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Micromachining is the next generation of precision material removal at the micro scale level due to the increase in miniaturization of commercial products. The applications of this technology extend anywhere from electronics to micro scale medical implants. Micromilling has the potential to be the most cost effective and efficient material removal process due to ease of use and accessibility of the tools. This research analyzes vibration of a high speed spindle and then studies micromilling of aluminum and titanium. Finite element analysis and tool modeling compliment experimental data. Cumulative tool wear based on Taylor model shows decreasing tool life with increasing feed rate and increasing cutting speed on aluminum. Inconsistent results are seen when micromilling titanium due to premature chipping of tool noses. A significant nose wear plastically deforms a micromilled subsurface and is verified with microstructure study and microhardness measurements.

Parenteral nutrition (PN) is an essential life sustaining therapy for premature and critically ill infants. However, prolonged PN therapy can lead to life-threatening liver damage, and cause parenteral nutrition associated cholestasis (PNAC). There has been some recent evidence that aluminum accumulation in the livers of PN-fed subjects may lead to hepatic damage leading to liver injury. This dissertation aimed to investigate the role of aluminum as a toxic component of parenteral nutrition and as a risk factor in developing PNAC. The project composed of two main studies. The objectives of the first study were: 1) Evaluate the early morphological changes in piglet liver after intravenous administration of aluminum chloride hexahydrate at a dose of 1500 µg/kg/d.; 2) Determine whether the morphological changes deteriorate further with increasing duration of exposure and whether these changes correlate with changes in biochemical markers of cholestasis; 3) Identify the appropriate imaging technique for studying the ultrastructural changes in the liver; 4) Determine if intravenous injection of high dose aluminum into neonatal piglets disrupts iron homeostasis in the liver. The results showed that intravenous infusion of aluminum in neonatal piglets led to marked elevation in serum total bile acids, and transmission electron microscopy-energy dispersive microanalysis (TEM-EDX) was suitable in detecting the site of Al deposition in the liver and in demonstrating histopathological changes associated with Al infusion. The objectives of the second part were to: 1) Investigate the role of aluminum as a toxic component of parenteral nutrition and as a risk factor in causing liver injury; 2) Evaluate the effect of reducing aluminum content of parenteral nutrition on liver iron homeostasis; 3) Investigate the effect of low aluminum PN and high aluminum PN (regular PN) on the mRNA expression of Bsep and Mrp2. The results showed that administration of PN solution with lower Al content led to reduced levels of serum and hepatic Al in low Al PN group compared to regular PN group. This reduction was associated with less histopathological changes in the liver. On the other hand, administration of regular PN in piglets led to decreased expression of transporter Mrp2. This work suggests that reducing Al content in PN may reduce the development and severity of liver injury in the piglets.

Parenteral nutrition (PN) is an essential life sustaining therapy for premature and critically ill infants. However, prolonged PN therapy can lead to life-threatening liver damage, and cause parenteral nutrition associated cholestasis (PNAC). There has been some recent evidence that aluminum accumulation in the livers of PN-fed subjects may lead to hepatic damage leading to liver injury. This dissertation aimed to investigate the role of aluminum as a toxic component of parenteral nutrition and as a risk factor in developing PNAC. The project composed of two main studies. The objectives of the first study were: 1) Evaluate the early morphological changes in piglet liver after intravenous administration of aluminum chloride hexahydrate at a dose of 1500 µg/kg/d.; 2) Determine whether the morphological changes deteriorate further with increasing duration of exposure and whether these changes correlate with changes in biochemical markers of cholestasis; 3) Identify the appropriate imaging technique for studying the ultrastructural changes in the liver; 4) Determine if intravenous injection of high dose aluminum into neonatal piglets disrupts iron homeostasis in the liver. The results showed that intravenous infusion of aluminum in neonatal piglets led to marked elevation in serum total bile acids, and transmission electron microscopy-energy dispersive microanalysis (TEM-EDX) was suitable in detecting the site of Al deposition in the liver and in demonstrating histopathological changes associated with Al infusion. The objectives of the second part were to: 1) Investigate the role of aluminum as a toxic component of parenteral nutrition and as a risk factor in causing liver injury; 2) Evaluate the effect of reducing aluminum content of parenteral nutrition on liver iron homeostasis; 3) Investigate the effect of low aluminum PN and high aluminum PN (regular PN) on the mRNA expression of Bsep and Mrp2. The results showed that administration of PN solution with lower Al content led to reduced levels of serum and hepatic Al in low Al PN group compared to regular PN group. This reduction was associated with less histopathological changes in the liver. On the other hand, administration of regular PN in piglets led to decreased expression of transporter Mrp2. This work suggests that reducing Al content in PN may reduce the development and severity of liver injury in the piglets.

Class III peroxidases have been identified as secreted proteins involved in plant defense, auxin metabolism, cell wall modification, and regulation of reactive oxygen species. Transcriptome analysis of Arabidopsis has identified many class III peroxidases that respond to aluminum stress. The large number and versatile function of peroxidases make functional characterization of individual peroxidases a challenging task. However, the use of promoter::GUS reporter fusions can help to elucidate the expression pattern of individual peroxidases. To investigate the expression of PER22 and PER73 under aluminum stress in Arabidopsis, single-copy, homozygous, transgenic plants harbouring promoter::GUS reporter fusions were generated through self-pollination and southern blot analyses. Histochemical GUS staining of transgenic lines revealed trichome-specific and vascular-specific expression patterns for PER22 and PER73, respectively. The temporal and spatial expression of PER22 and PER73 suggest that they might be involved in pathogen defense and/or lignification. Further experiments will help define these peroxidase functions under aluminum stress. / Plant Biology

Typescript. / Thesis (Ph. D.)--University of Hawaii, 1961. / Bibliography: leaves [82]-87. / vii, 87 leaves mounted ill., fold. map, diagrs., tables

Thesis (PhD)--University of South Australia, 1997

Thesis (Ph. D.)--University of Washington, 1988. / Vita. Includes bibliographical references.

Thesis (Ph. D.)--Virginia Commonwealth University, 2006. / Prepared for: Dept. of Chemistry. Bibliography: leaves 142-146. Also available online via the Internet.

Thesis (Ph.D.)--McMaster University, 2003. / Advisor: D. S. Wilkinson. Includes bibliographical references (leaves 227-232). Also available via World Wide Web.