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The goal of this work was to optimize and validate a fast amplification protocol for the multiplex amplification of the STR loci included in AmpFlSTR® Profiler Plus® to expedite human DNA identification. By modifying the cycling conditions and by combining the use of a DNA polymerase optimized for high speed PCR (SpeedSTAR™ HS) and a more efficient thermal cycler instrument (Bio-RAD C1000™), we were able to reduce the amplification process from 4 h to 26 min. No modification to the commercial AmpFlSTR® Profiler Plus® primer mix was required. When compared to the current Royal Canadian Mounted Police (RCMP) amplification protocol, no differences with regards to specificity, sensitivity, heterozygote peak height ratios and overall profile balance were noted. Moreover, complete concordance was obtained with profiles previously generated with the standard amplification protocol and minor alleles in mixture samples were reliably typed. An increase in n − 4 stutter ratios (2.2% on average for all loci) was observed for profiles amplified with the fast protocol compared to the current procedure. Our results document the robustness of this rapid amplification protocol for STR profiling using the AmpFlSTR® Profiler Plus® primer set and demonstrate that comparable data can be obtained in substantially less time. This new approach could provide an alternative option to current multiplex STR typing amplification protocols in order to increase throughput or expedite time-sensitive cases.  相似文献   
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This study examined subjective age (how old one feels) and associated variables in 148 emerging adults, ages 20–30 years. Seventy-six participants had a motor disability (cerebral palsy, spina bifida) and 72 had no motor disability. Participants completed questionnaires and were interviewed. There was no significant difference in subjective age between groups. Consistent with previous research, chronological and subjective ages were significantly negatively related in participants without motor disabilities. Chronological and subjective ages were unrelated in the group with motor disabilities but higher psychosocial maturity was related to an older subjective age. Perceptions of how much parents fostered autonomy did not predict subjective age in either group. In both groups, individuals whose parents treated them as younger reported feeling younger. Number of role transitions did not predict subjective age. The results highlight the importance of exploring motor disabilities as a source of diversity in the subjective ages of young people during the transition to adulthood.
Nancy L. GalambosEmail:
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A 10-year review of records of the King County Medical Examiner's Office found 87 deaths due to necrotizing fasciitis and related necrotizing soft tissue infections. In 64 of these cases there were sufficient details to provide an analysis of the manifestations, microbiology, and source of infection. One half (32) of the cases were due to injection of black tar heroin, the nearly exclusive form of heroin in the Northwest United States. Of those due to black tar injection, 24 were clostridial infections with various species represented, eight of which were Clostridium sordellii. Of the 32 cases not associated with drug injection, streptococcal species predominated, with Streptococcus pyogenes isolated in 14 cases. Only three of 32 cases not associated with injection drug use were clostridial infections. These differences were statistically significant. Staphylococcus aureus was isolated from 14 cases; two were methicillin-resistant strains. Overall, 28 of the 64 cases were polymicrobial infections, 15 due to black tar injection and 13 not associated with drug injection. This study supports the conclusion that necrotizing fasciitis due to black tar heroin injection is predominantly a clostridial disease, and in this way differs significantly from necrotizing fasciitis due to other causes.  相似文献   
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The aim of this study was to show the relationships between the enablers for knowledge creation and human capital (HC); the effect of HC on feedback and feedforward; and the influence of these learning flows on organizational performance. To achieve this, we developed a novel theoretical model of relationships and tested this model empirically. We quantitatively test this model using data from firms in the Spanish biotechnology sector. Results show strong relationships between HC and enablers for knowledge creation (redundancy, trust, and autonomy); HC and learning flows (feedback and feedforward); and learning flows and organizational performance. The originality of this study lies in linking—theoretically, empirically, and through a novel model—independent theories of HC, learning, and knowledge creation.  相似文献   
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Bashing of juvenile justice systems in the United States is commonplace. We wondered if this is justified. As a product of our everyday practice and academic assessment, this article draws attention to salutary developments on several fronts, including reduced confinement, systematic assessment of child risks and needs, including use of structured decision‐making tools, evidence based services, and construction of comprehensive service plans. Our goal is to draw attention to best practices such as these that can lead to further advancements in juvenile justice systems.  相似文献   
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