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411.
During the course of conventional testing of CODIS standards at the Alabama Department of Forensic Sciences, a sample with a heterozygous null genotype at D13S317 was discovered using the PowerPlex 1.1 kit (Promega, Madison, WI). The loss of both alleles was confirmed when the sample was amplified using PowerPlex 1.2 primers and resulted in a 9, 10 genotype at this locus. To determine the cause of the silent alleles, the ADFS designed D13S317 primers which encompassed the PowerPlex 1.1 D13S317 primer binding sites and sequenced the region. Both alleles showed the presence of two substitutions (T-->A and G-->T) at positions 1 and 5 (5'-->3') of the reverse primer (positions 196 and 200 of the sequence in GenBank accession number ). Since the mutations were identical on both alleles, they may be assumed to be of ancestral origin.  相似文献   
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A number of prisoners use drugs. Limited information is available about the extent to which urban and urban substance abusers differ in their drug use in criminal justice settings. In addition, many believe that rural areas are protected from drug use. However, findings from this study show only marginally statistical significant differences in drug use between incarcerated rural and urban drug users. It was expected that urban drug users would be more drug career involved with consistently higher levels of drug use and associated problems. Specifically, rural drug users in this study were older at age of first use of marijuana and cocaine; report fewer years of cocaine, hallucinogen, and heroin use; and report more alcohol and sedative use. Findings from this study suggest that rural and urban drug users are similar and that rural areas may be protective from some drug use but risky for other drug use.  相似文献   
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The National Institute of Justice (NIJ) and the National Aeronautics and Space Administration's (NASAs) Goddard Space Flight Center (GSFC) have teamed up to explore the use of NASA developed technologies to help criminal justice agencies and professionals solve crimes. The objective of the program is to produce instruments and communication networks that have application within both NASA's space program and NIJ programs with state and local forensic laboratories. A working group of NASA scientists and law enforcement professionals has been established to develop and implement a feasibility demonstration program. Specifically, the group has focused its efforts on identifying gunpowder and primer residue, blood, and semen at crime scenes. Non-destructive elemental composition identification methods are carried out using portable X-ray fluorescence (XRF) systems. These systems are similar to those being developed for planetary exploration programs. A breadboard model of a portable XRF system has been constructed for these tests using room temperature silicon and cadmium-zinc telluride (CZT) detectors. Preliminary tests have been completed with gunshot residue (GSR), blood-spatter and semen samples. Many of the element composition lines have been identified. Studies to determine the minimum detectable limits needed for the analyses of GSR, blood and semen in the crime scene environment have been initiated and preliminary results obtained. Furthermore, a database made up of the inorganic composition of GSR is being developed. Using data obtained from the open literature of the elemental composition of barium (Ba) and antimony (Sb) in handswipes of GSR, we believe that there may be a unique GSR signature based on the Sb to Ba ratio.  相似文献   
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A new method for automating political-military games as a means of analyzing strategic forces was recently developed and demonstrated by The Rand Corporation. Interest in this technique sprang from dissatisfaction with the dominant methods of analyzing strategic forces: manual political-military games and force exchange models. While each brings important capabilities to the analysis of strategic forces, neither method can independently handle all of the variables required to satisfy the current demands placed on strategic analysis. Rand drew upon the discipline used to develop models and the flexibility inherent in gaming to develop its automated wargame. The method promises significant improvement over the traditional methods of strategic analysis in breadth of input and flexibility of application.  相似文献   
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Gotha Canal is perhaps the most gigantic construction work ever undertaken in Sweden. It is a seaway through Sweden that connects the Baltic Sea with the Atlantic Ocean. It is nowadays considered to be one of the most famous cultural landmarks in Sweden from the time it opened for traffic the canal was in 1832 until 1978 the canal was privately owned. Since then, it has been owned by the state. Such a long time of private ownership of transportation link is remarkable. This paper analyses why the change from private to state ownership finally took place and also looks at the implication of this ownership change for profit maximising behaviour and maintenance of the canal. A discussion of how ownership of a cultural landmark like Gotha Canal can be structured is also provided.  相似文献   
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