Physics Commons^™

Influence Of Platinum Nanoparticles On Ionic Transport And Hydrogen Reactivity Of Yttria-Stabilized Zirconia Thin Films, Firas Mahyob

Electronic Theses and Dissertations

Yttria-stabilized zirconia (YSZ) is a widely used ceramic material in solid oxide fuel cells, oxygen sensors, and sensing applications due to its high ionic conductivity, chemical inertness, and thermal stability. YSZ is promising active coating for use in miniaturized harsh environment wireless surface acoustic sensors to monitor gases such as H₂. Adding catalytic Pt nanoparticles can enhance gas reactivity and lead to associated film conductivity changes.

In this work, thin films with an (8% Y₂O₃ - 92% ZrO₂) composition were deposited onto piezoelectric langasite substrates using RF magnetron sputtering in Ar:O₂ - …

Inhibitors Of Alpha-Synuclein Aggregation, Jemil Ahmed

Electronic Theses and Dissertations

Alpha-Synuclein (αS) – a neuronal, disordered, presynaptic protein – aggregates into amyloid fibrils and accumulates in the substantia nigra pars compacta of Parkinson's Disease (PD) patients. The aggregation and accumulation of αS amyloid fibrils leads to death of dopaminergic neurons; a hallmark of PD. Although it’s not clear why αS aggregates, prior studies have found that intrastriatal injection of fibril alone is sufficient to cause PD pathology in mouse and non-human primates models. These observations implicate αS as a therapeutic target against PD.

Unfortunately, there are three caveats when attempting to target αS. First, αS is a neuronal protein expressed …

Structure And Thermodynamics Of Polyglutamine Peptides And Amyloid Fibrils Via Metadynamics And Molecular Dynamics Simulations, Riley Workman

Electronic Theses and Dissertations

Aggregation of polyglutamine (polyQ)-rich polypeptides in neurons is a marker for nine neurodegenerative diseases. The molecular process responsible for the formation of polyQ fibrils is not well understood and represents a growing area of study. To enable development of treatments that could interfere with aggregation of polyQ peptides, it is crucial to understand the molecular mechanisms by which polyQ peptides aggregate into fibrils. Many experimental techniques have been employed to probe polyQ aggregation, however, observations from these studies have not lead to a unified understanding of the properties of these systems, instead yielding competing, fragmented theories of polyQ aggregation. This …

Surface Reaction And Diffusion Kinetics In Semiconducting Metal Oxide Film Gas Sensors, Aravind Reghu

Electronic Theses and Dissertations

Chemiresistive metal oxide gas sensors based on materials such as SnO₂, ZnO, and TiO₂, have been investigated extensively by many researchers for a wide range of applications. The band bending model, based on the surface chemistry of highly reactive ionosorbed species (O₂^- or O^-) and the semiconducting material properties of SnO₂, TiO₂ and ZnO, adequately predicts the dependence of the change in sensor conductivity (Δσ) as a function of target gas pressure and temperature. However, the band bending model is not applicable to gas sensors based on reducible oxides …

Artificial Olfactory System For Multi-Component Analysis Of Gas Mixtures., Alexander Aleksandrovich Larin

Electronic Theses and Dissertations

Gas analysis is an important part of our world and gas sensing technology is becoming more essential for various aspects of our life. A novel approach for gas mixture analysis by using portable gas chromatography in combination with an array of highly integrated and selective metal oxide (MOX) sensors has been studied. We developed a system with small size (7 x 13 x 16 inches), low power consumption (~10 W) and absence of special carrier gases designed for portable field analysis (assuming apriori calibration). Low ppb and even sub-ppb level of detection for some VOCs was achieved during the analysis …

New Methods For Measuring Transient Interactions Between Proteins And Curved Membranes, Philip P. Cheney

Electronic Theses and Dissertations

Variations in the physical deformation of the plasma membrane play a significant role in the sorting and behavior of the proteins that occupy it. Determining the interplay between membrane curvature and protein behavior required the development and thorough characterization of a model plasma membrane with well defined and localized regions of curvature. This model system consists of a fluid lipid bilayer that is supported by a dye-loaded polystyrene nanoparticle patterned glass substrate. As the physical deformation of the supported lipid bilayer is essential to our understanding of the behavior of the protein occupying the bilayer, extensive characterization of the structure …