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131.
Banknote evidence is often submitted after a suspect has attempted to disguise or remove red dye stain that has been released because of an anti-theft device that activates after banknotes have been unlawfully removed from bank premises. Three chlorinated compounds have been synthesized as forensic chemical standards to indicate bank security dye bleaching as a suspect's intentional method for masking a robbery involving dye pack release on banknotes. A novel, facile synthetic method to provide three chlorinated derivatives of 1-(methylamino)anthraquinone (MAAQ) is presented. The synthetic route involved Ultra Clorox bleach as the chlorine source, iron chloride as the catalyst, and MAAQ as the starting material and resulted in a three-component product mixture. Two mono-chlorinated isomers (2-chloro-1-(methylamino)anthraquinone and 4-chloro-1-(methylamino)anthraquinone) and one di-chlorinated compound (2,4-dichloro-1-(methylamino)anthraquinone) of the MAAQ parent molecule were detected by gas chromatography mass spectrometry (GC-MS), and subsequently isolated by liquid chromatography (LC) with postcolumn fraction collection. Although GC-MS is sensitive enough to detect all of the chlorinated products, it is not definitive enough to identify the structural isomers. Liquid-state nuclear magnetic resonance (NMR) spectroscopy was utilized to elucidate structurally the ortho- and para-mono-chlorinated isomers once enough material was properly isolated. A reaction mechanism involving iron is proposed to explain the presence of chlorinated MAAQ species on stolen banknotes after attempted bleaching.  相似文献   
132.
We have analyzed variation of the mitochondrial DNA (mtDNA) hypervariable segments I and II (HVS-I and HVS-II) in 185 randomly chosen individuals from Korea to provide an expanded and reliable Korean database. Combined sequence comparison of HVS-I and HVS-II led to the identification of 167 different haplotypes characterized by 154 variable sites. One hundred and fifty-one of the haplotypes were individual-specific, 14 were found in two individuals and 2 were found in three individuals. A pairwise comparison of the 185 HVS-I/II sequences found an average of 10.11 +/- 4.63 differences between individuals. The random match probability and gene diversity for the combined hypervariable regions were estimated at 0.66% and 0.9988, respectively. Analyzing the expanded database including three previously reported data sets and the present data using haplogroup-based comparisons and comparison with closely related sequences allowed errors to be detected and eliminated, thus considerably improving data quality. Sample division comparisons based on PhiST genetic distance measures revealed no significant population differentiation in the distribution of mtDNA sequence variations between the present data set and a database in The Scientific Working Group on DNA Analysis Methods (SWGDAM), but did indicate differences from other sets of data. Based on the results of mtDNA profiles, almost all of the mtDNA types studied here could be classified into subsets of haplogroups common in east Asia, and show that the Koreans possess lineages from both the southern and the northern haplogroup complexes of east Asian populations. The new data, combined with other mtDNA sequences, demonstrate how useful comparison with closely related mtDNA sequences can be for improving database quality, as well as providing haplotype information for forensic and population genetic analyses in the Korean population.  相似文献   
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Heemin Kim 《Public Choice》1995,84(1-2):77-90
The problems associated with the concept of the core in spatial voting games such as non-existence and instability are well documented. The structurally stable core, presented by Schofield, attempts to resolve these problems by looking at the subset of the core which is still nonempty after a small change in voter preferences. Although this concept, combined with the adoption of supramajoritarian voting rules and weighted voting games, may very well explain the observed stability in reality, it may not be suitable for certain coalition situations. This article proposes a new solution concept, the strongly stable core. The conditions for the existence and the potential location of the strongly stable core are then explored and compared with those of the structurally stable core.  相似文献   
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Improved detection of forensic evidence by combining narrow band photographic images taken at a range of wavelengths is dependent on the substance of interest having a significantly different spectrum from the underlying substrate. While some natural substances such as blood have distinctive spectral features which are readily distinguished from common colorants, this is not true for visualization agents commonly used in forensic science. We now show that it is possible to select reagents with narrow spectral features that lead to increased visibility using digital cameras and computer image enhancement programs even if their coloration is much less intense to the unaided eye than traditional reagents. The concept is illustrated by visualising latent fingermarks on paper with the zinc complex of Ruhemann's Purple, cyanoacrylate-fumed fingerprints with Eu(tta)(3)(phen), and soil prints with 2,6-bis(benzimidazol-2-yl)-4-[4'-(dimethylamino)phenyl]pyridine [BBIDMAPP]. In each case background correction is performed at one or two wavelengths bracketing the narrow absorption or emission band of these compounds. However, compounds with sharp spectral features would also lead to improved detection using more advanced algorithms such as principal component analysis.  相似文献   
138.
This research is about sexual violence among men in the military in South Korea. The authors investigated the frequencies, causes, and circumstances surrounding sexual violence and looked for characteristic features of sexual violence among men in the military in South Korea. They found a high frequency of physical sexual violence and a high level of repetition of sexual violence. Of perpetrators, 81.7% had themselves been victimized. However, the soldiers tended to minimize sexual violence, preferred not to address the issue if possible, criticized or ignored the victims, and did not trust the reporting procedures in place. The authors found that sexual violence was mobilized as a tool in the military to control hierarchy and to create certain masculinities. Regarding the relevance of masculinity, as a salient feature of militaries in general, they believed it might emerge as a common feature across national and cultural differences.  相似文献   
139.
While there is little empirical evidence to demonstrate which types of environmental management systems (EMSs) are associated with greater environmental improvements, governments worldwide are encouraging facilities to adopt them. This research compares the environmental performance of facilities that adopt ISO 14001–certified EMSs, complete (noncertified) EMSs, and incomplete EMSs across multiple environmental media. The authors analyze these relationships for manufacturing facilities in seven countries using a two‐stage model to control for selection bias. Findings indicate that the adoption of all types of EMSs is related to improved environmental performance in an international setting. However, ISO 14001–certified EMSs are associated with environmental improvements to a broader array of environmental media. These findings offer important implications about which types of EMSs have greater promise as voluntary environmental governance tools.  相似文献   
140.
The purpose of this study was to evaluate the reproducibility of the soft tissue (ST) thicknesses at 31 landmarks using the cone-beam computed tomography (CBCT) images obtained from 20 adult subjects. Four observers carried out ST thickness measurements using Skull Measure software, and the inter- and intra-observer error rates were evaluated. Only five of 31 landmarks showed significant differences in recorded ST thickness between the observers. When excluding inexperienced observers, only one landmark showed a significant difference between the observers. Regarding the intra-observer reproducibility, the ST thickness measurements at three landmarks showed low correlation coefficients. The results of this study indicate that CBCT images can be used to measure ST thickness with high reproducibility. However, some landmarks need to be redefined to reliably measure ST thickness on CBCT images.  相似文献   
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