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Gates MF 《Newsweek》2006,147(20):66-67
  相似文献   
86.
Ethanol formation in unadulterated postmortem tissues   总被引:2,自引:0,他引:2  
During the investigation of aviation accidents, postmortem samples obtained from fatal accident victims are submitted to the FAA's Civil Aerospace Medical Institute (CAMI) for toxicological analysis. During toxicological evaluations, ethanol analysis is performed on all cases. Many species of bacteria, yeast, and fungi have the ability to produce ethanol and other volatile organic compounds in postmortem specimens. The potential for postmortem ethanol formation complicates the interpretation of ethanol-positive results from accident victims. Therefore, the prevention of ethanol formation at all steps following specimen collection is a priority. Sodium fluoride is the most commonly used preservative for postmortem specimens. Several studies have been published detailing the effectiveness of sodium fluoride for the prevention of ethanol formation in blood and urine specimens; however, our laboratory receives blood or urine in approximately 70% of cases. Thus, we frequently rely on tissue specimens for ethanol analysis. The postmortem tissue specimens received by our laboratory have generally been subjected to severe trauma and may have been exposed to numerous microbial species capable of ethanol production. With this in mind, we designed an experiment utilizing unadulterated tissue specimens obtained from aviation accident victims to determine the effectiveness of sodium fluoride at various storage temperatures for the prevention of microbial ethanol formation. We found that without preservative, specimens stored at 4 degrees C for 96 h showed an increase in ethanol concentration ranging from 22 to 75 mg/hg (average 42 +/- 15 mg/hg). At 25 degrees C, these same specimens showed an increase ranging from 19 to 84 mg/hg (average 45 +/- 22 mg/hg). With the addition of 1.00% sodium fluoride, there was no significant increase in ethanol concentration at either temperature.  相似文献   
87.
Inductively coupled plasma mass spectrometry (ICP-MS) was used to analyze glass evidence from a case in which a person broke a window in each of 15 vehicles in a parking lot in order to gain entry into the vehicles. The results of the analysis by traditional methods, which measure the properties of color, thickness, density, and refractive index, are also reported. A total of 15 known samples representing the windows on the cars and 42 questioned glass fragments recovered from the suspect and the police vehicle where the suspect was sitting were submitted for analysis. Density comparisons separated one of the known samples into three samples, increasing the number of known samples from 15 to 17. The concentrations of 16 elements were measured for all but three of the samples using an external calibration ICP-MS method with internal standardization. Color assessment (non-instrumental) separated the 17 known samples into two groups, and refractive index measurements resulted in six groups when the Emmons double variation method was used and ten groups when the Glass Refractive Index Measurement 2 (GRIM2) system was used. Elemental analysis, by itself, differentiated all of the known samples from each other and associated four of the known sample fragments with several of the questioned sample fragments. The informing power of RI, density, and elemental analysis comparisons is evaluated and a summary of the case results is reported.  相似文献   
88.
This paper discusses trends in criminal justice and penal policy over the past twenty‐five years. This period has been characterised as a time of penal populism, which originated in the failure of the 1991 Criminal Justice Act, and the competition between the main political parties to be ‘tough on crime’. However, this is not the only trend to be found in penal policy. There has continued to be a strong undertow of support for rehabilitation and community penalties, including restorative justice. There has been pressure from the left as much as the right to take domestic violence, sexual offences against women and children, and hate crimes more seriously. There have been pressures to meet performance targets—which gradually transformed into calls to build the legitimacy of the justice system. Finally, there have been pressures to privatise criminal justice agencies. These various impulses have sometimes amplified and sometimes counteracted the pressures towards tough penal policy. If the period of intense penal populism ran from 1993 to 2007, inertia in the system has ensured that there have been no significant attempts to row back from tough policies, and to reassert the values of penal parsimony. Given that money has been tight since 2007 and crime has continued to fall, this must amount to a lost opportunity of significant proportions.  相似文献   
89.
Three commercially available integrated rapid DNA instruments were tested as a part of a rapid DNA maturity assessment in July of 2018. The assessment was conducted with sets of blinded single-source reference samples provided to participants for testing on the individual rapid platforms within their laboratories. The data were returned to the National Institute of Standards and Technology (NIST) for review and analysis. Both FBI-defined automated review (Rapid DNA Analysis) and manual review (Modified Rapid DNA Analysis) of the datasets were conducted to assess the success of genotyping the 20 Combined DNA Index System (CODIS) core STR loci and full profiles generated by the instruments. Genotype results from the multiple platforms, participating laboratories, and STR typing chemistries were combined into a single analysis. The Rapid DNA Analysis resulted in a success rate of 80% for full profiles (85% for the 20 CODIS core loci) with automated analysis. Modified Rapid DNA Analysis resulted in a success rate of 90% for both the CODIS 20 core loci and full profiles (all attempted loci per chemistry). An analysis of the peak height ratios demonstrated that 95% of all heterozygous alleles were above 59% heterozygote balance. For base-pair sizing precision, the precision was below the standard 0.5 bp deviation for both the ANDE 6C System and the RapidHIT 200.  相似文献   
90.
RETHINKING URBAN COMPETITIVENESS, COHESION AND GOVERNANCE
Nick Buck, Ian Gordon, Alan Harding and Ivan Turok (eds)
Palgrave Macmillan, 2005, 317 pp., £19.99 (pb) ISBN: 1403906807  相似文献   
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