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Genome Organization, Replication, And Defective Rnas Of Clover Yellow Mosaic Virus, Karl Andrew White
Genome Organization, Replication, And Defective Rnas Of Clover Yellow Mosaic Virus, Karl Andrew White
Digitized Theses
The potexvirus clover yellow mosaic virus (CYMV) is a 540 nm long flexible rod-shaped virus which contains as its genetic material a messenger-sense single-stranded RNA. We have cloned a cDNA to the genomic RNA (gRNA) of CYMV and, through collaboration, have determined its entire nucleotide sequence. The 7015 nucleotide gRNA encodes five major open reading frames (ORFs) which are arranged in a similar manner to those in other potexvirus gRNAs. A variety of in vitro and in vivo techniques were used to examine how viral proteins encoded by CYMV are expressed. Expression of ORFs encoded 3{dollar}\sp\prime{dollar} in the gRNA appear …
Analysis Of Rat And Humancdnas Encoding Colligin, A Collagen-Binding Protein, Elke Petra Clarke
Analysis Of Rat And Humancdnas Encoding Colligin, A Collagen-Binding Protein, Elke Petra Clarke
Digitized Theses
Several cDNA clones for both human and rat colligin, a collagen-binding protein, were isolated from human skin fibroblasts and rat skeletal myoblasts. The full-length cDNAs for both human and rat colligin encoded a 17-amino acid signal peptide and a 400-amino acid mature protein containing several potential N-linked oligosaccharide binding sites and a COOH-terminal RDEL sequence. This COOH-terminal tetrapeptide has been shown to act as an endoplasmic reticulum retention sequence in other systems. The derived amino acid sequence of human colligin shows 98.6% identity with rat colligin (previously called "gp46" from L6 myoblasts), 80% identity with hsp47 from chick embryo fibroblasts, …
Oxidative Addition Reactions Of Dimethylplatinum(Ii) Complexes, Khin Than Aye
Oxidative Addition Reactions Of Dimethylplatinum(Ii) Complexes, Khin Than Aye
Digitized Theses
This work deals with synthesis, characterization and reaction mechanisms in studies of the oxidative addition of organic compounds to dimethyl(1,10-phenanthroline)-platinum(II), (PtMe{dollar}\sb2{dollar}(NN)). The organic compounds studied include lactones, epoxides, alkylpalladium(IV) complexes, alkyl halides including a coumarin derivative, and diphenyl diselenide and diphenyl disulphide. A particularly detailed study has been made of the oxidative addition of the C-O bonds of a {dollar}\beta{dollar}-lactone and of epoxides.;The oxidative addition of propiolactone to the platinum(II) complex to give a platina(IV)lactone, (PtMe{dollar}\sb2\{lcub}{dollar}CH{dollar}\sb2{dollar}CH{dollar}\sb2{dollar}C(O)O{dollar}\{rcub}{dollar} (NN)), (NN = 2,2{dollar}\sp\prime{dollar}-bipyridine or 1,10-phenanthroline) is reported. The structure is determined by both NMR and X-ray crystallography. The oxidative addition of propiolactone to …
Studies In Organic Synthesis: I Demethylation Of Methyl Enol Ethers And Methyl Aryl Ethers Ii Toward Sexiphenylene Iii Toward A New Method For Vinylcyclopropanation, Jeffrey Robert Walker
Studies In Organic Synthesis: I Demethylation Of Methyl Enol Ethers And Methyl Aryl Ethers Ii Toward Sexiphenylene Iii Toward A New Method For Vinylcyclopropanation, Jeffrey Robert Walker
Digitized Theses
Cycloseychellene, a tetracyclic sesquiterpene, has been a synthetic target of our group for some time and earlier work had ended with the preparation of a methyl enol ether intermediate. A possible pathway for the completion of this total synthesis had, as its key step, an intramolecular Prins (ene) reaction. Studies were conducted in order to examine possible methods for the formation of the enolate which this approach required. The possible use of a silyl enol ether, as the enolate precursor, was examined in a model study, but the preparation of the enol ether was not successful. In addition, model studies …
Biosynthesis And Metabolism Of Dolichol And Polyprenol In The Seeds And Seedlings Of Rye (Secale Cereale L), Robert Thomas Rymerson
Biosynthesis And Metabolism Of Dolichol And Polyprenol In The Seeds And Seedlings Of Rye (Secale Cereale L), Robert Thomas Rymerson
Digitized Theses
The seeds of monocotyledonous plants contain both dolichol, an homologous series of {dollar}\alpha{dollar}-saturated polyisoprenoid alcohols, and polyprenol, and homologous series of {dollar}\alpha{dollar}-unsaturated polyisoprenoid alcohols. Dolichyl phosphate (Dol-P) participates in the N-glycosylation of proteins. The function of polyprenol is unknown. Several possible roles for polyprenol were investigated in rye (Secale cereale L.). Methods for the extraction, separation, analysis, and quantification of polyisoprenoids were developed. Rye embryos contained twice as much polyprenol as dolichol; the ratio of polyprenyl phosphate to dolichyl phosphate was estimated at three to one.;Experiments on the metabolic labelling of polyisoprenoids with ({dollar}\sp3{dollar}H) H{dollar}\sb2{dollar}O, H{dollar}\sb3\lbrack\sp{lcub}32{rcub}{dollar}P) PO{dollar}\sb4{dollar}, or ({dollar}\sp{lcub}14{rcub}{dollar}C) mevalonolactone …
Intermolecular And Intramolecular Photocycloaddition Reactions Of Cyclopentenone And N-Acylindoles, David L. Oldroyd
Intermolecular And Intramolecular Photocycloaddition Reactions Of Cyclopentenone And N-Acylindoles, David L. Oldroyd
Digitized Theses
Aspects of the photochemistry of N-acylindoles in which the indole nitrogen is part of an amide or urethane group have been studied. It has been found that the chemical fate of the N-acylindole excited state can be controlled by appropriate choice of wavelength, solvent, concentration, excited state multiplicity and structure of the acyl substituent.;Irradiation of N-benzoylindole or N-ethoxycarbonylindole with ultra-violet light in the presence of cyclopentene gives a mixture of (2+2) cycloadducts and rearranged photo-Fries products. The quantum yields of formation of the photo-Fries products were found to be wavelength dependent and, especially in the case of N-benzoylindole, highly solvent …
Thermal Diffusion In Electrolyte Solutions, Hui Lu
Thermal Diffusion In Electrolyte Solutions, Hui Lu
Digitized Theses
1. A conductimetric technique has been used to study the thermal diffusion of dilute aqueous solutions of Me{dollar}\sb4{dollar}NBr, Me{dollar}\sb4{dollar}NIi, Et{dollar}\sb4{dollar}NBr, Et{dollar}\sb4{dollar}NI, Pr{dollar}\sb4{dollar}NBr, Pr{dollar}\sb4{dollar}NI, Pr{dollar}\sb4{dollar}NOH, Bu{dollar}\sb4{dollar}NCl, Bu{dollar}\sb4{dollar}NBr, Bu{dollar}\sb4{dollar}NI, Bu{dollar}\sb4{dollar}NSCN, Bu{dollar}\sb4{dollar}PCl, NaPh{dollar}\sb4{dollar}B, Ph{dollar}\sb4{dollar}PCl and Ph{dollar}\sb4{dollar}AsCl (Me = methyl, Et ethyl, Pr = propyl, Bu = butyl, Ph = phenyl). The enthalpies of transport of these salts, {dollar}H\sp*{dollar}, have unusual concentration dependences. For Me{dollar}\sb4{dollar}NBr and Me{dollar}\sb4{dollar}NI, {dollar}H\sp*{dollar} is almost constant. For the tetrabutylammonium salts, {dollar}H\sp*{dollar} passes through minima at high dilutions. {dollar}H\sp*{dollar} increases with concentration for the rest of salts. Only for Pr{dollar}\sb4{dollar}NOH does {dollar}H\sp*{dollar} decrease with concentration, which is the normal concentration …
Part I Photochemical Deconjugation Reactions Of 3-Alkyl-2-Cyclohexenones Part Ii Biradicals In 2+2 Photocycloaddition Reactions Of 2-Cyclopentenone, Andreas Rudolph
Part I Photochemical Deconjugation Reactions Of 3-Alkyl-2-Cyclohexenones Part Ii Biradicals In 2+2 Photocycloaddition Reactions Of 2-Cyclopentenone, Andreas Rudolph
Digitized Theses
Part I. Ultraviolet irradiation of 3-methyl-2-cyclohexenones leads to the formation of the deconjugated exocyclic isomers in low quantum yields. The reaction proceeds via the triplet excited state of the enone but the mechanism has not been determined satisfactorily. Part I of this thesis describes evidence for acid catalysis of the reaction. The presence of small quantities of carboxylic acid greatly enhances the quantum yield of the deconjugation reaction. The proposal of the intermediacy of a carbocation was supported by the detection of products derived from addition to the conjugate base of the acid to the carbocation. In addition, the presence …
Characterization And Localization Of A Novel Membrane Skeletal Protein, Louise Madeleine Desjardins
Characterization And Localization Of A Novel Membrane Skeletal Protein, Louise Madeleine Desjardins
Digitized Theses
The mechanism of skeletal myoblast differentiation has been of great interest to several laboratories for years. Cell-substratum adhesion and cell-cell recognition are two early steps in the development of fusion competence which is brought about by a family of cell surface proteins known as integrins. It is generally accepted that extracellular matrix-receptor complexes convey regulatory signals to the nucleus through interactions with cytoskeletal or membrane skeletal proteins. Therefore, it is important to study those membrane skeletal proteins which interact with cell surface proteins.;The approach was to raise monoclonal antibodies against L6 myoblasts and screen for those antibodies which were against …
Identification And Analysis Of A Genetic Locus, Tblvi-1, Frequently Disrupted By Retroviral Integration In Murine Thymic Lymphomas, Rosemary Ellen Mueller
Identification And Analysis Of A Genetic Locus, Tblvi-1, Frequently Disrupted By Retroviral Integration In Murine Thymic Lymphomas, Rosemary Ellen Mueller
Digitized Theses
Analysis of DNA from retrovirally induced tumours has revealed that the host sequences disrupted by retroviral integration in multiple independent tumours are "tagged" as genes critical to normal cell proliferation and differentiation. During retroviral infection, retroviral integration occurs randomly into many sites in the host genome. However retrovirally induced tumours can be shown to have originated from a single cell which has sustained genetic damage to particular cell sequences. Damage to these cell sequences has contributed to the development of this clone of cells into a tumour. Genes identified in this way are invaluable to the understanding of neoplastic as …
Gas Phase And Surface Reactions In Organometallic Chemical Vapour Deposition Of Platinum, Eric Chuan-Whatt Ou
Gas Phase And Surface Reactions In Organometallic Chemical Vapour Deposition Of Platinum, Eric Chuan-Whatt Ou
Digitized Theses
Organometallic chemical vapour deposition (OMCVD) films usually have carbon as an impurity. This comes from the decomposition of the ligands in the organometallic precursor. Understanding the chemical reactions in the decomposition will greatly enhance our ability to control the impurity level in these films and also the epitaxial growth of the films. Depending on the pressure in the reactor, the important reactions could be in the gas phase or on the surface.;Decomposition of the precursor, cis-dimethyl platinum diisocyanide in presence of hydrogen shows reduction in carbon impurity. The decomposition was carried out in an infrared gas cell so that infrared …
Interactions Of Oxygen With Zirconium(0001), Bernard Jerome Flinn
Interactions Of Oxygen With Zirconium(0001), Bernard Jerome Flinn
Digitized Theses
Interactions of oxygen with Zr(0001) have been studied using low energy electron diffraction (LEED), work function ({dollar}\Delta\phi{dollar}), static and dynamic secondary ion mass spectrometry (SSIMS, DSIMS), thermal desorption spectroscopy (TDS), Auger electron spectroscopy (AES) and nuclear reaction analysis (NRA).;The initial sticking coefficient of oxygen is close to unity up to {dollar}\sim{dollar}0.75 ML at 90, 293 and 473 K. Oxygen chemisorption is disordered at room temperature and below, with some oxygen locating in on-top sites and some subsurface. Heating the disordered surface to {dollar}\sim{dollar}473 K causes all oxygen to move to subsurface sites and a (1 x 2) ordered oxygen underlayer …
Mecanisme D'Action Des Sulfonates De Calcium Hyperbasiques En Regime De Lubrification Limite, Suzanne Giasson
Mecanisme D'Action Des Sulfonates De Calcium Hyperbasiques En Regime De Lubrification Limite, Suzanne Giasson
Digitized Theses
The formation mechanism of boundary film obtained with the overbased calcium sulfonates was investigated.;Firstly a physico-chemical analysis of the overbased calcium sulfonates was achieved. The structure, the size and the polydispersity of the micelles formed by the additive in oil, and the nature of the interactions existing between them were studied using Small Angle X-Ray Scattering (SAXS). Different parameters which can influence the micellar structure such as pressure, temperature and water, were also studied.;Secondly, the formation of the boundary film was studied using an alternating tribometer. The Infrared Reflexion Absorption Spectroscopy by Polarization Modulation (PM IRRAS), the Scanning Electron Microscopy …
Bioreductive Alkylating Agents As Probes For Tissue Hypoxia, Paul A. Culbert
Bioreductive Alkylating Agents As Probes For Tissue Hypoxia, Paul A. Culbert
Digitized Theses
The research discussed in the following thesis falls under the general categories of organic chemistry and radiochemistry and the application of these disciplines to the development of imaging agents and labelling techniques for the branch of Nuclear Medicine involving single photon emitting radionuclides. The thesis is made up of three sections; one dealing with the synthesis, labelling and biological testing of a series of radioiodinated 2-nitrobenzyl alcohol derivatives as potential probes for tissue hypoxia; a second chapter dealing with the synthesis, labelling and biological testing of 1-(4- ({dollar}\sp{lcub}123{rcub}{dollar}I) -iodophenyl-2,6,7-trioxabicyclo- (2.2.2) octane as a potential imaging agent for the GABA{dollar}\sb{lcub}\rm A{rcub}{dollar} …
Studies Of The Interactions Of Oxygen And Water With Aluminum(100), Stephen James Bushby
Studies Of The Interactions Of Oxygen And Water With Aluminum(100), Stephen James Bushby
Digitized Theses
The interactions of O{dollar}\sb2{dollar} and water with Al(100) have been studied by Nuclear Reaction Analysis (NRA), Thermal Desorption Spectroscopy (TDS), measurement of the work function ({dollar}\Delta\phi{dollar}), Photoelectron Spectroscopy (PES) and Fourier Transform InfraRed-Reflection Absorption Spectroscopy (FTIR-RAS). The major findings of this study are: The {dollar}\sp{lcub}18{rcub}{dollar}O(p,{dollar}\alpha)\sp{lcub}15{rcub}{dollar}N nuclear reaction is a useful alternative for determining absolute oxygen coverages by NRA. The absolute coverage of oxygen on Ni(100) at 300 K as a function of {dollar}\sp{lcub}18{rcub}{dollar}O{dollar}\sb2{dollar} exposure has been measured; the coverage of 2.45 {dollar}\pm{dollar} 0.10 ML (1 monolayer (ML) on Ni(100) = 1.61 {dollar}\times{dollar} 10{dollar}\sp{lcub}15{rcub}{dollar} particles cm{dollar}\sp{lcub}-2{rcub}{dollar}) at saturation corresponds to 3-3.4 …