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81.
The recent United States Supreme Court decision in Riegel v. Medtronic, Inc. affirmed the doctrine of pre-emption protection only for those medical devices reaching U.S. markets via the PMA (premarketing approval) process and preserved the previous Lohr v. Medtronic decision's lack of preemption protection for those medical devices marketed via the generally more abbreviated 510(k) clearance mechanism. This paper reviews the logic and faults of the Riegel decision and discusses the implications of the Riegel decision for pre-emption protection for other classes of FDA-approved medical products.  相似文献   
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Recent years have witnessed growing research interest in citizen perceptions of the police. This was likely the result of the community policing movement, which sought to strengthen ties between citizens and the police, as well as to concerns about the legitimacy of the police. Most of this research focused on police agencies in the United States, and little research had been conducted on citizen perceptions of the police in Asian countries. This study sought to fill this void through an analysis of citizen perceptions of the police in South Korea. To address these issues, telephone interview survey data gathered from 11,500 randomly selected citizens were obtained in the rapidly industrializing country, South Korea. Several sets of multiple-regression models were estimated to assess the effect of urbanization, demographics, evaluations of police services, and perceived corruption on citizen satisfaction with police. The results suggested that citizens in small to mid-sized cities and large urban cities were less satisfied with police than were residents of rural areas. In addition, age, evaluations of police service, and perceptions of corruption were related to citizen satisfaction. The results were discussed in comparison to previous research in Asia and the United States and other Western countries.  相似文献   
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Several laboratories have reported the occurrence of a split or n − 1 peak at the vWA locus in PowerPlex® 16 and PowerPlex® ES amplification products separated on 4- and 16-capillary electrophoresis instruments. The root cause of this artifact is post-PCR reannealing of the unlabeled, unincorporated vWA primer to the 3′-end of the tetramethylrhodamine (TMR)-labeled strand of the vWA amplicon. This reannealing occurs in the capillary post-electrokinetic injection. The split peak is eliminated by incorporation into the loading cocktail of a sacrificial hybridization sequence (SHS) oligonucleotide that is complementary to the vWA primer. The SHS preferentially anneals to the primer instead of the TMR-labeled strand of the vWA amplicon. In addition, the n − 10/n − 18 artifact that may be seen at the vWA locus was determined to be due to double-stranded amplicon formed post-electrokinetic injection into the capillary. This was also eliminated by adding in two Complementary Oligo Targets (COT1 and COT2) in addition to the SHS oligonucleotide into the loading cocktail. These three oligonucleotides are complementary to the 33 bases at the 5′-end of the unlabeled vWA amplicon strand and the 60 bases at its 3′-end and therefore compete for hybridization to the TMR-labeled amplicon strand. Incorporation of these three oligonucleotides in the Internal Lane Standard 600 (ILS600) eliminate both the split peak and n − 10/n − 18 artifact in PowerPlex® 16 and PowerPlex® ES amplification products without affecting sizing of alleles at the vWA locus or any locus in the PowerPlex® 16, PowerPlex® Y, PowerPlex® ES, AmpFlSTR® Profiler Plus® ID, AmpFlSTR® Cofiler®, and AmpFlSTR® SGM Plus® kits.  相似文献   
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Middle‐class families face a range of challenges, including uneven income growth, imposing child care costs, and affordability gaps for higher education. The ideal policies by which policy makers and public administrators can aid the middle class are far from obvious. Policy solutions are likely to mirror our government and population, meaning that they will be decentralized and varied. Achieving a “growing and thriving middle class” requires understanding the composition of the middle class across the country. Benchmarking and measuring the middle‐class condition at the state and substate levels is critical to crafting and adopting effective policy solutions. This Viewpoint essay highlights the Colorado context to demonstrate the measurement of the middle class and tracking of its lived experiences.  相似文献   
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This study examines whether the incidence of crossburnings rises in areas where white supremacist organizations, such as the Christian Knights of the Ku Klux Klan, have held rallies or demonstrations. Using data from two public interest groups, Klanwatch and North Carolinians Against Racial and Religious Violence, we track crossburnings and white supremacist activities in 100 North Carolina counties annually for the period 1987–1993. Various statistical models, including an event count analysis that allows each county to have its own level or reporting bias, indicate that the base rate at which crossburnings occur rises sharply in counties where a demonstration has taken place. Since none of the suspected crossburners has apparent ties to white supremacist groups, it may be that white supremacist rallies encourage fellow travelers to engage in this form of racial intimidation.  相似文献   
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