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921.
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924.
The recent formation of a United Kingdom and Irish working group, the Body Fluids Forum (BFF), highlighted the need to investigate different working practices prior to any inter-laboratory comparison work and identification of best practice. Various dilutions of semen were seeded onto swabs and cloth samples for each BFF member laboratory to test using their standard techniques. The results showed that the detection of acid phosphatase on swabs is best achieved using direct testing rather than on an extract from the swab. Extraction methods for spermatozoa require a balance to be achieved between using a sufficient volume of water to ensure optimal release and minimal volume to ensure a concentrated extract. PSA tests were investigated and found to be more sensitive than Choline. DNA profiles were obtained from samples in which no spermatozoa had been detected during microscopic examination.  相似文献   
925.
Statement of Purpose: A decline in state-sponsored terrorism has caused many terrorist organizations to resort to criminal activity as an alternative means of support. This study examines terrorists' involvement in a variety of crimes ranging from motor vehicle violations, immigration fraud, and manufacturing illegal firearms to counterfeiting, armed bank robbery, and smuggling weapons of mass destruction. Special attention is given to transnational organized crime. Crimes are analyzed through the routine activity perspective and social learning theory. These theories draw our attention to the opportunities to commit crime and the criminal skills necessary to turn opportunity into criminality. Through these lenses, the research appraises the “successes” and “failures” of terrorists' engagement in crime. Because “failures” can result from law enforcement efforts to (1) interrupt criminal skill development, and/or (2) remove criminal opportunities via technologies and transportation systems, the research represents a best practices approach to the study and control of terrorism. This project was supported by Grant No. 2003-DT-CX-0002 awarded by the National Institute of Justice, Office of Justice Programs, U.S. Department of Justice. Points of view in this document are those of the author and do not necessarily represent the official position or policies of the U.S. Department of Justice.  相似文献   
926.
A case of fatal poisoning due to the combined effect of alcohol and gasoline following an automobile accident is described. Toxicological analyses by means of gas chromatography and gas chromatography-mass spectrometry permitted the identification and quantitation of alcohol and several hydrocarbons in the heart blood and in the gas in the lung. Great variation was found in the estimates of blood gasoline concentration, depending on which of six constituents of gasoline was chosen for quantitation. The cause of this variation is discussed, together with the possible mechanisms leading to death.  相似文献   
927.
928.
The limited literature on the topic speculates that the rate of ADHD would be higher among incarcerated youth than found in the general population. However, to our knowledge no such published figures exist for juveniles in the United States. This study investigates the likelihood of ADHD diagnosis among 453 incarcerated youth and compares and contrasts a variety of demographic, social, educational, psychological, and criminal characteristics to the general literature on ADHD. Both similarities and differences are reported. This project was supported by Grant #99-RT-VX-K020 awarded by the National Institute of Justice. Points of view in this document are those of the author and do not necessarily represent the official position or policies of the U.S. Department of Justice. An early version of the paper was presented at the annual meeting of the Academy of Criminal Justice Science in Chicago, Illinois.  相似文献   
929.
Microscopical study on estimation of time since death in skeletal remains   总被引:1,自引:0,他引:1  
For the purpose of estimating time since death in skeletal remains, postmortem changes in human compact bones were examined by microradiography and electron microscopy. The UV-fluorescence of the peripheral zone of compact bone was also examined by microscopic spectrophotometry. Microradiographic examination revealed no morphological changes in bones left in the open air for long periods, except one of 15 years since death. In bones left in the soil, vacuoles of 5-10 microns diameter, which contained a honeycomb-like structure formed by small vacuoles of 0.5-1 microns diameter, were found in the peripheral zone of the substantia compacta approximately 5 years since death, and in bones of 6 years or more, this change extended to the mid-zone. In bones left in the sea for 4-5 years, vacuoles of 5-10 microns diameter were observed in the outer peripheral zone of the substantia compacta. The relative intensity of UV-fluorescence in bones dwindled with time since death and the correlation coefficient was considerably high.  相似文献   
930.
Several forms of expert forensic science evaluations exist that rely at least in part on the subjective opinion of the examiner. Human hair identification is one such examination. This paper considers possible sources of influence or bias that may be responsible for examiner errors. Data are reported of an experiment that compares the conventional examination procedure (known versus questioned samples) against an alternative procedure (a lineup of samples) designed to limit the influence of factors that contribute to error. The altenative procedure produced fewer incorrect conclusions (3.8%) than the conventional procedure (30.4%).  相似文献   
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