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111.
The aim of the study was to determine the enantioselective disposition of 3,4-methylenedioxymethamphetamine (MDMA) and other amphetamine-type stimulants (ATS) in segmented hair specimens of self-declared ecstasy abusers, who took part in a double-blind placebo-controlled six-way crossover study during approximately 7 weeks, during which they received a 75 and a 100 mg dose of racemic MDMA twice. Hair specimens were washed and cut into pieces of 2 cm length. After digestion and solid phase extraction, the enantiomers were derivatized with a chiral agent (2S,4R)-N-heptafluorobutyryl-4-heptafluorobutoyloxy-prolyl chloride, developed at the authors laboratory and quantified by gas chromatography coupled to mass spectrometry operating in the negative chemical ionization mode. Most of the hair specimens that were tested positive for MDMA showed a predominance of the (R)-enantiomer. The R/S ratios of MDMA varied between 1.02 and 2.75 and total concentrations ranged from 0.1 to 20.1 ng/mg. The enantiomers of its metabolite 3,4-methylenedioxyamphetamine (MDA) were also quantified in most hair segments. The R/S ratios of MDA varied between 0.60 and 1.60, while the concentrations of the enantiomers ranged from 10 to 160 pg/mg hair. When segmental analysis was performed on single hair specimens, no inversion of the R versus S ratios of MDMA and MDA was observed. The predominance of (R)-MDMA in hair was in accordance with those already published for other matrices. Furthermore, both enantiomers of amphetamine (AM) were also detected in hair segments of four volunteers and the R/S ratios ranged from 1.00 to 1.47.  相似文献   
112.
Haplotype and allele frequencies of the nine Y-STR (DYS19, DYS389 I, DYS389 II, DYS390, DYS391, DYS392, DYS393, DYS385 I/II) were determined in a population sample of 200 unrelated males from Belém, Brazil. The most common haplotypes are shared by 1.5% of the sample, while 186 haplotypes are unique. The haplotype diversity is 0.9995+/-0.0006. The data obtained were compared to those of other Brazilian populations. AMOVA indicates that 99.91% of all the haplotypical variation is found within geopolitical regions and only 0.09% is found among regions.  相似文献   
113.
This study concentrates on samples of bare pork skin, with and without bristles, and dried bovine ribs shot with a semi‐automatic pistol to find the best methodology and sampling surface in the search for inorganic gunshot residues (IGSR). Four quadrants of known surface areas were sampled at different distances from the bullet's hole with different swabs: tapes in graphite, Leukosilk® white tape, 3M® transparent tape, and a cotton swab to assess the technique able to collect the highest amounts of IGSR with the lowest contribution of the blank. The cotton swab wet in 10% HNO3 gave the best results. The highest amounts of IGSR, measured by ICP‐OES and MS, were detected on a surface of 3‐cm radius from the bullet's edge. The amount of metals collected decreased with the firing distance between 20 and 60 cm. The procedure was efficient for sampling different tissues like skin and bones.  相似文献   
114.
This study examined the extent and nature of cyberbullying in 23 Portuguese schools. A sample of 3,525 sixth-, eighth-, and eleventh-grade students completed a self-response questionnaire assessing their perceptions and experiences of cyberbullying. The findings showed that 7.6% of students have been victimized, and 3.9% have bullied others at least once over the last year. The incidences of victimization were higher for females and for the older students. In contrast, more boys reported having bullied others in the eleventh grade. The most frequent medium of cyberbullying was via websites, whilst sending offensive messages was the most widely reported type of behavior. Telling someone about cyberbullying is among the most frequent coping strategies used by cybervictims, who usually chose to tell their friends rather than adults. Implications of these findings for students, schools, and parents are discussed.  相似文献   
115.
The interpretation of pathology on skeletal remains is mandatory for implementing the biological profile and for disease recognition. Prostate cancer is one of the most common tumors, with a high preference for the skeleton as a primary site of metastasis. Its diagnosis on bone is however still ambiguous, due to its “osteoblastic” and resorptive manifestation. This study investigates distribution and appearance of prostate cancer metastases on dry bone on six known cases (selected from the Milano Cemetery Skeletal Collection) and one healthy individual. A macroscopic inspection was performed highlighting the abnormalities observed, describing location, shape, dimension, and aspect. A great amount of proliferative and mixed lesions was noticed, but also cases of pure lytic lesions were displayed. The multiple appearances of the manifestations observed display the difficulty in correctly identifying such a pathology, but also the potential and advantages provided by investigating a study sample with known antemortem history.  相似文献   
116.
Atherosclerosis is a chronic inflammatory disease creating calcifying plaques in the arterial walls. Because its paleopathological diagnosis remains little studied on skeletal remains, its impact on forensic and archeological data is completely underestimated. Here, 24 skeletal remains from the Milano Cemetery Skeletal Collection have been studied to evaluate the chance of atherosclerotic calcification survival, retrieval, and identification. Through direct comparison with a known autopsy collection and literature, the identification and categorization of several types of calcifications were performed. Clothing elements such as tights or socks played a definitive role in the preservation of the calcifications; hence they are more likely to be found in forensic cases than in archeological ones. Therefore, vascular calcifications are possible to collect and identify in skeletal remains if sufficient care is given to their recovery. Consequently and as markers of the disease, such identification can provide valuable pathological information for forensic and archeological cases.  相似文献   
117.
Abstract:  A frequently encountered task in the forensic scenario is verification of the human origin of severely degraded fragments of bone. In these cases histological methods which consider osteon size and morphology can prove to be useful. The authors in the present study verify the applicability of published algorithms to flat and subadult bones from human, dog, cat, cow, rabbit, sheep, pig, chicken, quail, and turkey samples. Metric analysis was performed on 2031 Haversian canals. Analyses carried out on human samples confirmed a success rate of around 70% on long adult bones; however the percentage of wrong answers was particularly high in the case of newborns and older subadults as well as on flat bones in general. Results therefore suggest that such regression equations should be limited only to bone fragments from long adult bones.  相似文献   
118.
The issue of juvenile pornography has seen an increase in the past few years of the number of expert opinions requested to forensic pathologists, paediatricians and other various experts within the forensic and medical fields concerning the age of represented individuals. Regardless of the entity of the problem, no actual method exists which can allow us to give an objective and scientific answer, particularly in the postpubertal stage. Using parameters related to sexual maturation can be very dangerous. Nonetheless some experts still insist with similar types of “expertises”. This study aims at verifying the ability of different experts in assessing age of postpubertal individuals represented in pornographic material. Results underline the difficulties and major uncertainties of age evaluation by visual observation of photographic material particularly when the subjects have reached the sexual maturation stage – and therefore in verifying whether the individual is above or below 18 years of age (an important age limit for most European countries as far as this type of crime is concerned). Furthermore the study stresses the need both to search for an alternate approach and to apply extreme caution in judicial evaluation.  相似文献   
119.
This article considers barriers and strategies for implementing performance budgeting in real-time application by a state-level government. The lessons learned from the State of New Jersey’s implementation of the Governor’s Performance Budgeting Initiative offer guidelines for public and nonprofit sector organizations attempting similar efforts. Data was gathered through a series of focus groups with key executive-level administrators. Observations and recommendations for enhancing and reenergizing current performance budgeting strategies for a state or agency are suggested.  相似文献   
120.
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