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Au Yuen-yee. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 140-152). / Abstracts in English and Chinese. / Abstract --- p.iii / Acknowledgements --- p.v / Chapter Chapter One: --- General Background and Introduction --- p.1 / Chapter 1 -1 --- Introduction --- p.1 / Chapter 1-2 --- Three-Bond Coupling Constants (3J) --- p.1 / Chapter 1-2-1 --- Development of the Karplus Equation --- p.1 / Chapter 1-2-2 --- Application of3J in the Conformational Analysis of Nucleic Acid --- p.4 / Chapter 1-2-3 --- Problem of Accuracy for3 J Measurement --- p.7 / Chapter 1-3 --- Two-Bond Coupling Constants (2J) --- p.7 / Chapter 1-3-1 --- The Use of the Projection Method --- p.7 / Chapter 1-3-2 --- 2J Coupling Constant Involving Hydrogen Bonds --- p.8 / Chapter 1-4 --- One-Bond Coupling Constants (1J) --- p.10 / Chapter 1-5 --- Conclusion --- p.11 / Chapter Chapter Two: --- Experimental Section / Chapter 2-1 --- Introduction --- p.12 / Chapter 2-2 --- Heteronuclear Multiple-Quantum Coherence (HMQC) Experiment --- p.12 / Chapter 2-3 --- Experimental Section --- p.15 / Chapter 2-3-1 --- Sample Preparation --- p.15 / Chapter 2-3-2 --- NMR Spectroscopy --- p.16 / Chapter Chapter Three: --- Theory of Nuclear Spin-Spin Coupling Constants --- p.18 / Chapter 3-1 --- Introduction --- p.18 / Chapter 3-2 --- Application of Finite Perturbation Theory on Nuclear Spin-Spin Coupling --- p.18 / Chapter 3-3 --- Methodology --- p.22 / Chapter Chapter Four: --- DFT and NMR Study of1JCH Coupling Constants --- p.28 / Chapter 4-1 --- Introduction --- p.28 / Chapter 4-2 --- Nomenclature and Definition of Structural Parametersin DNA and RNA --- p.28 / Chapter 4-2-1 --- "Nomenclature, Symbols and Atomic Numbering Schemes" --- p.28 / Chapter 4-2-2 --- Definition of Torsion Angles and their Rangesin Nucleotides --- p.31 / Chapter 4-2-3 --- Description of the Furanose Ring --- p.31 / Chapter 4-3 --- Results and Discussion --- p.37 / Chapter 4-3-1 --- Basis Set Effect --- p.37 / Chapter 4-3-2 --- Relative Conformational Energy Profiles --- p.37 / Chapter 4-3-3 --- Comparison of the Dependence of 1JCH Coupling Constants on Conformational Changes With and Without the DNA Backbone --- p.40 / Chapter 4-3-4 --- Effect of Backbone 3'- and 5'-Phosphate --- p.42 / Chapter 4-3-5 --- Effect of Glycosidic Torsion Anglex --- p.49 / Chapter 4-3-6 --- Effect of Ring Conformation with Fixed Glycosidic Torsion Anglex --- p.52 / Chapter 4-3-7 --- Effect of Torsion Angle α --- p.52 / Chapter 4-3-8 --- Effect of Torsion Angle β --- p.53 / Chapter 4-3-9 --- Effect of Torsion Angle γ --- p.56 / Chapter 4-3-10 --- Effect of Torsion Angle ε --- p.59 / Chapter 4-3-11 --- Effect of Torsion Angle ζ --- p.61 / Chapter 4-3-12 --- Effect of Base Pairing --- p.65 / Chapter 4-3-13 --- Effect of Base Stacking from the (n-1) and (n+1) Base --- p.65 / Chapter 4-3-14 --- Comparison of Experimental and Theoretical Data --- p.68 / Chapter 4-4 --- Conclusion --- p.74 / Chapter Chapter Five: --- DFT Study of 2JCH and 3JCH Coupling Constants --- p.79 / Chapter 5-1 --- Introduction --- p.79 / Chapter 5-2 --- Results and Discussion on 2JCH Coupling Constants --- p.79 / Chapter 5-2-1 --- Effect of Backbone 3'- and 5'-Phosphate --- p.79 / Chapter 5-2-2 --- Effect of Ring Conformation with Fixed Glycosidic Torsion Anglex --- p.82 / Chapter 5-2-3 --- Effect of Glycosidic Torsion Anglex --- p.87 / Chapter 5-2-4 --- Effect of Torsion Angleγ --- p.87 / Chapter 5-2-5 --- Effect of Torsion Angle ε --- p.90 / Chapter 5-2-6 --- Effect of Base Pairing --- p.90 / Chapter 5-2-7 --- Effect of Base Stacking from the (n-1) and (n+1) Base --- p.90 / Chapter 5-3 --- Results and Discussion on 3JCH Coupling Constants --- p.95 / Chapter 5-3-1 --- Effect of Backbone 3'- and 5'-Phosphate --- p.95 / Chapter 5-3-2 --- Effect of Ring Conformation with Fixed Glycosidic Torsion Anglex --- p.95 / Chapter 5-3-3 --- "Effect of Different Torsion Angles (X,α,β,γ,ε,and ζ)" --- p.100 / Chapter 5-3-4 --- Effect of Base Pairing --- p.100 / Chapter 5-3-5 --- Effect of Base Stacking from the (n-1) and (n+1) Base --- p.105 / Chapter 5-4 --- Conclusion --- p.105 / Chapter Chapter Six: --- Conclusion --- p.111 / Appendix A Product Operator Formalism on HMQC Pulse Scheme --- p.113 / Appendix B Finite Perturbation Theory --- p.115 / Appendix C Supplementary Figures of Chapter Four --- p.118 / Appendix D Some of the NMR Spectra --- p.134 / References --- p.140

Previous studies have reported altered glutamate (Glu) concentrations in the blood and brain of individuals with autism spectrum disorder (ASD) compared to neurotypical controls (NC), but the direction (increased or decreased) of metabolite differences is still unclear. Moreover, the relationship between Glu and both brain function and clinical manifestations of the disorder require further investigation. Within this study, we investigated metabolite concentrations within the dorsal anterior cingulate cortex (dACC), a brain region functionally associated with inhibitory executive control tasks and also part of the salience network. There were 19 participants with ASD and 20 NCs between the ages of 23 and 58 years who participated in this study. A study clinician administered the Autism Diagnostic Observation Schedule (ADOS) to individuals with ASD to further confirm their diagnosis. In addition, all participants in this study completed assessments of general intelligence and attention, which included an inhibitory executive control task. Researchers also acquired in vivo single-voxel proton magnetic resonance spectroscopy (1H-MRS) in the dACC to quantify both Glu and combined Glu and glutamine (Glx) concentrations. We hypothesised that these metabolite concentrations would be altered (decreased or increased) in adult participants with ASD compared to NCs and would correlate with inhibitory performance and ASD severity in individuals with ASD. Participants also underwent a resting-state functional magnetic resonance imaging (fMRI) scan to assess the relationship between functional connectivity and Glu and Glx concentrations. We also hypothesised that there would be an altered relationship between local Glu and Glx concentrations and seed-based functional connectivity in adults with ASD compared to NCs. There were no significant group differences in Glu or Glx concentrations between individuals with ASD and NCs. Furthermore, we did not find any relationship between metabolite concentrations and either inhibitory performance or clinical symptoms of the disorder. This evidence suggests that increased or decreased Glu and Glx concentrations were not a core marker of altered brain function in the dACC in this group of adult individuals with ASD. When individuals taking psychotropic medications were excluded from the analysis, there was a significant interaction between age and group for Glx concentrations. This evidence weakly suggests disease-specific variations in Glx concentrations over the lifespan of an individual with ASD. Nevertheless, this result did not survive correction for multiple comparisons and requires further replication. In our final experiment, we reported that Glu concentrations were negatively correlated with right and left dACC seed-based resting-state functional connectivity to the left medial temporal lobe only in individuals with ASD. We also reported an interaction between groups in the association between Glx concentrations and both left and right dACC functional connectivity to other salience network regions including the insular cortex. This evidence suggests that local Glu and Glx concentrations were incongruent with long-distance functional connectivity in individuals with ASD. This analysis was largely exploratory, but further investigation and replication of these relationships may further explain the pathophysiology of the disorder as well as provide a useful marker for therapeutic intervention.

Lai, Kin Fung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 92-97). / Abstracts in English and Chinese. / Title Page --- p.i / Thesis Committee --- p.ii / Abstract (In English) --- p.iv / Abstract (In Chinese) --- p.v / Acknowledgement --- p.vi / List of Figures --- p.xii / List of Tables --- p.xiv / List of Symbols and Abbreviations --- p.xvi / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Chemical Shift Predictions of Nucleic Acids --- p.1 / Chapter 1.1.1 --- Chemical Shift --- p.1 / Chapter 1.1.2 --- Chemical Shift Prediction of Double Helical DNA and RNA --- p.1 / Chapter 1.1.3 --- Chemical Shift Prediction of Random Coil DNA --- p.2 / Chapter 1.1.4 --- Applications of Nucleic Acid Chemical Shift Prediction --- p.4 / Chapter 1.2 --- General Review of DNA Structure --- p.4 / Chapter 1.2.1 --- Structure and Nomenclature of Nucleotide --- p.4 / Chapter 1.2.2 --- Structure of Polynucleotide --- p.5 / Chapter 1.2.3 --- Sugar Conformation in Nucleotide --- p.5 / Chapter 1.2.4 --- Double Helical DNA Conformation --- p.7 / Chapter 1.3 --- A.A Mismatches in DNA Duplexes --- p.8 / Chapter 1.3.1 --- Mismatches in DNA Duplexes --- p.8 / Chapter 1.3.2 --- Biological Significance of A． A Mismatches --- p.9 / Chapter 1.4 --- Purpose of the Work --- p.9 / Chapter 2 --- Materials and Method --- p.10 / Chapter 2.1 --- Overview of the Proposed Prediction Method --- p.10 / Chapter 2.1.1 --- Nearest Neighbor Model --- p.10 / Chapter 2.1.2 --- Base Pair Replacement Approach --- p.10 / Chapter 2.2 --- Sample Design --- p.11 / Chapter 2.2.1 --- Reference Sequences for Obtaining Triplet Values and Correction Factors --- p.11 / Chapter 2.2.2 --- Sequences for Verifying the Base Pair Replacement Approach --- p.12 / Chapter 2.2.3 --- Sequences for Testing Chemical Shift Prediction Accuracy --- p.12 / Chapter 2.3 --- Sample Preparation --- p.13 / Chapter 2.4 --- NMR Experiments --- p.14 / Chapter 2.4.1 --- Non-labile Proton Resonance Assignment --- p.14 / Chapter 2.4.2 --- Labile Proton Resonance Assignment --- p.16 / Chapter 2.5 --- Validating the Assumption in Reference Hairpin Model Samples --- p.17 / Chapter 3 --- Establishment of Proton Chemical Shift Prediction method of A.A Mismatches in B-DNA Duplexes --- p.18 / Chapter 3.1 --- Resonance Assignment --- p.18 / Chapter 3.1.1 --- Non-labile Protons --- p.18 / Chapter 3.1.2 --- Labile Protons --- p.20 / Chapter 3.2 --- Validating the Assumption in Reference Hairpin Model Samples --- p.21 / Chapter 3.3 --- Extraction of A.A Mismatch Triplet Chemical Shift Values --- p.22 / Chapter 3.4 --- Calculation of the 5´ة- and 3´ة-Correction Factors --- p.24 / Chapter 3.5 --- Chemical Shift Prediction Using Triplet Values and Correction Factors Extracted from Top Strands of refA.A(XAY) and refA．T(XAY) --- p.27 / Chapter 3.6 --- Chemical Shift Prediction Using Triplet Values and Correction Factors Extracted from Bottom Strands of refA.A(XAY) and refA．T(XAY) --- p.28 / Chapter 4 --- Testing of Proton Chemical Shift Prediction of A.A Mismatches in B- DNA --- p.29 / Chapter 4.1 --- Prediction Result Using Triplet Values and Correction Factors Extracted from the Top Strands of refA.A(XAY) and refA.T(XAY) --- p.29 / Chapter 4.2 --- Prediction Result Using Triplet Values and Correction Factors Extracted from Bottom Strands of refA.A(XAY) and refAT(XAY) --- p.30 / Chapter 4.3 --- Applicability of the Base Pair Replacement Approach --- p.31 / Chapter 4.3.1 --- Chemical Shifts and 3JH1´ةH2´ة of refT.A(XTY) Sequences --- p.31 / Chapter 4.3.2 --- Correction factors Extracted from the Top Strands of refA.A(XAY) and refT.A(XTY) --- p.31 / Chapter 4.3.3 --- Prediction Result Using Correction Factors Extracted from the Top Strands of refA.A(XAY) and refT.A(XTY) --- p.33 / Chapter 5 --- Conclusion --- p.35 / Appendix I NOE Sequential Assignment of refA.T(XAY) - (A) Aromatic Protons at 25 °C; (B) Labile Protons at 25 °C --- p.36 / Appendix II NOE Sequential Assignment of refA.A(XAY) - (A) Aromatic Protons at 25 °C; (B) Labile Protons at 5 °C --- p.40 / Appendix III H1'-H2'/H2´ح region of DQF-COSY Spectra of refA.T(XAY) at 25 °C --- p.44 / Appendix IV H1'- H2'/H2´ح region of DQF-COSY Spectra of refA.A(XAY) at 25 °C --- p.46 / Appendix V H3' region of HSQC Spectra of refA T(XAY) at 25 °C --- p.48 / Appendix VI H3' region of 1H-31̐ư HSQC Spectra of refA.A(XAY) at 25 °C --- p.50 / Appendix VII 3JH1'h2'1H and 31P Chemical Shifts of refA T(XAY) --- p.52 / Appendix VIII 3JH1'H2'and 31P Chemical Shifts of refA.A(XTY) --- p.60 / Appendix IX NOE Sequential Assignment of refT .A(XTY) - (A) Aromatic Protons at 25 °C; (B) Labile Protons at 25 °C --- p.68 / Appendix X H1'-H2'/H2''region of DQF-COSY Spectra of refT.A(XTY) --- p.72 / Appendix XI H3'region of H-31P HSQC Spectra of refT.A(XTY) --- p.74 / Appendix XII 3JH1'H2'1H and 31P Chemical Shifts of refT.A(XTY) --- p.76 / Appendix XIII Chemical Shifts of Testing Sequences --- p.84 / Reference --- p.92

The purpose of this thesis was two fold: (i) The synthesis and characterization of SF5 containing dienes. (ii) The characterization of hydro/fluorocarbon compounds containing SF5/S02F groups via their 13C NMR spectra. A new SF5CH2CHBrCH2CF=CF2 was prepared and characterized as a precursor to new dielectric polymers. This new adduct was made from the reaction of pentafluorothio bromide with l,l,2-trifluoro-1,4-pentadiene. A SF5-diene was prepared from the reaction of pentafluorothio chloride with acetylene. This reaction involves a radical addition mechanism. The SF5 group is bonded to the carbon atom carrying the most hydrogens. SF5 - dienes are capable of undergoing different reactions, such as polymerization. Fluorocarbon sulfonyl fluorides (RS02F), which have been synthesized in our lab, were characterized by their 13C NMR spectra. The 13C NMR data of these sulfonyl fluorides show chemical shift values for the methyl and methylene groups next to a fluoroalkyl sulfonyl fluoride group in the 52.8-65.7 ppm range. The spectra showed that the inductive effect of electronegative substituents has a major influence on the 1Jc-F and 1Jc-H coupling. Infrared, 1H, 19F and 13C nuclear magnetic resonance and mass spectra are presented to support the assigned structure for the new compounds, SF5CH=CHCH=CHC1 and SF5CH2CHBrCH2CF=CF2.

The behavior of surfactants in solution has been and still is of scientific, technological, and industrial interest. The micelle forming compounds sodium N( octyloxycarbonyl)sarcosinate (NaOcSarc), and sodium N-(decyloxycarbonyl)sarcosinate (NaDecSarc) show in aqueous solution two lH NMR N-methyl peaks arising from a possible cis- or trans-conformation. The relative population of the N-methyl peaks depends mostly on the concentration of surfactant indicating micelle formation. Upon heating the two peaks start to coalesce and finally appear as one single peak . The temperature range in which this phenomenon occurs is from 25°C to 65°C. The primary interest of this study was to determine the activation parameters of rotation about the carbonyl-nitrogen (C-N) bond. Dynamic nuclear magnetic resonance spectroscopy was employed to approach this problem. A complete bandshape analysis was performed in order to calculate the free energy (G++), enthalpy (H++), and entropy (S++) of activation. The effect of a different counter ion (Li+) and sodium chloride salt addition were tested for possible changes of the activation parameters. Studies in nonaqeous solvents were conducted with the free acid form of the mentioned carbarnates. Dimethylsulfoxide and chloroform were chosen as organic solvents for these particular experiments. The critical micellar concentrations of all surfactants were determined, and the assignment of the individual N-methyl peaks to the correspondend conformation could be unambiguously shown by a two dimensional NMR experiment. The cmc's show strong salt dependence. The effect of a lithium as an alternative counter ion has a less drastic effect. Micellization seems not to occur in the free acid cases. Interestingly, the surfactants show stronger salt dependence than micellization dependence upon the activation parameters, indicating that solvent exposure occurs at the C-N partial double bond and considerable deformation of the ideal spherical shape.

Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (p. 119-136).

This thesis includes a summary of some of the early developments of M.IR and NQR detection. Elementary introduction to NQR detection is also discussed. Finally the construction of a high level NQR Spectrometer operating in the regenerative mode is treated. This regenerative spectrometer, originally designed by D. Sill, M. Hayek, Y. Alon, and A. Simievic and published in Rev. Sci. Instr. 38, 11 (1967), is discussed extensively.Ball State UniversityMuncie, IN 47306

The increase of calcium in the cell can induce cellular functions such as fertilization, cell division and cell communication. Calcium (Ca2+) carries out these processes through proteins called calcium sensors. An important calcium modulator is calmodulin. Calmodulin has four possible Ca2+ binding sites that have the characteristic helix-loop-helix (EF hand) motif. When the EF hands bind to Ca2+, methionine rich hydrophobic patches are exposed allowing for CaM to interact with target proteins. However, there are proteins that can interact with CaM at low levels of Ca2+ or in the absence of Ca2+. An enzyme that is activated by CaM is nitric oxide synthase (NOS), which converts L-arginine to L-citrulline and nitric oxide (•NO), where •NO is used to carry out important cellular functions. There are three isoforms of the enzyme; endothelial, neuronal and inducible NOS. The first two isoforms are activated by Ca2+-bound CaM when there is an influx of Ca2+ and are therefore Ca2+-dependent whereas inducible NOS (iNOS) is activated and binds tightly to CaM regardless of the Ca2+ concentration and is therefore Ca2+-independent. Of particular interest is the iNOS enzyme, since no three-dimensional structures of the reductase domain or the CaM-binding region have been solved. All three isoforms of NOS exist as homodimers, where each monomer consisting of a reductase domain and an oxygenase domain separated by a CaM-binding region. The reductase domain contains binding sites for NADPH and the flavins, FAD and FMN, which facilitate electron transfer from the NADPH to the catalytic heme in the oxygenase domain of the opposite monomer. The transfer of electrons from the FAD to the heme is carried out by the FMN domain which is proposed to swing between the two docking points since the distance between the two points is too large for electron transfer. This electron transfer point is under the control of CaM, which is essential for NOS activation. This dynamic process and the direct role of CaM have yet to be observed structurally. A method to monitor dynamics structurally is through the use of nuclear magnetic resonance (NMR) spectroscopy. Therefore as the first step to determine the NMR structure of the FMN domain with the CaM-binding region, the structure of the iNOS CaM-binding region bound to CaM will be determined. The structure will allow for further characterization and identification of important interactions between the iNOS CaM-binding region and CaM which contribute to the unique properties of iNOS.

The increase of calcium in the cell can induce cellular functions such as fertilization, cell division and cell communication. Calcium (Ca2+) carries out these processes through proteins called calcium sensors. An important calcium modulator is calmodulin. Calmodulin has four possible Ca2+ binding sites that have the characteristic helix-loop-helix (EF hand) motif. When the EF hands bind to Ca2+, methionine rich hydrophobic patches are exposed allowing for CaM to interact with target proteins. However, there are proteins that can interact with CaM at low levels of Ca2+ or in the absence of Ca2+. An enzyme that is activated by CaM is nitric oxide synthase (NOS), which converts L-arginine to L-citrulline and nitric oxide (•NO), where •NO is used to carry out important cellular functions. There are three isoforms of the enzyme; endothelial, neuronal and inducible NOS. The first two isoforms are activated by Ca2+-bound CaM when there is an influx of Ca2+ and are therefore Ca2+-dependent whereas inducible NOS (iNOS) is activated and binds tightly to CaM regardless of the Ca2+ concentration and is therefore Ca2+-independent. Of particular interest is the iNOS enzyme, since no three-dimensional structures of the reductase domain or the CaM-binding region have been solved. All three isoforms of NOS exist as homodimers, where each monomer consisting of a reductase domain and an oxygenase domain separated by a CaM-binding region. The reductase domain contains binding sites for NADPH and the flavins, FAD and FMN, which facilitate electron transfer from the NADPH to the catalytic heme in the oxygenase domain of the opposite monomer. The transfer of electrons from the FAD to the heme is carried out by the FMN domain which is proposed to swing between the two docking points since the distance between the two points is too large for electron transfer. This electron transfer point is under the control of CaM, which is essential for NOS activation. This dynamic process and the direct role of CaM have yet to be observed structurally. A method to monitor dynamics structurally is through the use of nuclear magnetic resonance (NMR) spectroscopy. Therefore as the first step to determine the NMR structure of the FMN domain with the CaM-binding region, the structure of the iNOS CaM-binding region bound to CaM will be determined. The structure will allow for further characterization and identification of important interactions between the iNOS CaM-binding region and CaM which contribute to the unique properties of iNOS.