Thesis (Ph. D.)--Virginia Commonwealth University, 2007. / Prepared for: Dept. of Chemistry. Includes bibliographical references. Also available online via the Internet.

Thesis (Ph. D.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 166-180). Also available on the World Wide Web.

Thesis (M.S.)--University of Michigan, 1949.

Thesis (Ph. D.)--University of Chicago, Department of Biochemistry and Molecular Biology, December 1999. / Includes bibliographical references. Also available on the Internet.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1960. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Universiẗat, Diss., 2004--Köln.

Universiẗat, Diss., 2005--Köln.

M.Tech. / Sorghum (Sorghum bicolour (L) Moench) and millets are drought resistant cereals (Kent and Evers, 1994) that can grow in areas with poor soils and inconsistent rainfall (Dendy, 1995) where other crops fail. They serve as staple food for many people in tropical sub- Saharan Africa and Asia (Klopfenstein and Hoseney, 1995). Traditionally, bread is made from wheat, which is a temperate cereal not able to grow well in these tropical regions. Leavened bread is seldom made from anything other than wheat (Alais and Linden, 1991) and this is because of the unique visco-elastic property of wheat flour (Hoseney, 1994). Unfortunately in tropical regions such as South Africa wheat is imported at a premium price. The aim of this study was to produce a wheat-finger millet composite flour which is suitable for bread making. Finger millet grain (FMV6) was milled with a laboratory hammer mill fitted with a 0.8 mm screen. The following wheat-finger millet composite doughs were made using standard bread making methods, 0:100 (Control); 90:10; 80:20; 70:30, respectively. Selected quality attributes of the composite dough and the bread thereof were analysed using standard methods. The formulation with 10% finger millet showed better results than other formulations. One formulation (80:20) was selected for improvement which included mixing ingredients at elevated temperatures (50°C and 93°C) and addition of 0.002% of a lipase enzyme, lipopan F; 0.3% vital wheat gluten and a combination of 0.002% lipopan F and 0.3% gluten. All formulations (including the basic formulation) contained Fungamyl Super MA (enzyme combination which contained fungal a-amylase and a xylanase). As the mixing temperatures were elevated, loaf volume decreased but when the industrial baking enzymes were introduced there was an improvement in peak time, dough stability and loaf volume. Image analysis showed that there was an improvement in crumb structure and bubble size distribution after the application of enzyme lipopan F. The crumb colour was lighter and softer when a combination of enzyme lipopan F and vital wheat gluten was applied. The bread made from formulation 80:20 with addition of a combination of enzyme lipopan F and vital wheat gluten (WFM2GL) was more acceptable than other formulations except the control bread. The bread had a high score in taste, crust appearance and mouth feel. The results suggest that there is a potential for producing a composite bread by substituting wheat flour with finger millet flour (up to 20%); mixing at 25°C with application of a combination of a lipase and vital wheat gluten. However, more work is needed to improve the quality of the bread to a greater extent.

Genetic competence is a developmental process in bacteria that allows natural transformation. Competent Gram positive bacteria such as Bacillus subtilis carry a cytosolic helicase which is required for efficient transformation. In this work ComFA is confirmed as a DEAD-box helicase. I also describe a new accessory motif in ComFA that contributes to transformation independently of the helicase activity in ComFA. The newly discovered metal-binding motif consists of four cysteines which are required for transformation and zinc binding. While the zinc finger is required for full function, it is not required for DNA binding. As DEAD-box family helicases are generally non-processive, it appears that at least part of the rapid DNA uptake process is mediated by a non-processive helicase. Active uptake using the ComFA helicase motor may be required to maintain the integrity of the incoming DNA to allow subsequent recombination.

Dexterous manipulation operations using robotic or prosthetic fingers is seemingly facilitated with enhanced tactile feedback. Using a combination of artificial sensors and actuators, a tactile feedback system that conveys tactual information (force, pressure, & temperature) from an artificial fingertip to the user’s hand is developed and tested with subjects. Results reveal that subjects are capable of distinguishing specific actuators with a high degree of accuracy. The sensor density and actuator fidelity of the feedback system is insufficient to yield performance equal to that of a human’s natural tactile senses. Future studies are recommended to identify optimal tactile feedback sites as well as to discover a more robust system to be used in robotic and immersive virtual reality contexts.