Gel Electrophoresis

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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Stammering Its Cause and Its Cure

Stammering Its Cause and Its Cure

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.

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