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941.
Abstract: Synthetic cannabinoid agonists are chemically diverse with multiple analogs gaining popularity as drugs of abuse. We report on the use of thin layer chromatography, gas chromatography mass spectrometry, high‐performance liquid chromatography, and liquid chromatography time of flight mass spectrometry for the identification and quantitation of these pharmacologically active chemicals in street drug dosage forms. Using these approaches, we have identified the synthetic cannabinoids JWH‐018, JWH‐019, JWH‐073, JWH‐081, JWH‐200, JWH‐210, JWH‐250, CP47,497 (C=8) (cannabicyclohexanol), RCS‐4, RCS‐8, AM‐2201, and AM‐694 in various commercially available products. Other noncannabinoid drugs including mitragynine have also been detected. Typical concentrations of drug in the materials are in the range 5–20 mg/g, or 0.5–2% by weight for each compound, although many products contained more than one drug.  相似文献   
942.
Illegal trade in snake parts has increased enormously. In spite of strict protection under wildlife act, a large number of snakes are being killed ruthlessly in India for venom and skin. Here, an interesting case involving confiscation of crystallized dried snake venom and subsequent DNA-based species identification is reported. The analysis using the universal primers for cytochrome b region of the mitochondrial DNA revealed that the venom was extracted from an Indian cobra (Naja naja). On the basis of this report, the forwarding authority booked a case in the court of law against the accused for illegal hunting of an endangered venomous snake and smuggling of snake venom. This approach thus has immense potential for rapid identification of snake species facing endangerment because of illegal trade. This is also the first report of DNA isolation from dried snake venom for species identification.  相似文献   
943.
This study provides evidence of craniofacial growth variation between the sexes in juveniles of European descent. Data were collected from lateral cephalometric radiographs belonging to the Michigan Craniofacial Growth Study. The collection consists of longitudinal lateral radiographs that represent individuals 5-16 years of age. Each radiograph was manually traced on hyprint vellum from which eight craniometric points were identified. From these points, 20 craniofacial measurements were recorded and then analyzed by means of a canonical discriminant function analysis. Sex classification equations were then created by applying a backward stepwise procedure to the discriminant functions. The analysis demonstrates the presence of sexually dimorphic differences in craniofacial growth. The neurocranium is the most sexually dimorphic region of the juvenile craniofacial skeleton, until the onset of puberty. Size is the main source of variation with males having taller and longer heads than females. Overall, sex classification in the sample ranges from 78 to 89% accuracy.  相似文献   
944.
Abstract: Research into witness identification images typically occurs within the laboratory and involves subjective likeness and recognizability judgments. This study analyzed whether actual witness identification images systematically alter the facial shapes of the suspects described. The shape analysis tool, geometric morphometrics, was applied to 46 homologous facial landmarks displayed on 50 witness identification images and their corresponding arrest photographs, using principal component analysis and multivariate regressions. The results indicate that compared with arrest photographs, witness identification images systematically depict suspects with lowered and medially located eyebrows (p = <0.000001). This was found to occur independently of the Police Artist, and did not occur with composites produced under laboratory conditions. There are several possible explanations for this finding, including any, or all, of the following: The suspect was frowning at the time of the incident, the witness had negative feelings toward the suspect, this is an effect of unfamiliar face processing, the suspect displayed fear at the time of their arrest photograph.  相似文献   
945.
Abstract: As a powerful alternative to short tandem repeat (STR) profiling, we have developed a novel panel of 47 single nucleotide polymorphisms (SNPs) for DNA profiling and ABO genotyping. We selected 42 of the 47 SNPs from a panel of 86 markers that were previously validated as universal individual identification markers and identified five additional SNPs including one gender marker and four ABO loci. Match probability of the 42 validated SNPs was found to be 9.5 × 10?18 in Han Chinese. SNP analysis correctly assessed a panel of historical cases, including both paternity identifications in trios and individual identifications. In addition, while STR profiling of degraded DNA provided information for 11 loci of 16 potential markers with low peak intensities, SNPstream® genotyping was sufficient to identify all 47 SNPs. In summary, SNP analysis is equally effective as STR profiling, but appears more suited for individual identification than STR profiling in cases where DNA may be degraded.  相似文献   
946.
A second collaborative exercise on RNA/DNA co-analysis for body fluid identification and STR profiling was organized by the European DNA Profiling Group (EDNAP). Six human blood stains, two blood dilution series (5-0.001 μl blood) and, optionally, bona fide or mock casework samples of human or non-human origin were analyzed by the participating laboratories using a RNA/DNA co-extraction or solely RNA extraction method. Two novel mRNA multiplexes were used for the identification of blood: a highly sensitive duplex (HBA, HBB) and a moderately sensitive pentaplex (ALAS2, CD3G, ANK1, SPTB and PBGD). The laboratories used different chemistries and instrumentation. All of the 18 participating laboratories were able to successfully isolate and detect mRNA in dried blood stains. Thirteen laboratories simultaneously extracted RNA and DNA from individual stains and were able to utilize mRNA profiling to confirm the presence of blood and to obtain autosomal STR profiles from the blood stain donors. The positive identification of blood and good quality DNA profiles were also obtained from old and compromised casework samples. The method proved to be reproducible and sensitive using different analysis strategies. The results of this collaborative exercise involving a RNA/DNA co-extraction strategy support the potential use of an mRNA based system for the identification of blood in forensic casework that is compatible with current DNA analysis methodology.  相似文献   
947.
指纹状态属性的认定是当前指纹鉴定工作的一个新课题。指纹鉴定中的押名指印一般情况下都是押名人生前主动捺印形成的,但在实践中有时会出现作案人为了扰乱侦查视线、逃避惩罚或获取某种利益,而利用尸体指纹捺印伪造死者生前的押名指印的情况,因此对尸体指纹种类认定的研究将有助于侦查破案或对事实的确认。早期尸体现象是尸体指纹具备区别于活体指纹的特定性和相对稳定性的关键,再加上指纹本身所具有的反映性,这"三性"共同构成了尸体指纹种类认定的科学基础,为判定尸体指纹提供了理论依据。对于尸体指纹的研究,一方面须得益于尸体指纹捺印外观特征规律的深入总结,而另一方面也需要将微观层面的尸体指纹汗孔特征作为研究的切入点。总之,研究的最终目的就是提高尸体指纹种类认定的科学可靠性,进而使这一认定结论能作为一种科学的鉴定意见在诉讼中运用。  相似文献   
948.
涉讼司法鉴定收费制度的检视与重构   总被引:1,自引:0,他引:1  
拜荣静 《证据科学》2012,20(3):341-352
我国司法鉴定机构正经历着体制性的变革,司法鉴定事务的逐步立法规范,新的运作方式使现在的鉴定机构已成为市场主体,鉴定人也成为从鉴定费中获取收益的个体。过高的鉴定费用成为公民运用法律保护其合法权益的瓶颈,因而对鉴定费规制问题必须引起足够的重视。我国鉴定费问题突出表现在收费法律依据、收费标准、收费管理以及司法鉴定法律援助几个方面。鉴定费的收取制度应沿此问题的解决路径出发进行建构,其实质是公民诉权的保障和合法权益的维护。  相似文献   
949.
王华朋  杨军  许勇 《证据科学》2012,20(1):109-111
本文把成功应用于DNA检验的证据评估方法(似然比)应用于法庭语音证据评估之中,提取语音的LPC作为识别特征,并使用45人电话对话录音中元音/a/作为样本进行了测试。结果表明该方法不仅能正确识别说话人,而且能根据当前嫌疑人样本和问题语音样本的差异,量化该语音样本作为证据的力度,为法庭提供科学合理的证据评估结果和科学解释。同时,自动特征提取的引入比起人工提取共振峰特征,提高了工作效率,识别系统性能也获得大幅提升。  相似文献   
950.
公正仰仗于完善的司法,目前我国的司法会计鉴定工作存在诸多问题,如鉴定依据不充分、鉴定责任不明确,有时对于同一案件的财务事实,出现多种鉴定结论、甚至是截然相反的鉴定结论,使得法院无从审理。文中就司法会计鉴定工作中存在的问题及如何解决这些问题,进行了分析研究,以期对规范我国司法会计鉴定实践提供参考。  相似文献   
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