Thesis (Ph. D.)--University of Virginia, 2000. / Includes bibliographical references (leaves 132-157). Also available online through Digital Dissertations.

During the last ten to fifteen years, a new class of electronic imaging devices has been created. Closely related to the visible-light Charge-Coupled Device, or CCD, this new class of components has extended electronic imaging capability into the near, middle, and long-wave infrared regions of the electromagnetic spectrum. Most notable among these new components are the IRCCD, a monolithic device, and the hybrid imaging device, which employs separately optimized detector and readout assemblies. Since the creation of the first infrared imaging device, there has been a continual effort to improve performance. One of the many problems faced by the designers of such devices is that of spatial response nonuniformity. This investigation considers the impact of spatial response nonuniformity on thermal imaging. The analysis presented assumes the use of a platinum silicide hybrid imaging device intended to operate in the 3-5 μm middle-wave IR band. Both linear and nonlinear models for its operation are developed. Using these models, estimates of system performance are made. Post-correction spatial noise is estimated for two popular nonuniformity correction schemes. To demonstrate the validity of these concepts, results obtained from actual device testing are presented. Upper bounds are established for the amount of nonuniformity present in the tested device. To complete the investigation, conventional detector figures of merit are then modified to include the effects of nonuniformity.

No description available.

No description available.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1959. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Brothers is a novel about Evan Floyd, a twenty-one year old college student who battles alcoholism, and his attempt to track down whoever injured his twin brother, Will. Evan meets Rolando Villanueva, a star on the local high school soccer team and the half-brother of Victor Villanueva, the man who hospitalized Will. The novel’s chapters alternate focal characters, as the novel’s first chapter employs a third-person, limited omniscient point of view with Evan as the focal character. The story remains in a third-person, limited omniscient point of view in the chapters where Rolando acts as the focal character. In addition to these two points of view, Edison Floyd, Evan and Will’s father, acts as a third focal character during a flashback sequence. The critical introduction for the novel examines how the focalization functions throughout the text.

Focal adhesion kinase (FAK) controls the assembly of focal adhesion sites and transduces signals from several membrane receptors. Controlled activation and localization of FAK functionally links cell adhesion, migration and survival. FAK is overexpressed in many cancer types, promoting tumor invasiveness and metastasis. The molecular mechanisms allowing FAK to fulfil numerous different functions and act as versatile ‘nanomachines’ are poorly understood. We have previously revealed that ligand-induced dimerization along with intramolecular interactions control FAK activation and localization where the C-terminal focal adhesion targeting (FAT) domain is strictly involved. In this study, we combine NMR with X-ray crystallography, as well as biophysical and computational methods to understand the molecular mechanisms that link the large-scale dynamics and intramolecular and intermolecular interactions of FAT into FAK’s capacity to integrate various stimuli into a site-specific function. Our results reveal FAT-mediated dynamical interplays between binding of known and newly discovered FAT ligands, and multimerization and autoactivation of FAK. Additionally, we investigate the impact of neuronal alternative splicing on FAT dynamics and interactions. Collectively, our results elucidate FAT’s role in allosterically controlling various FAK functions, and might inspire allosteric protein-protein interaction inhibitors against FAK-dependent cancer cell proliferation.

In this study, detailed characteristics and performance assessment of 3&amp / #8722 / 5 &micro / m p-i-n InSb photodetectors on Si substrates are reported. The detector epilayers were grown on GaAs coated Si substrates by molecular beam apitaxy (MBE). Both homojunction and single heterojunction (AlInSb/InSb) detector structures were investigated. Arrays of 33x33 &micro / m2 detectors were fabricated and flip-chip bonded to a test substrate for detailed electrical and optical characterization. A peak detectivity as high as 1x1010 cmHz1/2/W was achieved with InSb homojunction detectors on Si substrate in spite of the large lattice mismatch between InSb and Si (%19). In both homojunction and single heterojunction structures the differential resistance is significantly degraded by trap assisted tunneling (TAT) under moderately large reverse bias and by ohmic leakage near zero-bias. While the heterojunction structures provide a higher 80 K zero bias differential resistance, the responsivity of this structure is significantly lower than that of homojunction InSb photodiodes. In both homojunction and heterojunction photodetectors, 80K 1/f noise is dominated by TAT processes, and the noise current at 1 Hz follows the empirical relation in= &amp / #945 / TAT(ITAT) &amp / #946 / with &amp / #945 / TAT&amp / #8764 / 1.1x10&amp / #8211 / 6 and &amp / #946 / &amp / #8764 / 0.53.

Objetivos: Reportar la experiencia en cirugía resectiva en una serie de pacientes adultos con epilepsia focal lesional tratados en un hospital del Seguro Social del Perú. Material y Métodos: Se revisó la información registrada en la Unidad de Epilepsia de Adultos del Hospital Rebagliati, en Lima, desde enero del 2012 hasta octubre del 2016, sobre características clínicas, electrográficas, de neuroimagen y quirúrgicas de todos los pacientes con epilepsia focal lesional farmacorresistente, en los cuales se efectuó cirugía resectiva de epilepsia. La eficacia del procedimiento fue valorada mediante la Escala de Engel. Resultados: Se describen los resultados de cinco pacientes,proveyéndose información pertinente respecto a historia de la enfermedad, diagnósticos precisos, procedimientos quirúrgicos, seguimiento y complicaciones neurológicas y psiquiátricas. Conclusiones: La cirugía de epilepsia resectiva, basada en un trabajo multidisciplinario es reportada por primera vez en esta pequeña serie, demuestra ser eficaz y segura en adultos con epilepsia refractaria tratados en el Seguro Social del Perú. / Objectives:To report the experience of resective surgery in a series of adult patients with lesional focal epilepsy seen in a hospital of Peru’sSocial Security system. Material and Methods:Data of the Adult Epilepsy Unit at Rebagliati Hospital in Lima, from January 2012 to October 2016 were reviewed. Information was obtained about clinical, electrographic, neuroimaging and surgical procedures of all patients with refractory lesional focal epilepsy, in whom resective epilepsy surgery was performed. Efficacy was evaluated using the Engel scale. Results: Analytic data of five patients with pertinent details regarding clinical history, diagnostic work-up, surgical procedures, follow-up and neurological and psychiatric complications, are presented and discussed. Conclusions: Resective epilepsy surgery, based on a multidisciplinary work and reported in this small first sample appears to be effective and safe in adults with refractory epilepsy seen in a Social Security facility from Peru.

The properties of electrostatic quadrupole lenses are investigated both theoretically and experimentally. A method for measuring the effective lens length is developed and used. Previously reported (6) focusing equations for the two lens system provide an implicit solution involving trigonometric and hyperbolic functions. A nomograph was designed as an aid in carrying out this solution numerically. The two lens system was evaluated for various combinations of object distance, lens separation and image distance. Measured values of focal strengths were compared to theoretical values. Finally, measurements were made on the effective focal strength as a function of radial displacement from the central axis. / Thesis / Master of Science (MSc)