Physical Sciences and Mathematics Commons^™

Cloning, Overexpression, Purification And Characterization On N-Terminal Metal Binding Domains 5 And 6 Of Wilsons Disease Protein, David Achila

Masters Theses

Wilsons disease is an autosomal recessive disorder of copper metabolism which results from mutations in the gene encoding for Wilson disease protein (WDP). The cytosolic N-terminus of WDP comprises six metal binding domains each containing a conserved metal binding motif, GMXCXXC. The contribution of these metal binding domains to copper homeostasis is poorly understood. We have cloned, expressed and purified residues 485 to 633 corresponding to N-terminal metal-binding domains 5 and 6 of WDP (WD5-6). Two of the 3 disease causing mutations in the N-terminal metal binding domains of WDP occur one in each of these domains and the two …

A Study Of How Precursor Key Concepts For Organic Chemistry Success Are Understood By General Chemistry Students, Patrick Gerard Meyer

Dissertations

This study examines college student understanding of key concepts that will support future organic chemistry success as determined by university instructors. During four one-hour individual interviews the sixteen subjects attempted to solve general chemistry problems. A think-aloud protocol was used along with a whiteboard where the students could draw and illustrate their ideas. The protocols for the interviews were adapted from the Covalent Structure and Bonding two-tiered multiple choice diagnostic instrument (Peterson, Treagust, & Garnett, 1989) and augmented by the Geometry and Polarity of Moleculessingle-tiered multiple choice instrument (Furió & Calatayud, 1996). The interviews were videotaped, transcribed, and coded …

Systems For Predicting Pitzer’S Ion-Interaction Model Parameters, Theresa Balderas Obias

Masters Theses

Pitzer's Ion-interaction Model had been widely used in predicting the non-ideal behavior of solution over a wide range of conditions for natural water systems. The model is successful only when there are sufficient parameters available. However, generating these needed parameters requires a great quantity of work and it would be advantageous to be able to predict the Pitzer's parameters for salt systems when there is no data available.

This research entailed the development of ionic radii dependent equations for Pitzer's binary ion-interaction parameters β_MX⁽⁰⁾, β_MX⁽¹⁾, β_MX⁽²⁾, and C^ϕ_MX . …

Design, Synthesis And Characterization Of Nanosensors For Nerve Gas Agents, Thushara Gunasinghe

Masters Theses

This research is focused on the design synthesis and characterization of nanosensors to detect the nerve gas agents such as sarin at very low concentration levels (parts per billion and lower) which is very important to combat terrorism. Nanosensors constructed by the bottom up approach could provide the low sensitivity levels and high selectivity required for nerve gas detection. The sensing mechanism exploits the inherent properties of nanomaterials and signal amplification by signal transduction. The components of a nanoparticle-fluorescent monomer-nanomolecule-receptor (NMNR) sensor have been designed, synthesized, and characterized successfully. Interaction of the components of NMNR sensor with a model nerve …

Structure-Activity Relationship Studies On Thioxolone Compounds As Inhibitors Of Human Carbonic Anhydrase Ii, Jared Nyabuto Orwenyo

Masters Theses

Carbonic anhydrase II (CA II) is a zinc metalloenzyme that catalyzes the reversible hydration of carbon dioxide. The role of this reaction in physiology has made it a target of many therapeutic approaches. Most CA II inhibitors currently known are sulfonamide-based and this is the only functional group incorporated into rationally designed CA II inhibitors. Thioxolone (6-hydroxy-1, 3-benzoxathiol-2-one), is a non-sulfonamide that has been found to have CA II inhibitory activity.

Thioxolone and its analogs were studied to evaluate the inhibition activity that can be achieved upon modification of the thioxolone molecule. IC₅₀ values and dissociation constants were determined …

Ionic Liquid As Catalysts In The Cycloaddition Of Co2 To Styrene Oxide In Supercritical And Subcritical States, Joy Mwalimu

Masters Theses

Supercritical fluids (SCFs) have fascinated researchers ever since the discovery of a critical temperature more than a century ago.¹ Initial studies focused mainly on the physical properties of supercritical phases.² However, their use as reaction media has sparked mainly during the last five to ten years.²

The coupling of CO₂ and Ionic Liquids (ILs) in the synthesis of cyclic carbonates comes from an increasing need for environmentally and toxicologically benign processes for the production of high-value compounds. In my research, CO₂ was utilized as both a replacement solvent and a C₁ feedstock in its …

Acylpyrazolones: Synthesis, Self-Assembly And Lanthanide Metal Ion Separation, Jun Yang

Dissertations

The central hypothesis that nanoscale self-assemblies can provide excellent metal ion recognition has been substantiated by employing acylpyrazolones and trivalent lanthanide metal ions as model systems. Several novel acylpyrazolones and their amphiphilic analogs have been designed, synthesized, and characterized. Their lanthanide metal ion recognition efficacies have been demonstrated through baseline separations of a mixture of light, middle, and heavy lanthanide metal ions by employing them in the aqueous mobile phase of high performance liquid chromatography (HPLC) with octadecylsilanized silica (ODS) as the stationary phase. The complex separation mechanism is influenced by the structures of acylpyrazolone and amphiphilic moieties, and spontaneous …

Synthesis And Spectroscopic Characterization Of Manganese Doped Zinc Sulfide Quantum Dot Nanocrystals, Pedro A. Gonzalez Beerman

Dissertations

Zinc sulphide quantum dots were synthesized in aqueous media using sodium polyphosphate as the stabilizer. The nanoparticles were 2.5 ± 0.5 nm and 5.0 ± 0.5 nm diameter depending on the synthetic procedure employed and the amount of Mn doped varied from 0.003 to 0.32% (w/w). The nanoparticles were characterized by UV-Vis absorption, luminescence, EPR, near edge x-ray absorption fine structure (NEXAFS), and x-ray photoelectron spectroscopy (XPS), and x-ray diffraction (XRD), and transmission electron microscopy (TEM). These quantum dots show a strong emission at 590 nm due to the ⁴T₁ -⁶A₁ transition characteristic of Mn …

Rhizopine Synthesis – Potential Mediators For Nitrogen Fixation In Legume Plants, Venkat Reddy Guduru

Masters Theses

This research project focused on novel and efficient synthetic approaches of inosamine derivatives (rhizopines). The preparation of specific rhizopines would help elucidate the microbial pathway of rhizopine catabolism and degradation, and determine the role of corresponding genes during nitrogen fixation. We have investigated regio - and stereoselective transformations of myo-inositol derivative 28 utilizing an organostannane as key intermediate towards rhizopine 1a. The synthesis involved several protection and deprotection strategies to control competing reactivities of six hydroxyl groups of myo-inositol. Rhizopine 1a was prepared efficiently as a single isomer in 8 steps and 13% yield by controlling reactions …

Synthetic And Structural Studies Of Novel 1, 10-Phenanthroline Derivatives, Eunjoo Kim

Masters Theses

Asymmetric catalysis can provide a general approach to the preparation of enantiomerically enriched compounds in organic synthesis. Very often these asymmetric catalysts consist of a chiral ligand-metal complex. Because of the growing demand to develop enantioselective reactions in organic chemistry one focus of this area of research is the design and characterization of new chiral ligands for asymmetric synthesis.

The focus of my research is in the design, synthesis, and characterization of novel 1, 10-phenanthroline derivatives that could be used as chiral ligands in enantioselective reactions. Central to these studies have been the effect of substituents on the B-ring of …

Effect Of Antioxidants On Cadmium Induced Oxidative Stress And Signal Transduction, Deepti Goel

Masters Theses

A study was done to establish if reactive oxygen species (ROS) participate in the signal transduction pathway through which cadmium induces gene transcription. Cadmium has become a concern in the health care community in the past few years as evidence suggests that cadmium can induce the development of tumors, influence cell signaling and cause damage to organs, tissue, cells and DNA. The mechanism by which cadmium exerts its action on cellular processes or induces toxicity is however unclear although there is evidence to suggest that ROS play a role. Our laboratory is interested in understanding the mechanisms of differentially regulated …

Copper Exchange Studies Between The First And Fourth N-Terminal Metal-Binding Domains Of Wilson Disease Atpase, Jennifer Bunce

Masters Theses

The human copper-transporting ATPase Wilson's disease protein was one of the first proteins shown to be actively involved in cellular copper homeostasis. The protein includes six N-terminal metal binding domains. The individual capabilities of the domains to bind and transfer copper are not yet fully understood. Each metal-binding domain is about 72 amino acid residues long and contains the conserved binding motif GMTCXXC, of which the cysteines are involved in the copper coordination. Studies have shown that the protein binds six copper atoms suggesting the potential involvement of each metal-binding domain. Separate functional roles for the latter domains have been …