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931.
932.
Schlesinger LB 《Journal of forensic sciences》2001,46(5):1119-1123
A case of an independent professional contract murderer, who killed over 100 people, is reported. After eluding law enforcement for 30 years, the subject killed several associates who he believed could implicate him in various crimes. These homicides eventually led to his arrest, since the victims were individuals who could be linked to him. This hit man had a background of poverty and childhood abuse but, as an adult, had pursued a middle-class lifestyle and kept his family totally separate from his criminal career. In addition, he had a number of characteristics that helped him carry out his crimes in a highly planned, methodical, and organized manner: he had adept social judgment; personality traits of orderliness, control, and paranoid vigilance; useful defense mechanisms of rationalization and reframing; and an exceptional ability to encapsulate emotions. This case is discussed within the context of contract murder, a crime that occurs relatively frequently and is probably increasing; yet it often goes undetected, the arrest rate is low, and the offender is rarely studied. 相似文献
933.
Negrusz A Moore CM Hinkel KB Stockham TL Verma M Strong MJ Janicak PG 《Journal of forensic sciences》2001,46(5):1143-1151
In recent years, there has been a notable increase in the number of reports on drug-facilitated sexual assault. Benzodiazepines are the most common so-called "date-rape" drugs, with flunitrazepam (Rohypnol) being one of the most frequently mentioned. The aim of this study was to determine whether flunitrazepam and its major metabolite 7-aminoflunitrazepam could be detected in hair collected from ten healthy volunteers after receiving a single 2 mg dose of Rohypnol using solid phase extraction and NCI-GC-MS. Such data would be of great importance to law enforcement agencies trying to determine the best time interval for hair collection from a victim of drug-facilitated sexual assault in order to reveal drug use. Ten healthy volunteers (eight women and two men, 21 to 49 years old) participated in the study. The following hair samples were collected from each volunteer: one before flunitrazepam administration, and 1, 3, 5, 14, 21, and 28 days after. In five volunteers, 7-aminoflunitrazepam was detected 24 h after flunitrazepam administration and remained in hair throughout the entire 28-day study period (0.6-8.0 pg/mg). In two cases, 7-aminoflunitrazepam appeared in hair 21 days after drug intake (0.5-2.7 pg/mg), and in two subjects 14 days later (0.5-5.4 pg/mg). In one volunteer, 7-aminoflunitrazepam was detected on day 14 and 21 but concentrations were below the quantitation limit. Flunitrazepam was detected in some samples but all concentrations were below the quantitation limit (0.5-2.3 pg/mg). 相似文献
934.
Moretti TR Baumstark AL Defenbaugh DA Keys KM Smerick JB Budowle B 《Journal of forensic sciences》2001,46(3):647-660
The amplification and typing conditions for the 13 core CODIS loci and their forensic applicability were evaluated. These loci are CSF1PO, FGA, TH01, TPOX, vWA, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, and D21S11. Results were obtained using the multiplex STR systems AmpFlSTR Profiler Plus and AmpFlSTR COfiler (Applied Biosystems, Foster City, CA), GenePrint PowerPlex (Promega Corporation, Madison, WI), and subsets of these kits. For detection of fluorescently labeled amplified products, the ABI Prism 310 Genetic Analyzer, the ABI Prism 377 DNA Sequencer, the FMBIO II Fluorescent Imaging Device, and the Fluorlmager were utilized. The following studies were conducted: (a) evaluation of PCR parameter ranges required for adequate performance in multiplex amplification of STR loci, (b) determination of the sensitivity of detection of the systems, (c) characterization of non-allelic PCR products, (d) evaluation of heterozygous peak intensities, (e) determination of the relative level of stutter per locus, (f) determination of stochastic PCR thresholds, (g) analysis of previously typed case samples, environmentally insulted samples, and body fluid samples deposited on various substrates, and (h) detection of components of mixed DNA samples. The data demonstrate that the commercially available multiplex kits can be used to amplify and type STR loci successfully from DNA derived from human biological specimens. There was no evidence of false positive or false negative results and no substantial evidence of preferential amplification within a locus. Although at times general balance among loci labeled with the same fluorophore was not observed, the results obtained were still valid and robust. Suggested criteria are provided for determining whether a sample is derived from a single source or from more than one contributor. These criteria entail the following: (a) the number of peaks at a locus, (b) the relative height of stutter products, and (c) peak height ratios. Stochastic threshold levels and the efficiency of non-templated nucleotide addition should be considered when evaluating the presence of mixtures or low quantity DNA samples. Guidelines, not standards, for interpretation should be developed to interpret STR profiles in cases, because there will be instances in which the standards may not apply. These instances include (a) a primer binding site variant for one allele at a given locus, (b) unusually high stutter product, (c) gene duplication, and (d) translocation. 相似文献
935.
An 18-year-old university student with Osler-Weber-Rendu disease collapsed in the bathroom. Attempted resuscitation was unsuccessful. Her past history included recurrent epistaxes, mucosal telangiectasias, intracranial arteriovenous malformations with previous hemorrhage, a single pulmonary arteriovenous malformation, recent onset of grand mal seizures, and depression. There was a positive paternal family history. At autopsy the pulmonary arteriovenous malformation was confirmed. In addition, within the brain there were widespread areas of gliosis with hemosiderin deposition and small vascular malformations. No other significant abnormalities were detected and toxicological screening revealed only moderately elevated levels of carbemazepine. Death was attributed to epilepsy associated with glial scarring from previous microhemorrhages. The detection of vascular malformations in the lung or brain at autopsy should prompt careful examination of all tissues for similar lesions. Given the possibility of Osler-Weber-Rendu disease in such cases, fibroblast cultures should be undertaken to enable molecular studies to proceed. The heritable nature of this disorder necessitates accuracy of diagnosis at autopsy; once the diagnosis is confirmed family screening should be recommended. 相似文献
936.
Microscopic characteristics of hacking trauma 总被引:1,自引:0,他引:1
Tucker BK Hutchinson DL Gilliland MF Charles TM Daniel HJ Wolfe LD 《Journal of forensic sciences》2001,46(2):234-240
The purpose of this study was to determine if it is possible to associate machetes, axes, and cleavers with the microscopic parallel striations they leave on the cut surfaces of the bone. Hacking trauma was experimentally inflicted on pig bones using machetes, axes, and cleavers. Negative impressions of both the cut surfaces of the bone and the weapon blades were analyzed using scanning electron microscopy. The results of this investigation indicate that it is possible to correlate a class of hacking weapons to trauma inflicted on bone by these weapons. 相似文献
937.
Lewis LA Smithwick RW Devault GL Bolinger B Lewis SA 《Journal of forensic sciences》2001,46(2):241-246
Chemical processes involved in the development of latent fingerprints using the cyanoacrylate fuming method have been studied. Two major types of latent prints have been investigated-clean and oily prints. Scanning electron microscopy (SEM) has been used as a tool for determining the morphology of the polymer developed separately on clean and oily prints after cyanoacrylate fuming. A correlation between the chemical composition of an aged latent fingerprint, prior to development, and the quality of a developed fingerprint has been observed in the morphology. The moisture in the print prior to fuming has been found to be more important than the moisture in the air during fuming for the development of a useful latent print. In addition, the amount of time required to develop a high quality latent print has been found to be within 2 min. The cyanoacrylate polymerization process is extremely rapid. When heat is used to accelerate the fuming process, typically a period of 2 min is required to develop the print. The optimum development time depends upon the concentration of cyanoacrylate vapors within the enclosure. 相似文献
938.
939.
940.