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81.
Low explosives such as smokeless powder, black powder, and black powder substitutes have been used in illicit pipe bombings throughout the United States. Some of the newer black powder substitutes are formulated with ascorbic acid, which gradually decomposes as the powder ages, making it difficult if not impossible for the forensic chemist to identify it by traditional bulk techniques. A sensitive method for the identification of residual levels of ascorbic acid in black powder substitutes is presented. Powder samples are extracted with a mixture of acetonitrile and bis(trimethylsilyl)acetamide (BSA), which converts carboxylic acid and alcohol functional groups to trimethylsilyl esters and ethers, respectively. Samples are then analyzed by gas chromatography-mass spectrometry (GC-MS). Results have shown that trace amounts of ascorbic acid can be identified at detection limits that are well below those for traditional bulk techniques. Degradation products for ascorbic acid (hydroxylated carboxylic acids, furanones, and lactones) can also be detected.  相似文献   
82.
Outlined in the paper are outlooks for determining a group affiliation of sperm in traces, left in material evidence, within forensic biological expertise. A technique is suggested to separate the spermatozoids from the vaginal epithelium cells--it has been used up to now in genetics alone. The method involves the available reagents and does not need any extra training. Its elaboration and introduction would resolve one of the most often-encountered issues set by the investigating office.  相似文献   
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84.
This study describes the working of a new system that supervises the execution of the punishment phase in the Province of Buenos Aires, Argentina; namely, the Court of Penal Execution, as well as the risk assessment program. It also reports the results of the violent recidivism baseline risk assessment carried out in candidates for conditional release. The cohort studied was recruited during 18 months in the Judicial Department of La Plata, taking into consideration psychopathological and criminological variables. The Psychopathy Checklist-Revised (PCL-R), the Historical, Clinical, and Risk Management--20 (HCR-20), and the Violence Risk Appraisal Guide (VRAG), among others, were used as measures. During the study period, 65 candidates for conditional release were part of the baseline assessment, and they constitute the population of this study. The measures' mean scores were PCL-R, 20.57; HCR-20, 18.58; VRAG, 12.17.  相似文献   
85.
Suicide by asphyxiation with a plastic bag placed over the head is a method that has been advocated by right-to-die groups. Recently, such groups have proposed the introduction of helium into the plastic bag as a means of hastening death. Helium is readily available at toy stores, where it is sold in tanks for balloon inflation. It produces asphyxiation by the exclusion of oxygen in enclosed spaces. We report 7 fatalities throughout an 18-month period involving plastic bag suffocation in conjunction with helium use. These fatalities coincide with publication of an update to a popular right-to-die text in which this method is described. Although right-to-die literature was absent from all scenes, this method was not previously observed in our jurisdiction, and the deaths likely reflect exposure to this information. Because of analytical difficulties in testing for helium in biologic specimens, death certification rests on scene investigation.  相似文献   
86.
87.
Evaluation of links in heroin seizures   总被引:4,自引:0,他引:4  
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88.
Allele frequencies for eight tetranucleotide short tandem repeat (STR) loci-CSF1PO, TPOX, TH01, F13A01, FESFPS, vWA, F13B, LPL-were obtained from a population sample of 105-122 unrelated individuals born in Transylvania and Banat (Romania).  相似文献   
89.
Forensic archaeologists and criminal investigators employ many different techniques for the location, recovery, and analysis of clandestine graves. Many of these techniques are based upon the premise that a grave is an anomaly and therefore differs physically, biologically, or chemically from its surroundings. The work reviewed in this communication demonstrates how and why field mycology might provide a further tool towards the investigation of scenes of crime concealed in forest ecosystems. The fruiting structures of certain fungi, the ammonia and the postputrefaction fungi, have been recorded repeatedly in association with decomposed mammalian cadavers in disparate regions of the world. The ecology and physiology of these fungi are reviewed briefly with a view to their potential as a forensic tool. This application of mycology is at an interface with forensic archaeology and forensic taphonomy and may provide a means to detect graves and has the potential to estimate postburial interval.  相似文献   
90.
Fractures in bones of the skull base (BSB) are preconditioned by the contact zone of interaction between the two below surfaces, i.e. the trace-forming one (object) and the trace-receiving one (bone). On the basis of their independent research, the authors suggest a set of criteria for the expert evaluation of fractures in BSB for the purpose of specifying the properties of the trauma-causing object, which is made with due regard for the anatomic specific features of the trauma zone.  相似文献   
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