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Glycosylation Of Peanut (Arachis Hypogaea L) Peroxidases, Lianglu Wan
Glycosylation Of Peanut (Arachis Hypogaea L) Peroxidases, Lianglu Wan
Digitized Theses
The cationic (C.PRX) and the anionic (A.PRX) peroxidase isozymes secreted into the medium of cell cultures are both 20% glycosylated proteins. They are stable and occur in high amounts (C.PRX, 5 mg and A.PRX 0.5 mg per litre of spent culture medium), and so provide an ideal system for the study of the effect of glycosylation on the structure and function of glycoproteins.;A novel method to detect glycoproteins and glycopeptides is proposed using periodic-acid Schiff's reagent dot-blotting assay on nitrocellulose membrane. At least 0.1 ug of glycan can be detected within 40 minutes.;The amino acid sequence of C.PRX is confirmed …
High Resolution Gas Phase Studies Of Inner-Shell Excitation And Decay, Zhifeng Liu
High Resolution Gas Phase Studies Of Inner-Shell Excitation And Decay, Zhifeng Liu
Digitized Theses
High resolution {dollar}L\sb{lcub}2,3{rcub}{dollar} x-ray absorption near-edge structure of P, S and Cl compounds are reported and analyzed with the aid of SW-X{dollar}\alpha{dollar} calculations. In the post-edge region, the outgoing channels are dominated by the d channels, and the post-edge features can be understood by the interactions between the d channels and the bonding environment, such as crystal-field splitting, and centrifugal potential. The pre-edge structures are found to be influenced by the d characters mixed into the unoccupied orbitals, which are again determined by the bonding environment.;High resolution photoelectron spectra are reported for the inner valence region of {dollar}N\sb2{dollar} and CO. …
Design And Implementation Of Expert Systems In Trace Metal Analysis, Sharbari Lahiri
Design And Implementation Of Expert Systems In Trace Metal Analysis, Sharbari Lahiri
Digitized Theses
Atomic Absorption Expert (AAexpert) is an expert system dealing with automated analysis for trace metals by atomic absorption spectrometry (AAS). This program consists of several stand-alone expert systems, each performing a specific task associated with the analysis.;In this thesis, the design and implementation of three important modules of AAexpert have been studied. These are (a) AAdiagnosis - detects problems associated with analytical data of poor quality and instrument malfunction, (b) AA-Quality Control (AA-QC) - provides a real-time assessment of the quality of measured absorbance values, and (c) AAmethods - selects a method of analysis from a method selection database and …
Rate And Equilibrium Constants Of Useful Reactions, Jinqiao Lu
Rate And Equilibrium Constants Of Useful Reactions, Jinqiao Lu
Digitized Theses
Part I. The halogenation of propiophenone has been reported to give rise to benzoic acid and acetic acid. It was discovered that under some conditions, the major product of the chlorination of propiophenone is 2-phenylglyceric acid, and that this appears to be a general reaction. 1-Phenyl-1,2-propanedione and 3-chloro-1-phenyl-1,2-propanedione have been proven to be the key intermediates on the chlorination path leading to 2-phenylglyceric acid. The migratory aptitudes of substituted methides ({dollar}\sp-{dollar}CH{dollar}\sb2{dollar}X) are also reported.;Part II. For the classical Michael reaction, the forward addition rate is second order overall, first order in the concentration of methyl cinnamate and first order in …
Aluminum, Silicon, Phosphorus And Sulfur K- And L-Edge X-Ray Absorption Spectroscopy Of Minerals And Glasses: Applications In Mineralogy And Geochemistry, Dien Li
Digitized Theses
Al, Si, P and S K- and L-edge X-ray absorption near-edge structure (XANES) spectra of a large selection of metal sulfide and silicate minerals and some glasses have been studied using monochromatized synchrotron radiation.;S K- and L-edge XANES spectra of metal sulfides are qualitatively interpreted based on MO/energy band models, reveal the DOS of unoccupied S s-, p- and d-like states, provide new insight into the electronic structure of the conduction band, and demonstrate the bonding interaction of metal d electrons with S 3s and 3p electrons. The S K- and L-edges shift to high energy with increase in oxidation …
Beta-Enolization In Bicyclic Ketones, David James Muir
Beta-Enolization In Bicyclic Ketones, David James Muir
Digitized Theses
A variety of bicyclic ketones was prepared and under strongly basic conditions (t-BuOK/t-BuOH/185{dollar}\sp\circ{dollar}C) their behaviour with respect to {dollar}\beta{dollar}-enolization was examined. Several new compounds were produced upon such treatment; these were identified on the basis of their {dollar}\rm\sp{lcub}13{rcub}Cmr{dollar} and {dollar}\rm\sp1Hmr{dollar} spectra.;3,3-Dimethylbicyclo (3.2.2) nonan-2-one slowly rearranged to 3,3-dimethylbicyclo (3.3.1) nonan-2-one, and the latter was stable. Similarly, 3,3-dimethylbicyclo (3.2.2) non-6-en-2-one rearranged to 3,3-dimethylbicyclo (3.3.1) non-6-en-2-one, which was not stable. Experiments with 3,3-dimethylbicyclo (3.3.1) non-6-en-2-one revealed that it was converted into five compounds. The major product, 2,2-dimethyl-4,5,6,7-tetra-hydrindan-1-one, arose from a {dollar}\beta{dollar}-enolate rearrangement. However, this enone underwent slow reduction to cis- and trans-8,8-dimethylbicyclo (4.3.0) …
Magnetic Circular Dichroism Spectroscopy Of Phthalocyanine Anions, John Douglas Mack
Magnetic Circular Dichroism Spectroscopy Of Phthalocyanine Anions, John Douglas Mack
Digitized Theses
An upgraded version of the program SIMPFIT is used to carry out deconvolution analyses on the uv-visible absorption and magnetic circular dichroism (MCD) spectra of zinc phthalocyanine, ZnPc({dollar}-{dollar}2), and the ring reduced anion radical of zinc phthalocyanine, (ZnPc({dollar}{lcub}-3{rcub})\rbrack\sp-.{dollar} A detailed study of the temperature dependence of the absorption and MCD spectra of ZnPc({dollar}-{dollar}2) shows that a significant fraction of the spectral intensity observed at room temperature can be assigned as 'hot' bands. This results in a significant discrepancy in the absorption and MCD band widths of the major transitions. Spectral band deconvolution was therefore carried out on data recorded at …
Transition Metal Rimmed Calixarenes And Their Supramolecular Chemistry, Wei Xu
Transition Metal Rimmed Calixarenes And Their Supramolecular Chemistry, Wei Xu
Digitized Theses
This thesis describes the design and the synthesis of novel anion and cation receptors in which sets of transition metal atoms are introduced on the rims of calixarene bowls.;A bowl-shaped calixresorcinarene 1 has been derivatized to incorporate either four phosphonite units to give a phosphonito-cavitand 2 or eight phosphinite units to give a phosphinito-calixresorcinarene 3. These derivatives have been used as multidentate ligands to incorporate transition metals on the upper-rim of the calixresorcinarene bowl. The chlorogold(I) complex of 4, 2(AuCl){dollar}\sb4{dollar} which was characterized by an X-ray structure determination, is shown to contain three AuCl units around the upper rim of …
The Photocatalytic Efficiency Of Titanium Dioxide Particles, Georg Riegel
The Photocatalytic Efficiency Of Titanium Dioxide Particles, Georg Riegel
Digitized Theses
Titanium dioxide particles in the anatase crystal form are more efficient in typical photocatalytic applications than are particles in the rutile crystal form. Furthermore, substantial variations in photocatalytic efficiency are generally found among different samples of anatase, as well as rutile particles. The aim of the present study was to identify the dominant cause of these variations. Since electrons at the conduction-band edge of anatase have a larger "driving force" in the reduction of dissolved {dollar}\rm O\sb2{dollar}, it was of particular interest to investigate if the dissimilar efficiencies found for particles of rutile and anatase are primarily due to differences …
The Behaviour Of Glycosphingolipids Under A Variety Of Structural And Environmental Influences, Dev Mitra Singh
The Behaviour Of Glycosphingolipids Under A Variety Of Structural And Environmental Influences, Dev Mitra Singh
Digitized Theses
The influence of naturally occurring glycosphingolipid (GSL) structural variations as modulators of glycolipid organization and dynamics was considered by wideline {dollar}\sp2{dollar}H-NMR in bilayer model membranes. Non-perturbing deuterium probes were placed at selected locations within polar and hydrophobic regions. A variety of environmental influences, which have been widely considered as major determinants of GSL function as recognition sites and structural elements, was examined.;GSL oligosaccharide orientation and motional order were monitored while systematically altering primary GSL structure changes and membrane environment. Each glycolipid, as a minor membrane component, demonstrated clear evidence of preferred average oligosaccharide orientation. Strikingly, the conformation and motional order …
Tetramesitylgermasilene: Synthesis And Reactivity Of A Germanium-Silicon Double Bond, Jeffrey A. Cooke
Tetramesitylgermasilene: Synthesis And Reactivity Of A Germanium-Silicon Double Bond, Jeffrey A. Cooke
Digitized Theses
This thesis describes the synthesis of tetramesitylgermasilene (Mesityl=2,4,6-trimethylphenyl), the first example of a compound containing a germanium-silicon double bond, from hexamesitylsiladigermirane, the first compound containing a three-membered ring composed of two germanium atoms and one silicon atom. The synthesis can be effected both thermochemically and photochemically; however, the germasilene can only be characterized in solution at {dollar}{lcub}-78{rcub}\sp\circ{dollar}C.;In addition, a remarkable 1,2-mesityl rearrangement of the germasilene to form a silylgermylene is reported, with discussion describing a similar rearrangement found in tetramesityldigermene, a compound containing a germanium-germanium double bond. Finally, the thesis details initial investigations into the reactivity of the germasilene with …
Oxidative Addition As A New Route To Organometallic Polymers And Dendrimers, Sudhir Achar
Oxidative Addition As A New Route To Organometallic Polymers And Dendrimers, Sudhir Achar
Digitized Theses
This thesis describes new routes to organometallic polymers and dendrimers employing an oxidative addition method. The new complexes {dollar}\lbrack\rm PtMe\sb2(NN)\rbrack{dollar} 1, (1b: (NN) = 4,4{dollar}\sp\prime{dollar}-di-tert-butyl-2,2{dollar}\sp\prime{dollar}-bipyridine; 1c: (NN) = 4,4{dollar}\sp\prime{dollar}-dimethyl-2,2{dollar}\sp\prime{dollar}-bipyridine; 1d: (NN) = 4-vinyl-4{dollar}\sp\prime{dollar}-methyl-2,2{dollar}\sp\prime{dollar}-bipyridine) were shown to be useful precursors to polymers. {dollar}\{lcub}{dollar}Note 1a: (NN)= 2,2{dollar}\sp\prime{dollar}-bipyridine{dollar}\{rcub}{dollar}.;The oxidative addition of organic halides (R-X) to 1 gave {dollar}\lbrack\rm PtXMe\sb2R(NN)\rbrack{dollar} {dollar}\rm\{lcub} (NN)\sb{lcub}1a{rcub}{dollar}: R-X = methyl 2-(bromomethyl)acrylate; 2-(bromomethyl)acrylic acid; 2-bromoethyl methacrylate; methyl bromoacetate; ethyl bromoacetate; bromoacetic acid; bromoacetonitrile and bromoacetamide. {dollar}\rm (NN)\sb{lcub}1b{rcub}{dollar}: (R-X) = 2-bromoethyl methacrylate and vinyl bromoacetate. {dollar}\rm (NN)\sb{lcub}1d{rcub}{dollar}: vinyl bromoacetate; 2-bromoethyl methacrylate; acryloyl chloride and vinylbenzyl chloride{dollar}\{rcub}{dollar}.;The free radical polymerization of the …
Charge Redistribution And Electronic Behaviour Of Gold-Coper Alloys: Bulk And Surface Studies, Markus Kuhn
Charge Redistribution And Electronic Behaviour Of Gold-Coper Alloys: Bulk And Surface Studies, Markus Kuhn
Digitized Theses
The electronic and physical properties of noble metals and their alloys have been the focus of research for many years. They are considered prototypes for the investigation of full d-band interactions and Friedel charge screening.;We have studied a series of bulk Au-Cu alloys, with varying compositions and ordering, in order to determine the nature and amount of charge transfer between the two components. We also examine the validity of two models; charge compensation and d-d repulsion. To probe the electronic behaviour upon alloying, we employ two techniques, namely photoemission and X-ray absorption. From photoemission, we find unique behaviour in the …
Repair Of Uv-Irradiated Plasmids In Escherichia Coli And Chinese Hamster Cells, Masood-Ur-Rehman Baig
Repair Of Uv-Irradiated Plasmids In Escherichia Coli And Chinese Hamster Cells, Masood-Ur-Rehman Baig
Digitized Theses
Nucleotide excision repair of DNA, demonstrated by the removal of cyclobutane pyrimidine dimers (CPDs), proceeds much more rapidly in genes undergoing transcription than in inactive genes and this rapid repair is confined to the strand being transcribed. The phenomenon is referred to as transcription-repair coupling and it has been demonstrated to occur in the chromosomes of mammalian cells, yeast cells and Escherichia coli. It was of interest to examine the repair characteristics of plasmids both in E. coli and Chinese hamster (CHO) cells.;Some of the findings obtained with the E. coli system were the following: The Rec A function is …
Ionic Conductivity Of Rubidium Chloride, Marcia Lee Vernon
Ionic Conductivity Of Rubidium Chloride, Marcia Lee Vernon
Digitized Theses
This investigation describes a theoretical and experimental examination of the defect properties of rubidium chloride. A theoretical study of the defect properties of RbBr and RbI is also presented.;Defect energy calculations were carried out on RbCl, RbBr and RbI using the HADES code and electron-gas potentials that were fitted to the crystal properties. Damping of the long-range dispersion energy was introduced during fitting of the potential and in the calculation of perfect lattice and defect properties.;In addition, defect energy calculations were done on Rb{dollar}\sb2{dollar}S using potentials developed for the RbCl:S{dollar}\sp{lcub}2-{rcub}{dollar} system. These calculations represent the first theoretical study of the …
Evidence For A Continuum Model Of Diffusion In Lipid Bilayer Membranes: Synthesis And Studies Of Macrocyclic Polyamides In Monolayer And Lipid Bilayer Systems, Patricia Alison Paprica
Evidence For A Continuum Model Of Diffusion In Lipid Bilayer Membranes: Synthesis And Studies Of Macrocyclic Polyamides In Monolayer And Lipid Bilayer Systems, Patricia Alison Paprica
Digitized Theses
This research project is directed towards establishing the relationship between the surface areas of intermediately sized molecules (50-300A{dollar}\sp2{dollar}) and their lateral diffusion coefficients in lipid bilayer membranes. Synthetic methods were developed to allow for the preparation of two series of macrocyclic polyamide amphiphiles, with and without fluorescent nitrobenzoxadiazole (NBD) labels, using macrocyclic polyamine aza-crown ethers as starting materials.;The geometry of the macrocyclic polyamides were determined using variable temperature NMR, which has indicated that both the C(O)-N bond and NBD-N bond in the smallest, labelled macrocyclic polyamide exhibit partial double bond character. As a consequence of this restricted bond rotation, both …
Role Of Colligin In Collagen Biosynthesis, Neeraj Jain
Role Of Colligin In Collagen Biosynthesis, Neeraj Jain
Digitized Theses
Colligin, a glycoprotein of molecular mass 46 kDa, is localized in the endoplasmic reticulum of diverse kinds of cells which produce collagen I. It binds collagen type I and type IV. As a step towards defining the role of colligin in the cell, the binding characteristics were studied in detail. Two different binding assays were developed. These studies showed that three moles of colligin bind per mole of procollagen with a K{dollar}\sb{lcub}\rm d{rcub}{dollar} of about 25 nM. In vivo cross-linking experiments revealed that colligin also binds to procollagen in the ER along with two other ER resident proteins, PDI and …
Adamantane-Like Clusters Of The Zinc-Group Elements, Yuyang Wu
Adamantane-Like Clusters Of The Zinc-Group Elements, Yuyang Wu
Digitized Theses
Three new types of chalcogenate-bridged adamantane-like clusters of the zinc-group elements have been studied in detail: those with alkylthiolates as bridging ligands, formulated as (({dollar}\mu{dollar}-{dollar}\rm SAlk)\sb6(MX)\sb4\rbrack\sp{lcub}2-{rcub}{dollar} (Alk = Me, Et, 1-Pr, 2-Pr, 1-Bu, 2-Bu, c-{dollar}\rm C\sb6H\sb{lcub}11{rcub}{dollar}(Cy), or CH{dollar}\sb2{dollar}Ph (Bz); M = Zn, Cd, or Hg; X = Cl, Br, or I); those with phosphines as terminal ligands, formulated as (({dollar}\mu{dollar}-ER){dollar}\sb6{dollar}(CdPPh{dollar}\sb3)\sb{lcub}4-n{rcub}{dollar}(Cd){dollar}\sb{lcub}n{rcub}\rbrack \sp{lcub}2+{rcub}{dollar} (E = S or Se; R = 1-Pr, 2-Pr, 1-{dollar}\rm C\sb5H\sb{lcub}11{rcub}{dollar} (1-Pe), Cy, or Ph; n = 0, 1, or 2); and those with halides as bridging ligands, formulated as (({dollar}\mu{dollar}-ER){dollar}\sb{lcub}6-m{rcub}(\mu{dollar}-X){dollar}\sb{lcub}m{rcub}{dollar}(MX){dollar}\sb4\rbrack\sp{lcub}2-{rcub}{dollar} (E = S or Se; R = Et, …
Mechanistic And Synthetic Investigations In Sulfonyl Chemistry And Acyl Transfer, Zhen Rong Guo
Mechanistic And Synthetic Investigations In Sulfonyl Chemistry And Acyl Transfer, Zhen Rong Guo
Digitized Theses
This thesis contains three chapters dealing with the organic chemistry of sulfonyl and carbonyl compounds. The first chapter describes the synthesis and rate studies of a series of {dollar}\beta{dollar}-methoxy sulfones and their unsubstituted parent compounds designed to test some basic ideas of the nature of the electronic effects of substituents in saturated systems. The substrates were designed to illustrate the effect of the change of the H{dollar}\sb\alpha{dollar}-C{dollar}\sb\alpha{dollar}-C{dollar}\sb\beta{dollar}-O dihedral angle on the rate of base-promoted H-D exchange reaction. The presence of a {dollar}\beta{dollar}-methoxy group affected the H-D exchange rates by factors varying from a few hundred to greater than ten thousands. …
Quantum Yields And Mechanism In Titanium Dioxide Mediated Photocatalysis, Lizhong Sun
Quantum Yields And Mechanism In Titanium Dioxide Mediated Photocatalysis, Lizhong Sun
Digitized Theses
The photocatalytic pathway in TiO{dollar}\sb2{dollar} suspensions was examined using a spin trap/EPR technique within a competition kinetic scheme. Experimental results from competition reactions indicate that there is a marked difference in kinetic behaviours between the systems with (heterogeneous) and without (homogeneous) a TiO{dollar}\sb2{dollar} suspension, which confirms that the reaction pathway of {dollar}\cdot{dollar}OH radicals in the TiO{dollar}\sb2{dollar} suspension is at least partly heterogeneous. A photocatalytic mechanism is proposed.;A method of determining the trapping efficiency of {dollar}\cdot{dollar}OH radicals was developed with the help of a spin trap/EPR method, using the spin trap 5,5-dimethyl-1-pyrroline N-oxide (DMPO), for the measurement of growth rates of …
Synthetic Applications Of The Photochemical Cycloaddition Reactions Of N-Acylindoles And Conformational Studies Of The Cycloadducts, Boke Zhang
Digitized Theses
The ability of a series of nitrogen-substituents to activate the cycloaddition photochemistry of indoles has been examined; the N-substituents were chosen in order to enable their removal following cycloaddition under mild neutral, acidic or basic conditions. N-substituted indoles, 17, 12 and 104c-g, were prepared in which the N-substituent is COPh, CO{dollar}\sb2{dollar}Et, CO{dollar}\sb2{dollar}CH{dollar}\sb2{dollar}CH{dollar}\sb2{dollar}SiMe{dollar}\sb3{dollar}, CO{dollar}\sb2{dollar}CH{dollar}\sb2{dollar}CH{dollar}\sb2{dollar}CN, CO{dollar}\sb2{dollar}Bu{dollar}\sp{lcub}\rm t{rcub}{dollar}, CO{dollar}\sb2{dollar}Ph, and CO{dollar}\sb2{dollar}CH{dollar}\sb2{dollar}Ph, respectively.;The silylethoxycarbonyl group of photoadducts derived from 104c can be removed by treatment of the adduct with fluoride ion in dichloromethane, the tert-butyloxycarbonyl group of adducts derived from 104e by treatment with trifluoroacetic acid at room temperature; the benzyloxycarbonyl group of adducts …
Ph Optimization Of Nucleophilic Reactions And Mechanisms Of Reactions Of Sulfonyl Chlorides, Joe Ying Lam
Ph Optimization Of Nucleophilic Reactions And Mechanisms Of Reactions Of Sulfonyl Chlorides, Joe Ying Lam
Digitized Theses
This thesis consists of four chapters all involving the chemistry of sulfonyl chlorides in water.;Chapter 1 describes the mechanisms of the reactions of alkanesulfonyl chlorides with water with and without added nucleophiles. Evidence is provided that the hydrolysis of alkanesulfonyl chlorides proceeds (a) at low pH, by S{dollar}\sb{lcub}\rm N{rcub}{dollar}2-S attack of water, (b) at intermediate pH, by rate determining attack of hydroxide anion to form sulfene which is then trapped by water, and (c) at high pH, by way of sulfene both formed and trapped by hydroxide anion. Among the following pathways observed in the reaction of alkanesulfonyl chlorides with …
Metal And Ring Oxidation In Metallophthalocyanines, Edward A. Ough
Metal And Ring Oxidation In Metallophthalocyanines, Edward A. Ough
Digitized Theses
Absorption and magnetic circular dichroism (MCD) spectra of neutral and oxidized magnesium and iron phthalocyanine (MgPc and FePc) are reported. Chemical, electrochemical and photochemical methods are employed in the generation of the stable {dollar}\pi{dollar}-cation radical of magnesium phthalocyanine. The broad absorption band at 500 nm is a "marker" band that verifies oxidation of the phthalocyanine ring. Variable temperature absorption and EPR spectra indicate that oxidized MgPc({dollar}-{dollar}1) exists in solution as a mixture of monomer ( (MgPc({dollar}-{dollar}1)) {dollar}\cdot\sp+{dollar})and dimer ( (MgPc({dollar}-{dollar}1)) {dollar}\sbsp{lcub}2{rcub}{lcub}++{rcub}{dollar}). Least squares and Simplex calculations were performed on the absorption and MCD spectra of MgPc({dollar}-{dollar}2) and MgPc({dollar}-{dollar}1) to determine …
Chemistry Of Binuclear And Cluster Complexes Of Ruthenium, Cobalt And Nickel, Hameed A. Mirza
Chemistry Of Binuclear And Cluster Complexes Of Ruthenium, Cobalt And Nickel, Hameed A. Mirza
Digitized Theses
The work described in this thesis is mainly focused on the synthesis, characterization and chemical reactivity of dinuclear and trinuclear phosphine substituted carbonyl complexes of Ru, Co and Ni. The thesis can be broadly classified into three sections. The first section comprising chapters 2 and 3, deals with the chemistry of dinuclear and trinuclear ruthenium complexes with dppm, bis(diphenylphosphino)methane, bridging ligands. The reaction mixture RuCl{dollar}\sb3{dollar}/dppm/NaBH{dollar}\sb4{dollar}/CO yielded mainly trans- (RuCl{dollar}\sb2{dollar}(dppm){dollar}\sb2{dollar}). However, when silver acetate was added to the reaction mixture prior to the reduction with NaBH{dollar}\sb4{dollar}, a high yield synthesis of (Ru{dollar}\sb2{dollar}({dollar}\mu{dollar}-CO)(CO){dollar}\sb4{dollar}({dollar}\mu{dollar}-dppm){dollar}\sb2{dollar}) was achieved. In addition, (RuH(CO)(dppm){dollar}\sb2{dollar}) {dollar}\sp+{dollar} and the electron …
Decay Of The Triplet State In A Porphyrin Quinone Molecule, David Donald Fraser
Decay Of The Triplet State In A Porphyrin Quinone Molecule, David Donald Fraser
Digitized Theses
Workers in this and many other labs have been studying photoinduced electron transfer seeking to understand the photochemical processes in photosynthesis. Closely related processes also constitute the basis of some photosensitive tissue diseases and of a wide variety of industrial applications. To study the photophysics unhindered by diffusion, a molecule composed of a freebase porphyrin covalently linked to a p-benzoquinone by an amide linkage was used.;A nanosecond laser flash photolysis apparatus permitted the observation of the porphyrin triplet state decay, with the quinone fully reduced or with it fully oxidized to allow enhanced quenching of the porphyrin triplet via electron …
Aspects Of Pulmonary Surfactant Metabolism, Rudolf A. Veldhuizen
Aspects Of Pulmonary Surfactant Metabolism, Rudolf A. Veldhuizen
Digitized Theses
Pulmonary surfactant stabilizes the lung by reducing the surface tension at the air liquid interface of the alveolus. Phosphatidylcholine represents the principal component of surfactant (70% by weight), other lipids account for 20% of surfactant and the remaining 10% is protein. Four surfactant-associated proteins have been identified, surfactant associated protein (SP) SP-A, SP-B, SP-C and SP-D.;This thesis describes the investigations on the following aspects of surfactant metabolism: (1) phosphatidylcholine synthesis, (2) alterations in surfactant after lung transplantation and (3) mechanisms of alveolar surfactant subtype conversion.;(1) The de novo synthesis of acyl-specific phosphatidylcholine via the acylation of glycerol-3-phosphocholine (GPC) has been …
High-Resolution Photoelectron Spectroscopy Using Synchrotron Radiation: Ligand Field And Vibrational Splitting And Chemical Effects On Linewidths, Jeffrey N. Cutler
High-Resolution Photoelectron Spectroscopy Using Synchrotron Radiation: Ligand Field And Vibrational Splitting And Chemical Effects On Linewidths, Jeffrey N. Cutler
Digitized Theses
High resolution photoelectron spectra of numerous Group IV, VII and VIII compounds have been recorded using a newly constructed photoelectron spectrometer based on the McPherson ESCA 36 hemispherical analyzer. This spectrometer is designed to make use of the high electron resolution and transmission of the analyzer coupled with the tunability and high photon resolution which is inherent in synchrotron radiation.;For the first time using this instrument, it has become possible to differentiate between three distinct core level broadening mechanisms: vibrational and ligand field splitting and a chemical effect on linewidths. Several I 4d photoelectron spectra of seven different iodine-containing compounds …
Studies Of The Behaviour Of Lipophilic Molecules In Model Membranes: Applications To Amphotericin B And Glycosphingolipids, Katherine S. Hamilton
Studies Of The Behaviour Of Lipophilic Molecules In Model Membranes: Applications To Amphotericin B And Glycosphingolipids, Katherine S. Hamilton
Digitized Theses
Our investigations have focused on two model membrane systems: liposomal amphotericin B and glycosphingolipids as minor components in phospholipid bilayers. Although amphotericin B and glycosphingolipids have very diverse biological functions, studying their respective behaviour and interactions in the context of a lipid bilayer is of prime importance.;The association of amphotericin B with lipid vesicles has proven to be a successful modality of treatment, with an antifungal activity that is closely tied to the physical nature (e.g. vesicle size and lipid composition) of the preparation. Using freeze-fracture electron microscopy, density gradient ultracentrifugation, and differential scanning calorimetry we have characterised the basic …
Genomic Characterization Of Steroid Hormone-Binding Globulins, D Alan Underhill
Genomic Characterization Of Steroid Hormone-Binding Globulins, D Alan Underhill
Digitized Theses
Sex-hormone binding globulin (SHBG) and corticosteroid binding globulin (CBG) are the major plasma transport proteins for sex-steroids and glucocorticoids, respectively, and may impact directly upon steroid hormone bioavailability to target cells. Androgen binding protein (ABP) is closely related to SHBG and is believed to maintain an androgenic environment for sperm maturation. The isolation of SHBG-related cDNAs from human testis and a corresponding transcription unit indicates that SHBG and ABP are encoded by the same gene. In addition, the SHBG/ABP gene gives rise to two novel testicular transcripts through a process of alternative splicing. The putative proteins encoded by these transcripts …
In Search Of An Alternative Route To Germasilenes: The Synthesis And Chemistry Of (Halosilyl)Germanes, Umesh Ramji Parshotam
In Search Of An Alternative Route To Germasilenes: The Synthesis And Chemistry Of (Halosilyl)Germanes, Umesh Ramji Parshotam
Digitized Theses
This thesis describes attempts to prepare a germasilene, a compound containing a germanium-silicon double bond, by either a {dollar}\beta{dollar}-elimination reaction or a reductive elimination reaction.;The precursor, Mes{dollar}\sb2{dollar}HGeSiClMes{dollar}\sb2{dollar}, 1, (Mes = 2,4,6-trimethylphenyl) was prepared by the addition of Mes{dollar}\sb2{dollar}HGeLi to Mes{dollar}\sb2{dollar}SiCl{dollar}\sb2{dollar} in THF in excellent yield. We examined the effect of changing the nature of the solvent, leaving group, base and ligands on the reaction between 1 and base.;Mes{dollar}\sb2{dollar}ClGeSiClMes{dollar}\sb2,{dollar} 29, and Mes{dollar}\sb2{dollar}BrGeSiClMes{dollar}\sb2{dollar}, 30, prepared by the chlorination and bromination of 1 respectively, were treated with lithium naphthalenide (LiNp) in an attempt to prepare Mes{dollar}\sb2{dollar}Ge = SiMes{dollar}\sb2{dollar} by a reductive elimination reaction. …