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111.
Yoram Z. Haftel 《The Review of International Organizations》2013,8(3):389-414
The design of current regional economic organizations (REOs) is remarkably diverse. Some REOs address numerous economic issues, while others have only limited mandates. Some REOs have an independent bureaucracy and a legalized dispute settlement mechanism (DSM), while others do not. What determines this institutional variation? Thinking about these institutions as devices that generate credible commitment to a rule-based regional cooperation, institutionalists maintain that the intensity of commercial ties determine regional institutionalization and institutional independence. A number of studies question this logic and argue that it is “naïve.” Empirical evidence on the links between commerce, economic scope, and regional institutions is scant, however. Using an original data set that contains detailed information on the economic activities and institutional structure of twenty-eight REOs over three decades, this paper presents one of the first systematic analyses of these relationships. The empirical analysis indicates that the institutionalist wisdom is right after all. It shows that higher levels of regional trade are associated with greater institutionalization and economic scope, but only if implementation of signed agreements is accounted for, and that regional commerce and greater economic scope are associated with more independent bureaucracies and more legalized DSMs. 相似文献
112.
113.
Primary study of vascular endothelial growth factor immunohistochemical staining in the diagnosis of early acute myocardial ischemia 总被引:5,自引:0,他引:5
The expression of vascular endothelial growth factor (VEGF) in the model of rat early acute myocardial ischemia was studied by Strept-Avidin-Biotin-Peroxidase Complex (SABC) immunohistochemical staining. After ligating the anterior descending branch of the left coronary artery, an initial rapid (30min) positive expression of VEGF in myocardial ischemic areas was observed, the intensity of positive expression of VEGF increased with the continuation of myocardial ischemia. After 5h infarction, the strongly positive myocytes of SABC-VEGF staining were predominantly limited to perimyocardial infarction areas. No positive expression of VEGF was found in the control group. These findings suggested that SABC-VEGF method could give a sensitive, specific, simple and objective morphologic evidence to the diagnosis of sudden cardiac death caused by acute early myocardial ischemia. 相似文献
114.
Image matching algorithms for breech face marks and firing pins in a database of spent cartridge cases of firearms 总被引:1,自引:0,他引:1
On the market several systems exist for collecting spent ammunition data for forensic investigation. These databases store images of cartridge cases and the marks on them. Image matching is used to create hit lists that show which marks on a cartridge case are most similar to another cartridge case. The research in this paper is focused on the different methods of feature selection and pattern recognition that can be used for optimizing the results of image matching.The images are acquired by side light images for the breech face marks and by ring light for the firing pin impression. For these images a standard way of digitizing the images used. For the side light images and ring light images this means that the user has to position the cartridge case in the same position according to a protocol. The positioning is important for the sidelight, since the image that is obtained of a striation mark depends heavily on the angle of incidence of the light. In practice, it appears that the user positions the cartridge case with +/-10 degrees accuracy.We tested our algorithms using 49 cartridge cases of 19 different firearms, where the examiner determined that they were shot with the same firearm. For testing, these images were mixed with a database consisting of approximately 4900 images that were available from the Drugfire database of different calibers.In cases where the registration and the light conditions among those matching pairs was good, a simple computation of the standard deviation of the subtracted gray levels, delivered the best-matched images. For images that were rotated and shifted, we have implemented a "brute force" way of registration. The images are translated and rotated until the minimum of the standard deviation of the difference is found. This method did not result in all relevant matches in the top position. This is caused by the effect that shadows and highlights are compared in intensity. Since the angle of incidence of the light will give a different intensity profile, this method is not optimal.For this reason a preprocessing of the images was required. It appeared that the third scale of the "à trous" wavelet transform gives the best results in combination with brute force. Matching the contents of the images is less sensitive to the variation of the lighting.The problem with the brute force method is however that the time for calculation for 49 cartridge cases to compare between them, takes over 1 month of computing time on a Pentium II-computer with 333MHz. For this reason a faster approach is implemented: correlation in log polar coordinates. This gave similar results as the brute force calculation, however it was computed in 24h for a complete database with 4900 images.A fast pre-selection method based on signatures is carried out that is based on the Kanade Lucas Tomasi (KLT) equation. The positions of the points computed with this method are compared. In this way, 11 of the 49 images were in the top position in combination with the third scale of the à trous equation. It depends however on the light conditions and the prominence of the marks if correct matches are found in the top ranked position. All images were retrieved in the top 5% of the database. This method takes only a few minutes for the complete database if, and can be optimized for comparison in seconds if the location of points are stored in files.For further improvement, it is useful to have the refinement in which the user selects the areas that are relevant on the cartridge case for their marks. This is necessary if this cartridge case is damaged and other marks that are not from the firearm appear on it. 相似文献
115.
The allele distribution of the systems DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385 and YCAII were investigated in a sample of 121 unrelated males from Slovenia 相似文献
116.
Endogenous ethanol concentrations in blood were determined by sensitive headspace gas chromatography/mass spectrometry in 1557 residents of the United Arab Emirates. The subjects were from 13 nationalities, of both sexes and of different age groups. There was no significant difference in blood ethanol concentration between nationalities or between sexes within and between nationalities. The data was pooled and the overall median, minimum, maximum, 25% percentile and 75% percentile were 0.04, 0.00, 3.52, 0.01 and 0.09 mg/dl respectively. The values of blood ethanol concentration as reported in this study indicate that they are far too low to have any forensic significance. 相似文献
117.
Peter Z. Schochet 《Journal of policy analysis and management》2021,40(1):128-157
Job Corps is the nation's largest and most comprehensive career technical training and education program for at‐risk youth ages 16 to 24. Using the sample from a large‐scale experiment of the program from the mid‐1990s, this article uses tax data through 2015 (20 years later) to examine long‐term labor market impacts. The study finds some long‐term beneficial effects for the older students, with employment gains of 4 percentage points, 40 percent reductions in disability benefit receipt, and 10 percent increases in tax filing rates in 2015. For these students, program benefits exceeded program costs from the social perspective. This study is the first to establish that a national program for disconnected youth can produce long‐term labor market gains, and can be a positive investment made for society. The results suggest that intensive, comprehensive services that focus on developing both cognitive and noncognitive skills are important for improving labor market prospects for this population. 相似文献
118.
目前,我们的邻国俄罗斯已经建立了较为完备的公共危机管理机制.分析俄罗斯危机事件管理机制的框架和特点并从中得到启示,将有助于我国公共危机管理机制的建立. 相似文献
119.
M. Kobek C.H. Jab?oński J. Kulikowska D. Pie?niak C.Z. Chowaniec Z. G?szczyk-O?arowski 《Forensic Science International Supplement Series》2009,1(1):88-90
The authors describe a rare case of lethal methadone intoxication of a 3-week-old infant. Born of a drug-addicted mother who was undergoing methadone substitution therapy, the newborn presented withdrawal symptoms and was immediately admitted to a paediatric ward where it was treated for 3 weeks, without administration of methadone. The infant died during bottle feeding within 24 h following discharge home.A post-mortem examination was performed as well as histopathological, toxicological and genetic tests were carried out in order to establish the cause and mode of death.The autopsy revealed obstruction of the lower air passages by stomach contents along with classical features of asphyxia. Toxicological tests revealed high concentrations of methadone and its metabolite in blood and urine as well as presence of methadone in stomach contents, and the DNA polymorphism analysis of the (sex-specific) amelogenin locus gave a negative result.On the basis of the results of the post-mortem examination, the laboratory tests and the police investigation, it was concluded that the drug was ingested with the bottle milk, and the possibility of administration of methadone at the hospital or its ingestion with the breast milk was precluded. Though both the cause and mode of death were established, the public prosecutor discontinued proceedings in the case due to inability to find the perpetrator. 相似文献
120.
M. Slaus D. Strinovic V. Petrovecki D. Mayer V. Vyroubal Z. Bedic 《Forensic Science International Supplement Series》2009,1(1):69-71