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121.
In an age of global combat against terrorism, the recognition and identification of people on document images is of increasing significance. Experiments and calculations have shown that the camera-to-subject distance - not the focal length of the lens - can have a significant effect on facial proportions. Modern passport pictures should be able to function as a reference image for automatic and manual picture comparisons. This requires a defined subject distance. It is completely unclear which subject distance, in the taking of passport photographs, is ideal for the recognition of the actual person. We show here that the camera-to-subject distance that is perceived as ideal is dependent on the face being photographed, even if the distance of 2m was most frequently preferred. So far the problem of the ideal camera-to-subject distance for faces has only been approached through technical calculations. We have, for the first time, answered this question experimentally with a double-blind experiment. Even if there is apparently no ideal camera-to-subject distance valid for every face, 2m can be proposed as ideal for the taking of passport pictures. The first step would actually be the determination of a camera-to-subject distance for the taking of passport pictures within the standards. From an anthropological point of view it would be interesting to find out which facial features allow the preference of a shorter camera-to-subject distance and which allow the preference of a longer camera-to-subject distance.  相似文献   
122.
Abstract

The multidimensional complexities associated with the criminal justice response to human trafficking are well documented. The transient and subversive nature of human trafficking as organised crime and the large number of multidisciplinary role-players involved in coordinating cross jurisdictional efforts to prevent, investigate and prosecute such cases, contribute to this complex undertaking. Complex systems theory suggests that a complex social problem such as human trafficking cannot be approached by using a linear or simplified lens, and requires a holistic perspective on the complex interactions between actors, and emergent behaviour in both the criminal justice system and the human trafficking system that it seeks to combat. This paper explores the characteristics of complexity, and uses illustrations from the lived experiences of actors in South Africa’s efforts to combat human trafficking, in order to demonstrate how complex systems theory could be considered and integrated into the criminal justice response to human trafficking.  相似文献   
123.
The authors report on a case of a dicygotic female twin pair, one of them containing a T/C heteroplasmy in two (heart and brain) of five analysed organs at position nt204 of the HV2 region. Results and especially the evidence of an unequal distribution of the heteroplasmy are discussed.  相似文献   
124.
When a knife is stabbed in bone, it leaves an impression in the bone. The characteristics (shape, size, etc.) may indicate the type of tool used to produce the patterned injury in bone. Until now it has been impossible in forensic sciences to document such damage precisely and non-destructively. Micro-computed tomography (Micro-CT) offers an opportunity to analyze patterned injuries of tool marks made in bone. Using high-resolution Micro-CT and computer software, detailed analysis of three-dimensional (3D) architecture has recently become feasible and allows microstructural 3D bone information to be collected. With adequate viewing software, data from 2D slice of an arbitrary plane can be extracted from 3D datasets. Using such software as a "digital virtual knife," the examiner can interactively section and analyze the 3D sample. Analysis of the bone injury revealed that Micro-CT provides an opportunity to correlate a bone injury to an injury-causing instrument. Even broken knife tips can be graphically and non-destructively assigned to a suspect weapon.  相似文献   
125.
Photography process reduces a three-dimensional (3D) wound to a two-dimensional level. If there is a need for a high-resolution 3D dataset of an object, it needs to be three-dimensionally scanned. No-contact optical 3D digitizing surface scanners can be used as a powerful tool for wound and injury-causing instrument analysis in trauma cases. The 3D skin wound and a bone injury documentation using the optical scanner Advanced TOpometric Sensor (ATOS II, GOM International, Switzerland) will be demonstrated using two illustrative cases. Using this 3D optical digitizing method the wounds (the virtual 3D computer model of the skin and the bone injuries) and the virtual 3D model of the injury-causing tool are graphically documented in 3D in real-life size and shape and can be rotated in the CAD program on the computer screen. In addition, the virtual 3D models of the bone injuries and tool can now be compared in a 3D CAD program against one another in virtual space, to see if there are matching areas. Further steps in forensic medicine will be a full 3D surface documentation of the human body and all the forensic relevant injuries using optical 3D scanners.  相似文献   
126.
The article describes critical investigations concerning the threshold value between endogenous and exogenous concentrations of gamma-hydroxybutyric acid (GHB/"liquid ecstasy") in human blood. The values of GHB in the blood samples of 50 blood donors and 50 postmortem cases were measured with a validated gas-chromatographic/mass-spectrometric procedure according to the guidelines of the GTFCh (Society of Toxicological and Forensic Chemistry). GHB-concentrations were found to range between 0.11 and 1.56 mg/L (mean value 0.54 mg/L/standard deviation 0.37 mg/L/coefficient of variation 68.4 %) in the donors' blood, and between 2.2 and 116 mg/L (mean value 32.4 mg/L/standard deviation 25.6 mg/L/coefficient of variation 79 %) in the postmortem samples, respectively.  相似文献   
127.
Sommaire: Après avoir montré que le chevauchement des programmes fédéraux et provinciaux est une caractéristique fondamentale de l'activité gouvernementale au Canada et qu'il a son origine dans les dispositions de la Constitution, cette étude présente une évaluation qualitative de ses conséquences quant à l'efficience et à l'efficacité du système politico-administratif canadien. Ces conséquences sont envisagées sous l'angle du coût de l'action gouvernementale, de l'efficacité des politiques publiques, du fardeau imposé aux administrés en matière de transactions avec l'État et de la portée du principe de la responsabilité politique des gouvernants envers la population. Vue dans cette perspective, la duplication des activités fédérales et provinciales apparaît comme une source d'inefficience et d'inefficacité pour la gestion des affaires publiques. Elle justifie qu'on s'interroge sérieusement sur la valeur du partage actuel des pouvoirs entre les deux ordres de gouvernement. Abstract: After showing that the overlap between federal and provincial programs is a basic characteristic of government activity in Canada rooted in the provisions of the constitution, this study presents a qualitative assessment of its consequences for the efficiency and effectiveness of the Canadian political-administrative system. These consequences are viewed from the viewpoint of the cost of government action, of the effectiveness of public policy, of the burden the administered face in dealing with governments, and of the scope of governmental political accountability to the people. From this angle, the duplication of federal and provincial activities appears to be a source of inefficiency and ineffectiveness in the management of public affairs. It raises serious questions as to the adequacy of the present sharing of powers between the two levels of government.  相似文献   
128.
Glass surfaces were modified with a combination of dyes and reagents to allow for the potential simultaneous recording of a detailed fingerprint and the detection of the explosive urea nitrate (UN), as a proof of principle of surface modification for simultaneous linking of identity to manipulation of explosives. By coating microscope slides with 9,10‐diphenylanthracene (DPA), p‐dimethylaminobenzaldehyde (p‐DMAB) and p‐dimethylaminocinnamaldehyde (p‐DMAC), a colorimetric change was observed in the presence of UN, while revealing a fingerprint with enough resolution to isolate at least 10 minutiae. This is the first step in creating point‐of‐care devices capable of detecting low concentrations of explosives and drug metabolites and connecting them to a fingerprint.  相似文献   
129.
Indian snakeroot (Rauvolfia serpentina) is a valuable forest product, root extracts of which are used as an antihypertensive drug. Increasing demand led to overharvesting in the wild. Control of international trade is hampered by the inability to identify root samples to the species level. We therefore evaluated the potential of molecular identification by searching for species‐specific DNA polymorphisms. We found two species‐specific indels in the rps16 intron region for R. serpentina. Our DNA barcoding method was tested for its specificity, reproducibility, sensitivity and stability. We included samples of various tissues and ages, which had been treated differently for preservation. DNA extractions were tested in a range of amplification settings and dilutions. Species‐specific rps16 intron sequences were obtained from 79 herbarium accessions and one confiscated root, encompassing 39 different species. Our results demonstrate that molecular analysis provides new perspectives for forensic identification of Indian snakeroot.  相似文献   
130.
Slimming cactus (Hoodia), found only in southwestern Africa, is a well‐known herbal product for losing weight. Consequently, Hoodia extracts are sought‐after worldwide despite a CITES Appendix II status. The failure to eradicate illegal trade is due to problems with detecting and identifying Hoodia using morphological and chemical characters. Our aim was to evaluate the potential of molecular identification of Hoodia based on DNA barcoding. Screening of nrITS1 and psbAtrnH DNA sequences from 26 accessions of Ceropegieae resulted in successful identification, while conventional chemical profiling using DLI‐MS led to inaccurate detection and identification of Hoodia. The presence of Hoodia in herbal products was also successfully established using DNA sequences. A validation procedure of our DNA barcoding protocol demonstrated its robustness to changes in PCR conditions. We conclude that DNA barcoding is an effective tool for Hoodia detection and identification which can contribute to preventing illegal trade.  相似文献   
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