Thesis (M.D.)--University of Hong Kong, 2000. / Includes bibliographical references (leaves 164-189).

Thesis (M.S.)--Indiana University, 2007. / Includes bibliographical references (leaves 65-76).

Thesis (Ph.D.)--University of Hong Kong, 1985. / Also available in print.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1973. / Typescript. Vita. Description based on print version record. Includes bibliographical references (leaves 118-120).

Thesis (M. Communication Pathology)--University of Pretoria, 2004. / Includes bibliographical references.

Thesis (M.D.)--University of Hong Kong, 2000. / Includes bibliographical references (leaves 164-189) Also available in print.

Thesis (Ph. D.)--Georgia State University, 2006. / Title from title screen. Mary Beth Walker, committee chair; Laura O. Taylor, M. Melinda Pitts, Sally Wallace, committee members. Electronic text (89 p. : ill. (some col.)) : digital, PDF file. Description based on contents viewed May 21, 2007. Includes bibliographical references (p. 84-88).

Thesis (MVOE)--University of Stellenbosch, 2005. / Bibliography. Also available via the Internet.

Thesis (M.Sc.Eng.) PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / Cavitation is the formation of vapor bubbles in a liquid that is a consequence of tensions acting on the liquid. It is of great interest to lots of different scientific fields such as fluid mechanics, acoustics, hydraulic engineering and biology. Although widely studied in macroscale and microscale confined liquids, heterogeneous cavitation at the nanoscale has only been experimentally observed recently in 2-D nanofluidic channels during an evaporation process, where vapor bubbles form and expand inside the nanochannels instead of menisci receding along the channels. Such evaporation-induced cavitation shows a strong correlation with the nanochannel cross-section non-uniformity and exhibited lots of interesting phenomena, including fast evaporation rate and self-controlled bubble dynamics. In this work, we further investigated this new cavitation phenomenon using a series of specially designed 2-D multi-section nanochannels. Each of these channels includes two or three sections of nanochannel with heights of 25 and/or 35 nm and the same width of 3 μm. A modified sacrificial layer etching method was developed to fabricate these nanochannel devices. Water evaporation processes in these channels were recorded using a high-speed camera mounted on an inverted microscope. We observed that cavitation only occurred in multi-section nanochannels with a “Low to High” channel design. In such nanochannels, when menisci receded to the “Low to High” step, bubbles occurred in the higher channel section and started expansion until they occupied the whole section. We explored the origin of these cavitation phenomena and discovered that that initial bubbles were formed during a snap-off process, where meniscus curvature difference induced reverse liquid flows cause air trapping right at the step. The following bubble expansion is a result of evaporation-induced negative pressure (up to -58 bars) as water inside the nanochannels is in a metastable state. We also analyzed water evaporation rates (bubble growth rates) in these nanochannels in the presence of cavitation. While most evaporation rates can be explained by classic vapor diffusion theories or the kinetic limit of evaporation, water evaporation rates in nanochannels with a Low-High-Low design in the presence of cavitation were as high as 630 μm/s, which is even much higher than the kinetic limit of evaporation and cannot be explained by any current theories. This study further expands our understanding of cavitation and provides new insights and explanations for phase-change phenomena at the nanoscale, including cavitation in plants and quick drying process in nanoporous media. The discovered ultra-high evaporation rates in the Low-High-Low nanochannels also offer a new solution to address thermal management needs for next generation electronic devices. / 2031-01-01

Thesis (MTech (Biomedical Technology))--Cape Peninsula University of Technology, 2010 / Consumption of sucrose with a meal containing oxidised and oxidisable lipids cause an increase in oxidative stress which is referred to as postprandial oxidative stress. The modulating effect on postprandial oxidative stress by an antioxidant-rich beverage, fermented rooibos (Aspalathus linearis) was compared to that of a commercial soft drink (soda). Both study beverages contained sucrose and were consumed with a standardised fat meal. The study consisted of two parts, a pilot study (Phase One) where participants consumed either a standardised fat meal with water (control group n = 5) or a standardised fat meal with a sucrose-containing commercial soda (treatment group n = 8) using a parallel design, and the experimental study (Phase Two) where participants (n = 14) consumed the standardised fat meal with the commercial soda (control group) or the rooibos beverage (treatment group) using a crossover design. Specific analytical techniques and methods for determination of plasma glucose, serum insulin, lipid profile, an inflammatory indicator (high sensitive C-reactive protein), plasma antioxidant capacity, whole blood redox status and plasma lipid oxidation biomarkers were used. Results from the pilot study indicated significantly (P<0.05) higher postprandial levels of glucose in the control group at 4 hr and 6hr postprandially. The inflammatory biomarker and triglyceride levels were significantly (P<0.05) elevated in both groups when compared to their respective baselines. Results also showed the total antioxidant capacity and total glutathione levels in the plasma of both groups to be significantly (P<0.05) lowered when compared to the baseline values. The level of lipid oxidation biomarkers in the plasma was significantly (P<0.05) higher at 2 hr, 4 hr and 6 hr post time intervals for thiobarbituric acid reactive substances and 4 hr post time interval for conjugated dienes in the participants consuming the standardised fat meal with soda when compared to the baseline value, while this was reflected only at 2 hr post time interval for thiobarbituric acid reactive substances, with the conjugated dienes levels being significantly (P<0.05) lowered at 6 hr post time interval in the control group. No differences were shown on inter group level for the pilot study. On inter group level, results from Phase Two showed significant (P<0.05) lower levels of plasma glucose at 6 hr post time interval in the treatment group when compared to the control group, with insulin levels being significantly (P<0.05) higher in the control group at 4 hr post time interval.