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301.
The combination of soil's ubiquity and its intrinsic abiotic and biotic information can contribute greatly to the forensic field. Although there are physical and chemical characterization methods of soil comparison for forensic purposes, these require a level of expertise not always encountered in crime laboratories. We hypothesized that soil microbial community profiling could be used to discriminate between soil types by providing biological fingerprints that confer uniqueness. Three of the six Miami-Dade soil types were randomly selected and sampled. We compared the microbial metagenome profiles generated using amplicon length heterogeneity-polymerase chain reaction analysis of the 16S rRNA genes with inductively coupled plasma optical emission spectroscopy analysis of 13 elements (Al, B, Ca, Cu, Fe, K, Mg, Mn, Na, P, S, Si, and Zn) that are commonly encountered in soils. Bray-Curtis similarity index and analysis of similarity were performed on all data to establish differences within sites, among sites, and across two seasons. These data matrices were used to group samples that shared similar community patterns using nonmetric multidimensional scaling analysis. We concluded that while chemical characterization could provide some differentiation between soils, microbial metagenome profiling was better able to discriminate between the soil types and had a high degree of reproducibility, therefore proving to be a potential tool for forensic soil comparisons. 相似文献
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304.
灌服毒鼠强诱导大鼠细胞DNA的损伤研究 总被引:1,自引:0,他引:1
目的研究毒鼠强体内染毒后,毒鼠强对大鼠脑细胞、心肌细胞、淋巴细胞DNA的损伤作用。方法选择健康Sprague-Dawley大白鼠20只,分成5组,每组4只,采用灌胃方法使大鼠毒鼠强体内染毒,按0.2,0.1,0.05,0.01mg·kg-1制作大鼠毒鼠强中毒模型,并以灌服生理盐水的健康大鼠为对照,分离实验大鼠的淋巴细胞、心肌细胞和脑细胞,用彗星电泳的方法测定不同浓度毒鼠强中毒后的细胞DNA损伤。结果0.2,0.1,0.05,0.01mg·kg-1剂量组的毒鼠强均可引起大鼠的淋巴细胞、心肌细胞和脑细胞DNA损伤,均与对照组差异有显著性(P<0.01)。结论毒鼠强诱导体内细胞DNA损伤可能是毒鼠强毒性作用机制之一。 相似文献
305.
周国平 《江南社会学院学报》2005,7(2):11-15,33
政党制度安全,就是指在特定的政党政治框架中,一国政党制度不存在危险或受到内外执政风险影响下仍能保持政党制度的巩固。在新的国际国内形势下,我国政党制度面临着前所未有的挑战:我国成为国际敌对势力“西化”的主要目标;苏联模式政党制度彻底瓦解,多党制在世界范围内不断扩展;信息传播全球化网络化,思想舆论环境日趋复杂;我国社会阶级阶层结构深刻变化,出现了多样化发展的趋势。面对压力和挑战,我们必须坚持中国共产党领导的多党合作制度不动摇;重新审视和定位中国共产党特别是各民主党派的代表性;提高政治协商制度的体制化水平;推进政治协商具体工作的规范化和制度化;大胆借鉴世界各国政党和政党制度建设的有益成果。 相似文献
306.
Cathleen?FogelEmail author 《International Environmental Agreements: Politics, Law and Economics》2005,5(2):191-210
This paper explores the dynamics of the production of global knowledge by an international knowledge organization, in this case the Intergovernmental Panel on Climate Change. Based on previous notions of international boundary organizations, the idea of international knowledge organizations emphasizes the knowledge generation function of such organizations rather than their convening function. Using the case of controversial Kyoto Protocol biotic carbon sequestration policies, I argue that boundary work and uncertainty management are the essential dynamics in the successful construction of global knowledge by international knowledge organizations. This uncertainty management occurs in a manner broadly, although not completely, in conformance with the institutional preferences of powerful policy actors. Global knowledge can legitimate and help refine global policies, but the process of its construction must be iterative and transparent if it is to be credible for global environmental governance over the long-term. 相似文献
307.
Hashimoto T Howitt DG Land DP Tulleners FA Springer FA Wang S 《Journal of forensic sciences》2007,52(5):1082-1088
The discrimination of noncolored transparent polyethylene bags was studied by several nondestructive and semidestructive analytical methods. X-ray diffraction, infrared spectroscopy, and optical microscopy (differential interference contrast microscopy and phase contrast microscopy) were applied to polyethylene films. X-ray diffraction was used to distinguish variations in the crystalline phase, infrared spectroscopy was used to distinguish variations in the molecular components, and optical microscopy was used to distinguish the different surface morphologies. The results show that X-ray diffraction classifies the crystalline phase of the film depending on whether it is made from low-density polyethylene, linear low-density polyethylene, or high-density polyethylene; that infrared spectroscopy is useful to distinguish the molecular components and it is the most discriminating technique; and that optical microscopy discriminate films easily by their morphological differences. 相似文献
308.
目的研究X染色体STR单倍型DXS7424-DXS101在汉族群体中的法医学特征及其分布特点。方法本实验应用PCR和聚丙烯酰胺凝胶电泳及银染技术对DXS7424和DXS101位点进行基因分型,利用相关统计方法进行数据分析。结果汉族151个男性样本中共检出37种单倍型,频率分布在0.0066~0.1391,GD值为0.9453,DP值达到0.9389,最常见单倍型为16-23。结论DXS7424-DXS101作为单倍型分析在汉族群体中具有较高的个体识别率和非父排除率,在法医学特殊亲权鉴定中具有良好的应用前景。 相似文献
309.
目的比较研究几种图形视觉诱发电位技术对视力推断的价值。方法取正常眼40只,分别测试其图形翻转视觉诱发电位、黑白条栅扫描视觉诱发电位和红黑条栅扫描视觉诱发电位,据此推算实验视力,分别与真实视力进行比较,同时各种方法进行彼此比较。结果黑白条栅扫描视觉诱发电位和红黑条栅扫描视觉诱发电位较之图形翻转视觉诱发电位能更为准确、方便、快捷地反映真实视力水平。结论黑白条栅扫描视觉诱发电位和红黑条栅扫描视觉诱发电位与图形翻转视觉诱发电位一样,可用于眼外伤的法医学鉴定。 相似文献
310.
Nagy M Henke L Henke J Chatthopadhyay PK Völgyi A Zalán A Peterman O Bernasovská J Pamjav H 《Forensic science international》2007,169(1):19-26
Haplotype frequencies for 11 Y-STR markers (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385, DYS437, DYS438 and DYS439) in a Romani population (n=63) from Slovakia, Jats of Haryana (n=84) and Jat Sikhs (n=80) from India were determined. The Slovakian Romani, the Haryana and Sikh populations were endogamous based on their unique haplotype ratio and haplotype diversity values, although the Sikh population appeared to be more diverse. AMOVA revealed non-significant differences between the Romanies and significant differences with non-Romani populations. The Macedonian Romani population differed from all Romani populations examined. Frequent haplotypes observed in Romani populations were sporadic in northwest Indian populations. Thirteen out of 316 populations worldwide were found to share the six most frequent haplotypes of the Slovakian Romanies when the screening conditions were narrowed based on the population size to be over 40, the occurrence of the haplotypes was more than one and the sum frequencies of the most frequent haplotypes was at least 0.02. The most common haplotypes were also observed in other Romani groups. When searching with two Indian (Malbar and Malaysian Indian) most frequent haplotypes under the same conditions matches could be detected in all Romani populations except for the Macedonian Romanies. The search with the Jat Sikhs and Jats of Haryana most frequent haplotypes resulted no matches in Romani populations. 相似文献