数字签名的技术与法律分析

数字签名的目的和作用主要是证明合同主体的真实身份、证明合同的保密性和完整性以及证明合同主体对合同的确认。而其证明力的有无及证明力的大小又是以技术作保障的,换言之,安全性是证明力的前提和基础,是法律承认其效力的基石。     

从系统论视角剖析情报分析研判系统

情报分析研判本身自成系统包括元素、结构、环境、功能四大要素。从系统论视角对情报分析研判加以全面剖析,这有助于增进情报研判人员对情报分析研判的透彻性认识,以推动情报分析研判工作的规范化和有序化。     

公众安全感指标体系的构建与评价方法研究——以社会治安秩序为视角

公众安全感是指居民对社会治安状况的主观感受和评价,它反映了公众对犯罪的恐惧程度,也成为衡量和谐社会建设的一个重要指标。建立了我国公众安全感的评价指标体系,包括四个层次和四个系统。并为该指标的理论分析提出了主成分分析和聚类分析相结合的评价方法。     

Comparative analysis of 1-phenyl-2-propanone (P2P), an amphetamine-type stimulant precursor, using stable isotope ratio mass spectrometry: Presented in part as a poster at the 2nd meeting of the Joint European Stable Isotope User Meeting (JESIUM), Giens, France, September 2008

The isotope ratios of amphetamine type stimulants (ATS) depend as well on the precursor as the synthetic pathway. For clandestine production of amphetamine and methamphetamine, 1-phenyl-2-propanone (P2P, benzylmethylketone) is a commonly used precursor.Our aim was to determine the variation of the isotope ratios within precursor samples of one manufacturer and to compare seized samples of unknown sources to these values. δ¹³C_V-PDB, δ²H_V-SMOW and δ¹⁸O_V-SMOW isotope ratios were determined using elemental analysis (EA) and gas chromatography (GC) coupled to an isotope ratio mass spectrometer (IRMS). The comparison of all seized samples to the data of the samples of one manufacturer revealed considerable differences. The results show that IRMS provides a high potential in differentiating between precursors from different manufacturers for the clandestine production of ATS and identifying corresponding sources.     

论国家机关、国有事业单位不能成立单位犯罪——以经济分析法学为视角

将国家机关、国有事业单位作为单位犯罪的主体会导致大大降低相关犯罪的刑罚成本,并不利于对此类犯罪的预防。根据以经济分析法学方法进行的分析,国家机关、国有事业单位均不宜成为单位犯罪的主体。     

Quantitative structure–activity relationship (QSAR) methodology in forensic toxicology: Modeling postmortem redistribution of structurally diverse drugs using multivariate statistics

Postmortem redistribution (PMR) constitutes a multifaceted process, which renders the analytical results of drug concentrations inaccurate to be interpreted by forensic toxicologists. The aim of the present study was to evaluate whether quantitative structure–activity relationship (QSAR) methodology could serve as an effective tool to estimate the ability of drugs to redistribute across tissue barriers during postmortem period on the basis of their molecular, physicochemical and structural properties. In this aspect, multivariate data analysis (MVDA) was applied to a set of 77 structurally diverse drugs. PMR data expressed by the central:peripheral concentration ratio (C:P ratio) was taken from the literature. An adequate and robust QSAR model (R² = 0.65, Q² = 0.56, RMSEE = 0.34) was established for 59 (77%) out of 77 drugs. Although the derived QSAR model presented limited applicability, it provided an informative illustration of the contributing molecular, physicochemical and structural properties in PMR process. Drugs with strong basic properties and enhanced molecular size, flexibility, lipophilicity and number of halogens were found to be susceptible to increased PMR. Due to the high complexity of PMR process, further QSAR studies need to focus on structurally related drugs to develop more specific models, which could serve as alternative tools to evaluate PMR for different chemical classes.     

Extraction of high quality DNA from biological materials and calcified tissues

Calcified tissues, such as bone and tooth, and some other sample types, such as those containing adhesive, present a challenge to standard extraction protocols. We have developed a lysis reagent, BTA™ lysis buffer, which is designed for use with PrepFiler™ Kit reagents. The BTA™ lysis buffer disrupts calcified tissue matrices and achieves effective extraction of DNA from pulverized bone and tooth samples. In addition, the BTA™ lysis buffer mildly but efficiently extracts DNA from challenging substrates like tape, chewing gum, and cigarette butts and, as with bone and tooth, DNA from these lysates is purified using established PrepFiler™ reagent extraction protocols.We successfully extracted DNA from powdered human bone samples, chewed gum and smoked cigarettes using BTA™ lysis buffer. Extraction yields for bone, gum and cigarette samples tested were consistent and reproducible. This extraction method efficiently removed potential PCR inhibitors from all samples tested, and C_T values for the internal PCR control of Quantifiler^® Human DNA Quantification Kit were consistent and within the normal range. The DNA extracted from these samples also provided conclusive profiles that were free of PCR artifacts when amplified using the AmpF?STR^® Identifiler^® PCR Amplification Kit. The protocol is easily adapted for automation.