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941.
This work presents a novel collection method for gunshot residues (GSR) using a sampling procedure based on ethylenediaminetetraacetic acid (EDTA) solution as a complexing agent on moistened swabs. Detection was via a sector-field inductively coupled plasma mass spectrometry (HRICP-MS). The proposed collection and analytical method allowed detection of antimony (Sb), barium (Ba) and lead (Pb) after .38 shot tests. at detection limits of less than 1 microg L(-1) in four different areas of the hands of volunteers. This paper includes a discussion concerning hand areas near the thumb and forefinger as being more suitable for GSR collection as well as a comparison between differences observed using 2% diluted EDTA. 2% nitric acid solution, and simple deionized water as collecting solutions, proving the superior efficiency of EDTA in GSR recoveries.  相似文献   
942.
Supraphysiologic doses of testosterone are associated with increased aggression that is hypothesized to be a function of testosterone serum concentrations, mood, and personality. The study attempted to characterize this relationship among weightlifters who were users (n = 10) and nonusers (n = 18) of anabolic steroids. Participants were interviewed using the Modified Mania Rating Scale and Hamilton Rating Scale for Depression to assess mood, the Buss-Durkee Hostility Inventory (BDHI) and Point Subtraction Aggression Paradigm (PSAP) to assess aggression, and the Personality Disorder Questionnaire (PDQ-R) to assess personality. Blood samples were obtained for the determination of total, free, and weakly bound testosterone. Comparisons of continuous variables between testosterone users and non-users were performed with a parametric (unpaired t-test) or non-parametric (Mann-Whitney) test where appropriate. Correlations with testosterone were examined separately for testosterone users and non-users, using Spearman rank correlation. The subjective (BDHI) and objective (PSAP) assessments of aggression found that supranormal testosterone concentrations were associated with increased aggression. However, the PDQ-R results suggest that this finding was confounded by the personality disorder profile of the steroid users, because steroid users demonstrated Cluster B personality disorder traits for antisocial, borderline, and histrionic personality disorder.  相似文献   
943.
944.
The presence of cocaine in illicit drug samples is still being determined in some laboratories using spot tests and microcrystal tests. Seventeen chemical species were tested using three different spot tests (Wagner, Marquis, and cobalt thiocyanate followed by stannous chloride reactions) and two microcrystal tests (gold chloride and platinic chloride) to determine whether the results could be differentiated from the results of these tests on cocaine. The data obtained indicated that nine of the 17 compounds gave results similar to those from cocaine using the three spot tests, but that the results from microcrystal testing allowed for differentiation of all nine compounds from cocaine.  相似文献   
945.
The results of extraction of 1,2- and 1,4-dihydroxybenzene from water solutions by the hydrophobic and hydrophilic organic solvents are described. The influence of an extragent nature and of a water-phase pH medium on an extraction degree is demonstrated. The repetition factor needed to extract a preset quantity of examined compounds is calculated.  相似文献   
946.
947.
The case study was based on the osteologic collection of the chair for anthropology, State Moscow University, including the male carpal bones (67) and female carpal bones (13), aged above 18 to 20. Four measurements were made according to Martin's scheme for metacarpal bones and finger phalanxes. A diagnostic method was worked out on the bases of the discriminative analysis, with such method enabling the remodeling of the ordinal localization of metacarpal bones as well as of main, medium and distal phalanxes. The maximally accurate classification was ensured for metacarpal bones, ranging from 81.5% to 100%; and the minimally accurate one was achieved for distal phalanxes, ranging from 20% to 95%. The discriminative analysis results were checked for distal phalanxes by Neklyudov's series (male--100, female--85); they were described according to 7 sizes. However, an attempt to enhance the accuracy of the classification of these phalanxes failed. The offered method should be applied in combination with the traditional anatomic-and-morphological method; besides, if possible, it is necessary to check the congruence of joint surfaces in the metacarpal interphalangeal joints.  相似文献   
948.
A possibility was studied to use the plaster copies of skulls in the forensic medical identification of personality by applying the craniofacial method. No dependence was found between the plaster casts and the moulding types. Differences between the same craniometric sizes in the skull and in its cast are of an incidental nature. Such incidental deviation is related with an accuracy of determining the localization of craniometric points and with an instrumental precision of measuring devices. The necessity is substantiated that, while making a craniofacial examination, it is necessary to mark all anthropometric points in the skull cast, with the original being a control. The use of a plaster skull cast is possible in those cases, when the burial of the remains must be done in full.  相似文献   
949.
950.

Introduction

Introduction to special issue on professional insecurities  相似文献   
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