The efficiency of reduced volume PCR amplification was studied using the VeriFiler™ Express PCR Amplification Kit. Full (25 μL) and reduced (5 μL) volumes were tested in parallel to identify any differences in template DNA sensitivity and other electropherogram parameters. Both volumes produced full DNA profiles down to 0.08 ng/μL DNA concentration at 26 PCR cycles; however, reduced volume produced higher peak heights due to increased signal intensities. Significant difference (p-value ≤ 0.05) in heterozygote peak height ratios was observed between both volumes, where the reduced volume threshold was lowered to 0.6 to accommodate all data points. However, no significant difference (p-value > 0.05) was identified in the stutter ratios between both volumes. The analytical threshold for reduced volume was also determined to be 150 RFU with the presence of template DNA in PCR amplification. When the optimized reduced volume parameters were tested on DNA extracted from buccal swab samples using Prep-n-Go™ Buffer, good quality DNA profiles were produced. Overall, the reduced volume not only showed better results compared to the full volume, but also enable more samples to be processed with a PCR amplification kit, thus reduced the cost.
U.S. schools are facing a crisis of leadership because many school districts are finding it increasingly difficult to recruit new principals. Whereas teachers represent the group from which the largest number of new principals is likely to be drawn, fewer and fewer of them now seem willing to seek administrative positions. Understanding their perspectives provides an important basis for addressing critical shortages. Using survey data from a large Ohio sample, the present study examined the views of teachers with regard to what are commonly perceived as incentives and disincentives associated with the principalship. It also explored the characteristics of teachers that make them more and less receptive to the idea of seeking leadership positions. Results showed that, in general, teachers view the disincentives associated with the principalship as more potent than the incentives. Variables that were significantly associated with the view that the principalship was “worth it” (i.e., that the incentives outweighed the disincentives) included gender (i.e., maleness), administrative licensure, and the tendency to value the practice whereby school leaders groom teachers for leadership positions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.