Application of the hexagon-OBTI test and the RSID blood test for the determination of the post-mortem interval of bone samples

In this serial experiment, five human bones with known post-mortem intervals (PMI) in a soil environment from five different epochs (0.2 to approximately 2000 years) were tested in a blind setup with two established rapid tests for the identification of human blood traces (Hexagon-OBTI test and RSID blood test). Based on previous study results concerning the usability of the Luminol test for the first assessment of the PMI of osseous remains, the question arising was whether those test procedures, which are highly sensitive for the detection of human blood components, could also be used to narrow down the post-mortem interval. Five test series were conducted applying modified standard protocols of the manufactures. The aim was to find out whether with prior reaction steps or a prolonged time of incubation hemoglobin or its metabolites can be dissolved from the bone and positive test results can be achieved dependent on the PMI. Four test series yielded negative results for all bone samples and one test series a uniformly weak positive result. The results indicate that rapid tests based on the detection of blood are not suitable for the determination of the PMI of bone samples despite the modification of the standard protocols. Further thorough research is required to clarify the postmortem degradation of hemoglobin in bones.     

The value of skull-photo superimpositions in identifying corpses found in domestic settings

The identification of decomposed corpses found in domestic settings is frequently problematic because comparative material for methods such as forensic odontostomatology, comparative X-ray analysis, or DNA analysis, is not available. In the case presented here, a photograph from an old, expired passport could be used to successfully identify a "domestic setting" corpse in a skull-photo superimposition. In an additional DNA analysis, 13 STR-loci could be amplified from tissue samples taken from the corpse. DNA comparison with the presumed brother of the deceased yielded a probability of 97.09% for siblingship. Y-STR-analysis was, therefore, performed. The results showed that all of the systems for the presumed brother and the corpse conformed, with the exception of the DYS390 locus, in which allele 21 was found for the corpse and allele 22 for the brother. Despite the rapid development of other identification procedures, skull-photo superimpositions remain an important means of identification. Last not least this is due to the increasing ubiquity of personal photo documents in the age of digital photography. The validity of the results from a DNA analysis in an identification process depends largely on the authenticity of the samples available for comparison and the degree to which the DNA from the corpse is preserved. In the case presented by the authors, positive identification of the corpse solely on the basis of the DNA analysis would not have been possible. Numerous constellations can be imagined for decomposed corpses found in domestic settings for which skull-photo superimpositions may be the only possible option for identifying the corpse.     

Criteria for the classification as a "domestic-setting corpse"--a literature search and review to define the term

In German medical and media circles (daily routine, specialist literature, press, novels), the term "domestic-setting corpse" is frequently used, but the term is only vaguely defined. The authors thus decided to perform an in-depth study of the literature, including historic textbooks and all German- and English-language medicolegal journals, going as far back as their first issues, in an attempt to more clearly define the term. Inclusion criteria used in the search were a post-mortem interval of at least 24 hours prior to discovery and discovery of the corpse in a domestic setting. In the literature, 37 cases that complied with the above-mentioned inclusion criteria were found. These cases frequently described "advanced decomposition", often "unclear cause of death" and "problems in identification". These characteristics can thus be considered as being additional pointers in the definition. However, we suggest that the two general defining characteristics of a "domestic-setting corpse" are a post-mortem interval of more than 24 hours before discovery and the discovery of the corpse in a domestic setting.     

Single cells for forensic DNA analysis--from evidence material to test tube

Abstract: The purpose of this project was to develop a method that, while providing morphological quality control, allows single cells to be obtained from the surfaces of various evidence materials and be made available for DNA analysis in cases where only small amounts of cell material are present or where only mixed traces are found. With the SteREO Lumar.V12 stereomicroscope and UV unit from Zeiss, it was possible to detect and assess single epithelial cells on the surfaces of various objects (e.g., glass, plastic, metal). A digitally operated micromanipulator developed by aura optik was used to lift a single cell from the surface of evidence material and to transfer it to a conventional PCR tube or to an AmpliGrid^® from Advalytix. The actual lifting of the cells was performed with microglobes that acted as carriers. The microglobes were held with microtweezers and were transferred to the DNA analysis receptacles along with the adhering cells. In a next step, the PCR can be carried out in this receptacle without removing the microglobe. Our method allows a single cell to be isolated directly from evidence material and be made available for forensic DNA analysis.     

中国网络治理的社会符号学阐释

网络治理是一项复杂系统的社会工程,符号学因其系统性可为网络治理构建和完善提供学理支撑。网络治理和网络空间作为社会符号具有时空性和社会性,其意义会随着历史的变迁和解释主体的不同而变化,主要受历史条件、网络治理实践和国家利益等语境因素的制约。网络空间命运共同体和网络主权是中国网络治理符号系统的重要组成部分,要不断推动其从价值独特性符号向价值共识性符号的转变,即既保持中国特色,又获得国际社会的普遍共识。此外,结合马克思主义哲学理论,中国网络治理具有时代性、人民性、科学性、实践性和全球性,是马克思主义在网络空间治理领域的中国实践,是历史符号在新时代的全新阐释。