created. Multigeophysical surveys were collected over a 3‐year monitoring period. Bulk ground resistivity, electrical resistivity imaging, multifrequency ground‐penetrating radar (GPR), and grave and background “soil‐water” conductivity data were collected. Resistivity surveys revealed the naked burial had consistently low‐resistivity anomalies, whereas the wrapped burial had small, varying high‐resistivity anomalies. GPR 110‐ to 900‐MHz frequency surveys showed the wrapped burial could be detected throughout, with the “naked” burial mostly resolved. Two hundred and twenty‐five megahertz frequency GPR data were optimal. “Soil‐water” analyses showed rapidly increasing (year 1), slowly increasing (year 2), and decreasing (year 3) conductivity values. Results suggest resistivity and GPR surveys should be collected if target “wrapping” is unknown, with winter to spring surveys optimal. Resistivity surveys should be collected in clay‐rich soils.  相似文献   
886.
Anomie is a highly prominent theoretical construct in macro-social, particularly cross-national, criminological inquiry. Yet despite its prominence, it has proven to be quite elusive with regard to its measurement and, hence, making it nearly impossible to test theoretical hypotheses regarding its predictive efficacy. Although the concept, whether derived from Merton's classic conceptualization or from its current incarnation in the form of institutional anomie as developed by Messner and Rosenfeld, is multidimensional and complex in its theoretical structure, most researchers have attempted to operationalize it through simple, single-item, often surrogate/proxy measures. The present research note attempts to develop a measure that is more consistent with its multidimensional and complex nature. This more complex operationalization is then examined with regard to its efficacy at predicting cross-national levels of both homicide and theft. Our results suggest that that this new operationalization has considerable predictive efficacy, accounting for approximately one third of the variation in the cross-national level of both homicide and theft.  相似文献   
887.
The easily available "legal highs", which are products containing psychoactive substances, such as cathinones, piperazines and synthetic cannabinoids, are abused by adolescents in Poland and in the world as alternatives to classic drugs, such as amphetamines or marijuana. The majority of these potentially dangerous substances are still legal and they are associated with a risk of severe poisoning or even death, and provide new challenges in clinical and forensic toxicological practice. Investigations in the field of "designer drugs" may be well illustrated by the case of a suicide of a 21-year old male who ingested a specified dose of a preparation called "Amphi-bi-a" that contains bk-MBDB, chemically 2-methylamino-1-(3,4-methylenedioxyphenyl) butan-1-one, which belongs to the cathinone group, as a synthetic euphoric empathogen and psychoactive stimulant that is chemically similar to MDMA. It is one of more common components of "legal highs" examined in Poland and other countries. The documentation of the case includes a clinical assessment of the patient's health status performed during his almost 4-h hospitalization before death, autopsy and histological examinations supported by toxicological findings revealing bk-MBDB at extremely high concentrations (at 20mg/l in the blood and 33mg/kg in the liver); hence, this body of evidence contributes to knowledge in the field of "designer drugs". Inventions of designers of new psychoactive xenobiotics, which are much in demand, especially in view of the dynamic Internet marketing, which drums up narcobusiness, must be balanced by a national strategy developed by medical, legal and educational circles in the modern civilized world in order to prevent the spreading of the phenomenon.  相似文献   
888.
Mephedrone is a synthetic derivative of cathinone which is becoming more common on the recreational drug market. Several intoxications following mephedrone abuse have been reported though published papers have focused essentially on analytical approaches for biological fluids and only one has involved a hair sample. After the development and validation of a new method, the first series of positive results for mephedrone in hair specimens is reported here. After decontamination of the hair strand in methylene chloride, hair segments were cut into small pieces with scissors, weighed and incubated overnight in Soerensen buffer pH 7.0 in the presence of deuterated 3,4-methylenedioxymethamphetamine (MDMA) at 40°C. The incubation medium was extracted using ethyl acetate after alkalinisation with 1N sodium hydroxide (NaOH). Before injection, the dry extract was derivatized using a mixture of heptafluorobutyric anhydride/ethyl acetate (100:50, v/v), evaporated and dissolved in ethyl acetate (25μl). After introduction of 1μl of the extract onto a splitless injector, chromatographic separation was achieved on a HP 6890 gas chromatograph equipped with a 5-MS capillary column. Detection was achieved in single ion monitoring mode (m/z 254-119-210 for mephedrone, m/z 258-213 for MDMA-d5) using a 5973 MSD operating in electron impact mode. Sixty-seven hair specimens were tested for mephedrone. Thirteen of them were found positive for mephedrone with concentrations ranging from 0.2 to 313.2ng/mg with a mean concentration of 26.8ng/mg. It was difficult to compare our findings due to a lack of reference data, nevertheless mephedrone seems well incorporated into hair (concentrations in the ng/mg range) like other stimulant drugs such as amphetamines or cocaine. The aim of this work was to develop a specific and accurate method for mephedrone analysis in hair specimens and its application to a large number of samples (n=67). The developed analytical method appears sensitive enough to reveal occasional to regular use of mephedrone.  相似文献   
889.
A 2010 UK police search for a clandestine burial highlighted the need for more information and quantitative data to aid coastal beach searches. This study aimed to address this by establishing relevant forensic search methodologies to aid the search for clandestine coastal burial sites, using the North West English coastline as a search area. A set of parameters were established, including criteria such as tidal range, proximity to vehicular access points and distance from inhabited areas, which may inform forensic searches by prioritising likely locations of clandestine burials. Three prioritised coastal locations were subsequently identified: (1) coastal dunes at Formby, (2) coastal dunes and (3) beach foreshore at Southport, all sites part of the Liverpool City Region in the United Kingdom. At all locations, simulated clandestine graves were hand-dug by spades into which a naked adult-sized, metal-jointed fiberglass mannequin was buried at 0.5 m below ground level. Trial geophysical surveys were then undertaken with the aim of identifying the optimal geophysical instrumentation and technique to deploy in such environments. GPR data showed 450 MHz frequency antennae to be optimal, with significantly poor data obtained from the foreshore area due to saline seawater. Electrical resistivity and magnetic susceptibility surveys were successful in coastal environments in target detection (albeit not in non-vegetated sand dunes), with resistivity fixed-offset configurations deemed optimal. The latter survey successes may be due to the recent disturbed 'grave' rather than the target, which itself is of interest in terms of identifying the most recent clandestine burials.  相似文献   
890.
Although proprietary medicines and decoction of processed aconite roots are the most widely used, tincture accounts for the great majority of aconite poisoning cases in China, indicating that it is much more toxic than other formulations. Aconite tincture is often self-prepared at home and raw aconite plants or roots are often used. Even if processed aconite roots were used to make the tincture, the amount of Aconitum alkaloids is highly variable, depending on the adequacy of processing and quality control. Aconitum alkaloids dissolve efficiently in alcohol. For these reasons, tincture contains very high concentrations of Aconitum alkaloids. Despite its high intrinsic toxicity, overdose of aconite tincture by the users has been common. Severe aconite poisoning can be complicated by fatal ventricular tachyarrhythmias and asystole. The public should be repeatedly warned of the danger of taking aconite tincture by mouth.  相似文献   
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