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Full-Text Articles in Physical Sciences and Mathematics

Homologous And Heterologous Crystallin Protein Interactions As The Molecular Basis Of Inherited Cataract, Priya Ranjan Banerjee Jan 2011

Homologous And Heterologous Crystallin Protein Interactions As The Molecular Basis Of Inherited Cataract, Priya Ranjan Banerjee

Legacy Theses & Dissertations (2009 - 2024)

Age-related cataract is the most common cause of blindness worldwide. Nearly fifty percent of Americans above the age of 75 are diagnosed with this disease (http://www.nei.nih.gov/eyedata/pbd_tables.asp), and surgical intervention is the sole method of treatment at present (http://www.nei.nih.gov/healthyvision/objective/cataracts.asp). In the developing world, even this treatment is not readily available. These are compelling reasons to search for better treatments to delay, prevent or arrest cataract formation. Recent evidence suggests that age-related cataracts also have a genetic component. Therefore, determining the mechanisms underlying genetic cataracts with a known association to a protein-mutation is one important strategy towards understanding the molecular basis for …


Investigation Of Titanium Nitride As Catalyst Support Material And Development Of Durable Electrocatalysts For Proton Exchange Membrane Fuel Cells, Bharat Avasarala Jan 2011

Investigation Of Titanium Nitride As Catalyst Support Material And Development Of Durable Electrocatalysts For Proton Exchange Membrane Fuel Cells, Bharat Avasarala

Legacy Theses & Dissertations (2009 - 2024)

The impending energy and climatic crisis makes it imperative for human society to seek non-fossil based alternative sources for our energy needs. Although many alternative energy technologies are currently being developed, fuel cell technology provides energy solutions, which satisfy a wide range of applications. But the current fuel cell technology is far from its target of large scale commercialization mainly because of its high cost and poor durability. Considerable work has been done in reducing the cost but its durability still needs significant improvement. Of the various materials in a PEM fuel cell, the degradation of electrocatalyst affects its durability …


Significance Of Hno3 Acid Photolysis On Surfaces In Tropospheric Chemistry, Honglian Gao Jan 2011

Significance Of Hno3 Acid Photolysis On Surfaces In Tropospheric Chemistry, Honglian Gao

Legacy Theses & Dissertations (2009 - 2024)

The reactive nitrogen trace gases (NOy) including nitrogen oxides (NOx) and their secondary products are known to cause ground-level ozone pollution, photochemical smog, acid deposition, and overall air quality degradation. NOx was believed to be permanently removed from the atmospheric by HNO3 formation and deposition. However, our laboratory experimental results show that HNO3 can be remobilized back to photochemically labile HONO and NOx (re-NOx-ification). We have verified and quantified HONO and NOx production from the photolysis of HNO3 on various surfaces, including Pyrex, leaves of plants, and other environmentally relevant …


New Photoluminescent Copper(I) Complexes : Impact Of Bridging Carboxylates On Solid-State Structures And Photophysical Properties, Oleksandr Hietsoi Jan 2011

New Photoluminescent Copper(I) Complexes : Impact Of Bridging Carboxylates On Solid-State Structures And Photophysical Properties, Oleksandr Hietsoi

Legacy Theses & Dissertations (2009 - 2024)

Polynuclear copper(I) carboxylates exhibiting rich luminescent properties and a remarkable structural diversity have been the main focus of this investigation. In spite of the well-developed methods of copper(I) carboxylates synthesis, only a handful of complexes have been crystallographically characterized prior to our work. Notably, they all demonstrate different structural arrangements in the solid state. This dissertation describes the work that has been carried out towards the synthesis of new copper(I) carboxylates, the study of their molecular and solid-state structures, and their solid-state photoluminescent (PL) properties. In this work, we have prepared a series of new copper(I) carboxylates of the general …


In-Cell And In Vitro Studies Of Disease Related Protein-Protein Interactions Using Nmr-Spectroscopy, Andres Yudiel Maldonado Jan 2011

In-Cell And In Vitro Studies Of Disease Related Protein-Protein Interactions Using Nmr-Spectroscopy, Andres Yudiel Maldonado

Legacy Theses & Dissertations (2009 - 2024)

The receptor for advanced glycation end products (RAGE) is a multiligand cell surface macromolecule that plays a central role in the etiology of diabetes, inflammation, and neurodegeneration. The cytoplasmic domain of RAGE, ctRAGE, is critical for RAGE-dependent signal transduction. As the most membrane proximal event, mDia1 binds to ctRAGE and is essential for RAGE ligand-stimulated phosphorylation of AKT and cell proliferation/migration. We show that ctRAGE contains an unusual alpha-turn that mediates the mDia1-ctRAGE interaction and is required for RAGE dependent signaling. The results establish a novel mechanism through which an extracellular signal initiated by RAGE ligands regulates RAGE signaling in …


Structural Interactions And Dynamics Of Disease Related Proteins By Using Nmr Spectroscopy, Shadakshara Swamy Puttamadappa Jan 2011

Structural Interactions And Dynamics Of Disease Related Proteins By Using Nmr Spectroscopy, Shadakshara Swamy Puttamadappa

Legacy Theses & Dissertations (2009 - 2024)

Nuclear Magnetic Resonance (NMR) is a powerful spectroscopic technique to study the structure, molecular interactions, and dynamics of proteins. Modern NMR instrumentation, advancements in experimental techniques and revolutionary developments in recombinant DNA technology have made NMR a versatile and very convenient tool for biomolecule characterization.


Arsenic Speciation Analysis Of Biological Fluids : A Study Of Liquid Chromatography Coupled To Analytical Atomic Spectrometric Instrumentation, Kanna Ito Jan 2010

Arsenic Speciation Analysis Of Biological Fluids : A Study Of Liquid Chromatography Coupled To Analytical Atomic Spectrometric Instrumentation, Kanna Ito

Legacy Theses & Dissertations (2009 - 2024)

Arsenic exists as many different chemical forms including inorganic, methylated and dietary species. The toxicity of these species varies: some are highly toxic and can cause adverse health effects in many parts of the body; others are considered relatively non-toxic. Monitoring arsenic exposure is usually accomplished by its direct measurement in biological fluids. Urine is the specimen of choice for assessing arsenic exposure, because of its short biological half-life in blood. There have been very few studies of arsenic species in blood, yet such research can provide valuable information on arsenic distribution and its metabolism in the body.


Design And Development Of Highly Active, Nanoengineered, Platinum Based Core-Shell Electrodes For Proton Exchange Membrane Fuel Cells, Seth Louis Knupp Jan 2010

Design And Development Of Highly Active, Nanoengineered, Platinum Based Core-Shell Electrodes For Proton Exchange Membrane Fuel Cells, Seth Louis Knupp

Legacy Theses & Dissertations (2009 - 2024)

Highly active nanoengineered core-shell electrocatalyst have a great potential to be used as fuel cell electrodes. They can alleviate problems related with commercial carbon supported platinum by simultaneously lowering cost while enhancing reaction kinetics and overall performance. More recently, use of nanoengineered core-shell electrode structures have showed their ability to enhance the stability and overall lifetime of the catalyst without sacrificing the electrode's performance. We studied the potential of using highly active core-shell nanoparticles supported on carbon nanomaterials as fuel cell electrodes.


Elucidating The Structure Of Protein Aggregates By Raman Spectroscopy, Ludmila A. Popova Jan 2010

Elucidating The Structure Of Protein Aggregates By Raman Spectroscopy, Ludmila A. Popova

Legacy Theses & Dissertations (2009 - 2024)

The structures and properties of amyloid fibrils are of considerable interest due to their associations with numerous neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease and transmissible spongiform encephalopaties (prion diseases). Understanding fibrillogenesis at a molecular level requires detailed structural characterization of amyloid fibrils. However amyloid fibrils are difficult objects to study due to their non-crystalline and insoluble nature. These properties make the application of classical tools of structural biology, such as X-Ray crystallography and solution Nuclear Magnetic Resonance spectroscopy, impractical for structural characterization of protein fibrils.


Synthetic Studies On Angucycline C104, Rui Zheng Jan 2010

Synthetic Studies On Angucycline C104, Rui Zheng

Legacy Theses & Dissertations (2009 - 2024)

The Hauser's annulation and Hauser and Xu's route for C-aryl glycoside synthesis were successfully employed to prepare the linear tetracyclic anthraquinone substituted C-aryl glycoside, galtamycin as well as bis C-aryl glycosides. Synthetic studies on angucycline C104 extended the utility of both methods to structures with angular tetracyclic framework.


Heterometallic Beta-Diketonates And Oxo-Diketonates As Single Source Precursors For The Synthesis Of Oxide Materials, Haitao Zhang Jan 2010

Heterometallic Beta-Diketonates And Oxo-Diketonates As Single Source Precursors For The Synthesis Of Oxide Materials, Haitao Zhang

Legacy Theses & Dissertations (2009 - 2024)

The focus of this investigation was to develop a simple, high-yield synthetic approach to heterometallic diketonates using the same construction principles as for their polynuclear homometallic analogs. Several low-temperature solid-state synthetic routes were suggested that appear to be general for the preparation of heterometallic diketonates incorporating a wide range of s-, p-, d-, and f-metals. Using this investigative approach, two families of bimetallic homoleptic diketonates that contain heavy main group (BiIII, PbII) and the first row divalent transition metals (Mn, Fe, Co, Ni, Cu, and Zn) have been obtained. The heterometallic molecules that are held together by strong Lewis acid-base …


Genetically Engineered Repetitive Polypeptides : Design, Synthesis, Characterization, And Applications, Natalya I. Topilina Jan 2009

Genetically Engineered Repetitive Polypeptides : Design, Synthesis, Characterization, And Applications, Natalya I. Topilina

Legacy Theses & Dissertations (2009 - 2024)

This work is dedicated to the investigation of protein folding with the emphasis on the aggregation and amyloid fibrils formation. The focus of the research is to elucidate the relationship between polypeptide chain sequence and folding/aggregation properties. For this purpose, i) libraries of the de novo macromolecular repetitive β-sheet forming polypeptides were designed, and ii) the strategy for their rapid creation was developed. The strategy enables retention of a basic polypeptide core, yet allowing variations in the repetitive sequence, degree of polymerization and distribution of specific amino acids. The polypeptides were expressed in E. coli, purified, and characterized by various …


Raman Spectroscopy Of Body Fluids : A Nondestructive Identification Technique For Forensic Applications, Kelly Virkler Jan 2009

Raman Spectroscopy Of Body Fluids : A Nondestructive Identification Technique For Forensic Applications, Kelly Virkler

Legacy Theses & Dissertations (2009 - 2024)

The analysis of body fluid evidence during forensic investigations is a complicated process, yet it is a critical step in determining the key facts of a crime. There is no doubt that DNA analysis is an extremely useful tool that can identify a suspect or victim, but crime scene investigators must first locate and identify potential body fluid stains that can be collected for DNA analysis. Current screening tests are destructive to the sample and can give false positive results, so a nondestructive technique such as Raman spectroscopy, that can possibly confirm the presence of a particular fluid, could lend …


Bowl-Shaped Polyaromatic Hydrocarbons (Buckybowls) : Crystal Packing And Metal Binding Reactions, Alexander S. Filatov Jan 2009

Bowl-Shaped Polyaromatic Hydrocarbons (Buckybowls) : Crystal Packing And Metal Binding Reactions, Alexander S. Filatov

Legacy Theses & Dissertations (2009 - 2024)

This work is a part of a broad program in our laboratory dedicated to the investigation of a new class of non-planar polyaromatic hydrocarbons that map onto the surfaces of fullerenes (and referred to as buckybowls). It focuses on the preparation of buckybowls, their molecular and solid state structures, and reactivity in metal binding reactions. For the first time, the structures of all available buckybowls have been analyzed using X-ray diffraction data collected in the course of this work, as well as data previously obtained in our group or reported by others (and dearchived from the Cambridge Structural Database). Forces …


Measurement Of Atmospheric Ammonia Species : Development, Validation, And Field Applications Of An Analytical Method, Jian Hou Jan 2009

Measurement Of Atmospheric Ammonia Species : Development, Validation, And Field Applications Of An Analytical Method, Jian Hou

Legacy Theses & Dissertations (2009 - 2024)

Ammonia is the primary base in the atmosphere. It reacts readily with atmospheric acids such as sulfuric acid, nitric acid, and hydrochloric acid to form ammonium salts that occur predominantly in the fine aerosol particle (PM2.5) fraction. The ability to measure ammonia species (NHx, the sum of gaseous NH3 and particulate NH4+) is essential for the investigation of atmospheric behaviors of NHx. In this dissertation work, a highly sensitive technique has been developed for the measurement of atmospheric NHx species. The method is based on aqueous scrubbing of the atmospheric NH3 and NH4+ using …


Physical Properties Of Cytochromes C : 1. Role Of Cytochrome C' As A Nitric Oxide Carrier, 2. Folding Of Cytochrome C, Byunghoon Lee Jan 2009

Physical Properties Of Cytochromes C : 1. Role Of Cytochrome C' As A Nitric Oxide Carrier, 2. Folding Of Cytochrome C, Byunghoon Lee

Legacy Theses & Dissertations (2009 - 2024)

Cytochrome c’ binds and transfers endogenous NO in the denitrifying variant of Rhodobacter sphaeroides 2.4.3 and the NO bound ferrous heme that forms 5-coordinate resembles regulatory site in soluble guanylate cyclase. The Arg127 is close to the 5-coordiate NO bound heme of the cytochrome c’. The mutant (R127A) that was overexpressed in a cytochrome c’ knock-out R. sphaeroides 2.4.3 provided the opportunity to research the functional role of Arg127 in the redox potential and NO binding. The mutant (R127A) showed lower redox potential and lower NO binding free energy than wild type. ERP and ENDOR showed that the mutant had …


Biomonitoring For Exposure To Trace Elements In Utero : Analysis Of The Human Placenta, Pamela Catherine Kruger Jan 2009

Biomonitoring For Exposure To Trace Elements In Utero : Analysis Of The Human Placenta, Pamela Catherine Kruger

Legacy Theses & Dissertations (2009 - 2024)

The placenta forms in eutherian mammals, and is responsible for the nutrition of the developing fetus. However, maternal exposure to environmental pollutants both before and during pregnancy may result in the passage of toxins through the placental barrier and into fetal tissues. The placenta is the only organ derived from both maternal and fetal tissues, and establishes a link between the fetus and the environmental exposures of the mother. The analysis of placentae for the presence of environmental pollutants offers the possibility of exposure measurements in both the mother and the developing fetus. Specifically, trace element determination in human placentae …


Nanocomposite Thin Films Of Au Nanoparticles Embedded In Yttria-Stabilized Zirconia For Plasmonic-Based Harsh Environment Gas Detection, Phillip Henry Rogers Jan 2009

Nanocomposite Thin Films Of Au Nanoparticles Embedded In Yttria-Stabilized Zirconia For Plasmonic-Based Harsh Environment Gas Detection, Phillip Henry Rogers

Legacy Theses & Dissertations (2009 - 2024)

Increased health concerns due to the emission of gases linked to the production of tropospheric ozone by petroleum based fuel burning engines has resulted in the codification of more stringent emissions regulations domestically. Emissions regulations on commercial jetliners are one of the areas to be met with stricter standards. Currently there is not a sensing technology that can detect the emissions gases in the exhaust stream of a jet turbine engine with lower detection limits that meet these standards.