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Ribosome Recycling Step In Yeast Cytoplasmic Protein Synthesis Is Catalyzed By Eef3 And Atp, Sarah F. Mitchell Jan 2010

Ribosome Recycling Step In Yeast Cytoplasmic Protein Synthesis Is Catalyzed By Eef3 And Atp, Sarah F. Mitchell

Chemistry and Biochemistry Faculty Works

After each round of protein biosynthesis, the posttermination complex (PoTC) consisting of a ribosome, mRNA, and tRNA must be disassembled into its components for a newround of translation. Here, we show that a Saccharomyces cerevisiae model PoTC was disassembled by ATP and eukaryotic elongation factor 3 (eEF3). GTP or ITP functioned with less efficiency and adenosine 5γ′-(β,γ-imido)triphosphate did not function at all. The kcat of eEF3 was 1.12 min-1, which is comparable to that of the in vitro initiation step. The disassembly reaction was inhibited by aminoglycosides and cycloheximide. The subunits formed from the yeast model PoTC remained separated under …

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Synthesis, Characterization And Biological Activity Of Copper (Ii) And Zinc (Ii) Complexes Of Thiosemicarbazones And Their N(4)-Substituted Derivatives Derived From 2,4-Dihydroxybenzaldehyde., Tan Kong Wai Jan 2010

Synthesis, Characterization And Biological Activity Of Copper (Ii) And Zinc (Ii) Complexes Of Thiosemicarbazones And Their N(4)-Substituted Derivatives Derived From 2,4-Dihydroxybenzaldehyde., Tan Kong Wai

Student Works (2010-2019)

Four thiosemicarbazones ligands (1-4) have been prepared with good yield by refluxing 2,4-dihydroxybenzaldehyde with thiosemicarbazide or N(4)-substituted thiosemicarbazide in ethanol or methanol. From these four ligands, 16 new ternary metal complexes (5-20) with the general formulation of M(B)L have been prepared from the reactions of metal acetates with 2,4-dihydroxybenzaldehyde N(4)-substituted thiosemicarbazone in the presence of N,N-heterocyclic base (M2+ = Zn2+ or Cu2+; B = 2,2'-bipyridine, (bpy); 1,10-phenanthroline, (phen); L2- = doubly deprotonated thiosemicarbazones = 2,4-dihydroxybenzaldehyde thiosemicarbazonato, (HT); 2,4-dihydroxybenzaldehyde 4-methylthiosemicarbazonato, (HM); 2,4-dihydroxybenzaldehyde 4-ethylthiosemicarbazonato, (HE) and 2,4-dihydroxybenzaldehyde 4-phenylthiosemicarbazonato, (HP)) These compounds have been characterized by elemental analyses, IR, UV-Vis, NMR and magnetic …

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1-Alkyl-3-Methylimidazolium Bis(Trifluoromethylsulfonyl)Imide Based Ionic Liquids: A Study Of Their Physical And Electrochemical Properties, Charles William Dutton Jan 2010

1-Alkyl-3-Methylimidazolium Bis(Trifluoromethylsulfonyl)Imide Based Ionic Liquids: A Study Of Their Physical And Electrochemical Properties, Charles William Dutton

Browse all Theses and Dissertations

Ionic liquids are of interest because of their electrochemical and thermal properties and their possible use as electrolytes in batteries. In this work five ionic liquids were synthesized. They consisted of a 1-alkyl-3-methylimidazolium (RMI+) cation, where the alkyl group was ethyl, propyl, butyl, pentyl, or hexyl, and a bis(tri-fluoromethylsulfonyl)imide (NTf2-)anion. The decomposition temperatures, melting points, conductivities, viscosities, densities, absorption and desorption of water, diffusion coefficients, and electrochemical properties were studied. It was found that these ionic liquids were thermally stable up to ~310 °C, and that EMINTf2 had a melting point at -18.26 °C. Conductivities …

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Routes To Sydno[3,4-A]Quinoxalines, Erik Dihrkop Jan 2010

Routes To Sydno[3,4-A]Quinoxalines, Erik Dihrkop

Browse all Theses and Dissertations

In the present work, the reactivity of alkyl and aryl sydnoquinoxalines was studied. Using a previously developed method, triphenylphosphine-2-(3-sydnonyl)phenylimide was prepared in a two-step process via a diazotization / azidation process of 3-(2-aminophenyl)sydnone, followed by treatment with triphenylphosphine. Due to the inability to achieve previously reported yields, a new, one-step method using Mitsunobu conditions was employed to synthesize the iminophosphorane in a good yield. A similar, brominated iminophosphorane was synthesized using the same conditions in a good yield. Treatment of both the brominated and non-brominated iminophosphoranes with alkyl and aryl isocyanates or isothiocyanates in an aza-Wittig process, gave the corresponding …

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Skeletal Pathology Of Tibiotarsi In Chick Embryos Exposed To Platinum Group Metals By Micro-Raman Spectroscopy, Jennifer L. Monahan Jan 2010

Skeletal Pathology Of Tibiotarsi In Chick Embryos Exposed To Platinum Group Metals By Micro-Raman Spectroscopy, Jennifer L. Monahan

Browse all Theses and Dissertations

Platinum group metals (PGMs) have been shown to accumulate in various tissues of organisms but their toxicity is not well-known. Raman spectroscopy is a powerful analytical technique that enables direct and non-destructive chemical characterization of bone tissues. PGMs were injected into chick embryos in the following concentrations: 0.1, 1.0, 5.0, or 10.0 ppm solutions of Pt(IV), Rh(III), Pd(II) or PGMs mixtures (0.1 ppm or 1.0 ppm of each metal). The micro-Raman maps recorded on the paraffin embedded tibiotarsus cross-sections showed significant changes in the chemical composition and structure of the bone tissue as a result …

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Temperature And Ph Responsive Polyethylenimine Systems As Potential Nonviral Gene Vectors, S. Chad Skidmore Jan 2010

Temperature And Ph Responsive Polyethylenimine Systems As Potential Nonviral Gene Vectors, S. Chad Skidmore

Browse all Theses and Dissertations

Modified HPEI was used to determine if the LCST could be controlled by varying multiple variables, including: percent modification, pH, salt solution concentration, and weight percent. Two modifications were done with butylene oxide (Butox) and isobutyryl amide (IBAm). Specifically, 100% (HPEI-Butox1.00)butoxylated and 10% (HPEI-IBAm0.10), 54% (HPEI-IBAm0.54), and 70% (HPEI-IBAm0.70) amidated samples were synthesized. Additionally, HPEI-IBAm0.54 was further modified with hydroxyl ethyl groups (HPEI-IBAm0.54 Eox0.46) and ethyl groups (HPEI-IBAm0.54-Et0.44). The LCSTs of all amidated systems were below body temperature, 37 °C, at pH = 7.4. This indicates an ability of these systems to be used as a vector for gene delivery. …

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Small Molecule Caspase Inhibitors Using Isatin And Oxindole Scaffolds And A Combinatorial Approach, Hagar Mahmoud Abdallah Jan 2010

Small Molecule Caspase Inhibitors Using Isatin And Oxindole Scaffolds And A Combinatorial Approach, Hagar Mahmoud Abdallah

Browse all Theses and Dissertations

Quinolyl-valyl-O-methylaspartyl-[2,6-difluorophenoxy]-methyl ketone (Q-VD-OPh) is a next generation broad spectrum caspase inhibitor, the effectiveness and reduced toxicity of which can be partially attributable to the carboxyterminal O-phenoxy group as well as the amino terminal quinolyl groups. We seek to incorporate some of these unique recognition elements onto small molecule derived protease inhibitors with drug like properties. Specifically, heterocyclic scaffolds such as isatins and oxindoles. Thus, isatins bearing electron withdrawing groups on C-5 and 2,6-difluorobenzyl moieties have been prepared by analogy to the well studied N-substituted 5-pyrrololidinylsulfonyl isatins. Moreover, 3-benzylidene oxindole derivatives bearing these structural motifs have also been prepared and their …

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Progress Towards The Synthesis Of Type B Polycyclic Polyprenylated Acylphloroglucinol 7-Epi-Clusianone, Pushpa Suresh Jayasekara Mudiyanselage Jan 2010

Progress Towards The Synthesis Of Type B Polycyclic Polyprenylated Acylphloroglucinol 7-Epi-Clusianone, Pushpa Suresh Jayasekara Mudiyanselage

University of Kentucky Doctoral Dissertations

Plants of the family Guttiferae produce polycyclic polyprenylated acylphloroglucinols (PPAPs), which have interesting biological activities including anticancer and antibacterial properties. The main structural features of PPAPs comprise of bicyclo[3.3.1]nonane-2,4,9-triketone with one acyl group together with prenyl, geranyl, or other C10H17 groups. 7-epi-Clusianone, a type B PPAP with C-7 endo stereochemistry, is being approached by establishing the cis relationship with C(4) allyl group and C(2) methyl ester in the early stage of the synthesis. Then C(2) methyl ester is converted to alkyne aldehyde and syn reduction followed by intramolecular aldol reaction to give bicyclo[3.3.1]nonane structure with …

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Corrosion Of Civil War Era Sub Marine Explorer—Part 1, Donald L. Johnson, James D. Carr, Brent M. Wilson, Larry E. Murphy, James P. Delgado Jan 2010

Corrosion Of Civil War Era Sub Marine Explorer—Part 1, Donald L. Johnson, James D. Carr, Brent M. Wilson, Larry E. Murphy, James P. Delgado

Department of Chemistry: Faculty Publications

The Sub Marine Explorer is one of five submersibles (submarines) constructed prior to 1870 that have survived either in museums or as in situ archaeological sites around the world. Since 1869, the wreck of Explorer has emerged at low tide on the beach of Isla San Telmo, Archipiélago de las Perlas, Panama, located ~75 km southwest of Panama City in the Bay of Panama. In 2001, James Delgado visited the site. Locals described the wreck as a World War II-era Japanese midget submarine. Delgado consulted with Richard Wills, an expert on American Civil War submarines, and confirmed that the well-preserved …

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Polymeric Paracest Mri Contrast Agents As Potential Reporters For Gene Therapy, Yunkou Wu, Christiane E. Carney, Michael Denton, Elaine Hart, Piyu Zhao, Daniel N. Streblow, A. Dean Sherry, Mark Woods Jan 2010

Polymeric Paracest Mri Contrast Agents As Potential Reporters For Gene Therapy, Yunkou Wu, Christiane E. Carney, Michael Denton, Elaine Hart, Piyu Zhao, Daniel N. Streblow, A. Dean Sherry, Mark Woods

Chemistry Faculty Publications and Presentations

Gene therapy is a potentially powerful treatment approach that targets molecular remedies for disease. Among other challenges it remains difficult to monitor gene delivery and its downstream metabolic consequences. Approaches to MRI gene reporters have been reported but few have the potential for translation beyond isolated cell systems. Herein, we report a polycationic polymer MRI contrast agent that binds to DNA in a ratio of one monomer unit per phosphate group of DNA. Significantly, this binding event diminishes the MR contrast signal from the agent itself potentially providing a platform for imaging delivery and release of a gene into cells …

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Nir Dyes For Bioimaging Applications, Jorge O. Escobedo, Oleksandr Rusin, Soojin Lim, Robert M. Strongin Jan 2010

Nir Dyes For Bioimaging Applications, Jorge O. Escobedo, Oleksandr Rusin, Soojin Lim, Robert M. Strongin

Chemistry Faculty Publications and Presentations

Fluorescent dyes based on small organic molecules that function in the near infra red (NIR) region are of great current interest in chemical biology. They allow for imaging with minimal autofluorescence from biological samples, reduced light scattering and high tissue penetration. Herein, examples of ongoing NIR fluorophore design strategies as well as their properties and anticipated applications relevant to the bioimaging are presented.

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Synthesis And Applications Of Ring Opening Metathesis Polymerization Based Functional Block Copolymers, Sanchita Biswas Jan 2010

Synthesis And Applications Of Ring Opening Metathesis Polymerization Based Functional Block Copolymers, Sanchita Biswas

Electronic Theses and Dissertations

Ring opening metathesis polymerization (ROMP) is established as one of the efficient controlled living polymerization methods which have various applications in polymer science and technology fields. The research presented in this dissertation addresses several applications of multifunctional well-defined norbornene-based block copolymers synthesized by ROMP using ruthenium-based Grubbs catalysts. These novel block copolymers were applied to stabilize maghemite nanoparticles, creating the superparamagnetic polymeric nanocomposites. The Jaggregation properties of the porphyrin dyes were improved via self-assembly with a customized norbornene polymer. Novel multimodal copolymer probes were synthesized for two-photon fluorescence integrin-targeted bioimaging. In Chapter 1 a brief overview of ROMP along with …

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Selective Adsorption Of Dibenzothiophenes On Activated Carbons With Metal Species Deposited On Their Surfaces, Jakub Lison Jan 2010

Selective Adsorption Of Dibenzothiophenes On Activated Carbons With Metal Species Deposited On Their Surfaces, Jakub Lison

Dissertations and Theses

"The objective of this thesis is an investigation of influence of porosity, surface chemistry, material composition and effects of metals oncarbon adsorbents in desulfurization of liquid fuels. Materials are derived from poly (4-styrenesulfonic acid-co-maleic acid) salts (sodium or transition metals). They are investigated in a dynamic breakthrough process using model diesel fuel containing dibenzothiophene (DBT) and 4, 6-dimethyldibenzothiophene (DMDBT). The performance of adsorbents is evaluated in terms of the capacity and selectivity. Differences in performance are investigated considering the porosity, surface chemistry and the type of material used."

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Modular Synthesis Of Weinreb Amides Of 2-Fluoro-2,4-Dienoic Acids, Mohammad Chowdhury Jan 2010

Modular Synthesis Of Weinreb Amides Of 2-Fluoro-2,4-Dienoic Acids, Mohammad Chowdhury

Dissertations and Theses

No abstract provided.

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Degradation Of Organic Matter In Water In The Presence Of Catalyst And Uv Radiation, Bimali Bandaranayake Jan 2010

Degradation Of Organic Matter In Water In The Presence Of Catalyst And Uv Radiation, Bimali Bandaranayake

Masters Theses

Organic contaminants specially dyes, presents in water is a major environmental problem. Organic compounds can be degraded completely in the presence of photocatalysts and UV radiation. The kinetics of degradation of three dyes was studied using a variety of UV photocatalytic materials. The dyes (methylene blue, malachite green, chrysodoine R) were chosen based on their polarity differences. Catalysts consisting of pure TiO2, mixed oxides of TiO2 containing SiO2, and others containing SiO2 and iron oxide, SiO2/ ZrO2/ CeO2, and CeO2/SiO2 were studied. The TiO2/ SiO2 and SiO2/ZrO2/CeO2 catalysts exhibited the highest degradation rates for methylene blue. The more hydrophobic pure …

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Nanoporous High Surface Area Silicas With Chelating Groups For Heavy Metal Ion Adsorption From Aqueous Solution, Kothalawalage Nuwan Kothalawala Jan 2010

Nanoporous High Surface Area Silicas With Chelating Groups For Heavy Metal Ion Adsorption From Aqueous Solution, Kothalawalage Nuwan Kothalawala

Masters Theses

Nanoporous high surface area silicas are an ideal substrate for the design of materials with useful properties via chemical surface modification. The adsorption of heavy metals for contaminated water detoxification is one potential application. In this work we have used three different kinds of silica substrates with varying pore structures; commercially available narrow pore and wide pore silica gels, as well as surfactant templated mesoporous SBA-15 exhibiting a relatively narrow pore size distribution. These silicas have each been subjected to post-synthesis modification with an organosilane consisting of ethylenediamine triacetic acid functionalities for chelation/adsorption of metal ions from aqueous solution. The …

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Selective Fluorescence Detection Of Cysteine And N-Terminal Cysteine Peptide Residues, Soojin Lim, Jorge O. Escobedo, Mark Lowry, Xiangyang Xu, Robert M. Strongin Jan 2010

Selective Fluorescence Detection Of Cysteine And N-Terminal Cysteine Peptide Residues, Soojin Lim, Jorge O. Escobedo, Mark Lowry, Xiangyang Xu, Robert M. Strongin

Chemistry Faculty Publications and Presentations

A new fluorogenic fluorescein derivative containing an α,β-unsaturated aldehyde moiety produces a selective fluorescent signal enhancement in the presence of cysteine or peptides containing N-terminal cysteine residues. The mechanism is based on synergistic covalent and supramolecular interactions.

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The Population Of Sap And Tsap Isomers In Cyclen-Based Lanthanide(Iii) Chelates Is Substantially Affected By Solvent, Kyle J. Miller, Ali A. Saherwala, Benjamin C. Webber, Yunkou Wu, A. Dean Sherry, Mark Woods Jan 2010

The Population Of Sap And Tsap Isomers In Cyclen-Based Lanthanide(Iii) Chelates Is Substantially Affected By Solvent, Kyle J. Miller, Ali A. Saherwala, Benjamin C. Webber, Yunkou Wu, A. Dean Sherry, Mark Woods

Chemistry Faculty Publications and Presentations

The square antiprism/twisted square antiprism ratio in LnDOTA-tetraamide chelates is a critical parameter in governing water-exchange kinetics and ultimately the utility of a chelate as a PARACEST MRI contrast agent. In LnDOTA-tetraamide chelates with tertiary amides, this ratio and the rate of interconversion between these two structural isomers are found to be dramatically dependent upon the solvent and possibly other local environmental factors.

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Design, Synthesis And Characterization Of New Two-Photon Absorbing (2pa) Fluorescent Dyes And Bioconjugates, And Their Applications In Bioimaging, Carolina D. Andrade Jan 2010

Design, Synthesis And Characterization Of New Two-Photon Absorbing (2pa) Fluorescent Dyes And Bioconjugates, And Their Applications In Bioimaging, Carolina D. Andrade

Electronic Theses and Dissertations

The development of new multiphoton absorbing materials has attracted the attention of researchers for the last two decades. The advantages that multiphoton absorbing materials offer, versus their one-photon absorbing counterparts, rely on the nature of the nonlinearity of the absorption process, where two photons are absorbed simultaneously offering increased 3D resolution, deeper penetration, and less photobleaching and photodamage as a result of a more confined excitation. The applications of efficient two-photon absorbing materials have been extensively expanding into the fields of photodynamic therapy, microscopy, and optical data storage. One of the fields where an increased interest in multiphoton absorbing materials …

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Chemistry Of Rhenium(I) Tricarbonyl Complexes Of Biomedical Relevance, Theshini Perera Jan 2010

Chemistry Of Rhenium(I) Tricarbonyl Complexes Of Biomedical Relevance, Theshini Perera

LSU Doctoral Dissertations

fac-[ReI(CO)3L]n complexes serve as models for short-lived fac-[99mTcI(CO)3L] imaging tracers. Dangling groups on L, needed to achieve desirable biodistribution, complicate the NMR spectra, which are not readily understood. In fac-[ReI(CO)3L]+ with less complicated L, NH groups (exo-NH) projecting toward the L face sometimes showed an upfield shift attributable to steric shielding of the exo-NH group from the solvent by the chelate rings. To investigate whether exo-NH groups in six-membered rings exhibit the same effect and whether the …

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Part I: Syntheses, Characterizations, And Investigations Of Molecular Micelles And Imidazolium-Based Ionic Liquids For Protein Separations In Electrophoresis Part Ii: Investigating The Mentoring Canon Through Exploration Of Thirty Years Of Mentoring By An Exemplar, Monica R. Sylvain Jan 2010

Part I: Syntheses, Characterizations, And Investigations Of Molecular Micelles And Imidazolium-Based Ionic Liquids For Protein Separations In Electrophoresis Part Ii: Investigating The Mentoring Canon Through Exploration Of Thirty Years Of Mentoring By An Exemplar, Monica R. Sylvain

LSU Doctoral Dissertations

The research reported in this dissertation is presented in two parts. The first part is the Syntheses, Characterizations, and Investigations of Molecular Micelles and Imidazolium-Based Ionic Liquids for Protein Separations in Electrophoresis, and the second part is a case study entitled Investigating the Mentoring Canon through Exploration of Thirty Years of Mentoring by an Exemplar. Protein separations in the gel electrophoretic format are ubiquitous analyses used on a daily basis throughout biochemistry, analytical chemistry, and biotechnology. The goal of the research reported in the first part of this dissertation is to synthesize and characterize molecular micelles and ether-functionalized imidazolium-based ionic …

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Development Of A Laser-Induced Breakdown Spectrometer For Lead-Free Gunshot Residue Analysis, Ryan Alexander Gregg Jan 2010

Development Of A Laser-Induced Breakdown Spectrometer For Lead-Free Gunshot Residue Analysis, Ryan Alexander Gregg

Honors Theses

Research has demonstrated that Laser‐Induced Breakdown Spectroscopy (LIBS) can be used as an effective method of screening for the common elemental components in gunshot residue. Barium (Ba), lead (Pb), and antimony (Sb) make up the primer cap of most ammunition involved in forensic gunshot residue analysis. Recently, ammunition manufacturers have started producing and popularizing ammunition with zinc (Zn), titanium (Ti), and gadolinium (Gd) primer components that are non‐toxic to the environment. This paper discusses the development of the Ole Miss Department of Chemistry and Biochemistry's first LIBS instrument for forensic analysis of lead‐free using Gd as a tracer element for …

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Synthesis And Reactivity Of Alpha-Azido Acylals, Gretchen Bell Jan 2010

Synthesis And Reactivity Of Alpha-Azido Acylals, Gretchen Bell

Honors Theses

alpha-Azido -Azido acylals are a novel combination of azide (N3) and acylal [R-C(OOCR)2] functional groups. Since these compounds are new chemical entities, little is known in the chemical literature about their physical, chemical, and biological properties. This synthetic methodology investigation sought to (1) develop a one-pot, two reaction method for preparing alpha-azido acylals and (2) investigate the chemical reactivity of alpha-azido acylals with phosphine reagents. Progress has been made and will be discussed regarding both the synthesis and reactivity of alpha-azido acylals. This work developed methods and processes that will have significant impact in our broader objective of exploring the …

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Immobilization Of Motile Bacterial Cells Via Dip-Pen Nanolithography, Dorjderem Nyamjav, Sergey Rozhok, Richard C. Holz Jan 2010

Immobilization Of Motile Bacterial Cells Via Dip-Pen Nanolithography, Dorjderem Nyamjav, Sergey Rozhok, Richard C. Holz

Chemistry Faculty Research and Publications

A strategy to bind bacterial cells to surfaces in a directed fashion via dip-pen nanolithography (DPN) is presented. Cellular attachment to pre-designed DPN generated microarrays was found to be dependent on the shape and size of the surface feature. While this observation is likely due in part to a dense, well formed mercaptohexadecanoic acid (MHA) monolayer generated via DPN, it may also simply be due to the physical shape of the surface structure. Motile Pseudomonas aeruginosa bacterial cells were observed to bind to DPN generated mercaptohexadecanoic acid/poly-L-lysine (MHA/PLL) line patterns, 'blocks' made up of eight lines with 100 nm spacings, …

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The Stereochemistry Of Selected Supramolecular Complexes Of Cucurbiturils And The Effect Of Homogeneous Equilibria And Electron Transfer Of The Guest, Arumugam Thangavel Jan 2010

The Stereochemistry Of Selected Supramolecular Complexes Of Cucurbiturils And The Effect Of Homogeneous Equilibria And Electron Transfer Of The Guest, Arumugam Thangavel

Doctoral Dissertations

"From a practical perspective, host-guest complexes are vehicles for understanding and using supramolecular interactions for purposeful function in sensors, molecular machines and switches, while from a fundamental perspective they may lead to novel supramolecular protection schemes in basic organic reactions. This dissertation examines the interactions of cucurbiturils as barrel-shaped hosts, exhibiting a hydrophobic cavity, with substituted benzoylpyrydinium, phenypyrylium, and diazaanthraquinonediium cations as guests. In water, N-methyl-4-(p-substituted benzoyl)pyridinium cations exist in equilibrium with their hydrated forms (gem-diols), whose concentrations depend on the para substituent. In the presence of cucurbit7uril (CB[7]), the benzoyl group shows a preference for the CB[7] cavity, and …

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Effect Of Structure And Plasticizer On The Glass Transition Of Adsorbed Polymer, Boonta Hetayothin Jan 2010

Effect Of Structure And Plasticizer On The Glass Transition Of Adsorbed Polymer, Boonta Hetayothin

Doctoral Dissertations

"The effect of molecular mass on adsorbed poly(methyl methacrylate) (PMMA) on silica was determined using temperature-modulated differential scanning calorimetry (TMDSC). A two-component model, based on loosely-bound polymer (glass transition temperature, Tg, similar to that of bulk) and tightly-bound polymer (Tg higher than that of bulk) was used to interpret the thermograms. Similar amounts of tightly-bound polymer were found for 450 and 85 kDa PMMA (0.78 mg/m²), while the 32 kDa sample had a smaller amount (0.48mg/m²). A comparison of adsorbed PMMA, poly(vinyl acetate) (PVAc), and poly(methyl acrylate) (PMA) on silica was made using the same technique. The …

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Modeling Hydrophobic Effects At Different Lengthscales, Jihang Wang Jan 2010

Modeling Hydrophobic Effects At Different Lengthscales, Jihang Wang

Theses and Dissertations

Understanding hydrophobic effects at different length scales is relevant to many complex and poorly understood everyday phenomena in materials science and biology. In this thesis, a variety of theory/computational methods in statistical physics and statistical mechanics are used to address three separated, but interconnected problems: (1) How solvation free energy scales with a partical size that is charged? This problem has never been attempted to solve before despite its immense importance in colloidal and protein solutions (J. Wang, D. Bratko, K. Leung and A. Luzar, Hydrophobic hydration at different length-scales: manipulating the crossover by charges, to be submitted to J. …

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Molecular Mechanics Studies Of Enzyme Evolutionary Mechanisms, Manoj Singh Jan 2010

Molecular Mechanics Studies Of Enzyme Evolutionary Mechanisms, Manoj Singh

All Dissertations

In the current dissertation, closely related studies to quantify the mechanism underlying enzyme evolution have been discussed. The HIV-1 protease and beta-lactamase enzymes were used as model systems for these studies. These are well known enzymes that are associated with drug resistance and are associated with the pathogenic diseases, and therefore, developing molecular level understanding of drug resistance through these enzymes has fundamental as well as practical importance.
In chapter 2, the relationship between errors in modeled protein structures and associated binding affinity predictions to small molecules is established. The results of this study are applicable in addressing a wide …

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Molecular Dynamics Simulations Of Human Quadruplexes In K+ Solution And The Role Of The Carboxyl Terminus Of Bacteriorhodopsin In Protein Stability, Farah Rezae Jan 2010

Molecular Dynamics Simulations Of Human Quadruplexes In K+ Solution And The Role Of The Carboxyl Terminus Of Bacteriorhodopsin In Protein Stability, Farah Rezae

Seton Hall University Dissertations and Theses (ETDs)

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Synthesis Of Novel Glycosylidene-Based Quinolines, Peter H. Dobbelaar Jan 2010

Synthesis Of Novel Glycosylidene-Based Quinolines, Peter H. Dobbelaar

Seton Hall University Dissertations and Theses (ETDs)

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