Counting Casualties in Communities Hit Hardest by the Foreclosure Crisis

The Foreclosure Crisis wreaked havoc on the finances of American households in a manner and to a degree not seen in almost a century. While most areas of the country are well on the road to recovery, the Crisis caused fundamental damage to the housing markets of some communities resulting in home-value declines that bear little hope of a meaningful recovery in the near future. Homeowners in these Hardest Hit Communities have suffered a serious economic loss on what is likely their principal asset, due in most cases to circumstances completely beyond their own control. The best long-term approach to remedying this situation may very well reside in a comprehensive package of carefully crafted policies aimed specifically at fixing housing markets in the Hardest Hit Communities—for example, geographically targeted home purchase tax credits along with public sector investments in housing rehabilitation, strategic demolition, and neighborhood stabilization programs. The federal government spends billions of dollars annually in tax incentives to bolster the American housing market, many of which are principally of value to high-income taxpayers who have relatively little need for them. The redirection of these dollars to those in the Hardest Hit Communities in order to restore confidence in their housing markets would be a more effective and equitable approach to accomplish the government’s stated objective of promoting home ownership. But the likelihood of generating the political will to marshal a comprehensive solution and oversee its implementation in a way that meaningfully impacts home values within the ownership tenure of most of those who bought homes in the Hardest Hit Communities prior to or in the midst of the Foreclosure Crisis is increasingly unlikely as time passes

Master of Science

thesisThe overall objective of this thesis was to examine skeletal muscle function and the development of peripheral quadriceps fatigue in health and in patients with chronic obstructive pulmonary disease (COPD). The aim of the first study was to further elucidate the role of afferent feedback in the regulation of locomotor muscle fatigue during dynamic exercise by varying the amount of active muscle mass. Utilizing cycling (BIKE) and single-leg knee extensor (KE) exercise, far greater quadriceps fatigue at exhaustion was observed following KE exercise. These data imply that when the source of skeletal muscle afferent feedback is confined to a small muscle mass, the central nervous system tolerates a greater magnitude of peripheral fatigue, and likely a greater intramuscular metabolic disturbance; a finding that has important implications for the adoption of small muscle mass exercise in rehabilitative medicine. The second study sought to determine the impact of an acute oral antioxidant cocktail (AOC), with previously documented efficacy, on free radical concentration and KE exercise performance in patients with COPD. In this population, recognized to have elevated oxidative stress, administration of the AOC significantly attenuated resting free radical levels, which were negatively correlated with the degree of airflow limitation and baseline MVC force. Upon secondary analysis, however, a dichotomous response to the AOC was recognized, whereby the AOC appeared to be most efficacious in those patients with high initial free radical levels, with minimal effects when the initial free radical load was low. Despite these antioxidant effects, no differences in KE exercise performance or the magnitude of peripheral quadriceps fatigue were evident following consumption of the AOC. These findings revealed that acutely reducing free radicals with an oral AOC does not translate to improved exercise capacity and fatigue resistance in patients with COPD. Collectively, this research has provided novel insight into the role of active muscle mass and the regulation of peripheral fatigue, and has better elucidated the link between free radicals, antioxidants, and fatigue in patients with COPD

Doctor of Philosophy

dissertationThe overall objective of this dissertation was to examine the impact of oxidative stress on oxygen transport and utilization, and ultimately physiological function, in older individuals and patients with chronic obstructive pulmonary disease (COPD). The goal of the first study was to better understand the age-associated attenuation in leg blood flow (LBF), with a focus on the role of redox balance, at rest and during exercise. Under control conditions, by experimental design, aging was associated with ~15% reduction in LBF. During knee extensor exercise (KE), the old also exhibited greater leg free radical outflow, assessed by electron paramagnetic resonance (EPR) spectroscopy, than the young. At rest, administration of an acute, oral antioxidant cocktail (AOC) increased antioxidant capacity, decreased the EPR signal, and consequently, restored LBF in the old such that it was not different from the young. During exercise, however, the AOC did not alter free radical outflow from the muscle or LBF. Thus, these data document exaggerated free radical production during exercise in older individuals exhibiting attenuated LBF, and identify a favorable effect of decreasing oxidative stress on resting hemodynamics in these individuals. However, the inability of the oral AOC to alter free radical outflow or LBF during exercise suggests that the formidable, pro-oxidant state elicited by exercise in the old likely necessitates a more potent antioxidant strategy to alter free radical outflow and potentially improve LBF in this population. The second study sought to determine the impact of acute, oral AOC administration on oxygen transport and utilization in a population recognized to have elevated oxidative stress, patients with chronic obstructive pulmonary disease (COPD). AOC administration led to an improvement in LBF during submaximal KE exercise, which was accompanied by an increase in muscle oxygen consumption, in the patients with COPD, but minimal effects in healthy subjects. Additionally, arterial oxygen saturation was improved in the patients with COPD, but unaltered in the healthy subjects. These results reveal detrimental consequences of elevated oxidative stress in patients with COPD in terms of vascular control, and oxygen transport and utilization during exercise. The third study examined the functional consequences of reducing oxidative stress in patients with COPD in terms of skeletal muscle fatigue development. Following intravenous ascorbate administration, an overall attenuation in the ventilatory and metabolic responses to high-intensity KE performed for the same duration and at the same intensity as the placebo condition was observed. Additionally, following the exercise matched for time, the patients exhibited less peripheral quadriceps fatigue. These results suggest a beneficial role for antioxidant administration in COPD, and further implicate oxidative stress in the systemic, pathophysiological consequences of the condition. Collectively, this research has identified novel, biological mechanisms by which oxidative stress may adversely impact oxygen transport and utilization in health and disease

Photo sensor array technology development

The development of an improved capability photo sensor array imager for use in a Viking '75 type facsimile camera is presented. This imager consists of silicon photodiodes and lead sulfide detectors to cover a spectral range from 0.4 to 2.7 microns. An optical design specifying filter configurations and convergence angles is described. Three electronics design approaches: AC-chopped light, DC-dual detector, and DC-single detector, are investigated. Experimental and calculated results are compared whenever possible using breadboard testing and tolerance analysis techniques. Results show that any design used must be forgiving of the relative instability of lead sulfide detectors. A final design using lead sulfide detectors and associated electronics is implemented by fabrication of a hybrid prototype device. Test results of this device show a good agreement with calculated values

In situ planetary mineralogy using simultaneous time resolved fluorescence and Raman spectroscopy

Micro-Raman spectroscopy is one of the primary methods of mineralogical analysis in the laboratory, and more recently in the field. Because of its versatility and ability to interrogate rocks in their natural form (Figure 1), it is one of the frontrunners for the next generation of in situ instruments designed to explore adiverse set of solar system bodies (e.g. Mars, Venus, the Moon, and other primitive bodies such as asteroids and the Martian moons Phobos and Deimos), as well as for pre-selection of rock and soil samples for cache and return missions

Arsenite-Induced Alterations of DNA Photodamage Repair and Apoptosis After Solar-Simulation UVR in Mouse Keratinocytes in Vitro

Our laboratory has shown that arsenite markedly increased the cancer rate caused by solar-simulation ultraviolet radiation (UVR) in the hairless mouse skin model. In the present study, we investigated how arsenite affected DNA photodamage repair and apoptosis after solar-simulation UVR in the mouse keratinocyte cell line 291.03C. The keratinocytes were treated with different concentrations of sodium arsenite (0.0, 2.5, 5.0 μM) for 24 hr and then were immediately irradiated with a single dose of 0.30 kJ/m(2) UVR. At 24 hr after UVR, DNA photoproducts [cyclobutane pyrimidine dimers (CPDs) and 6–4 photoproducts (6-4PPs)] and apoptosis were measured using the enzyme-linked immunosorbent assay and the two-color TUNEL (terminal deoxynucleotide transferase dUTP nick end labeling) assay, respectively. The results showed that arsenite reduced the repair rate of 6-4PPs by about a factor of 2 at 5.0 μM and had no effect at 2.5 μM. UVR-induced apoptosis at 24 hr was decreased by 22.64% at 2.5 μM arsenite and by 61.90% at 5.0 μM arsenite. Arsenite decreased the UVR-induced caspase-3/7 activity in parallel with the inhibition of apoptosis. Colony survival assays of the 291.03C cells demonstrate a median lethal concentration (LC(50)) of arsenite of 0.9 μM and a median lethal dose (LD(50)) of UVR of 0.05 kJ/m(2). If the present results are applicable in vivo, inhibition of UVR-induced apoptosis may contribute to arsenite’s enhancement of UVR-induced skin carcinogenesis

The Influence of Oxygen Fugacity and Cooling Rate on the Crystallization of Ca-Al Inclusions from Allende

Although there appears to be general agreement that some coarse-grained Ca-Al-rich inclusions (CAIs) from Allende passed through a molten or partially molten stage in their evolution, there are several competing hypotheses to account for the formation of the liquid phase in CAIs (e.g., 1-4). Studies of the phase equilibria of CAI compositions can help distinguish between these mechanisms for generating liquids in CAIs