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  • Thesis


  • Authors: Dixon, James Brandon (2006)

  • Collecting microlymphatics play a vital role in promoting lymph flow from the initial lymphatics in the interstitial spaces to the large transport lymph ducts. In most tissues, the primary mechanism for producing this flow is the spontaneous contractions of the lymphatic wall. Individual units, known as lymphangion, are separated by valves that help prevent backflow when the vessel contracts, thus promoting flow through the lymphatic network. Lymphatic contractile activity is inhibited by flow in isolated lymphatics, however there are virtually no in situ measurements of lymph flow in these vessels. Initially, a high speed imaging system was set up to image in situ preparations at 500 fps. These images were then manually processed to extract information regarding lymphocyte velocity...

  • Thesis


  • Authors: Zhou, Zhengrong (2006)

  • To devise more biocompatible materials for use in blood contacting devices, novel polymers with either nitric oxide (NO) release alone or NO release in concert with surface-bound active heparin have been developed, with the goal of mimicking the non¬thrombogenic properties of the endothelial cell (EC) layer that lines all blood vessels. New NO releasing polymethacrylates with pendant N-diazeniumdiolated alkyldiamine moieties were synthesized and characterized. The NO releasing polymeric coatings were formulated by doping such polymer-based NO donors within PVC and silicone rubber matrices, and employing a biodegradable poly(lactide-co-glycolide) as a harmless proton-generating additive to greatly prolong the NO release of such coatings. Polymer coatings with a desired NO surface fl...

  • Thesis


  • Authors: Oh, Sanghoon (2006)

  • Dispersion caused by the refractive index variation over a spectral range is an important characteristic to identify the structure and composition of materials. This research reports on work to obtain dispersion information using both time and spectral domain optical coherence tomography. To process time-frequency data, a non-uniform Fourier transformation is applied to remove the resolved non-uniform frequency sampling. Analysis of the spectral phase function in the optical frequency domain is applied to measure the dispersion. First, this research experimented with water (H20) to measure dispersion. The measured dispersion of water is compared with known data to confirm the methodology. Second, the concentration of a glucose solution was estimated by analyzing the spectral phase f...

  • Thesis


  • Authors: Park, Woo-Tae (2005)

  • Micromachined accelerometers have been introduced in the late 1970s and have been used in various applications. The applications range from inertial navigation and data logging in wells to body activity monitoring for pacemakers. Although the size of the accelerometers was sufficient for their applications, there were not many efforts in pushing the limits of accelerometer miniaturization. In this study, we utilized film deposition packaging technology and other modern microfabrication techniques to miniaturize the size and mass of the packaged accelerometers, two orders of magnitude smaller than any accelerometers ever reported. We used these ultra miniature accelerometers to offer sensing capabilities for biomedical applications which was not possible with any other means. A nove...

  • Thesis


  • Authors: He, Yuanchen (2006)

  • Due to complexity of biomedical problems, adaptive and intelligent knowledge discovery and data mining systems are highly needed to help humans to understand the inherent mechanism of diseases. For biomedical classification problems, typically it is impossible to build a perfect classifier with 100% prediction accuracy. Hence a more realistic target is to build an effective Decision Support System (DSS). In this dissertation, a novel adaptive Fuzzy Association Rules (FARs) mining algorithm, named FARM-DS, is proposed to build such a DSS for binary classification problems in the biomedical domain. Empirical studies show that FARM-DS is competitive to state-of-the-art classifiers in terms of prediction accuracy. More importantly, FARs can provide strong decision support on disease di...

  • Thesis


  • Authors: Jettmar, Eva (2006)

  • Collecting microlymphatics play a vital role in promoting lymph flow from the initial lymphatics in the interstitial spaces to the large transport lymph ducts. In most tissues, the primary mechanism for producing this flow is the spontaneous contractions of the lymphatic wall. Individual units, known as lymphangion, are separated by valves that help prevent backflow when the vessel contracts, thus promoting flow through the lymphatic network. Lymphatic contractile activity is inhibited by flow in isolated lymphatics, however there are virtually no in situ measurements of lymph flow in these vessels. Initially, a high speed imaging system was set up to image in situ preparations at 500 fps. These images were then manually processed to extract information regarding lymphocyte velocity...

  • Thesis


  • Authors: Martin, Brent R. (2006)

  • The orchestrations that underlie the existence of even the simplest organisms are quite complex and extremely dynamic. In order to gain a greater understanding of the biochemistry underlying many unsolved biological problems, new tools are required to first visualize a phenomenon, and then perturb it to study its significance. Visualizing the dynamics of intracellular biochemistry has been enhanced greatly with widespread adoption of genetically encoded fluorescent proteins. Due to the large size of fluorescent proteins and their lack of chemical flexibility, the tetracysteine-biarsenical system was developed. This technology uses the combination of a short genetically encoded tag and a specific class of exogenous, membrane-permeant dyes. Since its introduction, the biarsenical-tet...

  • Thesis


  • Authors: Vadala, Michael L. (2006)

  • Copolymer -cobalt complexes have been formed by thermolysis of dicobalt octacarbonyl in solutions of copolysiloxanes. The copolysiloxane -cobalt complexes formed from toluene solutions of PDMS - -[PMVS - -PMTMS] block copolymers were annealed at 600 -700 °C u nder nitrogen to form protective siliceous shels around the nanoparticles. Magnetic measurements after aging for several months in both air and in water suggest that the ceramic coatings do protect the cobalt against oxidation. However, after mechanical grinding, oxidation occurs. The specific saturation magnetization of the siliceous -cobalt nanoparticles increased substantialy as a function of annealing temperature, and they have high magnetic moments for particles of this size of 60 emu g-1 Co after h eat-treatment at temper...

  • Thesis


  • Authors: Lewis, Danielle R. (2006)

  • The organization of this Dissertation is as follows. Chapter 1 serves an an introduction to polymer networks. Different types of networks are described, as well as some rele¬vant theoretical models used to characterize such networks. Chapter 2 discusses how different curing processes affect the final network structures of poly(tert-butyl acry¬late) (poly(t-BA)) gels. Specifically, uncovered and covered molds are investigated in order to see how evaporation of the precursor solution effects the final network structure. Different curing temperatures as well as different amounts and qualities of solvents are also explored. Rheological and swelling experiments are used in con-junction with equilibrium swelling theories in order to deduce poly(t-BA) network structure. Chapter 3 discusses...

  • Thesis


  • Authors: Chen, Pei (2006)

  • Medical image reconstruction and medical simulation are active research areas in the field of medical image processing and have received a great deal of attention over the past ten years. Medical image reconstruction allows a physician to visualize the interior organs and tissues of patient 's sbody in a nondestructive or minimally invasive way for improved diagnosis and better treatment selection. Medical simulation can model the biochemical nature, metabolic characteristics, and geometric arrangement of human organs such that the change in these properties can be studied and predicted when the environmental parameters are altered. This dissertation covers two distinct but related areas of work: 1) a maximum a posterior (MAP) tomosynthetic reconstruction for X-ray imaging, and 2) r...