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Currently, gamma-hydroxybutyric acid (GHB/"liquid ecstasy") is frequently abused as a knockout substance. Its detection and the interpretation of the results present numerous problems which are illustrated by case reports. In this context, hair analysis and the increasing significance of gamma-butyrolactone (GBL) are also discussed.  相似文献   
94.
Abstract: A quantification of T1, T2, and PD in high isotropic resolution was performed on corpses. Isotropic and quantified postmortem magnetic resonance (IQpmMR) enables sophisticated 3D postprocessing, such as reformatting and volume rendering. The body tissues can be characterized by the combination of these three values. The values of T1, T2, and PD were given as coordinates in a T1–T2–PD space where similar tissue voxels formed clusters. Implementing in a volume rendering software enabled color encoding of specific tissues and pathologies in 3D models of the corpse similar to computed tomography, but with distinctively more powerful soft tissue discrimination. From IQpmMR data, any image plane at any contrast weighting may be calculated or 3D color‐encoded volume rendering may be carried out. The introduced approach will enable future computer‐aided diagnosis that, e.g., checks corpses for a hemorrhage distribution based on the knowledge of its T1–T2–PD vector behavior in a high spatial resolution.  相似文献   
95.
With the goal of obtaining additional practically applicable methods for estimating the PMI of skeletal remains, 39 samples of human and 5 samples of domestic animal long bones with known PMI (PMI=1 to approximately 2000 years) were tested with two established methods (UV-fluorescence of a freshly sawn cross-section and the luminol test) and two screening tests (Hexagon-OBTI? test and Combur? test) that were being tried out in this context for the first time. The hypothesis underlying this experiment was the supposition that the PMI-related chemiluminescence of the luminol reaction for bone is based on the presence of persisting hemin from hemoglobin molecules in bone. Our results showed that lack of luminescence and reduced UV-fluorescence were more meaningful results for estimating PMI and excluding forensic relevance than a positive luminol reaction or strong UV-fluorescence, as both of the latter findings revealed the limitations of these methods in this particular context. Particularly for cases showing a positive luminol reaction, the use of additional absolute dating methods may be indicated. Against our expectations, both the Combur? test strips and the Hexagon-OBTI? test, which were both devised to demonstrate blood, delivered negative results for all samples. They are thus not suitable for estimating the PMI of skeletal remains. Future research will be necessary to elucidate whether the negative results obtained for these tests may be due to the poor solubility of potentially present hemoglobin or hemoglobin breakdown products in the Tris buffer used in this experiment.  相似文献   
96.
Forensic three-dimensional/computer aided design (CAD)-supported photogrammetry (FPHG) plays an important role in the field of the documentation of forensic relevant injuries; particularly so when a detailed, 3D reconstruction is necessary. This is demonstrated in the case of a patterned blunt injury to the face of a victim, which injury was subsequently proven by FPHG to have been caused by a blow from the muzzle of a soft air gun.The objects to be evaluated had to be series photographed in order to be evaluated virtually on the computer. These photo series were then analyzed with the RolleiMetric system. This system measures and calculates the spatial location of distinctive points on the objects' surfaces, and creates 3D data models of the objects. In a 3D/CAD program, the "virtual 3D model of the injury" is then compared against the "virtual 3D model of the possible injury-causing instrument".The validation of FPHG, as shown by the 3D match between certain characteristics of the muzzle form and the facial injury, demonstrates how this 3D method can be used for patterned wound documentation and analysis.  相似文献   
97.
Abstract

This paper places recent growth and structural transformation in 11 Sub-Saharan African countries in historical and international perspective. During the early post-independence period, resources were reallocated to manufacturing activities with high productivity growth. Structural change stalled in the mid-1970s. When it resumed in the 1990s, workers mainly relocated to distributive trade services. Productivity levels in these activities were higher than in agriculture, enhancing overall economy performance. But services productivity growth was sluggish and increasingly falling behind the world frontier. These patterns are also observed in Latin America, but not in Asia.  相似文献   
98.
The aim of this study is to empirically analyze the performance of technology transfer offices (TTO) in Germany. Although being one of the largest and innovative economies in the world, there is only scarce evidence about the role and performance of TTO in university–industry technology transfer. While policy makers and university managers are often quite optimistic about the impact of TTO in fostering technology transfer into the region, consulting firms and research institutes report such institutions in Germany as superfluous and counterproductive. Using the number of invention disclosures as a performance measure, we analyze how variance in performance can be explained by different organizational structures and variables of TTO. Controlling for regional endowment and university specific effects, our results reveal that TTO performance is mainly a function of the kind of labor division within the TTO and the research intensity of the university. Knowing the drivers of TTO performance may help policy makers and university managers to reflect their strategies, mitigate weak points and thus foster performance.  相似文献   
99.
The analysis of the constituents of fingerprints has been described numerous times, mainly with the purpose of determining the aging effect on fingerprints or showing the differences between donors or groups of donors. In this paper we describe the use of derivatized amino acids to determine the efficacy of the visualization reagents 1,8-diazafluoren-9-one (DFO) and ninhydrin. At present certain conditions are used for the application of these reagents, as determined by trial-and-error investigations, to the effect on fingerprints. The recovery of amino acids from a porous surface can be used as a measure for the efficacy of a visualization agent.In this paper we describe a method for the determination of the amount of amino acid left after reaction with well known fingerprint visualization reagents. This will allow a more scientific approach to method development for fingermark enhancement techniques. Furthermore, investigations on the influence of the concentration of fingermark amino acids, the order of application of and exposure time to reagents and the influence of age of the amino acids were carried out. These studies have resulted in a broader understanding of the mechanism involved in visualization of fingermarks using DFO and ninhydrin.  相似文献   
100.
This paper considers the relation between Bataille and Mauss in the light of the evidence that whilst the two authors are often linked, the relation between the two was characterized by a lack of reciprocity. It argues that it is not surprising that Mauss never mentions the work of Bataille, as Bataille’s sociology, and his theory of sacrifice, searches for meaning of acts in relation to certain vital needs of human nature – an approach which offends against the implacable rationalism of Mauss, and his belief, in the 1930s, in the triumph of reason and progress.  相似文献   
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