subject:(Relaxation chemistry)

University of Colorado

1. Park, Hee Young. Stress Relaxation by Addition-fragmentation Chain Transfer in Glassy Polymer Networks.

Degree: PhD, Chemical & Biochemical Engineering, 2011, University of Colorado

URL: https://scholar.colorado.edu/chbe_gradetds/15

► Since polymer materials have come to dominate our life by replacing many other, more traditional materials, any endeavors to improve their performance have heightened… (more)

▼ Since polymer materials have come to dominate our life by replacing many other, more traditional materials, any endeavors to improve their performance have heightened importance. Here, we have strived to develop methodologies to reduce and understanding of the processes relevant to the origins of polymerization-induced shrinkage stress. In this thesis, addition-fragmentation chain transfer (AFCT) was utilized to reduce the shrinkage stress through network relaxation and adaptation by radical-mediated bond rearrangement that occurs throughout the polymerization. In previous studies, the presence of the allyl sulfide functional group was shown to reduce the final stress in thiol-ene resins via AFCT. Unfortunately, thiol-ene polymerizations often yield elastomeric materials with low glass transition temperatures (Tgs) that are illsuited for structural applications. To extend the utility of AFCT into structural applications, AFCT-capable monomers have been incorporated into many systems to achieve both low stress and excellent mechanical properties by designing chemical structure of monomers and by exploration of the polymerization and relaxation mechanisms. In particular, incorporation of AFCT-capable monomers into conventional dental resins was investigated to generate novel low stress dental composites. This thesis has demonstrated the development and implementation of thiol-ene and thiol-yne based monomers that are capable of undergoing AFCT to reduce polymerization stress further in a glassy polymer and its application for the conventional glassy methacrylate-based dental resins. Additionally, novel monomers that undergo AFCT were developed and implemented in methacrylate-based resins that undergo propagation exclusively through chain growth mechanisms. Since direct incorporation of the allyl sulfide in methacrylatebased systems was not effective for stress relaxation with large amounts of methacrylate, trithiocarbonates were used in place of allyl sulfides in dimethacrylate monomers, where the trithiocarbonate enables reversible reactions with the methacrylic radicals. The trithiocarbonate-based dimethacrylate demonstrated 65 % stress reduction compared with the standard BisGMA-TEGDMA composite while demonstrating fracture toughness which was slightly higher than the control BisGMA-TEGDMA composite indicating that TTCDMA and related monomers represent excellent candidates for reactive diluents in BisGMA-based dental materials. The improved understanding of the trithiocarbonate functional group will broadly expand its utility for a wide range of applications such as coatings, microelectronics, photoresists, and dental materials. Advisors/Committee Members: Christopher N. Bowman, Jeffrey W. Stansbury, Kristi S. Anseth.

Subjects/Keywords: photopolymerization; stress relaxation; Polymer Chemistry

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APA (6^th Edition):

Park, H. Y. (2011). Stress Relaxation by Addition-fragmentation Chain Transfer in Glassy Polymer Networks. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/chbe_gradetds/15

Chicago Manual of Style (16^th Edition):

Park, Hee Young. “Stress Relaxation by Addition-fragmentation Chain Transfer in Glassy Polymer Networks.” 2011. Doctoral Dissertation, University of Colorado. Accessed January 26, 2021. https://scholar.colorado.edu/chbe_gradetds/15.

MLA Handbook (7^th Edition):

Park, Hee Young. “Stress Relaxation by Addition-fragmentation Chain Transfer in Glassy Polymer Networks.” 2011. Web. 26 Jan 2021.

Vancouver:

Park HY. Stress Relaxation by Addition-fragmentation Chain Transfer in Glassy Polymer Networks. [Internet] [Doctoral dissertation]. University of Colorado; 2011. [cited 2021 Jan 26]. Available from: https://scholar.colorado.edu/chbe_gradetds/15.

Council of Science Editors:

Park HY. Stress Relaxation by Addition-fragmentation Chain Transfer in Glassy Polymer Networks. [Doctoral Dissertation]. University of Colorado; 2011. Available from: https://scholar.colorado.edu/chbe_gradetds/15

2. Aggarwal, Priyanka. Relaxation of Metals and Their Impact on Nitroxides.

Degree: PhD, Chemistry and Biochemistry, 2016, U of Denver

URL: https://digitalcommons.du.edu/etd/1182

► Pulsed and continuous wave electron spin resonance were used to characterize the relaxation rates of selected paramagnetic metals at 5 to 15 K or… (more)

Subjects/Keywords: Relaxation rates; Electron Spin-lattice; Chemistry

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APA (6^th Edition):

Aggarwal, P. (2016). Relaxation of Metals and Their Impact on Nitroxides. (Doctoral Dissertation). U of Denver. Retrieved from https://digitalcommons.du.edu/etd/1182

Chicago Manual of Style (16^th Edition):

Aggarwal, Priyanka. “Relaxation of Metals and Their Impact on Nitroxides.” 2016. Doctoral Dissertation, U of Denver. Accessed January 26, 2021. https://digitalcommons.du.edu/etd/1182.

MLA Handbook (7^th Edition):

Aggarwal, Priyanka. “Relaxation of Metals and Their Impact on Nitroxides.” 2016. Web. 26 Jan 2021.

Vancouver:

Aggarwal P. Relaxation of Metals and Their Impact on Nitroxides. [Internet] [Doctoral dissertation]. U of Denver; 2016. [cited 2021 Jan 26]. Available from: https://digitalcommons.du.edu/etd/1182.

Council of Science Editors:

Aggarwal P. Relaxation of Metals and Their Impact on Nitroxides. [Doctoral Dissertation]. U of Denver; 2016. Available from: https://digitalcommons.du.edu/etd/1182

3. Han, Thi-Hong-Liên. Etudes de la fonction de la frataxine : relations avec l'homéostasie métallique et le stress oxydant. : Functional studies of Frataxin : relations with metal homeostasis and oxidatives stress.

Degree: Docteur es, Chimie. Physico-Chimie, 2016, Sorbonne Paris Cité

URL: http://www.theses.fr/2016USPCC288

►

La frataxine est une protéine mitochondriale bien conservée de la bactérie à l’homme. La déficience de la frataxine chez l’homme entraine une maladie neurodégénérative grave,… (more)

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La frataxine est une protéine mitochondriale bien conservée de la bactérie à l’homme. La déficience de la frataxine chez l’homme entraine une maladie neurodégénérative grave, appelée Ataxie de Friedreich. Cette protéine a été découverte dans les années 90s et depuis sa fonction physiologique exacte n’est toujours pas connue. La frataxine joue un rôle important dans la biosynthèse des centres Fe-S dans l’homéostasie du fer et/ou dans la protection contre le stress oxydant. Dans cette thèse, nous nous intéressons aux interactions entre la protéine et d’autres molécules, comme certains métaux mitochondriaux ou protéines pour mieux comprendre la fonction de la frataxine dans la cellule. Lors de ce travail, la frataxine de levure (Yfh1) a été synthétisée par la technique de l’ADN recombinant, puis purifiée pour les études physico-chimiques. La flavohémoglobine (Yhb1)qui joue le rôle important dans la détoxification de NO (un agent du stress oxydatif et nitrosatif) a été aussi exprimée et purifiée selon le même principe. Ensuite, nous avons étudié la thermodynamique et la cinétique de la complexation de Yfh1 par les métaux mitochondriaux comme Fe, Cu, Mn, Zn, ainsi qu’avec les protéines impliquées dans le système antioxydant comme les superoxydes dismutases, CuZnSOD et MnSOD, et la flavohémoglobine. Ces résultats montrent tout d’abord que Yfh1 interagit avec tous les métaux mitochondriaux,néanmoins elle présente une meilleure affinité pour le cuivre et le manganèse. Par la suite, nous mettons en évidence le rôle remarquable de la frataxine dans le système antioxydant. Nous attribuons ainsi à la frataxine un rôle de protéine multifonctionnelle : « régulateur » dans le métabolisme des métaux.

The frataxin is a mitochondrial protein which is highly conserved during the evolution. The deficiency of frataxinin human induces a neurodegenerative disease: Friedreich’s ataxia. This protein was discovered in the nineties.However, its functions are always opened questions. It has been shown that frataxin participates in the assemblyof Fe-S cluster, as well as the iron homeostasis and cellular antioxidant system. The interactions between frataxinand others molecules, such as metals or proteins, are necessary for a better understanding of protein’s functions.In this work, we synthesized a yeast frataxin homologue (Yfh1) by DNA recombinant technique, and thenpurified it for cell free studies. Yeast flavohemoglobin (Yhb1), which is responsible for the detoxification of NO(an oxidative and nitrosative stress agent), was also isolated. We started by determining the thermodynamics andkinetics of the physiological interaction between Yfh1 and mitochondrial metals, such as Fe, Cu, Mn and Zn, aswell as the interaction with the gatekeepers in the anti-oxidative stress such as superoxide dismutases, CuZnSOD& MnSOD, and Yhb1. We underline here, in the first part the unspecific interaction of Yfh1 with mitochondrialmetals, and more especially the higher affinity of Yfh1 for copper and manganese than for iron. We also confirmthe remarkable…

Advisors/Committee Members: Ha-Duong, Nguyêt-Thanh (thesis director), El Hage Chahine, Jean-Michel (thesis director).

Subjects/Keywords: Homéostasie métallique; Métaux mitochondriaux; Relaxation chimique; Metal homeostasis; Mitochondrial metals; Relaxation chemistry

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APA (6^th Edition):

Han, T. (2016). Etudes de la fonction de la frataxine : relations avec l'homéostasie métallique et le stress oxydant. : Functional studies of Frataxin : relations with metal homeostasis and oxidatives stress. (Doctoral Dissertation). Sorbonne Paris Cité. Retrieved from http://www.theses.fr/2016USPCC288

Chicago Manual of Style (16^th Edition):

Han, Thi-Hong-Liên. “Etudes de la fonction de la frataxine : relations avec l'homéostasie métallique et le stress oxydant. : Functional studies of Frataxin : relations with metal homeostasis and oxidatives stress.” 2016. Doctoral Dissertation, Sorbonne Paris Cité. Accessed January 26, 2021. http://www.theses.fr/2016USPCC288.

MLA Handbook (7^th Edition):

Han, Thi-Hong-Liên. “Etudes de la fonction de la frataxine : relations avec l'homéostasie métallique et le stress oxydant. : Functional studies of Frataxin : relations with metal homeostasis and oxidatives stress.” 2016. Web. 26 Jan 2021.

Vancouver:

Han T. Etudes de la fonction de la frataxine : relations avec l'homéostasie métallique et le stress oxydant. : Functional studies of Frataxin : relations with metal homeostasis and oxidatives stress. [Internet] [Doctoral dissertation]. Sorbonne Paris Cité; 2016. [cited 2021 Jan 26]. Available from: http://www.theses.fr/2016USPCC288.

Council of Science Editors:

Han T. Etudes de la fonction de la frataxine : relations avec l'homéostasie métallique et le stress oxydant. : Functional studies of Frataxin : relations with metal homeostasis and oxidatives stress. [Doctoral Dissertation]. Sorbonne Paris Cité; 2016. Available from: http://www.theses.fr/2016USPCC288

University of Michigan

4. Dethoff, Elizabeth A. Structural and Dynamic Basis for Assembly of the HIV-1 TAR-Tat Ribonucleoprotein Complex.

Degree: PhD, Chemistry, 2011, University of Michigan

URL: http://hdl.handle.net/2027.42/86484

► The transactivation response element (TAR), located at the 5' end of the HIV-1 genome, regulates the transcription elongation step of viral RNA. The TAR stem-loop… (more)

▼ The transactivation response element (TAR), located at the 5' end of the HIV-1 genome, regulates the transcription elongation step of viral RNA. The TAR stem-loop binds the HIV viral transactivator protein (Tat), which enhances viral transcription by recruiting the positive transcription elongation factor b (P-TEFb). The TAR-Tat interaction and formation of the TAR/Tat/P-TEFb ribonucleoprotein (RNP) complex remains poorly understood from a structural and dynamic standpoint. To better understand the formation of this complex, we have studied the structural and dynamic features of free TAR to elucidate motions in both the bulge and apical loop that may be important for adaptive recognition of protein targets and, ultimately, for anti-viral therapeutic design. We used a combination of nuclear magnetic resonance (NMR), molecular dynamics (MD), and mutagenesis to characterize the structural dynamics of free TAR. Residual dipolar couplings (RDCs), motionally-decoupled 13C relaxation (R1, R2), and 13C R1ρ relaxation dispersion were used in combination to characterize global and local motions occurring on fast (ps to ns) and slow (us to ms) timescales. These results were compared to an MD simulation of TAR. Our results show that the apical loop and bulge act as independent dynamical centers, with the apical loop undergoing complex dynamics on the microsecond to picosecond timescale that may be important for adaptive recognition. We have characterized a lowly-populated structure of the loop that is otherwise “invisible” to traditional NMR techniques, representing the first-ever characterization of an “invisible” state of an RNA loop by NMR. Overall, our results establish a broadly useful approach for characterizing the dynamics of RNA loops and shed light on the relationship between dynamics and biological function for the TAR element in the HIV genome. Advisors/Committee Members: Al-Hashimi, Hashim M. (committee member), Brooks Iii, Charles L. (committee member), Engelke, David R. (committee member), Ramamoorthy, Ayyalusamy (committee member).

Subjects/Keywords: NMR; RNA; RDC; Relaxation; HIV-1; Biological Chemistry; Chemistry; Science

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APA (6^th Edition):

Dethoff, E. A. (2011). Structural and Dynamic Basis for Assembly of the HIV-1 TAR-Tat Ribonucleoprotein Complex. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/86484

Chicago Manual of Style (16^th Edition):

Dethoff, Elizabeth A. “Structural and Dynamic Basis for Assembly of the HIV-1 TAR-Tat Ribonucleoprotein Complex.” 2011. Doctoral Dissertation, University of Michigan. Accessed January 26, 2021. http://hdl.handle.net/2027.42/86484.

MLA Handbook (7^th Edition):

Dethoff, Elizabeth A. “Structural and Dynamic Basis for Assembly of the HIV-1 TAR-Tat Ribonucleoprotein Complex.” 2011. Web. 26 Jan 2021.

Vancouver:

Dethoff EA. Structural and Dynamic Basis for Assembly of the HIV-1 TAR-Tat Ribonucleoprotein Complex. [Internet] [Doctoral dissertation]. University of Michigan; 2011. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/2027.42/86484.

Council of Science Editors:

Dethoff EA. Structural and Dynamic Basis for Assembly of the HIV-1 TAR-Tat Ribonucleoprotein Complex. [Doctoral Dissertation]. University of Michigan; 2011. Available from: http://hdl.handle.net/2027.42/86484

Miami University

5. Baum, Robert Ray, Jr. Spectroscopic Studies of a Series of Co(II) ß-diketonates.

Degree: PhD, Chemistry, 2016, Miami University

URL: http://rave.ohiolink.edu/etdc/view?acc_num=miami1479897468999773

► In an extension of previous research by the Tierney group, a series of cobalt(II) ß-diketonates with clear dynamics was found in the literature for further… (more)

Subjects/Keywords: Chemistry; Inorganic Chemistry; beta-diketonates; nuclear magnetic resonance; paramagnetic relaxation enhancements

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APA (6^th Edition):

Baum, Robert Ray, J. (2016). Spectroscopic Studies of a Series of Co(II) ß-diketonates. (Doctoral Dissertation). Miami University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=miami1479897468999773

Chicago Manual of Style (16^th Edition):

Baum, Robert Ray, Jr. “Spectroscopic Studies of a Series of Co(II) ß-diketonates.” 2016. Doctoral Dissertation, Miami University. Accessed January 26, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=miami1479897468999773.

MLA Handbook (7^th Edition):

Baum, Robert Ray, Jr. “Spectroscopic Studies of a Series of Co(II) ß-diketonates.” 2016. Web. 26 Jan 2021.

Vancouver:

Baum, Robert Ray J. Spectroscopic Studies of a Series of Co(II) ß-diketonates. [Internet] [Doctoral dissertation]. Miami University; 2016. [cited 2021 Jan 26]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=miami1479897468999773.

Council of Science Editors:

Baum, Robert Ray J. Spectroscopic Studies of a Series of Co(II) ß-diketonates. [Doctoral Dissertation]. Miami University; 2016. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=miami1479897468999773

University of Oxford

6. Agarwal, Amit. Simulation studies of recombination kinetics and spin dynamics in radiation chemistry.

Degree: PhD, 2011, University of Oxford

URL: http://ora.ox.ac.uk/objects/uuid:0b46a048-a2c9-4964-81e1-f526cc00c03d ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.580867

► Radiation chemistry is concerned with understanding the chemical kinetics following the application of ionising radiation. There are two main methods for modelling recom- bination and… (more)

▼ Radiation chemistry is concerned with understanding the chemical kinetics following the application of ionising radiation. There are two main methods for modelling recom- bination and spin dynamics in radiation chemical systems: The Monte Carlo random flights algorithm, in which the trajectories of the diffusing species are followed ex- plicitly and the Independent Reaction Times (IRT) algorithm, where reaction times are sampled from appropriate marginal distribution functions. This thesis reports develop- ments to both methods, and applies them to better understand experimental findings, particularly spin relaxation effects. Chapter 4 introduces current simulation techniques and presents newly developed algorithms and simulation programs (namely Hybrid and Slice) for modelling spatially dependent spin effects. A new analytical approximation for accurately treating ion-pair recombination in low-permittivity solvents in also presented in this chapter. Chapter 5 explores the photodissociation of H₂O₂, where there is some controversy in the literature on the spin state of the precursor. This chapter explores the possibility of reproducing the observed spin polarisation phase using the Radical Pair Mechanism. Chapter 6 presents two new algorithms for treating reactive products in the IRT framework. These have been tested for two chemical systems: (i) photodissociation of H₂O₂ where the ·OH are scavengeable; (ii) water photolysis which produces H⁺, ·OH and e⁻__aq. In the latter case a careful handling of three body correlations is required. Chapter 7 presents simulation results which suggest a strong correlation between scavenging and ion recombination in low permittivity solvents. A path decomposition method has been devised that allows IRT simulations to be corrected for this effect. Chapter 8 presents evidence for spin-entanglement and cross-recombination to act as an extra source of relaxation for ion-recombination in low permittivity solvents. It is hypothesised this effect contributes to the anomalous relaxation times observed for certain cyclic hydrocarbons. Chapter 9 presents an extension of the IRT simulation method to micelles. The kinetics are shown to be accurately described using the mean reaction time and the exponential approximation.

Subjects/Keywords: 541.3; Physical & theoretical chemistry; Computational chemistry; radiation chemistry; spurs; microscopic simulation; spin relaxation

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APA (6^th Edition):

Agarwal, A. (2011). Simulation studies of recombination kinetics and spin dynamics in radiation chemistry. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:0b46a048-a2c9-4964-81e1-f526cc00c03d ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.580867

Chicago Manual of Style (16^th Edition):

Agarwal, Amit. “Simulation studies of recombination kinetics and spin dynamics in radiation chemistry.” 2011. Doctoral Dissertation, University of Oxford. Accessed January 26, 2021. http://ora.ox.ac.uk/objects/uuid:0b46a048-a2c9-4964-81e1-f526cc00c03d ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.580867.

MLA Handbook (7^th Edition):

Agarwal, Amit. “Simulation studies of recombination kinetics and spin dynamics in radiation chemistry.” 2011. Web. 26 Jan 2021.

Vancouver:

Agarwal A. Simulation studies of recombination kinetics and spin dynamics in radiation chemistry. [Internet] [Doctoral dissertation]. University of Oxford; 2011. [cited 2021 Jan 26]. Available from: http://ora.ox.ac.uk/objects/uuid:0b46a048-a2c9-4964-81e1-f526cc00c03d ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.580867.

Council of Science Editors:

Agarwal A. Simulation studies of recombination kinetics and spin dynamics in radiation chemistry. [Doctoral Dissertation]. University of Oxford; 2011. Available from: http://ora.ox.ac.uk/objects/uuid:0b46a048-a2c9-4964-81e1-f526cc00c03d ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.580867

East Carolina University

7. Obondi, Christopher Otara. NMR Studies into the Potential Interactions of Fullerene C[subscript]60, with Tetraphenylporphyrin, H[subscript]2[TPP] and Some of its Derivatives.

Degree: MS, Chemistry, 2011, East Carolina University

URL: http://hdl.handle.net/10342/3737

► The curved [pi] surface of fullerene, C[subscript]60, shows a tendency to interact with other molecules, making it an interesting target for building supramolecular arrays. The… (more)

▼ The curved [pi] surface of fullerene, C[subscript]60, shows a tendency to interact with other molecules, making it an interesting target for building supramolecular arrays. The interaction can be relative strong and may even exist in solutions, often leading to stable complexes. An important class of the macrocycles that interacts with fullerenes is the porphyrins. In our study, [superscript]1H NMR spectrometric studies have been done to gain information on the nature and the precise interaction site of fullerene 1, with tetraphenylporphyrin, H[subscript]2[TPP] 2, and para-substituted tetraphenylporphyrins, H[subscript]2[(p-X)[subscript]4TPP], where X= CN and OCH[subscript]3 in deuterated chlorobenzene-d[subscript]5(CBZ) and toluene-d[subscript]8. The porphyrin derivatives have been used to investigate any correlation in the interaction site due to changes in substituent. Relaxation rates of the pyrrole and phenyl hydrogen in the porphyrins were determined at temperatures of 288, 298 and 313 K for all the complexes in the presence and in the absence of fullerene, C[subscript]60. To study solvent effects on interactions, Toluene-d[subscript]8 and chlorobenzene-d[subscript]5 solvents were used. Overall, our data indicated that C[subscript]60 interacted with H[subscript]2[TPP] at both the pyrrole and phenyl hydrogen sites however, these intermolecular interaction are not long-lasting in chlorobenzene-d[subscript]5. Â Â The porphyrin derivatives showed that the substituents have an effect on which site is preferred for interaction. For the case of H[subscript]2[(p-OCH[subscript]3)[subscript]4TPP], that has an electron -donating group, both phenyl and pyrrole hydrogen sites interacted with C[subscript]60 , but preferably at the pyrrole hydrogen at all the three temperatures(283, 298, and 313 K). In the case of H[subscript]2[(p-CN)[subscript]4TPP] with an electron-withdrawing group CN, our data indicates that at lower temperature there is a noticeable, but slight preference for the interaction of C[subscript]60 at pyrrole site but is quickly destroyed with an increase in temperature.Â Â Advisors/Committee Members: Rodriguez, Art A. (advisor).

Subjects/Keywords: Chemistry, Physical; Correlation time; C60; Relaxation time; Tetraphenylporphyrin; Physical chemistry; Fullerenes; Porphyrins; Supramolecular chemistry

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APA (6^th Edition):

Obondi, C. O. (2011). NMR Studies into the Potential Interactions of Fullerene C[subscript]60, with Tetraphenylporphyrin, H[subscript]2[TPP] and Some of its Derivatives. (Masters Thesis). East Carolina University. Retrieved from http://hdl.handle.net/10342/3737

Chicago Manual of Style (16^th Edition):

Obondi, Christopher Otara. “NMR Studies into the Potential Interactions of Fullerene C[subscript]60, with Tetraphenylporphyrin, H[subscript]2[TPP] and Some of its Derivatives.” 2011. Masters Thesis, East Carolina University. Accessed January 26, 2021. http://hdl.handle.net/10342/3737.

MLA Handbook (7^th Edition):

Obondi, Christopher Otara. “NMR Studies into the Potential Interactions of Fullerene C[subscript]60, with Tetraphenylporphyrin, H[subscript]2[TPP] and Some of its Derivatives.” 2011. Web. 26 Jan 2021.

Vancouver:

Obondi CO. NMR Studies into the Potential Interactions of Fullerene C[subscript]60, with Tetraphenylporphyrin, H[subscript]2[TPP] and Some of its Derivatives. [Internet] [Masters thesis]. East Carolina University; 2011. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/10342/3737.

Council of Science Editors:

Obondi CO. NMR Studies into the Potential Interactions of Fullerene C[subscript]60, with Tetraphenylporphyrin, H[subscript]2[TPP] and Some of its Derivatives. [Masters Thesis]. East Carolina University; 2011. Available from: http://hdl.handle.net/10342/3737

University of California – Berkeley

8. Young, Ryan Michael. Dynamics of excess electrons in atomic and molecular clusters.

Degree: Chemistry, 2011, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/0wj1n3xv

► Femtosecond time-resolved photoelectron imaging (TRPEI) is applied to the study of excess electrons in clusters as well as to microsolvated anion species. This technique can… (more)

▼ Femtosecond time-resolved photoelectron imaging (TRPEI) is applied to the study of excess electrons in clusters as well as to microsolvated anion species. This technique can be used to perform explicit time-resolved as well as one-color (single- or multiphoton) studies on gas phase species. The first part of this dissertation details time-resolved studies done on atomic clusters with an excess electron, the excited-state dynamics of solvated molecular anions, and charge-transfer dynamics to solvent clusters. The second part summarizes various one-color photoelectron imaging studies on tetrahydrofuran clusters with an excess electron or doped with an iodide ion in order to probe the solvent structure of these clusters. Finally, a mixed study is presented exploring the effect of warmer cluster conditions on both the binding energies and relaxation times of excess electrons in water clusters. Time-resolved studies on mercury cluster anions (Hg)n¯ (7 ≤ n ≤ 20) demonstrate the different timescales of electron-phonon and electron-electron scattering in small systems. Low-energy (1.0-1.5 eV) excitation of the excess electron to a higher-lying electronic state decays via a cascade through the conduction band on a 10-40 ps timescale. Conversely, high-energy (4.7 eV) excitation of an electron from the valence band into the conduction band opens a second relaxation pathway: emission of the excess electron via Auger decay. The larger number of charge carriers and the geometrical changes to the cluster following the creation of the valence band hole state increase the relaxation rate, causing relaxation to occur on a 100s of fs timescale. The size dependence of both relaxation timescales becomes much less significant around n = 13 near the van der Waals-to-covalent bonding transition seen in other studies of mercury clusters. The solvated acetonitrile dimer anion, (CH3CN)n¯ (20 ≤ n ≤ 50) is also studied using TRPEI. The dimer anion is selectively excited with 790 nm (1.57 eV) pulses and probed with 395 nm (3.14 eV) pulses, detaching both the ground and excited states. The excited clusters are observed to autodetach on a timescale of ~200-300 fs with no size dependence. The excited-state autodetachment shows a direct link for the first time between the two different binding motifs observed in the gas phase with the two isomers observed in solution from their absorption profiles. Electron solvation dynamics following charge-transfer-to-solvent excitation from iodide to small methanol clusters, I¯(CH3OH)n (4 ≤ n ≤ 11) are also examined with TRPEI. After electron transfer, the excited state spectrum undergoes significant evolution in both its position and shape. Considerations of the geometries of the initial iodide-doped methanol cluster as well as the intermediate bare methanol anion cluster and final neutral clusters suggest the electron is solvated, as at least one methanol molecule rotates to bring its hydroxyl group inward toward the cluster center, maximizing the hydrogen bond…

Subjects/Keywords: Physical chemistry; Clusters; photoelectron; relaxation dynamics; solvated electron; solvent dynamics; spectroscopy

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APA (6^th Edition):

Young, R. M. (2011). Dynamics of excess electrons in atomic and molecular clusters. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/0wj1n3xv

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Young, Ryan Michael. “Dynamics of excess electrons in atomic and molecular clusters.” 2011. Thesis, University of California – Berkeley. Accessed January 26, 2021. http://www.escholarship.org/uc/item/0wj1n3xv.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Young, Ryan Michael. “Dynamics of excess electrons in atomic and molecular clusters.” 2011. Web. 26 Jan 2021.

Vancouver:

Young RM. Dynamics of excess electrons in atomic and molecular clusters. [Internet] [Thesis]. University of California – Berkeley; 2011. [cited 2021 Jan 26]. Available from: http://www.escholarship.org/uc/item/0wj1n3xv.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Young RM. Dynamics of excess electrons in atomic and molecular clusters. [Thesis]. University of California – Berkeley; 2011. Available from: http://www.escholarship.org/uc/item/0wj1n3xv

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – Berkeley

9. Avalos, Claudia Esther. Detection and Polarization of Nuclear and Electron Spins using Nitrogen-Vacancy Centers.

Degree: Chemistry, 2014, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/0dp439q7

► Magnetic resonance spectroscopy is one of the most powerful spectroscopic tools for obtaining detailed information about molecular structure. It has also served as a remarkable… (more)

Subjects/Keywords: Physics; Physical chemistry; coherence lifetime; cross-relaxation; magnetometry; nitrogen-vacancy; polarization

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APA (6^th Edition):

Avalos, C. E. (2014). Detection and Polarization of Nuclear and Electron Spins using Nitrogen-Vacancy Centers. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/0dp439q7

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Avalos, Claudia Esther. “Detection and Polarization of Nuclear and Electron Spins using Nitrogen-Vacancy Centers.” 2014. Thesis, University of California – Berkeley. Accessed January 26, 2021. http://www.escholarship.org/uc/item/0dp439q7.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Avalos, Claudia Esther. “Detection and Polarization of Nuclear and Electron Spins using Nitrogen-Vacancy Centers.” 2014. Web. 26 Jan 2021.

Vancouver:

Avalos CE. Detection and Polarization of Nuclear and Electron Spins using Nitrogen-Vacancy Centers. [Internet] [Thesis]. University of California – Berkeley; 2014. [cited 2021 Jan 26]. Available from: http://www.escholarship.org/uc/item/0dp439q7.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Avalos CE. Detection and Polarization of Nuclear and Electron Spins using Nitrogen-Vacancy Centers. [Thesis]. University of California – Berkeley; 2014. Available from: http://www.escholarship.org/uc/item/0dp439q7

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

10. Berenbeim, Jacob. Laser Spectroscopy and Photodynamics of Alternative Nucleobases and Organic Dyes.

Degree: 2017, University of California – eScholarship, University of California

URL: http://www.escholarship.org/uc/item/8kb4h57f

► Resonant excitation multiphoton ionization (REMPI) with TOF mass spectrometry detection was used to study and characterize organic chromophores which play a role in our prebiotic… (more)

▼ Resonant excitation multiphoton ionization (REMPI) with TOF mass spectrometry detection was used to study and characterize organic chromophores which play a role in our prebiotic origins, the medicines we use, and in the paintings and other cultural artifacts we treasure.For our molecules which are prepared in a molecular beam (i.e. cold, neutral, and isolated) we are in the opportune position to compare with state of the art computation. This analysis was invaluable when differentiating alternative nucleobase structures in the chapters on isocytosine and 6-thioguanine, and understanding the effects of intramolecular hydrogen bonding environments when working with anthraquinone dyes. Of great interest was understanding excited state chromophore deactivation from low energy electronic states. The deactivation pathways a molecule takes, be them radiative or non-radiative, have severe implications on the form and function of that molecule. I continued to expand on the photostability centered hypothesis of prebiotic chemistry; that the aromaticity of genetic molecules leave them prone to harsh UV absorption in an ozone-less environment, however, a predisposition to convert electronic to ground state vibrational energy (heat) on an ultrafast timescale supports the prevalence of our canonical bases A, T, G, C, U. The work on isocytosine is exciting both in analogy to biological (keto) G and as a possible xeno or pre-RNA/DNA nucleobase (when paired with complimentary isoguanine). Secondly, 6-thioguanine converts with near unity to a long lived dark state and due to the thiooxo guanine substitution this intersystem crossing happens at an abnormally high rate. The work on anthraquinone dyes was an effort to understand the photostability of these molecules within their historical usage in cultural heritage materials and here I will present our case study on the these dyes and whether they undergo an excited state intramolecular proton transfer (ESIPT) to greatly reduce excited state lifetimes, promoting colorfastness as a function of structure.

Subjects/Keywords: Physical chemistry; dynamics; kinetics; relaxation; rempi; spectrometry; spectroscopy

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APA (6^th Edition):

Berenbeim, J. (2017). Laser Spectroscopy and Photodynamics of Alternative Nucleobases and Organic Dyes. (Thesis). University of California – eScholarship, University of California. Retrieved from http://www.escholarship.org/uc/item/8kb4h57f

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Berenbeim, Jacob. “Laser Spectroscopy and Photodynamics of Alternative Nucleobases and Organic Dyes.” 2017. Thesis, University of California – eScholarship, University of California. Accessed January 26, 2021. http://www.escholarship.org/uc/item/8kb4h57f.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Berenbeim, Jacob. “Laser Spectroscopy and Photodynamics of Alternative Nucleobases and Organic Dyes.” 2017. Web. 26 Jan 2021.

Vancouver:

Berenbeim J. Laser Spectroscopy and Photodynamics of Alternative Nucleobases and Organic Dyes. [Internet] [Thesis]. University of California – eScholarship, University of California; 2017. [cited 2021 Jan 26]. Available from: http://www.escholarship.org/uc/item/8kb4h57f.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Berenbeim J. Laser Spectroscopy and Photodynamics of Alternative Nucleobases and Organic Dyes. [Thesis]. University of California – eScholarship, University of California; 2017. Available from: http://www.escholarship.org/uc/item/8kb4h57f

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of South Carolina

11. Phillips, David Christopher. Power Dependent Study of CDSE-ZNS Quantum Dot Relaxation Dynamics by 2D Muppets.

Degree: MS, Chemistry and Biochemistry, 2012, University of South Carolina

URL: https://scholarcommons.sc.edu/etd/720

► CdSe-ZnS core-shell quantum dot relaxation dynamics are multiexponential and have a strong power dependence. Because single exciton and biexciton populations, are indistinguishable by any-dimensional… (more)

▼ CdSe-ZnS core-shell quantum dot relaxation dynamics are multiexponential and have a strong power dependence. Because single exciton and biexciton populations, are indistinguishable by any-dimensional experiments, there is uncertainty as to whether this power dependence comes from a biexciton or a photo-induced byproduct. Multiple population period transient spectroscopy, (MUPPETS), is a new two-dimensional spectroscopic technique that uses decay-rate variation to investigate heterogeneity in multiexponential processes. In this paper stat dependent behavior is used to isolate and identify the biexciton. The 2D MUPPETS signal shows a rise below 100 ps, and one-dimensional MUPPETS and pump-probe signals do not. A photo-induced byproduct would not explain the rise feature. This early time feature is power dependent. A least squares fit linear regression performed on the measured relaxation curves at each time across the different powers gave two terms, one power independent term and one power dependent term. The power independent terms are the low power limit of a relaxation and are shown to match power independent pump-probe data. The power dependent terms are all of the power dependent components and are shown to match the signal difference between the one-dimensional and two-dimensional MUPPETS measurements below 100 ps. Two-dimensional MUPPETS analysis separates the biexciton and single exciton, and the matches with empirical data confirm their identities. With further analysis, fits that match one-dimensional and two-dimensional data will provide characteristics describing the components, determine the number of components, and identify the behavior of the individual components in each population's dynamics. With successful fits, it can be determined if there is a correlation between the single exciton and biexciton dynamics. Deeper understanding of exciton and biexciton dynamics will help in the synthesis and development of solar cells and other energy harvesting devices. Advisors/Committee Members: Mark A Berg, Hui Wang.

Subjects/Keywords: Chemistry; Physical Sciences and Mathematics; Quantum dot relaxation dynamics

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APA (6^th Edition):

Phillips, D. C. (2012). Power Dependent Study of CDSE-ZNS Quantum Dot Relaxation Dynamics by 2D Muppets. (Masters Thesis). University of South Carolina. Retrieved from https://scholarcommons.sc.edu/etd/720

Chicago Manual of Style (16^th Edition):

Phillips, David Christopher. “Power Dependent Study of CDSE-ZNS Quantum Dot Relaxation Dynamics by 2D Muppets.” 2012. Masters Thesis, University of South Carolina. Accessed January 26, 2021. https://scholarcommons.sc.edu/etd/720.

MLA Handbook (7^th Edition):

Phillips, David Christopher. “Power Dependent Study of CDSE-ZNS Quantum Dot Relaxation Dynamics by 2D Muppets.” 2012. Web. 26 Jan 2021.

Vancouver:

Phillips DC. Power Dependent Study of CDSE-ZNS Quantum Dot Relaxation Dynamics by 2D Muppets. [Internet] [Masters thesis]. University of South Carolina; 2012. [cited 2021 Jan 26]. Available from: https://scholarcommons.sc.edu/etd/720.

Council of Science Editors:

Phillips DC. Power Dependent Study of CDSE-ZNS Quantum Dot Relaxation Dynamics by 2D Muppets. [Masters Thesis]. University of South Carolina; 2012. Available from: https://scholarcommons.sc.edu/etd/720

The Ohio State University

12. Sengupta, Ishita. Solid State NMR Structural Studies of Proteins Modified with Paramagnetic Tags.

Degree: PhD, Chemistry, 2012, The Ohio State University

URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1354321906

► Conventional solid-state nuclear magnetic resonance (SSNMR) methods for the measurement of interatomic distances rely on the measurement of magnetic dipole-dipole couplings between nuclei, which… (more)

▼ Conventional solid-state nuclear magnetic resonance (SSNMR) methods for the measurement of interatomic distances rely on the measurement of magnetic dipole-dipole couplings between nuclei, which become vanishingly small for distances exceeding 5 Å. The introduction of a paramagnetic center into the system of study generates electron-nuclear couplings which are several orders of magnitude larger than internuclear couplings given that the magnetic moment of an unpaired electron is roughly ~660 times larger than that of a proton. As a consequence, interesting spectral effects are observed, including paramagnetic shifts and enhanced transverse and longitudinal nuclear relaxation rates. Most importantly, long range distance restraints can be extracted from these paramagnetic effects and used in the structural analysis of biological macromolecules. This thesis is organized as follows. In Chapter 2, we describe a condensed data collection approach that facilitates rapid acquisition of multidimensional magic-angle spinning solid-state nuclear magnetic resonance (SSNMR) spectra of proteins by combining rapid sample spinning, optimized low-power radiofrequency pulse schemes and covalently attached paramagnetic tags to enhance protein ¹H spin-lattice relaxation. In Chapter 3, we investigate the effects on such measurements of intermolecular electron-nucleus couplings and intrinsic metal binding sites, both of which may potentially complicate the interpretation of Paramagnetic Relaxation Enhancement (PRE) data in terms of the intramolecular protein fold. In Chapter 4, we present an approach that enables rapid determination of the global protein fold via measurements of nuclear paramagnetic relaxation enhancements (PREs) without the use of conventional internuclear distance restraints. Finally, in Chapter 5, we present solid-state NMR studies of the K28C mutant of protein GB1 intentionally modified with 2-[1,4,7,10-tetraazacyclododecan-1-yl]-ethanethiol (TETAC) side chains with a high affinity for transition metal ions like Cu²⁺, ZnZn²⁺, Co²⁺ etc. Advisors/Committee Members: Jaroniec, Christopher P. (Advisor).

Subjects/Keywords: Chemistry; Solid State NMR; proteins; Paramagnetic Relaxation Enhancement

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APA (6^th Edition):

Sengupta, I. (2012). Solid State NMR Structural Studies of Proteins Modified with Paramagnetic Tags. (Doctoral Dissertation). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1354321906

Chicago Manual of Style (16^th Edition):

Sengupta, Ishita. “Solid State NMR Structural Studies of Proteins Modified with Paramagnetic Tags.” 2012. Doctoral Dissertation, The Ohio State University. Accessed January 26, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1354321906.

MLA Handbook (7^th Edition):

Sengupta, Ishita. “Solid State NMR Structural Studies of Proteins Modified with Paramagnetic Tags.” 2012. Web. 26 Jan 2021.

Vancouver:

Sengupta I. Solid State NMR Structural Studies of Proteins Modified with Paramagnetic Tags. [Internet] [Doctoral dissertation]. The Ohio State University; 2012. [cited 2021 Jan 26]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1354321906.

Council of Science Editors:

Sengupta I. Solid State NMR Structural Studies of Proteins Modified with Paramagnetic Tags. [Doctoral Dissertation]. The Ohio State University; 2012. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1354321906

University of Cincinnati

13. Ozkaya Ahmadov, Tevhide. Development of Multifunctional Nanoparticles: From Synthesis to Theranostic Applications.

Degree: PhD, Arts and Sciences: Chemistry, 2016, University of Cincinnati

URL: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1463130977

► The objective of my research is to develop multifunctional nanoparticles for sensing and photodynamic therapy applications. Ethylenediaminetriacetic acid (EDTA)-functionalized silica nanoparticles were synthesized by microemulsion… (more)

▼ The objective of my research is to develop multifunctional nanoparticles for sensing and photodynamic therapy applications. Ethylenediaminetriacetic acid (EDTA)-functionalized silica nanoparticles were synthesized by microemulsion method. The EDTA groups on the nanoparticle surface have the role to chelate with metal ions to form paramagnetic nanoparticles in aqueous solution, which would reduce the relaxation rate of water protons. In this study, [email protected]@Fe³⁺ NPs and [email protected]@Gd³ NPs were used for detection of dopamine and phosphate ion, respectively. The results demonstrate that paramagnetic nanoparticles can be integrated into relaxation based detection schemes while avoiding the aggregation problem commonly associated with more widely used superparamagnetic nanoparticles. Lanthanide-based NaYF₄:Yb³⁺,Tm³⁺ upconversion nanoparticles were synthesized in the presence of polyacrylicacid (PAA) via solvothermal method. This is an one step synthesis method to get uniform, reproducible and biocompatible NaYF₄:Yb,Tm upconversion nanoparticles with –COOH surface functional groups. In this study, we designed a ligase-assisted signal-amplifiable DNA biosensor based on NaYF₄:Yb³⁺,Tm³⁺ UCNPs with high sensitivity and specificity. Silver nanoparticles captured by mesoporous silica nanoparticles with photosensitizer ([email protected]@HPIX) were synthesized using silver nitrate as the silver source, formaldehyde as the reducing agent, CTAB as the template/stabilizer, TEOS/TMS-EDTA as the silane source, sodium hydroxide as the catalyst, and HPIX as the loading photosensitizer. [email protected]@HPIX NPs show strong enhanced singlet oxygen generation because of the strong resonance coupling between surface plasmon Ag nanoparticles and the photosensitizing molecules, consequently demonstrating highly efficient photodynamic inactivation (PDI) efficacy against both gram-positive and gram-negative bacteria. In this study, PDI efficacy of [email protected]@HPIX NPs was tested against a multidrug-resistant strain of <i>Staphylococcus aureus.</i>Theranostic silver nanoparticles were synthesized via a new, robust, simple, and reproducible microwave-assisted method. The EDTA groups on the nanoparticle surface have the role to chelate with Gd³⁺ ions to form paramagnetic nanoparticles in aqueous solution, which would reduce the relaxation rate of water protons. In addition, the surface of [email protected]@Gd³⁺ NPs has the potential to form a lanthanide-porphyrin complex, serving as photosensitizers in photodynamic therapy (PDT). This nanoplatform combines functions of magnetic resonance imaging (MRI) contrast agents and PDI agents in a single nanostructure as theranostics. In this study, we performed a systematic study of multifunctional [email protected]@Gd³⁺@HPIX NPs to assess the PDI efficacy against the MRSA, which is a multidrug-resistant strain of <i>Staphylococcus aureus</i>. In summary, multifunctional nanoparticles, including silica,… Advisors/Committee Members: Zhang, Peng (Committee Chair).

Subjects/Keywords: Chemistry; nanoparticles; magnetic relaxation; singlet oxygen enhancement; sensor; photodynamic therapy; MRSA

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APA (6^th Edition):

Ozkaya Ahmadov, T. (2016). Development of Multifunctional Nanoparticles: From Synthesis to Theranostic Applications. (Doctoral Dissertation). University of Cincinnati. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=ucin1463130977

Chicago Manual of Style (16^th Edition):

Ozkaya Ahmadov, Tevhide. “Development of Multifunctional Nanoparticles: From Synthesis to Theranostic Applications.” 2016. Doctoral Dissertation, University of Cincinnati. Accessed January 26, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1463130977.

MLA Handbook (7^th Edition):

Ozkaya Ahmadov, Tevhide. “Development of Multifunctional Nanoparticles: From Synthesis to Theranostic Applications.” 2016. Web. 26 Jan 2021.

Vancouver:

Ozkaya Ahmadov T. Development of Multifunctional Nanoparticles: From Synthesis to Theranostic Applications. [Internet] [Doctoral dissertation]. University of Cincinnati; 2016. [cited 2021 Jan 26]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1463130977.

Council of Science Editors:

Ozkaya Ahmadov T. Development of Multifunctional Nanoparticles: From Synthesis to Theranostic Applications. [Doctoral Dissertation]. University of Cincinnati; 2016. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1463130977

University of Lund

14. Martins, Joao. Pushing diffusion MRI towards new dimensions.

Degree: 2020, University of Lund

URL: https://lup.lub.lu.se/record/1dd25d68-7047-4919-b14f-e2ab34ce3060 ; https://portal.research.lu.se/ws/files/74289479/Joao_Martins_No_Manuscript.pdf

► Diffusion-MRI techniques allow the non-invasive investigation of microstructural changes in living tissues. However, a detailed interpretation of the data is complicated by the fact that… (more)

▼ Diffusion-MRI techniques allow the non-invasive investigation of microstructural changes in living tissues. However, a detailed interpretation of the data is complicated by the fact that multiple microscopic environments with varying diffusion properties all contribute to the measured signal. To address this problem, we adapt strategies from solid-state NMR spectroscopy and magnetic resonance of porous media to design multidimensional diffusion MRI protocols that can establish correlations between distinct features of the underlying diffusion process. Inversion of the acquired data enables the quantification of tissue heterogeneity with non-parametric distributions of diffusion tensors. The size, shape, and orientation of the estimated diffusion tensors have direct relations to corresponding microstructural properties of biological tissues.In Paper I, we introduced an experimental protocol to establish correlations between diffusion tensor eigenvalues. The proposed approach was extended in Paper II, where we correlated individual diffusion tensor parameters with both longitudinal and transverse relaxation rates. In both papers, experimental validation was conducted using spectroscopic experiments on a set of specially tailored synthetic samples. Multidimensional distributions retrieved from the correlated datasets were found to provide excellent resolution between microscopic environments with distinct diffusion properties.In Paper III, we assessed the performance of our data inversion strategies within a clinical context using in silico data. We found that the proposed model-free algorithm preserves good contrast between systems with different microscopic structures, even though its accuracy is significantly affected by high-levels of experimental noise. The algorithm was also observed to exhibit no biases at infinite signal-to-noise ratios.In Paper IV we combined our diffusion tensor correlation protocols with MRI sequences allowing for sub-millimetre imaging of living tissues. The method was demonstrated with measurements on in vivo mouse brain and was validated using a set of phantoms emulating the diffusion properties of brain tissues.In Papers V and VI we investigated the microscopic heterogeneity of the living human brain with spatially resolved relaxation-diffusion distributions. The retrieved distributions allowed the resolution, characterisation, and mapping of distinct microscopic tissue environments.

Subjects/Keywords: Physical Chemistry; NMR; MRI; diffusion; relaxation; multidimensional diffusion MRI; relaxation-diffusion correlations; Laplace NMR; porous media; tissue microstructure; heterogeneity; anisotropy

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APA (6^th Edition):

Martins, J. (2020). Pushing diffusion MRI towards new dimensions. (Doctoral Dissertation). University of Lund. Retrieved from https://lup.lub.lu.se/record/1dd25d68-7047-4919-b14f-e2ab34ce3060 ; https://portal.research.lu.se/ws/files/74289479/Joao_Martins_No_Manuscript.pdf

Chicago Manual of Style (16^th Edition):

Martins, Joao. “Pushing diffusion MRI towards new dimensions.” 2020. Doctoral Dissertation, University of Lund. Accessed January 26, 2021. https://lup.lub.lu.se/record/1dd25d68-7047-4919-b14f-e2ab34ce3060 ; https://portal.research.lu.se/ws/files/74289479/Joao_Martins_No_Manuscript.pdf.

MLA Handbook (7^th Edition):

Martins, Joao. “Pushing diffusion MRI towards new dimensions.” 2020. Web. 26 Jan 2021.

Vancouver:

Martins J. Pushing diffusion MRI towards new dimensions. [Internet] [Doctoral dissertation]. University of Lund; 2020. [cited 2021 Jan 26]. Available from: https://lup.lub.lu.se/record/1dd25d68-7047-4919-b14f-e2ab34ce3060 ; https://portal.research.lu.se/ws/files/74289479/Joao_Martins_No_Manuscript.pdf.

Council of Science Editors:

Martins J. Pushing diffusion MRI towards new dimensions. [Doctoral Dissertation]. University of Lund; 2020. Available from: https://lup.lub.lu.se/record/1dd25d68-7047-4919-b14f-e2ab34ce3060 ; https://portal.research.lu.se/ws/files/74289479/Joao_Martins_No_Manuscript.pdf

University of California – Riverside

15. Zhou, Xiaoquan. The Spectroscopic-Assisted Studies on Photophysics and Mechanochemistry of Anthracene-Based Materials.

Degree: Chemistry, 2012, University of California – Riverside

URL: http://www.escholarship.org/uc/item/01z60563

► A series of 2,6-dialkoxyanthracenes are synthesized and their photophysical properties in liquid solution and solid state are studied. Both spectral lineshapes and luminescence decay kinetics… (more)

Subjects/Keywords: Physical chemistry; Materials Science; Organic chemistry; Anthracene; Conformational Relaxation; Fluorescence; Frenkel Excitons; Mechanophores; Picosecond

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APA (6^th Edition):

Zhou, X. (2012). The Spectroscopic-Assisted Studies on Photophysics and Mechanochemistry of Anthracene-Based Materials. (Thesis). University of California – Riverside. Retrieved from http://www.escholarship.org/uc/item/01z60563

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zhou, Xiaoquan. “The Spectroscopic-Assisted Studies on Photophysics and Mechanochemistry of Anthracene-Based Materials.” 2012. Thesis, University of California – Riverside. Accessed January 26, 2021. http://www.escholarship.org/uc/item/01z60563.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zhou, Xiaoquan. “The Spectroscopic-Assisted Studies on Photophysics and Mechanochemistry of Anthracene-Based Materials.” 2012. Web. 26 Jan 2021.

Vancouver:

Zhou X. The Spectroscopic-Assisted Studies on Photophysics and Mechanochemistry of Anthracene-Based Materials. [Internet] [Thesis]. University of California – Riverside; 2012. [cited 2021 Jan 26]. Available from: http://www.escholarship.org/uc/item/01z60563.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zhou X. The Spectroscopic-Assisted Studies on Photophysics and Mechanochemistry of Anthracene-Based Materials. [Thesis]. University of California – Riverside; 2012. Available from: http://www.escholarship.org/uc/item/01z60563

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

16. Biller, Joshua R. Nitroxide Radicals for Low Frequency Electron Paramagnetic Resonance Imaging (EPRI).

Degree: PhD, Chemistry and Biochemistry, 2014, U of Denver

URL: https://digitalcommons.du.edu/etd/71

► Optimization of nitroxides as probes for EPR imaging requires detailed understanding of spectral properties such as spin lattice relaxation times, spin packet linewidths, and… (more)

▼ Optimization of nitroxides as probes for EPR imaging requires detailed understanding of spectral properties such as spin lattice relaxation times, spin packet linewidths, and nuclear hyperfine splitting. Initial measurements of relaxation times for six low molecular weight nitroxides at X-band stimulated further measurement at frequencies between 250 MHz and 34 GHz. The impact of tumbling was studied with perdeuterated 2,2,6,6-tetramethyl-4-piperidinyl-1-oxyl (PDT) in five solvents with viscosities resulting in tumbling correlation times, τ_R, between 4 and 50 ps. A set of three ¹⁴N/¹⁵N pairs of nitroxides in water was selected such that τ_R varied between 9 and 19 ps. To test the impact of structure on relaxation, three additional nitroxides with τ_R between 10 and 26 ps were studied. In the fast tumbling regime 1/T₂ ~ 1/T₁ and relaxation is dominated by spin rotation, modulation of A-anisotropy and a thermally activated process. The contribution to 1/T₁ from spin rotation is independent of frequency and decreases as τ_R increases. The modulation of nitrogen hyperfine anisotropy increases as frequency decreases and as τ_R increases, dominating at low frequencies for τ_R~ 15 ps. The modulation of g anisotropy is significant only at 34 GHz. Inclusion of a thermally activated process was required to account for the observation that for most of the radicals, 1/T₁ was smaller at 250 MHz than at 1-2 GHz. The thermally activated process likely arises from intramolecular motions of the nitroxide ring that modulate the isotropic A values. A phantom of three 4 mm tubes containing different ¹⁵N,²H-substituted nitroxides was constructed for use at 250 MHz. Projections for 2D spectral-spatial images were obtained by continuous wave (CW) and rapid scan (RS) EPR using a bimodal cross-loop resonator. Relative to CW projections obtained for the same data acquisition time (5 min), RS projections had significantly improved image quality. All experiments were facilitated by advancements in resonator design and testing, which are also described. Advisors/Committee Members: Gareth R. Eaton, Ph.D..

Subjects/Keywords: Electron Paramagnetic Resonance Imaging (EPRI); Imaging; Nitroxides; Rapid scan; Relaxation; Resonators; Analytical Chemistry; Chemistry; Physical Chemistry

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APA (6^th Edition):

Biller, J. R. (2014). Nitroxide Radicals for Low Frequency Electron Paramagnetic Resonance Imaging (EPRI). (Doctoral Dissertation). U of Denver. Retrieved from https://digitalcommons.du.edu/etd/71

Chicago Manual of Style (16^th Edition):

Biller, Joshua R. “Nitroxide Radicals for Low Frequency Electron Paramagnetic Resonance Imaging (EPRI).” 2014. Doctoral Dissertation, U of Denver. Accessed January 26, 2021. https://digitalcommons.du.edu/etd/71.

MLA Handbook (7^th Edition):

Biller, Joshua R. “Nitroxide Radicals for Low Frequency Electron Paramagnetic Resonance Imaging (EPRI).” 2014. Web. 26 Jan 2021.

Vancouver:

Biller JR. Nitroxide Radicals for Low Frequency Electron Paramagnetic Resonance Imaging (EPRI). [Internet] [Doctoral dissertation]. U of Denver; 2014. [cited 2021 Jan 26]. Available from: https://digitalcommons.du.edu/etd/71.

Council of Science Editors:

Biller JR. Nitroxide Radicals for Low Frequency Electron Paramagnetic Resonance Imaging (EPRI). [Doctoral Dissertation]. U of Denver; 2014. Available from: https://digitalcommons.du.edu/etd/71

University of Michigan

17. Nikolova, Evgenia Nikolaevna. The Double Helix in Motion: New Insights into Sequence-specific, Functional DNA Dynamics Using NMR Spectroscopy.

Degree: PhD, Chemical Biology, 2011, University of Michigan

URL: http://hdl.handle.net/2027.42/89648

► DNA is a highly flexible molecule that undergoes a variety of structural transitions in response to cellular cues. Sequence-directed variations in the canonical double helix… (more)

▼ DNA is a highly flexible molecule that undergoes a variety of structural transitions in response to cellular cues. Sequence-directed variations in the canonical double helix structure that retain Watson-Crick base-pairing play important roles in DNA recognition, topology, and nucleosome positioning. Here, we use NMR relaxation methods to study sequence-directed dynamics occurring at picosecond to millisecond timescales in variable size DNA duplexes. Traditionally, atomic-level spin relaxation studies of DNA dynamics have been limited to short duplexes, in which sensitivity to biologically relevant nanosecond fluctuations is often inadequate. We introduce a method for preparing residue-specific 13C/15N-labeled elongated DNA along with a strategy for establishing resonance assignments and apply it towards probing fast inter-helical bending motions induced by an adenine tract. Our results suggest the presence of elevated A-tract independent end-fraying and/or bending internal nanosecond motions, which evade detection in short constructs and that penetrate deep within the helix and gradually fade away towards its interior. By studying picosecond-nanosecond dynamics in short DNA dodecamers with variable length A-tracts, we discover that A-tracts are relatively rigid and can modulate the flexibility of their junctions in a length-dependent manner. We identify the presence of large-amplitude deoxyribose internal motions in CA/TG and CG steps placed in different sequences that likely represent rapid sugar repuckering. Moreover, by using NMR relaxation dispersion in concert with steered molecular dynamics simulations, we observe transient sequence-specific excursions away from Watson-Crick base-pairing at CA/TG and TA steps inside DNA dodecamers towards low-populated and short-lived A•T and G•C Hoogsteen base pairs. We show that their populations and lifetimes can be modulated by environmental factors like acidity, monovalent and divalent ions as well as intrinsic sequence and chemical modifications. The observation of Hoogsteen base pairs in duplexes specifically bound to transcription factors and in damaged sites implies that the DNA double helix intrinsically codes for excited state Hoogsteen base pairs as a means of expanding its structural complexity beyond Watson-Crick base-pairing. The methods presented here provide a new route for characterizing transient nucleic acid structures, which we predict will be abundant in the genome and constitute a second transient layer of the genetic code. Advisors/Committee Members: Al-Hashimi, Hashim M. (committee member), Fierke, Carol (committee member), O'Brien, Patrick (committee member), Walter, Nils G. (committee member).

Subjects/Keywords: DNA Dynamics; NMR Spectroscopy; Hoogsteen Base Pair; Relaxation Dispersion; A-tract DNA; Biological Chemistry; Science

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Nikolova, E. N. (2011). The Double Helix in Motion: New Insights into Sequence-specific, Functional DNA Dynamics Using NMR Spectroscopy. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/89648

Chicago Manual of Style (16^th Edition):

Nikolova, Evgenia Nikolaevna. “The Double Helix in Motion: New Insights into Sequence-specific, Functional DNA Dynamics Using NMR Spectroscopy.” 2011. Doctoral Dissertation, University of Michigan. Accessed January 26, 2021. http://hdl.handle.net/2027.42/89648.

MLA Handbook (7^th Edition):

Nikolova, Evgenia Nikolaevna. “The Double Helix in Motion: New Insights into Sequence-specific, Functional DNA Dynamics Using NMR Spectroscopy.” 2011. Web. 26 Jan 2021.

Vancouver:

Nikolova EN. The Double Helix in Motion: New Insights into Sequence-specific, Functional DNA Dynamics Using NMR Spectroscopy. [Internet] [Doctoral dissertation]. University of Michigan; 2011. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/2027.42/89648.

Council of Science Editors:

Nikolova EN. The Double Helix in Motion: New Insights into Sequence-specific, Functional DNA Dynamics Using NMR Spectroscopy. [Doctoral Dissertation]. University of Michigan; 2011. Available from: http://hdl.handle.net/2027.42/89648

Bucknell University

18. Cecchini, Michael R. Vibrational Relaxation of 13CO2(v2) by Atomic Oxygen.

Degree: 2012, Bucknell University

URL: https://digitalcommons.bucknell.edu/masters_theses/90

► Carbon dioxide (CO2) has been of recent interest due to the issue of greenhouse cooling in the upper atmosphere by species such as CO2 and… (more)

Subjects/Keywords: Vibrational Relaxation; Carbon Dioxide Isotope; Troposphere; Mesosphere; Atmospheric Cooling; TDLAS; Quenching; Chemistry

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APA (6^th Edition):

Cecchini, M. R. (2012). Vibrational Relaxation of 13CO2(v2) by Atomic Oxygen. (Thesis). Bucknell University. Retrieved from https://digitalcommons.bucknell.edu/masters_theses/90

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Cecchini, Michael R. “Vibrational Relaxation of 13CO2(v2) by Atomic Oxygen.” 2012. Thesis, Bucknell University. Accessed January 26, 2021. https://digitalcommons.bucknell.edu/masters_theses/90.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Cecchini, Michael R. “Vibrational Relaxation of 13CO2(v2) by Atomic Oxygen.” 2012. Web. 26 Jan 2021.

Vancouver:

Cecchini MR. Vibrational Relaxation of 13CO2(v2) by Atomic Oxygen. [Internet] [Thesis]. Bucknell University; 2012. [cited 2021 Jan 26]. Available from: https://digitalcommons.bucknell.edu/masters_theses/90.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Cecchini MR. Vibrational Relaxation of 13CO2(v2) by Atomic Oxygen. [Thesis]. Bucknell University; 2012. Available from: https://digitalcommons.bucknell.edu/masters_theses/90

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Iowa State University

19. Hu, Yanyan. Solid state NMR method development and studies of biological and biomimetic nanocomposites.

Degree: 2011, Iowa State University

URL: https://lib.dr.iastate.edu/etd/11198

► This thesis describes application and development of advanced solid-state nuclear magnetic resonance techniques for complex materials, in particular organic-inorganic nanocomposites and thermoelectric tellurides. The apatite-collagen… (more)

▼ This thesis describes application and development of advanced solid-state nuclear magnetic resonance techniques for complex materials, in particular organic-inorganic nanocomposites and thermoelectric tellurides. The apatite-collagen interface, essential for understanding the biomineralization process in bone and engineering the interface for controlled bio-mimetic synthesis and optimized mechanical properties, is buried within the nanocomposite of bone. We used multinuclear solid-state NMR to study the composition and structure of the interface. Citrate has been identified as the main organic molecule strongly bound to the apatite surface with a density of 1/(2 nm)2, covering 1/6 of the total surface area in bovine bone. Citrate provides more carboxylate groups, one of the key functional groups found to affect apatite nucleation and growth, than all the non-collagenous proteins all together in bone; thus we propose that citrate stabilizes apatite crystals at a very small thickness of ∼3 nm (4 unit cells) to increase bone fracture tolerance. The hypothesis has been confirmed in vitro by adding citrate in the bio-mimetic synthesis of polymer-hydroxyapatite nanocomposites. The results have shown that the size of hydroxyapatite nanocrystals decreases as increasing citrate concentration. With citrate concentrations comparable to that in body fluids, similar-sized nanocrystals as in bone have been produced. Besides the dimensions of the apatite crystals, the composition of bone also affects its bio-functional and macroscopic mechanical properties; therefore, our team also extended its effort to enhance the inorganic portion in our bio-mimetic synthesis from originally 15 wt% to current 50 wt% compared to 65 wt% in bovine bone, by using Lysine-Leucine hydroxyapatite nucleating diblock co-polypeptide, which forms a gel at very low concentration. In this thesis, various advanced solid state NMR techniques have been employed to characterize nanocomposites. Meanwhile, we have developed new methods to achieve broadband high resolution NMR and improve the accuracy of inter-nuclear distance measurements involving quadrupolar spins. Broadband high resolution NMR of spin-1/2 nuclei has been accomplished by the adaptation of the magic angle turning (MAT) method to fast magic angle spinning, termed fast MAT, by solving technical problems such as off-resonance effects. Fast MAT separates chemical shift anisotropy and isotropic chemical shifts over a spectral range of ∼1.8 γB1 without significant distortions. Fast MAT 125Te NMR has been applied to study technologically important telluride materials with spectra spreading up to 190 kHz. The signal-to-noise ratio of the spectra is significantly improved by using echo-matched Gaussian filtering in offline data processing. The accuracy of the measured distances between spin-1/2 and quadrupolar nuclei with methods such as SPIDER and REAPDOR has been improved by compensating for the fast longitudinal quadrupolar relaxation on the sub-millisecond with a modified S0 pulse sequence. Also, the…

Subjects/Keywords: bone; citrate; fast magic angle turning; fast quadrupolar relaxation; nanocomposites; Solid state NMR; Chemistry

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APA (6^th Edition):

Hu, Y. (2011). Solid state NMR method development and studies of biological and biomimetic nanocomposites. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/11198

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Hu, Yanyan. “Solid state NMR method development and studies of biological and biomimetic nanocomposites.” 2011. Thesis, Iowa State University. Accessed January 26, 2021. https://lib.dr.iastate.edu/etd/11198.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Hu, Yanyan. “Solid state NMR method development and studies of biological and biomimetic nanocomposites.” 2011. Web. 26 Jan 2021.

Vancouver:

Hu Y. Solid state NMR method development and studies of biological and biomimetic nanocomposites. [Internet] [Thesis]. Iowa State University; 2011. [cited 2021 Jan 26]. Available from: https://lib.dr.iastate.edu/etd/11198.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Hu Y. Solid state NMR method development and studies of biological and biomimetic nanocomposites. [Thesis]. Iowa State University; 2011. Available from: https://lib.dr.iastate.edu/etd/11198

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

20. Meyer, Virginia. Applications of EPR with an Emphasis on Tau Fibril Structure.

Degree: PhD, Chemistry and Biochemistry, 2014, U of Denver

URL: https://digitalcommons.du.edu/etd/988

► Substances containing unpaired electrons have been studied by electron paramagnetic resonance (EPR) for nearly 70 years. With continual development and enhancement of EPR techniques,… (more)

▼ Substances containing unpaired electrons have been studied by electron paramagnetic resonance (EPR) for nearly 70 years. With continual development and enhancement of EPR techniques, questions have arisen regarding optimum method selection for a given sample based on its properties. In this work, radiation defects, natural lattice defects, solid organic radicals, radicals in solution, and spin-labeled proteins were analyzed using CW, pulse, and rapid scan EPR to compare methods. Studies of solid BDPA, E' in quartz, N_s⁰ in diamond, and a-Si:H, showed that rapid scan could overcome many obstacles presented by other techniques, cementing rapid scan as an effective alternative to CW and pulse methods. Relaxation times of six nitroxide radicals were characterized from 0.25-34 GHz, guiding synthesis of improved nitroxides for in vivo imaging experiments. Processes contributing to T₁ of DPPH in polystyrene were found through variable temperature measurements at X- and Q-band, resolving previously-reported discrepancies in relaxation properties and providing new insight into this commonly-used standard. In the history of EPR, the study of proteins is relatively new. Double electron-electron resonance (DEER) has emerged as a powerful technique for the study of amyloid fibrils, a class of protein aggregates implicated in a number of neurodegenerative disorders. Microtubule-associated protein tau forms fibrils linked to Alzheimerfs disease through seeded conversion of monomer. Self-assembly is mediated by the microtubule binding repeats in tau, and there are either three or four repeats present depending on the isoform. DEER was used to show that filaments of 3R and 4R tau are conformationally distinct and that 4R fibrils adopt a heterogeneous mixture of conformations. Populations of 4R fibril conformations, which were independently validated using a model system, can be modulated by introduction of mutations to the primary sequence or by varying fibril growth conditions. These findings provided unprecedented insights into the seed selection of tau monomers and established conformational compatibility as an important driving force in tau fibril propagation. Lastly, DEER acquisition was improved through addition of paramagnetic metal to spin-labeled protein, decreasing collection time, and through use of a novel spin label with increased T₂, thereby lengthening the available acquisition window. Advisors/Committee Members: Martin Margittai, Ph.D..

Subjects/Keywords: Double electron-electron resonance; DEER; Electron paramagnetic resonance; Relaxation time; Tau; Biochemistry; Chemistry

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APA (6^th Edition):

Meyer, V. (2014). Applications of EPR with an Emphasis on Tau Fibril Structure. (Doctoral Dissertation). U of Denver. Retrieved from https://digitalcommons.du.edu/etd/988

Chicago Manual of Style (16^th Edition):

Meyer, Virginia. “Applications of EPR with an Emphasis on Tau Fibril Structure.” 2014. Doctoral Dissertation, U of Denver. Accessed January 26, 2021. https://digitalcommons.du.edu/etd/988.

MLA Handbook (7^th Edition):

Meyer, Virginia. “Applications of EPR with an Emphasis on Tau Fibril Structure.” 2014. Web. 26 Jan 2021.

Vancouver:

Meyer V. Applications of EPR with an Emphasis on Tau Fibril Structure. [Internet] [Doctoral dissertation]. U of Denver; 2014. [cited 2021 Jan 26]. Available from: https://digitalcommons.du.edu/etd/988.

Council of Science Editors:

Meyer V. Applications of EPR with an Emphasis on Tau Fibril Structure. [Doctoral Dissertation]. U of Denver; 2014. Available from: https://digitalcommons.du.edu/etd/988

University of Akron

21. LIU, JIANNING. Understand the mechanical behaviors of polymer glasses under extension and compression.

Degree: PhD, Polymer Science, 2018, University of Akron

URL: http://rave.ohiolink.edu/etdc/view?acc_num=akron1542042896236543

► It is of great fundamental important and practical interest to understand what controls the mechanical properties of polymeric glasses, such as shear yielding, necking, crazing,… (more)

▼ It is of great fundamental important and practical interest to understand what controls the mechanical properties of polymeric glasses, such as shear yielding, necking, crazing, strain hardening and the brittle-ductile transition. Despite the tremendous efforts in the past decades to explorer the mechanical instabilities of polymer glasses, many topics about the nature of glass transition, nature of stress remain vague and under extensive debates. In this dissertation, we carried out a series of mechanical tests to study the mechanical response of polymeric glasses in both uniaxial extension and compression. Based on our recent phenomenological molecular model, this work investigates the origin of mechanical stress based on stress relaxation and brittle-ductile transition experiments of polymer glasses. Different from previous models emphasizing the inter-segmental contribution in stress, our stress relaxation experimental results revealed the important role of chain network by intra-chain connectivity and chain uncrossability. In Capture III, in room temperature stress relaxation experiments, we studied the stress relaxation behaviors of four different commercial polymer glasses under both extension and compression large ductile deformation over a wide range of rate. It was found that the initial stress relaxation rate after holding post-yield deformation is linearly proportional to the rate of prior deformation. While the pre-yield stress relaxation is logarithmically slow. This rate rescaling behaviors indicates the surviving segmental mobility in absence of ongoing deformation was due to the yield induced activation process. In Capture IV, to elucidate the nature of stress during deformation and stress relaxation, temperature for stress relaxation was increased to near Tg. All the pre-yield stress would vanish within fast segmental relaxation time independent of rate, while the initial post-yield stress relaxation can be either faster or far slower than the segmental dynamics dependents on prior deformation rate. Residual stress after large post-yield relaxation was observed to retain significant levels on the time scale much longer than the time scale for all the rate range investigated near Tg. Supporting results by MD simulation shown the chain network is essential in the mechanical response of uniaxial compression of glassy polymers through the chain network’s lateral resistance to the lateral expansion and contribute to compressive stress. In Capture V and VI, to understand the role of chain network under uniaxial compression, we systematically studied how the structural change of chain network dictates whether the uniaxial compression of polymer glasses is ductile or suffers brittle fracture. Those structural characteristics of the perceived chain network can be changed by variation of molecular weight, molecular composition, and anisotropic reconstruction through melt stretching. Advisors/Committee Members: Wang, Shi-Qing (Advisor), Miyoshi, Toshikazu (Committee Chair).

Subjects/Keywords: Materials Science; Polymer Chemistry; Polymers; polymer glasses; rheology; stress relaxation; brittle-to-ductile transition

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APA (6^th Edition):

LIU, J. (2018). Understand the mechanical behaviors of polymer glasses under extension and compression. (Doctoral Dissertation). University of Akron. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=akron1542042896236543

Chicago Manual of Style (16^th Edition):

LIU, JIANNING. “Understand the mechanical behaviors of polymer glasses under extension and compression.” 2018. Doctoral Dissertation, University of Akron. Accessed January 26, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron1542042896236543.

MLA Handbook (7^th Edition):

LIU, JIANNING. “Understand the mechanical behaviors of polymer glasses under extension and compression.” 2018. Web. 26 Jan 2021.

Vancouver:

LIU J. Understand the mechanical behaviors of polymer glasses under extension and compression. [Internet] [Doctoral dissertation]. University of Akron; 2018. [cited 2021 Jan 26]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=akron1542042896236543.

Council of Science Editors:

LIU J. Understand the mechanical behaviors of polymer glasses under extension and compression. [Doctoral Dissertation]. University of Akron; 2018. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=akron1542042896236543

Simon Fraser University

22. Gao, Jialiang. Relaxation processes in tertiary-butyl-phthalocyanine in Shpol'skii matrices at low temperatures.

Degree: 1992, Simon Fraser University

URL: http://summit.sfu.ca/item/3702

Subjects/Keywords: Spin-lattice relaxation.; Relaxation phenomena.; Nuclear magnetic resonance.; Excited state chemistry.; Porphyrins.; Phthalocyanines.

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APA (6^th Edition):

Gao, J. (1992). Relaxation processes in tertiary-butyl-phthalocyanine in Shpol'skii matrices at low temperatures. (Thesis). Simon Fraser University. Retrieved from http://summit.sfu.ca/item/3702

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Gao, Jialiang. “Relaxation processes in tertiary-butyl-phthalocyanine in Shpol'skii matrices at low temperatures.” 1992. Thesis, Simon Fraser University. Accessed January 26, 2021. http://summit.sfu.ca/item/3702.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Gao, Jialiang. “Relaxation processes in tertiary-butyl-phthalocyanine in Shpol'skii matrices at low temperatures.” 1992. Web. 26 Jan 2021.

Vancouver:

Gao J. Relaxation processes in tertiary-butyl-phthalocyanine in Shpol'skii matrices at low temperatures. [Internet] [Thesis]. Simon Fraser University; 1992. [cited 2021 Jan 26]. Available from: http://summit.sfu.ca/item/3702.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Gao J. Relaxation processes in tertiary-butyl-phthalocyanine in Shpol'skii matrices at low temperatures. [Thesis]. Simon Fraser University; 1992. Available from: http://summit.sfu.ca/item/3702

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Utah

23. Payne, Adam. Concept for room temperature single-spin tunneling force microscopy with atomic spatial resolution.

Degree: PhD, Physics & Astronomy, 2015, University of Utah

URL: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3995/rec/537

► A study of a force detected single-spin magnetic resonance measurement concept with atomic spatial resolution is presented. The method is based upon electrostatic force detection… (more)

Subjects/Keywords: Composition; segregation; defects and impurities; Electron paramagnetic resonance and relaxation; Quantum information; Scanning tunneling microscopy (including chemistry induced with STM)

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APA (6^th Edition):

Payne, A. (2015). Concept for room temperature single-spin tunneling force microscopy with atomic spatial resolution. (Doctoral Dissertation). University of Utah. Retrieved from http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3995/rec/537

Chicago Manual of Style (16^th Edition):

Payne, Adam. “Concept for room temperature single-spin tunneling force microscopy with atomic spatial resolution.” 2015. Doctoral Dissertation, University of Utah. Accessed January 26, 2021. http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3995/rec/537.

MLA Handbook (7^th Edition):

Payne, Adam. “Concept for room temperature single-spin tunneling force microscopy with atomic spatial resolution.” 2015. Web. 26 Jan 2021.

Vancouver:

Payne A. Concept for room temperature single-spin tunneling force microscopy with atomic spatial resolution. [Internet] [Doctoral dissertation]. University of Utah; 2015. [cited 2021 Jan 26]. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3995/rec/537.

Council of Science Editors:

Payne A. Concept for room temperature single-spin tunneling force microscopy with atomic spatial resolution. [Doctoral Dissertation]. University of Utah; 2015. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3995/rec/537

University of California – Berkeley

24. Jiang, Chang-Ming. Charge Carrier Dynamics in Transition Metal Oxides Studied by Femtosecond Transient Extreme Ultraviolet Absorption Spectroscopy.

Degree: Chemistry, 2015, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/7129618s

► With the ability to disentangle electronic transitions that occur on different elements and local electronic structures, time-resolved extreme ultraviolet (XUV) spectroscopy has emerged as a… (more)

Subjects/Keywords: Physical chemistry; Materials Science; Carrier relaxation; Extreme ultraviolet; High harmonic generation; Transient absorption; Transition metal oxides

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APA (6^th Edition):

Jiang, C. (2015). Charge Carrier Dynamics in Transition Metal Oxides Studied by Femtosecond Transient Extreme Ultraviolet Absorption Spectroscopy. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/7129618s

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Jiang, Chang-Ming. “Charge Carrier Dynamics in Transition Metal Oxides Studied by Femtosecond Transient Extreme Ultraviolet Absorption Spectroscopy.” 2015. Thesis, University of California – Berkeley. Accessed January 26, 2021. http://www.escholarship.org/uc/item/7129618s.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Jiang, Chang-Ming. “Charge Carrier Dynamics in Transition Metal Oxides Studied by Femtosecond Transient Extreme Ultraviolet Absorption Spectroscopy.” 2015. Web. 26 Jan 2021.

Vancouver:

Jiang C. Charge Carrier Dynamics in Transition Metal Oxides Studied by Femtosecond Transient Extreme Ultraviolet Absorption Spectroscopy. [Internet] [Thesis]. University of California – Berkeley; 2015. [cited 2021 Jan 26]. Available from: http://www.escholarship.org/uc/item/7129618s.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Jiang C. Charge Carrier Dynamics in Transition Metal Oxides Studied by Femtosecond Transient Extreme Ultraviolet Absorption Spectroscopy. [Thesis]. University of California – Berkeley; 2015. Available from: http://www.escholarship.org/uc/item/7129618s

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – Berkeley

25. Harman, William Hill. Metal-Pyrrolide Complexes in Three-fold Symmetry: Synthesis, Structure, Reactivity and Magnetism.

Degree: Chemistry, 2010, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/8q2217f3

► Given the prominence of six-coordinate pseudo-octahedral complexes in transition metal chemistry, lower coordinate complexes in tetrahedral, trigonal pyramidal and trigonal bipyramidal configurations have garnered increased… (more)

▼ Given the prominence of six-coordinate pseudo-octahedral complexes in transition metal chemistry, lower coordinate complexes in tetrahedral, trigonal pyramidal and trigonal bipyramidal configurations have garnered increased interest due to the changes in electronic structure and reactivity resultant from three-fold symmetry relative to the four-fold symmetry commonly observed in their pseudo-octahedral counterparts. Herein, we report a range of such effects in a collection of transition metal complexes supported by chelating, trianionic trispyrrolide ligands [tpaR]3-. In chapter one, two trigonal pyramidal iron(II) complexes, [(tpaPh)Fe]- and [(tpaMes)Fe]-, are discussed which are capable of undergoing oxygen atom transfer reactions and subsequent activation of strong C-H bonds. Additionally, the mesityl derivative is capable of oxygen atom transfer from nitrous oxide, an attractive but notoriously unreactive molecule. In chapter two, this family of iron(II) complexes is expanded to include tert-butyl, 2,4,6-triisopropylphenyl and 2,6-difluorophenyl substituted variants, and the magnetic properties of this homologous series of trigonal pyramidal iron(II) complexes are explored. Notably, a number of these complexes exhibit frequency dependent signals at low temperature in the imaginary component of ac magnetic susceptibility measurements performed in the presence of a small applied field. Further exploration of this behavior via magnetometry, high-field EPR and Mössbauer spectroscopy reveal a large barrier to magnetic relaxation in these complexes, in some cases comparable to the best known single molecule magnets. This phenomenon is accounted for by the unquenched orbital angular momentum present in a three-fold symmetric high spin d6 system, leading to significant uniaxial anisotropy and a barrier to spin inversion. Progress towards a magneto-structural analysis of this behavior is made for this series. Chapter three contains a through treatment of the coordination, redox and group transfer chemistry of the iron(II) platform [(tpaMes)Fe]-. In particular, it is shown that this complex is capable of supporting both high and low spin five coordinate adducts, including a rare example of a paramagnetic carbonyl complex of iron(II), [(tpaMes)Fe(CO)]-. Furthermore, the redox chemistry of this system is illustrated in the synthesis of the neutral iron(III) complex (tpaMes)Fe(i-PrNH2). As an extensiont to the oxygen atom chemistry presented in chapter one, nitrene group transfer to [(tpaMes)Fe]- is described, resulting in the synthesis of an iron(III) amido complex. The identity of this species is confirmed by high resolution electrospray mass spectrometry as well as Mössbauer, x-ray absorption and EPR spectroscopies. In chapter four, the vanadium chemistry of [tpaR]3- is introduced. In particular, the vanadium(III) complex (tpaMes)V(THF) is show to react with an aryl azide to yield an isolable vanadium(V) diazenylimido species, a member of a very rare structural type. This complex is shown to decompose unimolecularly by…

Subjects/Keywords: Inorganic chemistry; Metal-Ligand Multiple Bonding; Metal-Pyrrolide Complexes; Nitrous Oxide Activation; Slow Magnetic Relaxation; Three-fold Symmetry

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APA (6^th Edition):

Harman, W. H. (2010). Metal-Pyrrolide Complexes in Three-fold Symmetry: Synthesis, Structure, Reactivity and Magnetism. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/8q2217f3

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Harman, William Hill. “Metal-Pyrrolide Complexes in Three-fold Symmetry: Synthesis, Structure, Reactivity and Magnetism.” 2010. Thesis, University of California – Berkeley. Accessed January 26, 2021. http://www.escholarship.org/uc/item/8q2217f3.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Harman, William Hill. “Metal-Pyrrolide Complexes in Three-fold Symmetry: Synthesis, Structure, Reactivity and Magnetism.” 2010. Web. 26 Jan 2021.

Vancouver:

Harman WH. Metal-Pyrrolide Complexes in Three-fold Symmetry: Synthesis, Structure, Reactivity and Magnetism. [Internet] [Thesis]. University of California – Berkeley; 2010. [cited 2021 Jan 26]. Available from: http://www.escholarship.org/uc/item/8q2217f3.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Harman WH. Metal-Pyrrolide Complexes in Three-fold Symmetry: Synthesis, Structure, Reactivity and Magnetism. [Thesis]. University of California – Berkeley; 2010. Available from: http://www.escholarship.org/uc/item/8q2217f3

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of California – Berkeley

26. Chen, Joseph Jung-Wen. Magnetic Resonance Investigations of Adsorbate Dynamics in Metal-Organic Frameworks.

Degree: Chemical Engineering, 2014, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/2818b16w

► Metal-organic frameworks (MOFs), a new class of porous materials, are crystalline networks of metal clusters or ions connected by organic linkers through coordination bonds. These… (more)

Subjects/Keywords: Chemical engineering; Nanoscience; Physical chemistry; condensation; diffusion; metal-organic frameworks; nuclear magnetic resonance; porous materials; relaxation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Chen, J. J. (2014). Magnetic Resonance Investigations of Adsorbate Dynamics in Metal-Organic Frameworks. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/2818b16w

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Chen, Joseph Jung-Wen. “Magnetic Resonance Investigations of Adsorbate Dynamics in Metal-Organic Frameworks.” 2014. Thesis, University of California – Berkeley. Accessed January 26, 2021. http://www.escholarship.org/uc/item/2818b16w.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Chen, Joseph Jung-Wen. “Magnetic Resonance Investigations of Adsorbate Dynamics in Metal-Organic Frameworks.” 2014. Web. 26 Jan 2021.

Vancouver:

Chen JJ. Magnetic Resonance Investigations of Adsorbate Dynamics in Metal-Organic Frameworks. [Internet] [Thesis]. University of California – Berkeley; 2014. [cited 2021 Jan 26]. Available from: http://www.escholarship.org/uc/item/2818b16w.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Chen JJ. Magnetic Resonance Investigations of Adsorbate Dynamics in Metal-Organic Frameworks. [Thesis]. University of California – Berkeley; 2014. Available from: http://www.escholarship.org/uc/item/2818b16w

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Alabama

27. Vennam, Preethi Reddy. Electron paramagnetic resonance investigation of semiquinone intermediate in mitochondrial cytochrome bc1 complex.

Degree: 2012, University of Alabama

URL: http://purl.lib.ua.edu/81395

► The Rieske/cytochrome b complexes, also known as cytochrome bc complexes, catalyze a unique oxidant-induced reduction reaction at their quinol oxidase (Qo) sites, in which substrate… (more)

▼ The Rieske/cytochrome b complexes, also known as cytochrome bc complexes, catalyze a unique oxidant-induced reduction reaction at their quinol oxidase (Qo) sites, in which substrate hydroquinone reduces two distinct electron transfer chains, one leading to a series of high-potential electron carriers, the second to low-potential cytochrome b. This reaction is a critical step in energy storage by the Q-cycle. The semiquinone intermediate in this reaction can also reduce O2 to produce deleterious superoxide. It is yet unknown how the enzyme controls this reaction, though numerous models have been proposed. In previous work we were able to trap a Q-cycle semiquinone anion intermediate, termed SQo in bacterial cyt bc1 by rapid freeze-quenching. In this work, we apply pulsed EPR techniques to determine the location of SQo in mictochondrial complex and that mitochondrial SQo has highly unusual properties. In contrast with previous semiquinone intermediates, SQo is not thermodynamically stabilized, or even destabilized with respect to solution. It is localized in the Qo pocket at a niche, which is distinct from previously described inhibitor-binding sites, but is sufficiently close to cytochrome bL to allow rapid electron transfer. Both the location of the binding sites and EPR analysis show that SQo is not stabilized by hydrogen bonds to proteins. These results indicate that the formation of SQo involves "stripping" of both substrate protons during the initial oxidation to the high potential chain, as well as conformational changes of both semiquinone species and Qo site proteins components. The resulting charged radical is kinetically trapped, rather than thermodynamically stabilized (as in most enzymatic semiquinone species), maintaining redox energy to drive electron transfer to cytochrome bL, while minimizing certain Q-cycle bypass reactions including oxidation of pre-reduced cytochrome b and reduction of O2. (Published By University of Alabama Libraries) Advisors/Committee Members: Bowman, Michael K., Street, Shane, Cassady, Carolyn J., Busenlehner, Laura, Kramer, David M., University of Alabama. Dept. of Chemistry.

Subjects/Keywords: Electronic Thesis or Dissertation; – thesis; Chemistry; cytochrome bc1; Electron Paramagnetic Resonance; Paramagnetic relaxation enhancement; Q-cycle; Quinone; Rieske iron sulfur protein

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Vennam, P. R. (2012). Electron paramagnetic resonance investigation of semiquinone intermediate in mitochondrial cytochrome bc1 complex. (Thesis). University of Alabama. Retrieved from http://purl.lib.ua.edu/81395

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Vennam, Preethi Reddy. “Electron paramagnetic resonance investigation of semiquinone intermediate in mitochondrial cytochrome bc1 complex.” 2012. Thesis, University of Alabama. Accessed January 26, 2021. http://purl.lib.ua.edu/81395.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Vennam, Preethi Reddy. “Electron paramagnetic resonance investigation of semiquinone intermediate in mitochondrial cytochrome bc1 complex.” 2012. Web. 26 Jan 2021.

Vancouver:

Vennam PR. Electron paramagnetic resonance investigation of semiquinone intermediate in mitochondrial cytochrome bc1 complex. [Internet] [Thesis]. University of Alabama; 2012. [cited 2021 Jan 26]. Available from: http://purl.lib.ua.edu/81395.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Vennam PR. Electron paramagnetic resonance investigation of semiquinone intermediate in mitochondrial cytochrome bc1 complex. [Thesis]. University of Alabama; 2012. Available from: http://purl.lib.ua.edu/81395

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Oxford

28. Stelzl, Lukas Sebastian. Studying marcomolecular transitions by NMR and computer simulations.

Degree: PhD, 2014, University of Oxford

URL: http://ora.ox.ac.uk/objects/uuid:6e4bbe06-fc58-471b-a932-d940fe78b9a5 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.640075

► Macromolecular transitions such as conformational changes and protein-protein association underlie many biological processes. Conformational changes in the N-terminal domain of the transmembrane protein DsbD (nDsbD)… (more)

▼ Macromolecular transitions such as conformational changes and protein-protein association underlie many biological processes. Conformational changes in the N-terminal domain of the transmembrane protein DsbD (nDsbD) were studied by NMR and molecular dynamics (MD) simulations. nDsbD supplies reductant to biosynthetic pathways in the oxidising periplasm of Gram-negative bacteria after receiving reductant from the C-terminal domain of DsbD (cDsbD). Reductant transfer in the DsbD pathway happens via protein-protein association and subsequent thiol-disulphide exchange reactions. The cap loop shields the active-site cysteines in nDsbD from non-cognate oxidation, but needs to open when nDsbD bind its interaction partners. The loop was rigid in MD simulations of reduced nDsbD. More complicated dynamics were observed for oxidised nDsbD, as the disulphide bond introduces frustration which led to loop opening in some trajectories. The simulations of oxidised and reduced nDsbD agreed well with previous NMR spin-relaxation and residual dipolar coupling measurements as well as chemical shift-based torsion angle predictions. NMR relaxation dispersion experiments revealed that the cap loop of oxidised nDsbD exchanges between a major and a minor conformation. The differences in their conformational dynamics may explain why oxidised nDsbD binds its physiological partner cDsbD much tighter than reduced nDsbD. The redox-state dependent interaction between cDsbD and nDsbD is thought to enhance turnover. NMR relaxation dispersion experiments gave insight into the kinetics of the redox-state dependent interaction. MD simulations identified dynamic encounter complexes in the association of nDsbD with cDsbD. The mechanism of the conformational changes in the transport cycle of LacY were also investigated. LacY switches between periplasmic open and cytoplasmic open conformations to transport sugars across the cell membrane. Two mechanisms have been proposed for the conformational change, a rocker-switch mechanism based on rigid body motions and an “airlock” like mechanism in which the transporter would switch conformation via a fully occluded structure. In MD simulations using the novel dynamics importance sampling approach such a fully occluded structure was found. The simulations argued against a strict “rocker-switch” mechanism.

Subjects/Keywords: 572; Biophysical chemistry; Biophysics; NMR spectroscopy; Molecular biophysics (biochemistry); Computational biochemistry; MD simulations; NMR spin-relaxation; NMR dynamics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Stelzl, L. S. (2014). Studying marcomolecular transitions by NMR and computer simulations. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:6e4bbe06-fc58-471b-a932-d940fe78b9a5 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.640075

Chicago Manual of Style (16^th Edition):

Stelzl, Lukas Sebastian. “Studying marcomolecular transitions by NMR and computer simulations.” 2014. Doctoral Dissertation, University of Oxford. Accessed January 26, 2021. http://ora.ox.ac.uk/objects/uuid:6e4bbe06-fc58-471b-a932-d940fe78b9a5 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.640075.

MLA Handbook (7^th Edition):

Stelzl, Lukas Sebastian. “Studying marcomolecular transitions by NMR and computer simulations.” 2014. Web. 26 Jan 2021.

Vancouver:

Stelzl LS. Studying marcomolecular transitions by NMR and computer simulations. [Internet] [Doctoral dissertation]. University of Oxford; 2014. [cited 2021 Jan 26]. Available from: http://ora.ox.ac.uk/objects/uuid:6e4bbe06-fc58-471b-a932-d940fe78b9a5 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.640075.

Council of Science Editors:

Stelzl LS. Studying marcomolecular transitions by NMR and computer simulations. [Doctoral Dissertation]. University of Oxford; 2014. Available from: http://ora.ox.ac.uk/objects/uuid:6e4bbe06-fc58-471b-a932-d940fe78b9a5 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.640075

Washington University in St. Louis

29. Alaniva, Nicholas Howard. Instrumentation for Dynamic Nuclear Polarization and Application of Electron Decoupling for Electron Relaxation Measurement.

Degree: PhD, Chemistry, 2019, Washington University in St. Louis

URL: https://openscholarship.wustl.edu/art_sci_etds/1989

► Dynamic nuclear polarization nuclear magnetic resonance (DNP NMR) exploits internal electron spin and nuclear spin interactions to increase sensitivity and uncover valuable information regarding structure… (more)

Subjects/Keywords: Dynamic Nuclear Polarization, Electron Decoupling, Electron Relaxation, Magic-Angle Spinning, Nuclear Magnetic Resonance; Electromagnetics and Photonics; Physical Chemistry

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Alaniva, N. H. (2019). Instrumentation for Dynamic Nuclear Polarization and Application of Electron Decoupling for Electron Relaxation Measurement. (Doctoral Dissertation). Washington University in St. Louis. Retrieved from https://openscholarship.wustl.edu/art_sci_etds/1989

Chicago Manual of Style (16^th Edition):

Alaniva, Nicholas Howard. “Instrumentation for Dynamic Nuclear Polarization and Application of Electron Decoupling for Electron Relaxation Measurement.” 2019. Doctoral Dissertation, Washington University in St. Louis. Accessed January 26, 2021. https://openscholarship.wustl.edu/art_sci_etds/1989.

MLA Handbook (7^th Edition):

Alaniva, Nicholas Howard. “Instrumentation for Dynamic Nuclear Polarization and Application of Electron Decoupling for Electron Relaxation Measurement.” 2019. Web. 26 Jan 2021.

Vancouver:

Alaniva NH. Instrumentation for Dynamic Nuclear Polarization and Application of Electron Decoupling for Electron Relaxation Measurement. [Internet] [Doctoral dissertation]. Washington University in St. Louis; 2019. [cited 2021 Jan 26]. Available from: https://openscholarship.wustl.edu/art_sci_etds/1989.

Council of Science Editors:

Alaniva NH. Instrumentation for Dynamic Nuclear Polarization and Application of Electron Decoupling for Electron Relaxation Measurement. [Doctoral Dissertation]. Washington University in St. Louis; 2019. Available from: https://openscholarship.wustl.edu/art_sci_etds/1989

University of Kansas

30. Schieber, Loren J. Methods for Increasing Sensitivity and Throughput of Solid-State NMR Spectroscopy of Pharmaceutical Solids.

Degree: PhD, Pharmaceutical Chemistry, 2010, University of Kansas

URL: http://hdl.handle.net/1808/6279

► Solid-state nuclear magnetic resonance (SSNMR) spectroscopy has been demonstrated to be a powerful technique for investigating solid dosage formulations. SSNMR has the ability to determine… (more)

Subjects/Keywords: Pharmaceutical chemistry; Amorphous; Fluorine; Nmr; Oxygen; Relaxation; Solid-state

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Schieber, L. J. (2010). Methods for Increasing Sensitivity and Throughput of Solid-State NMR Spectroscopy of Pharmaceutical Solids. (Doctoral Dissertation). University of Kansas. Retrieved from http://hdl.handle.net/1808/6279

Chicago Manual of Style (16^th Edition):

Schieber, Loren J. “Methods for Increasing Sensitivity and Throughput of Solid-State NMR Spectroscopy of Pharmaceutical Solids.” 2010. Doctoral Dissertation, University of Kansas. Accessed January 26, 2021. http://hdl.handle.net/1808/6279.

MLA Handbook (7^th Edition):

Schieber, Loren J. “Methods for Increasing Sensitivity and Throughput of Solid-State NMR Spectroscopy of Pharmaceutical Solids.” 2010. Web. 26 Jan 2021.

Vancouver:

Schieber LJ. Methods for Increasing Sensitivity and Throughput of Solid-State NMR Spectroscopy of Pharmaceutical Solids. [Internet] [Doctoral dissertation]. University of Kansas; 2010. [cited 2021 Jan 26]. Available from: http://hdl.handle.net/1808/6279.

Council of Science Editors:

Schieber LJ. Methods for Increasing Sensitivity and Throughput of Solid-State NMR Spectroscopy of Pharmaceutical Solids. [Doctoral Dissertation]. University of Kansas; 2010. Available from: http://hdl.handle.net/1808/6279

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