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101.
This article uses a transaction costs approach to synthesize micro- and macro-theories of corruption in an analysis of corruption in post-Mao China. Macro-theories of corruption include functional, political-institutional, revised modernization, and cultural approaches. These approaches are integrated through a micro-model developed from the principal-agent model and a rational choice model of crime. The micro-model focuses on: the frequency of corrupt opportunities and the stakes involved, external control such as legal sanctions, and internal control or moral constraints. Within this context, this study reveals that corruption during the post-Mao China period was caused by the surge of such opportunities and the failure of internal and external control.  相似文献   
102.
为了探明醛缩酶在支原体中的定位,根据已发表的鸡毒支原体醛缩酶(fba)基因序列设计特异性的引物,以鸡毒支原体Rlow株基因组为模板,通过Overlap PCR点突变扩增鸡毒支原体醛缩酶fba基因,将fba克隆至pET-28a(+)载体后进行序列测定和分析。结果表明,fba基因全长873bp,编码290个氨基酸。将构建的重组表达质粒pET28a-fba转化至大肠杆菌BL21(DE3),在IPTG诱导下成功获得表达融合蛋白rMGfba,大小约为33ku。纯化蛋白并对蛋白进行酶活性检测,结果显示该酶在体外具有与阳性对照醛缩酶相同的催化功能。用该蛋白免疫小鼠制备多克隆抗体,提取鸡毒支原体膜蛋白,Western-blot分析结果显示FBA多抗可与疏水性膜蛋白特异性结合,说明FBA位于鸡毒支原体膜表面。  相似文献   
103.
Recent research has expanded our understanding of sexual homicide offenders (SHOs). However, little exists beyond case reports for older SHOs. We characterized male SHOs ≥ 55 years, comparing them to typical adult male SHOs who are in their 20s. Analysis of 37 years (1976–2012) of US Supplementary Homicide Reports data provided a large SHO sample (N = 3453). Three case reports provide clinical context for the diverse nature and patterns of older SHOs. Only 32 older male SHOs and no older female SHOs were identified. Murders by older SHOs accounted for only 0.5% of US sexual homicides. Unlike typical SHOs that generally target young adult females, over two‐thirds of older SHO victims were ≥40 years, and one‐third were ≥55 years. Sexual homicides by older SHOs, like sexual homicide in general, decreased over the study period. These crimes, while exceedingly rare, do occur, warranting special consideration.  相似文献   
104.
This paper examines the role of China in the G20 and in East Asia in crafting appropriate responses and policies to the global financial crisis. Did China play an important part in the multilateralisation of the Chiang Mai Initiative, and how did China work with other players in East Asia to ‘inoculate’ East Asia against contagion and fallout from the crisis? The paper evaluates the type of leadership displayed by China and the decisions taken during the crisis. It assesses how the Chinese role in its own region and within global institutions such as the G20 would change in the aftermath of these crises.  相似文献   
105.
将通过PCR技术扩增的牛型布鲁氏菌铁离子转运蛋白(Brucellaferric uptake,BfuA)基因克隆至表达载体pCold TF中,构建重组表达质粒pCold TF-BfuA,转化大肠杆菌BL21(DE3)后,在IPTG诱导下表达出大小约为100ku的融合蛋白His-BfuA。Western-blot分析表明,His-BfuA能与布鲁氏菌阳性牛血清发生特异性反应,表明BfuA具有免疫原性。用His-BfuA作为包被抗原,对35份布鲁氏菌阳性牛血清进行ELISA检测,结果所有被检血清均为阳性反应,表明BfuA为潜在的可用于牛型布鲁氏菌诊断的靶蛋白。此外,对BfuA的亚定位结果表明,BfuA为膜蛋白;对His-BfuA的纤连蛋白结合活性及纤连蛋白溶酶原结合活性的试验结果表明,His-BfuA不具有上述2种活性。上述结果为牛型布鲁氏菌病诊断方法的建立及亚单位疫苗的研制奠定了基础。  相似文献   
106.
This paper reports a new capillary zone electrophoresis method for the simultaneous chiral determination of the enantiomers of N,N-dimethylamphetamine (DMA), methamphetamine (MA), ephedrine (E), pseudoephedrine (PE) and methylephedrine (Me-E). In this study, a number of electophoretic parameters were examined and optimized including the choice of chiral selectors, the use of short-chain tetraalkylammonium cations, the effect of chiral selector concentration, buffer concentration, applied voltage and capillary temperature. Heptakis(2,6-di-O-methyl)-beta-cyclodextrin (DM-beta-CD) and tetrabutylammonium (TBA) being the best chiral selector and buffer cation, respectively, the optimized electrophoretic conditions were found to be: 20 mM DM-beta-CD, 50 mM TBAPO(4) at pH 2.5, applied voltage at 30 kV and temperature at 25 degrees C. Under the optimized conditions, all analytes were well separated with resolution factors between 3.3 and 24.0 achieved. Using phentermine as an internal standard, the intra-day (n=8) precisions for the relative migration times and peak areas of all analytes were below 1.09%, while the inter-day precisions (n=12, 6 days) for the relative migration times and peak areas of all analytes were under 3.77%. This method has been applied to the measurement of the enantiomeric purities of the seized DMA samples. The result of the measurement could provide important clues about the possible synthetic pathways of these samples.  相似文献   
107.
Abstract: An investigation is presented of the explosion of a CNG (compressed natural gas) fuel vessel, called a liner, in an urban bus. The explosion happened at a gas station 10 min after filling was completed. There were no traces of soot and flames at the failed liner, which would be indicative of explosion by ignition of the gas. The filling process of the station was automatically monitored and recorded in a computer. There was no unusual record of the filling system that indicated excess pressure at the time of the accident. There were cracks on the liner that were initiated at the outer surface of the cylindrical shell located at a point 4 cm above the lower dome where cracks did not originate easily as a result of overload. Chemical analysis was performed on a specimen that was cut from the liner, and there was no peculiarity in the mix. Mechanical analysis was performed on the specimens and showed that the hardness was not in the specified range because of inadequate heat treatment of the metal. The hardness of the liner was strictly controlled in the manufacturing process. All the liners that were manufactured at the same period with the failed liner were recalled for examination.  相似文献   
108.
109.
In the case of building collapses and overturned structures, a three‐dimensional (3D) collapse or overturn model is required to reconstruct the accident. As construction sites become increasingly complex and large, 3D laser scanning is sometimes the best tool to accurately document and store the site conditions. This case report presents one case of a structure collapse and one case of an overturned crane reconstructed by a 3D laser scanner. In the case of structural collapse of a prefabricated shoring system, a 3D model reconstructed all the members successfully, a task that is nearly impossible using a scale such as a tape measure. The reconstructed prefabricated shoring system was verified through a structural analysis through comparison with the construction drawings to investigate faults in construction. In the case of the overturned crane, the jib angle and other major dimensions were successfully acquired through 3D laser scanning and used to estimate the working radius. As a result, the propriety of the working radius with the given lifting load was successfully determined.  相似文献   
110.
Race-based remedies often are justified by evidence of prior discrimination. They work when they benefit groups previously disadvantaged. This article examines one such remedy—minority business set-asides—and its application in the award of public procurement and construction contracts by the state of New Jersey. Analyzed are contract awards to minority and non-minority/non-women-owned business enterprises in 1990, as well as in periods before, during, and after the imposition of a state minority set-aside program. Using a conventional decomposition approach, the article reveals significant discriminatory gaps in the success of minority- versus non-minority-owned firms in obtaining contracts from the state of New Jersey. The analysis suggests that minority contracting success rates fell from the pre-set-aside era to the set-aside era and that discriminatory outcomes persisted. The particular remedy chosen—while justified based on evidence of prior discrimination—appears not to have reduced the original discrimination nor did it unambiguously benefit minority businesses.  相似文献   
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