Sensitive and specific quantification of human genomic deoxyribonucleic acid (DNA) in forensic science specimens: casework examples.

We describe the forensic science application of a method for quantification of human genomic deoxyribonucleic acid (DNA). The two cases cited in this report involve DNA samples extracted from skin tissue and bloodstained clothing recovered from different crime scenes. High-molecular-weight DNA was recovered from both specimens, and the concentrations of these DNAs were estimated to be approximately 0.5 microgram/microL by ethidium bromide/agarose gel electrophoresis. Using the human-specific DNA probe p17H8 (locus D17Z1) to quantify the amount of human genomic DNA in these samples, it is shown that less than 1% of the DNA isolated from the skin tissue is of human origin and that the DNA isolated from the bloodstained clothing is effectively devoid of human DNA sequences. These case examples illustrate the need to quantify not only the total amount of DNA recovered from forensic casework material, but also the proportion of the DNA that is of human origin.     

Investigating polyurethane foam as a form of trace evidence.

The aim of this study was to determine whether polyurethane (PU) foam fragments from different sources could be discriminated from each other. Low and high power microscopy was used to determine whether or not foam fragments were distinguishable from each other under various lighting conditions. Once similar foam fragments were declared microscopically indistinguishable, the visible range microspectrophotometer was highly competent in further distinguishing the spectral characteristics in various fragments from each other. Foam fragments from the same source were shown to display no microscopical or chemical variation. Conversely, it was possible to make clear distinctions between foam fragments from different sources.     

Applications of isoelectric focusing in forensic serology

The typing of certain polymorphic proteins present in human body fluids is an important aspect of the analysis of serological evidence. This is particularly true when dealing with evidence related to violent criminal activity such as homocide, assault, or rape. Until recently, the routine analysis of the genetic polymorphisms of interest relied upon conventional electrophoretic techniques such as horizontal starch or agarose slab gel or both, cellulose acetate, and vertical polyacrylamide gradient gel methods. These techniques adequately separate a limited number of common variants. In some cases, these methods are still those of choice. However, as a result of the nature of the conventional approach, problems with time required for analysis, resolution, diffusion of bands, sensitivity of protein detection, and cost are often encountered. Isoelectric focusing (IEF) offers an effective alternative to conventional electrophoresis for genetic marker typing. This method exploits the isoelectric point of allelic products rather than charge-to-mass ratio in a particular pH environment. The advantages of employing IEF include: reduction of time of analysis, increased resolution of protein bands, the possibility of subtyping existing phenotypes, increased sensitivity of detection, the counteraction of diffusion effects, and reduced cost per sample.     

我国土壤污染防治立法研究

我国目前在土壤污染防治方面不仅没有专门性单行法律、法规,而且在《环境保护法》等法律、法规中也只有些零散规定,防治土壤污染的法律基本上是一项空白,缺乏系统的、可操作性的具体法律制度。立法的缺乏直接导致环境管理权的缺乏,这与土壤污染的严峻形势及其防治的实际需要很不相适应,在土壤污染防治问题的原因分析中,几乎都将政策与法律的缺失问题作为最主要原因之一。为了使土壤污染防治有法可依,需要健全和完善土壤污染防治法律、法规体系,目前,最亟需制定的是一部综合性的土壤污染防治的法律,对我国土壤污染防治的目的、基本原则、管理体制和主要制度作出规定。     

公务员精神：现代公共行政的重要基石

公务员精神作为非正式制度,与公务员法共同形成了现代公共行政的基础。文章从分析公务员精神的特点与功用出发,分析了公务员精神的构建有利于树立公务员公正、公平、廉洁和功绩至上的行政理念和价值观,指出了转型时期公务员精神构建的困难,提出了公务员精神构建的路径选择。     

Analysis of N,N-diethyl-m-toluamide (DEET) in human postmortem specimens

N,N-diethyl-m-toluamide (DEET) levels in postmortem specimens of stomach and contents, blood, liver, and urine are reported following ingestion of the compound. DEET was analyzed by gas chromatography with an OV-101 column and a nitrogen phosphorus detector. The presence of the compound in the four postmortem specimens was confirmed by mass spectrometry.     

Group-specific component: a review of the isoelectric focusing methods and auxiliary methods available for the separation of its phenotypes

This review compares the major isoelectric focusing methods that have been published for the separation of group-specific component (Gc) phenotypes since 1978. The various parameters of gel composition, size, electrical and running conditions and sample application points are listed. More current auxiliary methods are also listed. These relate to the extraction of Gc from bloodstains and its identification after isoelectric focusing. Protocols are then recommended for the forensic analysis of Gc phenotypes.