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131.
对一份文件最早制成时间的检验一直以来都是全世界文检界的难题之一。核实可疑文件的制成时间没有统一的方法,目前主要通过对纸张、墨迹、打字机、复印机、打印机、传真机、印刷品,以及笔迹和签名等因素的检验来确定一份文件的制成时间。文件检验人员需要充分利用他们手中的文件的内容及文件周边信息所反映出来的条件和材料,进而得出结论。  相似文献   
132.
导论 在过往的两千多年里,政治哲学家、历史学家、人类学家以及社会学家已经完成了对于私有产权形成问题的解答。最近以来,经济学家也加入了探索这个问题的行列。本文所表达的是我自己对这个问题的看法,但愿读者会认为,此项研究对于理解一个复杂的问题来说,是一个理论上的推进。  相似文献   
133.
Ladies, Gentlemen, Thank you for your notification of the 40th anniversary of the Chinese People's Association for Friendship with Foreign Countries and your recognition of the work we have done together to bring closer the People's Republic of China and France.  相似文献   
134.
On a wintry day a 29-year-old woman was found dead beside her car showing head injuries and signs of hypothermia. Several empty packets of sedative and hypnotic drugs were lying inside the car. Toxicological analysis revealed the presence of flunitrazepam (heart blood of the left and right chamber 0.033 mg/L each), norflunitrazepam (left heart blood 0.029 mg/L, right heart blood 0.027 mg/L), 7-amino-flunitrazepam (left heart blood 0.090 mg/L, right heart blood 0.104 mg/L), diazepam (left heart blood 0.395 mg/L, right heart blood 0.386 mg/L), nordazepam (left heart blood 0.112 mg/L, right heart blood 0.115 mg/L) and temazepam (left heart blood 0.034 mg/L, right heart blood 0.033 mg/L). Neither alcohol nor other drugs were found. It was concluded that benzodiazepine intake led to a disturbance of consciousness. Whether the woman died in this situation due to the icy temperature as a result of hypothermia or whether she died or would have died solely due to benzodiazepine overdosage could not be clarified.  相似文献   
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136.
In a doping control case, a urine sample was tested positive for nandrolon. We were asked by the athlete to perform DNA investigations on the questioned urine sample and compare these to a fresh blood sample taken from the athlete in order to detect or rule out manipulation and/or switching of the samples. The urine sample had been collected nine months prior to the investigation and had been stored at 4 degrees C. In a first approach, nuclear DNA systems were investigated that failed with the exception of the Amelogenin system. Due to the high copy number of mitochondrial DNA molecules and the robustness of the mitochondrial genome, we investigated the HVR I and HVR II regions of mitochondrial DNA and obtained reproducible and clear sequencing results for both the blood and the urine samples. Due to the identical sequences, it could not be excluded that the blood sample and the urine sample were from the same individual or an individual having the same maternal lineage.  相似文献   
137.
Development of a 3D-based automated firearms evidence comparison system   总被引:1,自引:0,他引:1  
Since the early 1990's, the idea of automated systems for the comparison of microscopic firearms evidence has received considerable attention. The main objective of such systems is to enable the analysis of large amounts of evidence, therefore, transforming the comparison of firearms evidence from an evidence verification tool into a crime-fighting tool. Two such systems have been widely used in United States forensic laboratories: namely, the Integrated Ballistics Identification System (IBIS) (1) and DRUGFIRE (2). Both IBIS and DRUGFIRE have in common the fact that their characterization of a specimen is based on a two-dimensional (2D) representation of the specimen's surface. Although these systems have provided satisfactory results in the identification of cartridge cases, their performance in the identification of bullets has not yet met firearms examiner's expectations. This project was motivated by the premise that a better characterizations of the bullet's surface should translate into better performance of automated identification systems. A three-dimensional (3D) characterization of the bullet's surface is proposed as an alternative to a 2D characterization. This paper discusses the development and preliminary results obtained with SciClops, an automated microscopic comparison system based on the use of a 3D characterization of a bullet's surface.  相似文献   
138.
Mitochondrial DNA (mtDNA) analysis of forensic samples typically is performed when the quantity and quality of DNA are insufficient for nuclear DNA analysis or when maternal relatives may be the only reference source. Many of the steps required in the analytical process are both lengthy and labor intensive. Therefore, improvements in the process that reduce labor without compromising the quality of the data are desirable. The current procedure requires purification of the amplicons by centrifugal filtration after PCR and prior to cycle sequencing. Because this method requires several manipulations to perform, alternate cleanup procedures were investigated. These include the use of 1) Qiagen QlAquick PCR Purification columns, 2) Concert Rapid PCR Purification columns, and 3) ExoSAP-IT reagent. When the yield of purified amplicons, quality of the sequence profile, and ease of assay were evaluated, the use of ExoSAP-IT reagent for post-amplification purification was chosen to replace the filtration method.  相似文献   
139.
Gene and genotype frequencies in relation to the D3S1358, vWA, FGA, TH01, TPOX, CSF1PO, D5S818, D13S317, and D7S820 loci were determined in a sample of 290 unrelated individuals (204 Caucasians and 86 mulattoes) living in the city of S?o Paulo, Brazil. The sex test Amelogenin was also performed in all subjects from our sample, revealing the expected sex in all instances. Allele frequency data obtained from the analysis of these samples were in the usual range of other population groups with similar racial background. In the sample of Caucasian individuals, panmictic proportions were ruled out in relation to TPOX and CSF1PO loci, but only in the latter was the overall frequency of heterozygotes significantly less than expected. In the sample of mulattoes, Hardy-Weinberg proportions were rejected in relation to FGA and CSF1PO loci, but in no instance were the overall numbers of heterozygotes different from the corresponding expected ones under panmixia. Taking into account all this and also the number of tests performed, the degree of genetic heterogeneity of Brazilian populations, and the critical level reached by the significant results (1% < alpha<5%), the departures from panmixia here observed can be considered to be negligible in altering significantly biologic relationship odds calculated under the assumption of random matings.  相似文献   
140.
Factor analysis is a statistical technique that can provide an understanding of construct validity. Previous research examining the factor structure of the Juror Bias Scale (JBS) has uncovered problems in the scale's assessment of the constructs of probability of commission (PC) and reasonable doubt (RD). We here reevaluate the scale's constructs to better our understanding of the pretrial biases involved in the juror decision-making process. Importantly, previous findings have been limited to college student samples and trial material that has involved rape evidence. This study examines the construct validity of the JBS in a sample of 617 jury-eligible adults drawn from the community, and the predictive validity of the JBS is examined across 3 distinct trial scenarios. The results parallel earlier findings, indicating that although RD is a tenable and useful construct affecting juror decision-making, PC may be a less relevant pretrial bias. We therefore suggest that future research emphasize alternative constructs, such as confidence and cynicism in the criminal justice system.  相似文献   
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