Gels must be poured, samples loaded, and electrophoresis conducted prior to scanning the samples. Gel sizes are typically 17 cm X 43 cm X 0.4 cm ('long gel') or 17cm X 32cm X 0.4cm ('short gel'). The denaturing polyacrylamide gel composition for PowerPlex 1.1 analysis is typically 4% polyacrylamide: bis (19:1), 7M urea, and 0.5X Tris-Borate-EDTA buffer (Micka et al. 1999). Alternatively, a 5% Long Ranger™ (FMC BioProducts, Rockland, ME) gel may be used with 7M urea and 1X TBE (Lins et al. 1998). Precast gels, such as the 4.5% R3™ Precast Gels, are also available from Hitachi Genetic Systems (Micka 1999). Gels can be re-used up to four times with similar performance if proper care is taken (Tereba et al. 1998).
The gels are usually run on a SA43 vertical electrophoresis apparatus. A pre-run at 60 W for 30-45 minutes is performed prior to loading the samples in order to warm the gel up to a plate temperature of 45°C to 50°C. The PCR-amplified STR alleles are then loaded onto the gel and separated for 60-90 minutes to resolve the DNA bands. A separation voltage of 60V/cm is often used in order to resolve PowerPlex® 1.1 STR alleles (Schumm et al. 1997).
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This book discusses the futility of curing stammering by common means. It traces various attempts at curing stammering in the past and how wasteful these attempt were, until he discovered a simple program to cure it. The book presents the life of Benjamin Nathaniel Bogue and his struggles with the handicap. Bogue devotes a great deal of text to explain the handicap of stammering, its effects on the body and psychology of the sufferer, and its cure.