Дисертації з теми "Oxidized system"

Macrophage death is likely to contribute to the transformation of fatty streaks into advanced atherosclerotic lesions. Previous work in the laboratory showed that OxLDL promotes cell death in human macrophages by a mechanism involving intracellular peroxide formation. Here we show that glutathione depletion induced by OxLDL occurs independent of peroxyl radical formation. Our data suggest that the depletion of glutathione is the fundamental defect that renders macrophages susceptible to OxLDL-induced cell injury, but alone is not sufficient to kill macrophages. We indicate that increased protein-Sglutathionylation is involved in OxLDL-induced macrophage death. A potentiation of OxLDL toxicity was observed in macrophages transfected with siRNA directed against either glutathione reductase or glutaredoxin. Our data suggests that OxLDL-induced cell injury in human macrophage is mediated by the depletion of GSH, a decreased in the GSH/GSSG ratio and peroxyl radical formation. All three signals are required for OxLDL-induced macrophage death. Our results also show that the glutathione reductase/glutaredoxin system protects macrophages from OxLDL-induced cell death.

Apoptosis is a crucial process in multicellular organisms in sculpting them, especially during embryogenesis. In addition, apoptosis is responsible for the clearance of harmful or damaged cells which can otherwise be detrimental to the organism. The Bcl-2 family proteins are key players in the regulation of the intrinsic pathway of the apoptotic machinery. This family consists of three subfamilies with B-cell CLL/lymphoma 2 (Bcl-2) protein itself representing anti-apoptotic members, the Bcl-2-associated X protein (Bax), and pro-apoptotic BH3-only signaling proteins. The interplay between pro- and anti-apoptotic proteins on the mitochondrial membranes is central to the balance between the life and death decision of whether the membrane should be permeabilized or not. The cytosolic Bax protein can upon cellular stress translocate to the mitochondrial membrane where it can either carry out its action of forming homo-oligomers that cause outer membrane permeabilization or be inhibited there by the anti-apoptotic membrane protein Bcl-2. Upon mitochondrial outer membrane permeabilization (MOMP) apoptogenic factors leak out from the intermembrane space (IMS) of the mitochondria, leading to caspase activation and ultimately cell death. A common stress signal initiating apoptosis is an increased formation of reactive oxygen species (ROS in the mitochondria, who can cause oxidative damage to lipid membranes. This membrane damage presumably influences the lipid landscape and the membrane features and hence the interactions of the Bcl-2 family proteins with each other and the mitochondrial outer membrane (MOM). To investigate the significance of membrane oxidation on the behavior of the Bcl-2 family proteins, especially Bax, synthetically produced oxidized phospholipids (OxPls) were incorporated in MOM-mimicking vesicles. Differential scanning calorimetry (DSC), nuclear magnetic resonance (NMR) spectroscopy and circular dichroism (CD) spectroscopy revealed a major perturbation in membrane organization in the presence of OxPls. These changes in membrane properties increase the affinity of Bax to its target membrane and enable its partial penetration and formation of pores, as fluorescence leakage assays confirmed. However, in the absence of BH3-only proteins these pores are not sufficiently large for the release of apopototic factors such as cytochrome C (CytC). To understand the inhibition of Bax by the full-length Bcl-2 protein, suitable detergent solubilizing conditions were carefully chosen to enable the measurement of their direct binding to each other outside the membrane, by an antimycin A2 fluorescence assay. The observed protein-protein interaction was confirmed by surface plasmon resonance (SPR). An established protocol for the reconstitution of Bcl-2 into stable proteoliposomes now paves the way for structural studies of this key protein, in its membrane environment near physiological conditions; information essential for understanding its function, on a molecular level, and its potential as a cancer drug target.

Дисертація на здобуття наукового ступеня доктора технічних наук за спеціальністю 05.17.11 – технологія тугоплавких неметалічних матеріалів. – Національний технічний університет “Харківський політехнічний інститут”, Харків, 2005. Дисертація присвячена розробці наукової концепції створення вогнетривких та жаростійких неформованих матеріалів на основі композицій системи RO – R₂O₃ – RO₂ – P₂O₅. Досліджено субсолідусну будову чотирикомпонентних систем: M–A–S–P, C–А–S–P, Zn–Z–S–B, Zn–A–Z–S, C–M–S–P, A–Z–S–P, M–Z–S–P, C–A–S–B, C–A–Z–S, C–M–A–S, C–Sr–A–Z. Визначено співіснуючі фази в системах, виконано триангуляцію потрійних підсистем та тетраедрацію чотирикомпонентних систем, визначено їх об’єми та ступінь асиметрії, побудовано топологіч-ний граф взаємозв’язку елементарних тетраедрів, надано геометро-топологічну характеристику фаз систем, проведено оцінку евтектичних температур в перерізах систем та побудовано поверхні ліквідусу перетинів. На підставі фізико-хімічних досліджень систем розроблено принципи одержання нових вогнетривких та жаростійких неформованих матеріалів. Розроблені нові склади вогнетривких теплоізоляційних матеріалів, жаростійких та вогнетривких цементів та бетонів на їх основі, набивних мас з високими фізико-механічними та технічними властивостями. Встановлено закономірності фазоутворення, та розроблено принципи одержання цих матеріалів.
Thesis for Doctor of Technical Sciences degree on the speciality 05.17.11 – technology of refractory not metal materials. – National Technical University “Kharkiv Polytechnic Institute”, Kharkiv, 2005. The thesis is devoted to develop scientific conception of creation of fire-resistant and heat resisting materials on the basis of the system RO – R₂O₃ – RO₂ – P₂O₅ compositions. The sub-solidus structure of the four component systems has been investigated: M–A–S–P, C–А–S–P, Zn–Z–S–B, Zn–A–Z–S, C–M–S–P, A–Z–S–P, M–Z–S–P, C–A–S–B, C–A–Z–S, C–M–A–S, C–Sr–A–Z. The co-existed phases in the systems have been determined, the tetrahedra for quaternary systems have been carried out, the volumes elementary tetrahedrons have been determined, the topological characteristic of phases of systems have been given. On the basis of physic-chemical researches of the systems the principles of reception new fire-resistant and heat resisting unforming materials have been developed. New compositions of materials on the base of refractories and cements with high physical, mechanical and technical properties have been developed. The principles of phase-formation have been set up and the principles of obtaining these materials have been worked out.

Cardiovascular diseases are considered the first cause of death in westernized societies. They are directly linked to atherosclerosis, a clinical condition characterized by a thickening of the arterial wall. Atherosclerosis is in his turn linked to various genetic and environmental factors; among those factors are high oxidized LDL levels and endothelial dysfunction. In the present study, we have analyzed in vitro the effect of myeloperoxidase oxidized LDL on endothelial cells at the level of fibrinolysis and cell motility.

In the first part of the work, we measured fibrinolysis in real time at the surface of endothelial cells. Our results suggest that myeloperoxidase oxidized LDL interferes with the regulation of fibrinolysis by endothelial cells by decreasing their pro-fibrinolytic activity. This effect was not related to a modification in expression of major regulators of fibrinolysis such as PAI-1 and t-PA. Our data link the current favorite hypothesis that oxidized LDL has a causal role in atheroma plaque formation with an old suggestion that fibrin may also play a causal role. A model that best explains our results would be as follows: oxidized LDL increases fibrin deposition on endothelial cells which will increase their permeability resulting in more oxidized LDL infiltration into the subendothelial space of the arterial wall initiating atherogenesis.

In the second part of the work, we investigated the effect of myeloperoxidase oxidized LDL at the level of endothelial cell motility. We have shown that oxidized LDL is able to decrease cell migration, wound healing and tubulogenesis in endothelial cells. Those effects were not associated with any alteration at the level of neither cell viability nor proliferation. Subsequent gene expression analyses enabled us to link the oxidized LDL induced phenotypical changes in the cells to a change in expression of both microRNA-22 and Heme Oxygenase 1 genes. Our observations suggest a novel role of oxidized LDL not only as an important factor in the initiation of atheromatous lesions, but also as a potential player in the progression of the atherosclerosis disease by impeding blood vessel repair and wound healing at the sites of lesions.

Doctorat en Sciences
info:eu-repo/semantics/nonPublished

A hybrid thruster system utilizes propellants in two different stages, traditionally a solid fuel and a gaseous or liquid oxidizer. Recently hybrid thrusters have become a popular topic of research due to the high demand of a ”green” replacement for hydrazine. Not only are hybrid thruster systems typically much safer than hydrazine, but they are also a low-cost system with a high reliability in performance. The Propulsion Research Laboratory (PRL) at Utah State University (USU) has developed a hybrid thruster system using 3-D printed acrylonitrile butadiene styrene (ABS) as the fuel and gaseous oxygen (GOX) as the oxidizer. This system has been spaceflight flown and tested in a hard vacuum environment with success. However, GOX has a low density and must be stored at high pressures to be considered viable. This thesis investigates the use of N2O/O2 mixtures, ”Nytrox”, and more commonly known as ”laughing gas”, as a higher density replacement oxidizer for GOX. Ina manner directly analogous to the creation of soda-water using dissolved carbon dioxide, Nytrox is created by bubbling gaseous oxygen under high pressure into nitrous oxide until the solution reaches saturation level. Oxygen in the mixture ullage dilutes the nitrous oxide vapor, and increases the required decomposition activation energy of the fluid by several orders of magnitude. Data from tests using each oxidizer are analyzed and presented for performance comparisons. Comparisons include, ignition reliability, ignition energy, thrust coefficient, characteristic velocity, specific impulse, and regression rate. Nytrox is shown to work effectively as a “drop in” replacement for gaseous oxygen, exhibiting slightly reduced specific impulse and regression rate, but with the trade of a significantly higher volumetric efficiency.

This study investigated the influence of dietary antioxidants and quality of oil on the oxidative and enzymatic properties of chicken broiler meat stored in an oxygen-enriched package (HiOx: 80% O2/20% CO2) in comparison with air-permeable polyvinylchloride (PVC) or skin (SK) packaging systems during retail display 2–4 °C for up to 14, 7, and 21 d, respectively. Broilers were fed a diet either with a low-oxidized oil (peroxide vale POV 23 meq O2/kg) or with a high-oxidized oil (POV 121 meq O2/kg), supplemented with an antioxidant pack (200 ppm EconomasE and organic minerals Se, Zn, Cu, Mn, and Fe as in Bioplex) in substitution for vitamin E and inorganic minerals for 42 d. In all packaging systems, lipid oxidation and protein oxidation were inhibited by up to 65% with an antioxidant-supplemented diet when compared to diets without antioxidant supplements. Antioxidant enzyme activities were significantly higher (P < 0.05) in the antioxidant-supplemented diets compared with control diets, regardless of oil quality. Meat samples from the antioxidant-supplemented group, irrespective of oil quality, has less purge and cooking loss compared to control diets. In all packaging systems, meat shear force was higher (P < 0.05) for broilers fed high-oxidized diets than the low-oxidized groups. Comparison between muscle types (breast as white vs. thigh as red) showed a similar trend in muscle susceptibility to oxidized oil in the diet but greater protection of antioxidant supplements for thigh meat in both physiochemical and textural properties. Dietary regimen influenced protein expression in broiler breast meat. Three protein spots from 2-dimensional gel electrophoresis, identified by mass spectrometry as glyceraldehyde 3-phosphate dehydrogenase, creatine kinase, and heat shock protein beta-1 were over-abundant in muscle from low-oxidized diets. The differential proteomes that suggested down regulation of the genes encoding antioxidative proteins upon feeding oxidized oil may be implicated in the broiler meat quality deterioration during storage. In summary, feeding diets with poor oil quality increased the vulnerability of lipids and proteins to oxidation in broiler breast and thigh meat during refrigerated and / or frozen storage in various packaging conditions, yet these effects were alleviated upon dietary supplementation with antioxidants.

У дисертації наведено результати досліджень, спрямованих на розвиток теоретичних основ і технологій очищення безкисневих (природних і технологічних) газів від H2S хінгідронними окисними системами (ХОС) з одержанням сірки. Досліджено взаємну розчинність інгредієнтів хінгідронного поглинального розчину (ХПР) та їх вплив на фізико-хімічні властивості розчину. Теоретично обґрунтовано вибір масообмінної апаратури для процесів хемосорбції H2S на стадії очищення газів та О2 на стадії регенерації поглинального розчину. Досліджено вплив умов формування ХОС на її окисно-відновні та фізико-хімічні властивості, що дало змогу вдосконалити технологію приготування поглинального розчину для очищення безкисневих газів від H2S. Вивчено фазову рівновагу в системі H2S - хінгідронний поглинальний розчин. Досліджено вплив різних факторів на хемосорбцію H2S з безкисневих газів і О2 з повітря ХПР у диспергуючих і барботажних абсорберах. Встановлено вплив вуглеводневих компонентів, які містяться у природних і технологічних газах, на хемосорбцію H2S та регенерацію ХПР. Досліджено процеси електрохімічної регенерації ХПР. Розроблено варіанти технологічних схем для очищення природних і технологічних газів від H2S з одержанням дрібнодисперсної сірки і можливістю комбінування цих технологій з технологією полімерної сірки, що підвищує економічну ефективність хінгідронного процесу знесірчення газів. В диссертации представлены результаты исследований, направленных на развитие теоретических основ и технологий очистки бескислородных (природных и технологических) газов от H2S хингидронными окислительными системами (ХОС) с получением серы. Исследованы взаимная растворимость ингредиентов хингидронного поглотительного раствора (ХПР) и их влияние физико-химические свойства раствора. Теоретически обоснован выбор массообменной аппаратуры для процессов хемосорбции H2S на стадии очистки газов и О2 на стадии регенерации поглотительного раствора. Исследовано влияние условий формирования ХОС на их окислительно-восстановительные и физико-химические свойства, что позволило усовершенствовать технологию приготовления ХПР для очистки бескислородных газов от H2S. Изучено фазовое равновесие в системе H2S – ХПР. Исследовано влияние различных факторов на хемосорбцию H2S из бескислородных газов и О2 из воздуха ХПР в диспергирующих и барботажных абсорберах. Установлено влияние углеводородных компонентов, содержащихся в природных и технологических газах, на хемосорбцию H2S и регенерацию ХПР. Исследованы процессы электрохимической регенерации ХПР. Разработаны варианты технологических схем для очистки природных и технологических газов от H2S с получением тонкодисперсной серы и возможностью комбинирования этих технологий с технологией полимерной серы, что повышает экономическую эффективность хингидронного процесса очистки газов. The dissertation presents the results of research aimed at the development of theoretical foundations and technologies for the purification of oxygen-free (natural and technological) gases from H2S by quinhydrone oxidizing systems (QOS). The resources and composition of hydrogen sulfide-containing gases that need purification and can be raw materials for the production of sulfur or its compounds have been monitored. It is shown that the current technologies of gas purification often do not provide complete purification of gases from H2S, its utilization, are complex, energyintensive, obsolete, and need improvement. The stages of the quinhydrone method of gas purification from H2S, which has experience in industrial applications, but only for the purification of ventilation (oxygen-containing) gases, are analyzed. It is shown that to adapt the method for purification of oxygen-free (natural and technological) gases, it is first necessary to take measures to reduce the negative impact of the oxidation reaction of chemisorbed H2S with O2, accompanied by Na2S2O3 formation, its accumulation, and subsequent processes of waste thiosulfates. The mutual solubility and physicochemical properties of the solution at high concentrations of ingredients in quinhydrone absorbing solution (QAS) were studied. On their basis, theoretical calculations were performed and the choice of mass transfer apparatus was substantiated, which most closely corresponds to the physicochemical bases of oxygen-free gas purification. For purification of gases under atmospheric pressure at the stages of chemisorption of H2S and O2, a horizontal absorber with bucket-shaped dispersants (HABD) is recommended, and for purification under pressure - bubble absorbers. The influence of the conditions of QOS formation on its redox and physicochemical properties has been studied. It is shown that the preparation of QAS based on QOC makes it possible to improve the technology of oxygen-free gases purification from H2S and obtain a given additional product. The phase equilibrium in the H2S - QAS system at different Na2CO3 concentrations was studied. It was found that the phase distribution coefficient mpx increases sharply with increasing saturation of the solution and decreases with increasing Na2CO3 concentration. The equilibrium constant of the H2S chemisorption reaction depends on the initial concentration of Na2CO3 and is equal to 0.1…0.35 mol/(m3.Pa). These data were used to develop a two-stage gas purification scheme. Using the criterion equations and the results of phase equilibrium studies, a mathematical model of H2S chemisorption from gases by QAS in the bubbling model was developed, which takes into account the influence of gas pressure and saturation of H2S solution at different Na2CO3 concentrations. The influence of various factors on the chemisorption of H2S from oxygen-free gases of QAS in bubbling and mechanical dispersing absorbers has been experimentally investigated. It is established that at low degrees of saturation of H2S solution in bubble absorbers the resistance of the system is determined by the resistance from the gas phase. The increase in pressure naturally contributes to the growth of the driving force of the chemisorption process of H2S by QAS. The rate of chemisorption increases with increasing pressure in proportion to Pn (n=0.82…0.83), which is characteristic of systems with "moderately soluble" gas, i.e. those that are limited by resistance from both gas and liquid phases. The value of the linear velocity of the disperser bucket ends (12 m/s) in the HABD was established, at which the resistance from the gas phase has a decisive influence on the kinetics of H2S chemisorption from oxygen-free gases. At the same time, the lowest resistance from the gas phase is achieved at the maximum gas velocities in the absorber 1.8...2.0 m/s. Using the criterion equations, the process of O2 chemisorption from QAS air at the stage of its regeneration in a vertical apparatus with a continuous bubbling layer (VABL) was calculated. The influence of various factors on this process in two types of absorbers - VABL and HABD is experimentally investigated. It is established that the rate of O2 chemisorption of QAS in VABL devices increases with increasing airflow. However, the rate of the chemical reaction between chemisorbed O2 and the reductive form of QOC is much higher (310…430 times) than the rate of O2 chemisorption. Therefore, this type of mass transfer equipment is not recommended for the regeneration of QAS by air oxygen. It is shown that the selective oxidation of chemisorbed H2S with the formation of fine sulfur during electrochemical regeneration of the absorption solution is achieved at low current densities (up to 15…17 A/dm2 ) and the process duration is up to 5 min. At higher densities, due to the increase in pH, by-products are formed (mainly Na2S2O3 and Na2SO4), which impair the sorption properties of QAS. During the electrochemical regeneration of QAS, competing processes of oxidation of chemisorbed H2S and reductive forms of QOC take place, which reduces the efficiency of solution regeneration. In the absence of sulfur compounds in QAS during electrochemical regeneration, the concentration of oxidative forms of QOS increases by 12…30%. It is shown that the decrease in the chemisorption degree of H S when using absorption solutions with a high concentration of Na2S2O3 (up to 350 kg/m3 ) can be compensated by a slight increase in temperature up to 303...308K. This will directly use waste solutions as raw materials for polymer sulfur obtaining. The pH limits (not higher than 8.8… 8.9) are set, at which fine sulfur is obtained with a high yield during gas purification. This is due to the relatively high concentration of NaHCO3 compared to Na2CO3 in the absorbing solution. Variants of technological schemes for purification of natural, associated, coke, pyrolysis, bio, and other gases with the production of fine sulfur and the possibility of combining these technologies with polymeric sulfur technology, which increases the economic efficiency of quinhydrone method gas desulfurization process.

A spin-cast silicone membrane has been successfully bonded between two injection-molded microstructured plastic discs. This sandwich structure creates a useful platform for mass production of microfluidic systems, provided that the bonds are leakproof. The bonds were achieved by a silicon dioxide coating deposited on the plastic discs by evaporation. This investigation is concerned with the process and the result only, no theory is discussed.

Ng Chi Ho.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2005.
Includes bibliographical references (leaves 147-160).
Abstracts in English and Chinese.
ACKNOWLEDGMENTS --- p.I
ABSTRACT --- p.II
LIST OF ABBREVIATIONS --- p.VII
TABLE OF CONTENTS --- p.IX
Chapter CHAPTER 1 --- GENERAL INTRODUCTION
Chapter 1.1 --- Introduction of Low-density lipoprotein --- p.1
Chapter 1.1.1 --- What are lipids? --- p.1
Chapter 1.1.2 --- Function and structure of cholesterol --- p.1
Chapter 1.1.3 --- Function and classification of lipoprotein --- p.1
Chapter 1.2 --- Functions of low-density lipoprotein --- p.2
Chapter 1.3 --- Basic structure of low-density lipoprotein --- p.4
Chapter 1.4 --- Principle on isolation and purification of low-density lipoprotein --- p.4
Chapter 1.5 --- Cholesterol transport system --- p.7
Chapter 1.5.1 --- Exogenous pathway of cholesterol metabolism --- p.7
Chapter 1.5.2 --- Endogenous pathway of cholesterol metabolism --- p.7
Chapter 1.5.3 --- Reverse transport of Cholesterol --- p.8
Chapter 1.6 --- Oxidation of LDL --- p.10
Chapter 1.6.1 --- Agents that causes oxidation --- p.10
Chapter 1.6.1.1 --- Lipoxygenases --- p.10
Chapter 1.6.1.2 --- Myeloperoxidase --- p.10
Chapter 1.6.1.3 --- Reactive nitrogen species --- p.11
Chapter 1.6.1.4 --- Reactive oxygen species --- p.11
Chapter 1.6.2 --- Factors that affect the susceptibility of LDL oxidation --- p.13
Chapter 1.7 --- Hyperlipidaemia 一 chance to increase LDL oxidation --- p.13
Chapter 1.7.1 --- Definition of hyperlipidemia and hypercholesterolemia --- p.13
Chapter 1.7.2 --- Risk factors of hyperlipidaemia --- p.13
Chapter 1.7.2.1 --- High fat low fibre diets: --- p.13
Chapter 1.7.2.2 --- Obesity --- p.14
Chapter 1.7.2.3 --- Type II diabetes --- p.14
Chapter 1.7.2.4 --- Genetic factors (Familial hyperlipidemias) --- p.14
Chapter 1.8 --- Diseases related to oxidized LDL --- p.15
Chapter 1.8.1 --- Cardiovascular diseases --- p.15
Chapter 1.8.1.1 --- Atherosclerosis and ischemic heart attack --- p.15
Chapter 1.8.1.2 --- Factors that affect incidence of atherosclerosis --- p.16
Chapter 1.8.1.2.1 --- Triglyceride-rich lipoprotein --- p.16
Chapter 1.8.1.2.2 --- Small and dense LDL --- p.16
Chapter 1.8.1.3 --- Stroke --- p.17
Chapter 1.8.2 --- Common ways to reduce plasma cholesterol level --- p.17
Chapter 1.8.2.1 --- Diet control --- p.17
Chapter 1.8.2.2 --- Physical activity --- p.17
Chapter 1.8.2.3 --- Drug therapy --- p.18
Chapter CHAPTER 2 --- IMPAIRMENT OF OXIDIZED LDL ON ENDOTHELIUM-DEPENDENT RELAXATION
Chapter 2.1 --- Introduction --- p.19
Chapter 2.1.1 --- Properties and function of phenylephrine hydrochloride --- p.22
Chapter 2.1.2 --- Properties and function of acetylcholine --- p.22
Chapter 2.2 --- Objectives --- p.23
Chapter 2.3 --- Materials and methods --- p.24
Chapter 2.3.1 --- Preparation of drugs --- p.24
Chapter 2.3.2 --- Preparation of human native LDL --- p.25
Chapter 2.3.3 --- Preparation of oxidized LDL --- p.27
Chapter 2.3.4 --- Preparation of aorta --- p.27
Chapter 2.3.5 --- Measurement of Isometric Force in vitro --- p.30
Chapter 2.3.5.1 --- Protocol 1- Dose effect of oxidized LDL on acetylcholine-induced vasorelaxation --- p.30
Chapter 2.3.5.2 --- Protocol 2 - Time effect of oxidized LDL on acetylcholine-induced vasorelaxation --- p.30
Chapter 2.3.5.3 --- Protocol 3 - Effect of co-incubation of LDL and copper(ll) sulphate on acetylcholine-induced vasorelaxation --- p.31
Chapter 2.3.5.4 --- Protocol 4 - Effect of oxidized LDL on selected vasodilators --- p.32
Chapter 2.3.5.5 --- Protocol 5 - Effect of pretreatment of L-arginine on oxidized LDL impaired -endothelium-induced relaxation --- p.32
Chapter 2.3.5.6 --- Protocol 6 - Effect of a -tocopherol on oxidized LDL-damaged acetylcholine- induced vasorelaxation --- p.33
Chapter 2.3.5.7 --- Protocol 7 - Effect of a -tocopherol on LDL and copper(ll) sulphate- induced endothelial dysfunction --- p.33
Chapter 2.3.6 --- Western blot analysis of endothelial nitric oxide synthase (eNOS) protein --- p.34
Chapter 2.3.7 --- Statistics --- p.35
Chapter 2.4 --- Results --- p.36
Chapter 2.4.1 --- Dose effect of oxidized LDL on acetylcholine-induced vasorelaxation --- p.36
Chapter 2.4.2 --- Time effect of oxidized LDL on acetylcholine-induced vasorelaxation --- p.36
Chapter 2.4.3 --- Effect of co-incubation of LDL and copper(II) sulphate on acetylcholine- induced vasorelaxation --- p.39
Chapter 2.4.4 --- Effect of oxidized LDL on selected vasodilators --- p.41
Chapter 2.4.5 --- Effect of pretreatment of L-arginine on oxidized LDL impaired- acetylcholine-induced relaxation --- p.41
Chapter 2.4.6 --- Effect of a-tocopherol on oxidized LDL-damaged acetylcholine- induced vasorelaxation --- p.48
Chapter 2.4.7 --- Effect of a-tocopherol on LDL and copper(II) sulphate-induced endothelial dysfunction --- p.50
Chapter 2.4.8 --- eNOS Protein expression --- p.50
Chapter 2.5 --- Discussion --- p.53
Chapter CHAPTER 3 --- EFFECTS OF LDL INJECTION ON THE ENDOTHELIAL FUNCTION OF RATS
Chapter 3.1 --- Introduction --- p.58
Chapter 3.2 --- Objective --- p.60
Chapter 3.3 --- Methods and Materials --- p.61
Chapter 3.3.1 --- Preparation of Drugs --- p.61
Chapter 3.3.2 --- Preparation of LDL --- p.61
Chapter 3.3.3 --- Animal Treatment --- p.61
Chapter 3.3.4 --- Serum lipid and lipoprotein determinations --- p.62
Chapter 3.3.5 --- Measurement of serum MDA level by TBARS assay --- p.62
Chapter 3.3.6 --- Preparation of aorta --- p.62
Chapter 3.3.7 --- Organ bath experiment --- p.63
Chapter 3.3.8 --- Statistics --- p.64
Chapter 3.4 --- Result --- p.65
Chapter 3.4.1 --- Growth and food intake --- p.65
Chapter 3.4.2 --- "Effect of LDL injection on serum TC, TG and HDL-C" --- p.65
Chapter 3.4.3 --- Effect of LDL injection on non-HDL-C and ratio of non-HDL-C to HDL-C --- p.65
Chapter 3.4.4 --- Serum MDA level --- p.68
Chapter 3.4.5 --- Phenylephrine-induced contraction --- p.70
Chapter 3.4.6 --- Endothelium-dependent and -independent relaxation --- p.75
Chapter 3.5 --- Discussion --- p.79
Chapter CHAPTER 4 --- EFFECTS OF INDIVIDUAL COMPONENT OF OXIDIZED LDL ON ENDOTHELIUM-DEPENDENT RELAXATION
Chapter 4.1 --- Introduction --- p.83
Chapter 4.2 --- Objectives --- p.85
Chapter 4.3 --- Materials and methods --- p.86
Chapter 4.3.1 --- Preparation of drugs --- p.86
Chapter 4.3.2 --- Preparation of human native LDL and oxidized LDL --- p.86
Chapter 4.3.3 --- GC analysis of fatty acid composition in LDL --- p.86
Chapter 4.3.4 --- TBARS assay analysis of MDA content in LDL --- p.87
Chapter 4.3.5 --- GC analysis of cholesterol oxidation products in LDL --- p.89
Chapter 4.3.6 --- Thin-layer chromatography analysis of LPC in LDL --- p.91
Chapter 4.3.7 --- Preparation of aorta --- p.92
Chapter 4.3.8 --- Measurement of Isometric Force in vitro --- p.92
Chapter 4.3.8.1 --- Protocol 1- effect of LPC on acetylcholine-induced vasorelaxation --- p.92
Chapter 4.3.8.2 --- Protocol 2- effect of cholesterol oxidation products on acetylcholine-induced vasorelaxation --- p.92
Chapter 4.3.8.3 --- Protocol 3- effect of oxidized fatty acids on acetylcholine-induced vasorelaxation --- p.93
Chapter 4.3.9 --- Statistics --- p.93
Chapter 4.4 --- Results --- p.94
Chapter 4.4.1 --- Compositional differences between native LDL and oxidized LDL.… --- p.94
Chapter 4.4.2 --- Effect of LPC on endothelium-dependent relaxation --- p.98
Chapter 4.4.3 --- Effect of COPs on endothelium-dependent relaxation --- p.98
Chapter 4.4.4 --- Effect of oxidized fatty acids on endothelium-dependent relaxation --- p.101
Chapter 4.5 --- Discussion --- p.103
Chapter CHAPTER 5 --- EFFECTS OF DIETARY OXIDIZED CHOLESTEROL ON BLOOD CHOLESTEROL LEVEL IN HAMSTERS
Chapter 5.1 --- Introduction --- p.107
Chapter 5.2 --- Objectives --- p.111
Chapter 5.3 --- Materials and Methods --- p.112
Chapter 5.3.1 --- Preparation of Oxidized Cholesterol --- p.112
Chapter 5.3.2 --- Diet preparation --- p.112
Chapter 5.3.3 --- Animals --- p.113
Chapter 5.3.4 --- Serum lipid and lipoprotein determinations --- p.116
Chapter 5.3.5 --- GC analysis of cholesterol and cholesterol oxidation products on organs --- p.116
Chapter 5.3.6 --- Extraction of neutral and acidic sterols from fecal samples --- p.117
Chapter 5.3.6.1 --- Determination of neutral sterols --- p.117
Chapter 5.3.6.2 --- Determination of acidic sterols --- p.117
Chapter 5.3.6.3 --- GLC analysis of neutral and acidic sterols --- p.118
Chapter 5.3.7 --- Organ bath experiment --- p.121
Chapter 5.3.7.1 --- Preparation of aorta --- p.121
Chapter 5.3.7.2 --- Aortic relaxation --- p.121
Chapter 5.3.8 --- Analysis of the total area of atherosclerotic plaque on aorta --- p.122
Chapter 5.3.9 --- Statistics --- p.122
Chapter 5.4 --- Results --- p.123
Chapter 5.4.1 --- GC of oxidized cholesterol --- p.123
Chapter 5.4.2 --- Growth and food intake --- p.123
Chapter 5.4.3 --- "Effect of non-oxidized and oxidized cholesterol on serum TC, TG and HDL-C" --- p.123
Chapter 5.4.4 --- Effect of non-oxidized and oxidized cholesterol on non-HDL-C and ratio of non-HDL-C to HDL-C --- p.124
Chapter 5.4.5 --- Effect ofnon-oxidized and oxidized cholesterol on concentration of hepatic cholesterol --- p.128
Chapter 5.4.6 --- Effect of non-oxidized and oxidized cholesterol on concentration of cholesterol oxidation products accumulated in liver --- p.128
Chapter 5.4.7 --- Effect of non-oxidized and oxidized cholesterol on concentration of brain and aortic cholesterol --- p.128
Chapter 5.4.8 --- Effect of non-oxidized and oxidized cholesterol on fecal neutral and acidic sterols --- p.129
Chapter 5.4.9 --- Effect of non-oxidized and oxidized cholesterol on aortic relaxation --- p.135
Chapter 5.4.10 --- Effect of non-oxidzied and oxidized cholesterol on area of atherosclerotic plaque --- p.137
Chapter 5.5 --- Discussion --- p.139
Chapter CHAPTER 6 --- CONCLUSION --- p.143
REFERENCES --- p.146

Perchlorate has entered human and environmental food chains and has received a great deal of attention because of its toxicity to humans. In this study, chemical degradation of perchlorate was investigated using partially oxidized titanium ions (Ti2+ and Ti3+) in solutions and as part of an ion exchange membrane reactor system. Aqueous titanium ions (Ti2+ and Ti3+) were applied to remove perchlorate ions and its destructive mechanism, reaction kinetics, and the effect of environmental factors were investigated. Titanium ions were able to degrade perchlorate ions very rapidly with half life less than one hour under conditions of high acid concentrations. A new reactor system with an ion exchange membrane was adapted to apply better the reactions of perchlorate destruction to water treatment practice. A novel treatment method was developed by integrating partially oxidized titanium ions with an ion exchange membrane, and it is named the Titanium and Membrane Hybrid System (TMH System). The results shown in this research demonstrate the feasibility of TMH System for perchlorate reduction. The perchlorate ions were rapidly adsorbed onto the ion exchange membrane and diffused through it, but they were reduced by titanium ions in the degradation zone relatively slowly. To enhance the overall rate of reaction, high concentrations of acid and Ti(III) are needed, but transport of hydrogen ions through the anion permeable membrane was observed and would be greater at higher acid concentrations. The proposed mathematical model predicts the performance and behavior of the TMH system for different physical and chemical conditions. It successfully described adsorption, diffusion and reduction of perchlorate in the system. This model could be used as an important tool for process design and optimization.

Elevated plasma concentrations of lipoprotein(a) (Lp(a)) are associated with increased risk of atherothrombotic disease. Lp(a) is a unique lipoprotein consisting of a low density lipoprotein-like moiety covalently linked to apolipoprotein(a) (apo(a)), a homologue of the fibrinolytic proenzyme plasminogen. Apo(a) is extremely heterogeneous in size with small isoforms being independently associated with increased cardiovascular risk. Several in vitro and in vivo studies have shown that Lp(a)/apo(a) can inhibit tissue-type plasminogen activator (tPA)-mediated plasminogen activation on fibrin surfaces, although the mechanism of inhibition by apo(a) remains controversial. Essential to fibrin clot lysis are a number of plasmin-dependent positive feedback reactions that enhance the efficiency of plasminogen activation, including the plasmin-mediated conversion of Glu1-plasminogen to Lys78-plasminogen. Additionally, abnormal fibrin clot structures have been associated with both an increased risk of cardiovascular disease and elevated Lp(a) levels. Similarly, oxidized phospholipids have been implicated in the development of cardiovascular disease, and are not only preferentially carried by Lp(a) in the plasma but have also been shown to covalently-modify both apo(a) and plasminogen. In this thesis, we built upon the understanding of the role of apo(a) in plasminogen activation on the fibrin/degraded fibrin surface by determining that: (i) apo(a) inhibits plasmin-mediated Glu1-plasminogen to Lys78-plasminogen conversion and identifying the critical domains in apo(a) responsible for this effect, (ii) apo(a) isoform size does not affect either the inhibition of tPA-mediated plasminogen activation or the inhibition of plasmin-mediated Glu1-plasminogen to Lys78-plasminogen conversion, (iii) apo(a) modifies fibrin clot structure to form more dense clots with thinner fibers and reduced permeability, modifications that enhance the ability of apo(a) to inhibit tPA-mediated plasminogen activation and (iv) the phosphorus content of apo(a) affects its ability to inhibit tPA-mediated plasminogen activation and the phosphorus content of plasminogen affects its ability to be activated by tPA. By understanding these individual reactions, each of which has the potential to affect the broader fibrin clot lysis process, we have expanded our understanding of the overall effect of Lp(a)/apo(a) in the inhibition of plasminogen activation on the fibrin/degraded fibrin surface and thus broadened our understanding of how Lp(a)/apo(a) may mediate the inhibition of thrombolysis in vivo.
Thesis (Ph.D, Biochemistry) -- Queen's University, 2011-12-14 08:26:54.99

碩士
國立中山大學
環境工程研究所
104
This study investigated the treatment of volatile organic compounds (VOCs) emitted from resin production at a factory in Yong-An Industrial Park, Taiwan. Originally treated with a direct-fired thermal oxidizer (TO) that uses fuel oil as the fuel source, the VOCs was subsequently treated with a regenerative thermal oxidizer (RTO) that uses liquefied natural gas as the fuel in order to investigate the changes in destruction and removal efficiency (DRE) for VOCs as well as the energy-saving efficiency of the RTO as a result of a change in the type of fuel used. An auto detection method for the concentrations of total hydrocarbon and total nonmethane hydrocarbon in exhaust pipes developed by the Environmental Protection Administration was adopted to estimate the RTO’s VOC DRE. The RTO attained a VOC DRE of 96.1%, which satisfies the environmental regulations. In addition, the RTO achieved an energy-saving efficiency of 195% by using gas instead of fuel oil, and the annual fuel expenses and CO2 emissions were reduced by approximately NT$2.74 million and 539 ton, respectively.

碩士
國立交通大學
工學院永續環境科技學程
100
The zeolite rotor/oxidizer system for organic waste gas emission reduction is an advanced air pollution control device (APCD) which is widely applied in many high-tech. industry plants. However it is often under the conflict situation between operation efficiency and the operating costs. In this study, the six standard deviations method which uses the D-M-A-I-C (Define-Measure-Analyze-Improve-Control) approach to improve the system operation is employed. It has incorporated the characteristic figure、Plato figure、effect figure、SPC and other quality control charts as well as Minitab software as tools for understanding, optimizing and improving the operation condition. This would help in improving the process efficiency of a zeolite rotor/oxidizer while reducing the operating cost at the same time. Research results show that there are a total of 15 factors influencing the operation efficiency and fuel consumption. By using quality analysis charts and regression analysis, it converges to 3 major factors, inverter frequency of desorption fan, desorption temperature and combustion temperature. The 3 factors have a major effect on the operation efficiency with contribution of as high as 92.2%; while it is 75.8% on the fuel consumption. And through the Design of Experiment (DOE), it is found that by increasing the frequency of desorption fan and the combustion temperature as well as by decreasing the desorption temperature, both the operation efficiency can be enhanced and the fuel consumption can be reduced. As a result, the optimization condition for the case study shows that desorption fan inverter frequency is 45 Hz, the combustion temperature is 710℃ and the desorption temperature is 200℃. This yields that the organic emission is reduced by 14% from 0.28 kg/hr to 0.24 kg/hr; the operation efficiency was enhanced by 1% from 95.9% to 96.9%. The Fuel consumption was cut by 4.4% from 25 m3/hr to 23.9 m3/hr.

The understanding of the luminescence properties of silicon at nanoscale is a relevant subject for the development of new light emitting devices. In this work, the emission features of crystalline silicon nanoparticles is studied. To reveal the role of the surface termination on the photoluminescence properties of silicon nanoparticles with several terminations (hydrogen, silicon oxide or organic molecules) photoluminescence in steady-state and time-resolved modes and measurements of the emission quantum yield were performed. At room temperature, the emission spectra of silicon nanoparticles terminated with hydrogen and functionalized with organic molecules, with average mean diameter of ≈3.4 and ≈2.4 nm present an emission component peaking at ≈800 and ≈750 nm, respectively. This emission component is ascribed to recombination of photogenerated excitons in the silicon core of the nanoparticles. An additional emission component peaking at higher energy, ascribed to the donor-acceptor recombination within states associated with the oxide shell is also present in the spectra of the nanoparticles with an oxide shell. The emission lifetime and quantum yield values depend on the surface termination and are discussed the role of the surface termination int the inter- and intra-nanoparticle exciton transfer. The higher room temperature emission quantum yield was measured for silicon nanoparticles with organic functionalization processed as films (0.23±0.02). Another aspect studied was the homogeneous infilling of films of silicon nanoparticles with Al2O3 using atomic layer deposition. The infilling allows to protect the films against oxidation and also impacts on the photoluminescence emission spectrum of the nanoparticles. This work opens new questions about the role of the surface termination and separation between nanoparticles on the emission properties. Taking advantage from the dependence of the nanoparticles emission on temperature, an innovative primary thermometer was developed. It is shown that luminescent thermometers based on silicon nanoparticles films and solutions can operate in distinct environments with the thermometric parameter (emission peak position) described by a well-established equation. The thermometer has a reversibility and repeatability higher than 99.98% and the maximum relative thermal sensitivity is 0.04 %.K−1.
O entendimento das propriedades de luminescência do silício à escala nanométrica é uma questão relevante para o desenvolvimento de novos dispositivos emissores de luz. Neste âmbito, esta tese foca o estudo das propriedades de emissão de nanopartículas cristalinas de silício, com diferentes terminações da superfície (hidrogénio, óxido de silício ou moléculas orgânicas), utilizando espectroscopia de fotoluminescência em modo estacionário e resolvido no tempo e medidas de rendimento quântico de emissão. À temperatura ambiente, os espectros de emissão das nanopartículas terminadas com hidrogénio e funcionalizadas com moléculas orgânicas, com tamanhos médios de ≈3.4 e ≈2.4 nm, apresentam uma componente centrada, respetivamente em ≈800 e ≈750 nm. Esta componente é atribuída à recombinação de excitões fotogerados no núcleo de silício da nanopartícula. Uma componente adicional, a maiores energias, está presente no espectro de nanopartículas com óxido de silício à superfície, sendo atribuída à recombinação de pares dados-aceitador de estados associados ao óxido. Os valores medidos para os tempos de vida de emissão e para o rendimento quântico de emissão dependem da terminação da superfície e são discutidos, através da transferência de excitões intra- e inter-nanopartículas. O valor mais alto de rendimento quântico de emissão à temperatura ambiente para amostras em filme foi medido para nanopartículas com funcionalização orgânica (0.23±0.02). Uma outra vertente do trabalho, envolveu filmes de nanopartículas de silício infiltrados com Al2O3, utilizando deposição em camadas atómica. A camada depositada permite proteger os filmes contra a oxidação e observa-se uma alteração do espectro de emissão das nanopartículas, relativamente a nanopartículas análogas sem infiltração. Este trabalho abre novas questões sobre o papel da terminação e separação entre nanopartículas no que respeita às propriedades de emissão. Tirando partido da dependência da emissão com a temperatura foi desenvolvido um termómetro primário inovador. Em particular, é mostrado que termómetros luminescentes baseados em nanopartículas de silício processadas em filme e em solução podem operar em diversos ambientes com um parâmetro termométrico (energia do pico de emissão) descrito por uma equação de estado bem estabelecida. O termómetro apresenta uma reversibilidade e repetibilidade superior a 99.98%, e um valor máximo para a sensibilidade térmica relativa de 0.04 %.K−1.
Programa Doutoral em Física

碩士
國立勤益科技大學
冷凍空調與能源系
107
This study focuses on adjusting operation parameters of volatile organic compounds(VOCs) treatment equipment, so as to conduct the optimal adjustment and improvement in a short time, to keep the treatment efficiency above 95% and to efficiently reduce the gas usage. In this study, combined with statistical methods and Minitab statistical software, Taguchi Methodology and the five steps (D-M-A-I-C, namely, definition, measurement, analysis, improvement and control) of Six Sigma are used to explore and analyze the issues of the three-tower type regenerative thermal oxidizer connected zeolite rotor concentrator system(RTO) one by one, including fuel usage and operation costs reduction, and also can keep the treatment efficiency in optimum condition. In this study, the optimal improvement in practical operation of the RTO system is carried out in a TFT-LCD plant of the optoelectronics industry. The results show that a total of 13 factors affect fuel usage and VOCs treatment efficiency. Based on quality analysis chart and regression analysis, 2 main factors including combustion furnace temperature and desorption air flow rate are found. The contribution of the 2 factor to the impact of fuel consumption is as high as 98.76%. Through DOE (Design of Experiment) and regression analysis, lower furnace temperature and lower desorption air flow rate can significantly save fuel usage and hold the optimal running efficiency. The results of practical application in the TFT-LCD plant show that the optimal combination of parameters is to set the combustion furnace temperature at 780℃ and the desorption air driving fan frequency at 41 Hz. When the system operate with this two optimal parameters, the results show that the fuel usage is reduced from 483 m3/day to 411 m3/day, the improvement rate is as high as 14.9%. The treatment efficiency in VOCs is 96.6% and is also higher than the target value of 95%. The electricity consumption of the desorption air driving fan is reduced by 5.5 kW with about 15% improvement. Additionally, the odor threshold value of derivative index is within the expected range 410.

This research assessed the seasonal effects of contrasting tillage and crop rotation systems on soil ammonia oxidizing bacteria (AOB) and archaea (AOA). Four different cropping systems under till and no-till were analyzed in a 30 year-old agricultural field trial. Samples were collected during the 2010 growing season at times corresponding with agronomic events. Nucleic acids were preserved in the field and subsequently analyzed by quantitative real-time polymerase chain reactions (qPCR). Tillage decreased AOB activity and abundance in the plow layer (0-15 cm) immediately after fall moldboard plow events, but observed AOB dynamics at other times suggest tillage had a long-term distribution effect across depth (0-30 cm). AOA abundance was significantly greater in no-till plots at all times indicating tillage had longer-term effects on these communities. Crop rotation had minimal effect on AOB and AOA, but there was a noted yield advantage for corn following wheat, regardless of tillage treatment.
OMAFRA Highly Qualified Personnel Program, NSERC