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171.
Using pooled cross‐sectional data from the 1992 to 2005 March Current Population Survey (CPS), this study examines the relationship between minimum wage increases and the economic well‐being of single mothers. Estimation results show that minimum wage increases were ineffective at reducing poverty among single mothers. Most working single mothers were not affected by minimum wage hikes because they already earned wages above state and federal minimum wages. And less‐educated single mothers who were affected did not see a rise in net income because of negative employment and hours effects. For this low‐skilled population, a 10 percent increase in the minimum wage was associated with an 8.8 percent reduction in employment and an 11.8 percent reduction in annual hours worked. © 2008 by the Association for Public Policy Analysis and Management  相似文献   
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The comparison of consecutively manufactured tools and firearms has provided much, but not all, of the basis for the profession of firearm and toolmark examination. The authors accept the fundamental soundness of this approach but appeal to the experimental community to close two minor gaps in the experimental procedure. We suggest that “blinding” and attention to appropriateness of other experimental conditions that would consolidate the foundations of our profession. We do not suggest that previous work is unsound.  相似文献   
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Despite the volume of time officers spend on traffic enforcement encounters, there was limited research exploring how they used their discretion in such interactions. Issues relating to police decision making patterns in the enforcement of motor vehicle laws were particularly salient in light of the on-going debate over racial profiling. This study examined how officers made decisions (in particular, to stop and to sanction) in the course of traffic enforcement. Using field observations and interviews with officers in a small midwestern agency, the authors described the factors and forces that officers used in making discretionary choices. The findings indicated that leniency in sanctioning was very common and that officers expected citizens to be contrite and acknowledge responsibility for their infractions. Implications for larger and more systematic observational studies are discussed.  相似文献   
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In the wake of the Supreme Court's decision in Aviall—that potentially responsible parties (PRPs) are not permitted to seek contribution from other PRPs under CERCLA unless they have been sued or otherwise settled their CERCLA liability—PRPs and the courts have struggled to identify a remedy for those that voluntarily undertake cleanup of contaminated sites. The Atlantic Research decision resolves a conflict among the circuits and clarifies that PRPs voluntarily incurring cleanup costs pursuant to CERCLA, can maintain an action for cost recovery against other PRPs. The authors discuss the current legal landscape regarding actions for cost recovery as presented in Atlantic Research.  相似文献   
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The study of man     
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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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