This project was launched with the key objectives of studying the characteristics of the aquifer at the Paddock bend floodplain and its reaction to possible recharges from falling rainfall and the nearby Trinity River. This aquifer is composed of different alluvial layers such as silt, clay and sand which are perched on top of a layer of relatively impermeable limestone. They are in hydraulic contact with the Trinity River and they have a variable vertical and aerial extent. An attempt made to estimate the hydraulic conductivity suggests that this alluvial aquifer has a very low (70.4m/year) hydraulic conductivity which is related to its clay-silt dominated subsurface composition. Groundwater is encountered at a depth of 9 to 25 ft below the ground surface with the highest elevation (525 ft above mean seal level) of the water table on the western part of the project site. The water level map and the data collected through the monitoring network in the area show that groundwater flows in a northeasterly direction toward the Trinity River. Detailed analysis of the water level hydrographs and hourly rainfall hyetographs for the period of this research show the seasonal fluctuation of the water level in the aquifer with water level falling in the summer and then rising in the fall. Furthermore, the strong correlation of the water level changes with the rainfall suggests that such water level changes are the result of groundwater recharge from the percolating rain. Such water level rises from individual storm events, how ever, are very small compared to the amount of rainfall and the aquifer response is slow and the water level changes are small due to due to the low degree of infiltration of rainwater from through the aquifer materials. Groundwater recharge from the Trinity River seems to have a very negligible effect on the water level in view of their hydraulic head differences as well as the hydraulic conductivity of the aquifer materials which are in contact with Trinity River. During the period of this research, the Trinity River Elevation remained almost stable through time while the groundwater elevations became very low during summer and early fall. Therefore, there could have been slight degree of groundwater recharge from the river during such dry seasons where the rate of evapotranspiration is very high and the amount of rainfall is very low.

A bi-directional relationship exists between the immune system and the central nervous system. A number of in vivo studies have reported that immune stimulation through administration of endotoxin or pro-inflammatory cytokines can lead to cognitive deficits in a variety of paradigms. However, despite a large body of work characterizing the behavioral effects of immune stimulation, the cellular mechanisms that underlie this global cognitive impairment remain unclear. The present study utilized primary hippocampal cell culture to examine the effect of pro-inflammatory cytokines on process extension and expression of relevant proteins. Specifically, we hypothesized that administration of interleukin-1beta (IL-1beta), interleukin-6 (IL-6), or tumor necrosis factor-alpha (TNF-alpha) would lead to morphological alterations (as evidenced by decreased process length, process number, and density of processes), and decreased protein and gene expression of GAP-43 and synapsin-I, two proteins important in synapse formation and process extension. Furthermore, in addition to replicating the prior findings of Neumann et al (2002) with regard to TNF-alpha, our goal was to extend this line of investigation to IL-1beta and IL-6. The observed results were generally inconsistent to our original hypotheses. Rather than decreasing expression, exposure to TNF-alpha led to significantly increased expression of synapsin-I mRNA, and exposure to IL-1beta, IL-6, and TNF-alpha led to significant increases in expression of synapsin-I protein. However, pro-inflammatory cytokine treatment did not significantly impact gene or protein expression of GAP-43. Further, these changes in synapsin-I, though correlated, did not significantly impact cellular morphology, in terms of process number, length, and density. The present study is the first to investigate the effects of IL-1beta or IL-6 on primary hippocampal neurons.

The work in this thesis focuses on the reactions of H-phosphinic acid derivatives, especially those developed in the Montchamp laboratory to construct new bonds from carbon to phosphorus. Chapter one consists of a review of the literature, with an emphasis on the reactivity of these substrates. Chapter two details recent advances in the laboratory for the hydrophosphinylation of H-phosphinic acids with alkenes. This reaction can be considered a `P-H' bond activation, as the palladium catalyst employed is shown to insert into the bond. Chapter three details the findings of a major reaction advancement made concerning the cross-coupling of H-phosphinic acid esters with aryl halides. A detailed investigation of the reaction is disclosed, including scope and preliminary mechanistic factors. A major discovery in the Montchamp laboratory, the use of ethylene glycol as a co-solvent, allowed for each reaction to take place.

Several metal containing molecules, including MgCN, NaCN, KCl, AlOH, and AlF have been observed in the interstellar medium. Additionally, transition metals have been observed. Many carbon containing molecules have also been observed in astrophysical sources. The purpose of the present research is to provide information on the spectral properties of metal carbide molecules that are potentially observable in space. Additional interest for studying small metal carbide molecules is the understanding of larger clusters including metallofullerenes and metallocarbohedrenes, and the catalytic growth of carbon nanotubes. FTIR spectra were obtained by condensing the vapor produced by dual laser ablation of metal and carbon rods in an argon matrix at ~12K. Comparison of the observed <super>13</super>C enriched vibrational spectra to the DFT simulated isotopic spectra has enabled the identification of vibrational fundamentals of linear MnC₃, linear MgC₃<super>-</super>, and chain ZnC₃. The linear MnC₃ has been detected for the first time. Its &nu;₁(&sigma;) vibrational fundamental has been observed at 1846.9 cm<super>-1</super>. Although previous photoelectron studies by Wang and Li have reported evidence for the cyclic isomer of MnC₃, their assignment was inconclusive since the linear and fanlike structures have been found to lie very close in energy, and the observed PE frequency matched the frequencies predicted for the vibrational fundamentals of both the linear and the fanlike isomers of MnC₃. Theoretical investigations of MgC₃<super>-</super> have indicated that the bent, linear, fan and kite structures are close in energy, and thus are potentially observables. In the present work, the &nu;₁(&sigma;) asymmetric carbon stretching mode of linear MgC₃<super>-</super> has been observed at 1797.5 cm<super>-1</super>. A second absorption at 1190.1 cm<super>-1</super> which is correlated in intensity to the &nu;₁(&sigma;) has tentatively been assigned to the &nu;₂(&sigma;) vibrational fundamental. Although DFT calculations on ZnC₃ have indicated that the linear, bent and kite structures are very close in energy, in the present research one vibrational fundamental of bent ZnC₃ in its <super>1</super>A&rsquo; state was observed at 1858.9 cm<super>-1</super>.

The focus of this research was the clarification of discrepancies found within the historic suspended sediment record for the Upper Brazos River, specifically at South Bend and Seymour, TX, as well as quantifying sediment transport dynamics within the upper basin. Flow duration curves constructed for the Brazos River indicate that both Seymour and South Bend experience similar high and low flow regimes, with the magnitude of the flow being the only difference. Contemporary samples at Seymour and South Bend produced specific sediment yields of 70 t km-2 yr-1 and 62 t km-2 yr-1 respectively. Heavy rainfall within the upper basin region of the Brazos River typically produces negative hysteresis within the sediment discharge. These concentrations are greater as discharge is dropping, this occurs in this reach of the Brazos because most of the sediment supplied to the river is from distant upstream reaches rather than immediately up river and proximal to the gaging station.

The Ordovician Viola Formation outcrops extensively in the Arbuckle Mts of Oklahoma. The Viola is well exposed on I-35, particularly on the southern limb of the Arbuckle anticline. Based on their petrographic characteristics, ten intervals have been recognized in this exposure.. In ascending order lithologies consist of poorly washed biosparites with variable peloids and intraclasts, a phosphatic-pyritic hardground, organic carbon rich shale, fossiliferous micrites and dismicrites, packed sparites, sandy sparites, and grainstones. Ternary petrographic plots of the Viola have been used to delineate compositional fields for the different intervals. Previous work has suggested that a shallowing upward trend controlled facies development during the entirety of the deposition of the Viola. This work demonstrates that, while an overall shallowing upward motif is present, detailed facies analysis indicates that several minor fluctuations in water depth took place during deposition of the Formation

Exposure to stress early in development can have lifelong effects on an organisms physiological and psychological health. Prior research suggests that prenatal stress exposure, among other effects, can lead to hyper-reactivity of the offsprings HPA axis and alterations in immune function. These stress-induced changes have been linked to a greater propensity to develop depression or an anxiety disorder in both human and non-human animals. Furthermore, prenatally stressed offspring have been found to be more susceptible to certain diseases, relative to non-stressed controls. The immune alterations induced by prenatal stress exposure may disrupt the normal communication between the immune system, endocrine system, and central nervous system, potentially making prenatally stressed individuals more vulnerable to the negative aspects of immune activation, namely cytokine-induced cognitive deficits and increased anxiety. The present study investigated whether prenatal stress exposure would exaggerate these detrimental effects of immune activation. Specifically, we hypothesized that prenatally stressed subjects would be hypersensitive to endotoxin administration and would therefore show exaggerated learning deficits, increased anxiety-like behavior, and increased peripheral and central interleukin-1b production. The observed results only partially supported our hypotheses, as prenatally stressed subjects showed evidence, albeit modest, of increased anxiety-like behavior following endotoxin administration relative to non-stressed controls. However, the data failed to support the primary hypothesis that prenatally stressed subjects would show exaggerated cognitive deficits, engendered via enhanced peripheral and central IL-1b production, following immune activation. Collectively, these data suggest that while prenatal stress exposure may lead to increases in anxiety-like behavior following a subthreshold dose of endotoxin, it does not appear to produce greater susceptibility to LPS-induced cognitive decline or elevations in proinflammatory cytokine production.

The integration of recent, multifactor theories of Parkinson's disease (PD) etiology into animal models of the disease comprise a relatively small portion of the research. In most environmental models of PD, a single neurodegenerative agent is introduced to cause nigrostriatal dopamine depletion. It has been argued, however, that cell loss in human PD often might derive, at least in part, from multiple toxins or vulnerabilities, any one of which alone does not lead to chronic dopamine depletion. Based on previous in vitro research, two agents were delivered to mice peripherally to promote chronic dopamine depletion and neurological impairment: the inflammatory bacterial endotoxin, lipopolysaccharide (LPS) and the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Male C57BL/6J mice received treatment with LPS+MPTP, MPTP-only, LPS-only, or saline and then were evaluated for four months on stride length and motor function in an open field. Mice in the two-factor (LPS+MPTP) group, but not in the single-factor groups, showed dopamine depletion and impaired motor function, including reduced stride length at four months post-injection. The LPS- and MPTP-only groups showed no dopamine depletion or parkinsonian, behavioral deficits. These data are consistent with the view that nigrostriatal dopamine neurons conceivably might succumb chronically to multiple toxic agents that independently may have only a transient adverse effect. In addition to providing preliminary behavioral and neurochemical data consistent with PD, the present LPS+MPTP C57BL/6J mouse model holds advantages for evaluation of early PD that include use of (theoretically) causally-oriented toxic agents, relative cost effectiveness, and simple, systemic administration methods.

Two studies tested competing hypotheses explaining an attitude change phenomenon. Previous studies have shown a relationship between memory errors and attitudes, where attitude change has been found to follow source monitoring errors of imagined events. It is believed that writing hypothetical scenarios of detailed, first person accounts of interactions with a target group member, causes source monitoring errors to occur where the imagined events become confused with actual events in memory. People often look to their memories for information when reporting their current attitudes, and errors in attitude-relevant memories are suspected to lead to altered attitude reports. A competing hypothesis may be that attitudes change online while imagining interactions with a target group member and that the observed memory errors are a byproduct of changed attitudes. Study 1 showed that attitudes did not significantly change immediately after writing hypothetical scenarios of imagined interactions, but did change three weeks following the manipulation when memory errors were found to have occurred. Study 2 showed that memory errors were not found following a different attitude change manipulation that resulted in a similar magnitude of change. Here, again, attitude change did follow source monitoring errors resulting from writing hypothetical accounts of imagined attitude-relevant actions. Together, these studies suggest that the memory error account is more accurate than a memory bias account in explaining the attitude change that follows imagining attitude-relevant actions.

Previous research has shown that the opioid system is engaged during surprising reward loss events. Frustration theory predicts that the opioid systems modulatory influence on such situations is attributable to three potential mechanisms: comparison of received and expected rewards, intensity of the frustrative emotional response induced by this comparison, or consolidation of the frustration memory. Four experiments provide no supportive evidence for the hypothesis that the opioid system participates in the consolidation of the frustration memory. These experiments involved situations varying in terms of the type of reward reduction (complete or partial), the type of reward (solid food pellets or sucrose solutions), and the type of behavior system (anticipatory or consummatory behavior). A fifth experiment suggests that opioids distort the comparison between expected and received rewards, narrowing the possible opioid mechanisms to modulation of incentive comparison and/or the intensity of primary frustration.