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The neurostructural effects of prenatal exposure to methamphetamine in an infant population in the Western CapeWarton, Fleur Louise January 2017 (has links)
Prenatal methamphetamine exposure is associated with functional and neurostructural alterations, but neuroimaging investigations of these effects in infants are almost non-existent. Studies in neonates permit a degree of separation of drug exposure effects from potential confounders in the postnatal environment. Magnetic resonance imaging (MRI) was used to investigate the neurostructural effects of prenatal methamphetamine exposure on neonates recruited from a Cape Town community. Mothers were recruited during pregnancy and interviewed regarding methamphetamine use. Women in the exposure group used methamphetamine at least twice per month during pregnancy, while control mothers did not use methamphetamine. MRI scans were acquired within the first postnatal month. Anatomical images were processed using FreeSurfer and subcortical and cerebellar structures manually segmented with Freeview. Volumes were regressed with methamphetamine exposure (days/month of pregnancy) and related confounding variables, including total brain volume, gestational age at scan, exposure to cigarette smoking and infant sex. Diffusion data were processed with FSL, and diffusion tensors and tensor parameters determined using AFNI. Probabilistic tractography defined white matter connections between target regions. For the first analysis, five major white matter networks (commissural, and bilateral projection and association networks) were defined between spherical targets. For the second analysis, regions traced in the anatomical study were used as targets. Averaged DTI parameters were then calculated for each connection, and multiple regression analysis determined associations between DTI parameters and methamphetamine exposure at network level and in the individual connections. Methamphetamine exposure was associated with reduced caudate nucleus volume bilaterally, and in the right caudate following adjustment for confounders. Exposure was associated with reduced fractional anisotropy in all major white matter networks, and in individual connections within the limbic meso-cortico-striatal circuit. Exposure was associated with increased radial diffusivity in a subset of these. These results support findings in older children of methamphetamine-induced neurostructural damage, and demonstrate that such effects are already measurable in neonates. Corticostriatal circuit changes may underlie the impaired executive function observed in prenatally exposed children, and suggest a specific mechanism of damage in dopaminergic-related circuits that is consistent with the neurotoxic actions of methamphetamine.
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Characterizing the Directivity Effect Using Earthquake Simulations: the Influence of Source ParametersRamadan, Fatme 05 1900 (has links)
We investigate the influence of rupture complexity on directivity effects. We consider, in particular, how variations in the hypocenter location, the slip distribution and the rupture speed affect the amplitudes of near-field directivity pulses. To that end, we generate a suite of 15 bilateral-rupture models for an Mw 7 event and simulate the corresponding velocity waveforms at a number of sites in the vicinity of the fault. To quantify the influence of the hypocenter location and the rupture speed, we rely on a measure of the isochrone velocity on the fault along a path we term the “closest path”. Our simulations reveal that the peak amplitudes of the directivity pulses largely correlate with the isochrone velocity and that both increase with increasing rupture speed. We also examine the effect of the slip distribution and conclude that the presence of a region of high slip along the “closest path” leads to the amplification of the directivity pulse. Our findings primarily serve to inform empirical ground motion models on the rupture parameters of relevance to directivity.
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Production Pipelines for Creating a Cinematic Digital Matte PaintingShelton, Maggie 01 May 2021 (has links)
This writing covers concepts in the creation of a cinematic scene in digital matte painting. Digital matte painting is a visual effects process of the modern version of traditional matte painting, in which the artist paints several backgrounds to add to a scene. The digital artist uses software to paint, apply photo-bashing techniques, and/or utilize 3D models to create an exterior or interior environment. This scene incorporates 3D geometry in Autodesk Maya, brought to life through texturing and in-software lighting and animated cameras. The finalized scene includes color correction and additional visual effects.
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Dose Tolerance and Pharmacokinetic Studies of L (+) Pseudoephedrine Capsules in ManDickerson, Janet, Perrier, D., Mayersohn, M., Bressler, R. 01 July 1978 (has links)
Dose tolerance and pharmacokinetic studies of pseudoephedrine sustained action capsules were performed in thirty-three adult male subjects who received either 120 mg or 150 mg capsules every twelve hours for seven consecutive days in a double-blind parallel design study. Although only one subject in the 150 mg group was discontinued prematurely from this study, a large number of side effects typical of CNS stimulation were seen. A placebo effect might account for a portion of these complaints, however symtoms evaluated as being due to drug were significantly more severe and persistent in the 150 mg group. Pulse rates showed a persistent and significant increase while systolic and diastolic blood pressure fell from the baseline values in both groups. A pharmacokinetic analysis of the pseudoephedrine plasma concentration-time data provided estimates of half-life and the volume of distribution/availability ratio. The values obtained were in good agreement with values reported by others. Half-life was not influenced by urine pH probably as a result of the narrow range of urine pHs observed in the subjects. Calculations of relative bioavailability suggest that the 120 mg capsule formulation has a 30% greater bioavailability compared to the 150 mg capsule.
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Wealth Effects of Foreign Expansion by U.S. BanksWaheed, Amjad, Mathur, Ike 01 January 1995 (has links)
The effects of foreign expansion on the market values of U.S. banks (USBs) are examined in this study. The results show that shareholders of USBs experience significant abnormal returns of -0.17 percent when banks announce foreign expansions. Abnormal returns are insignificant when the announced mode of expansion is through a representative office, are significantly positive for announcements related to branches, and are significantly negative when the announced mode of expansion is through formation of a joint venture or a subsidiary, or through an acquisition. Abnormal returns are significantly negative when banks announce expansion into developed countries, and are significantly positive when announcements relate to risky developing countries. Post-announcement changes in the total variance of returns and in the unsystematic risk of USBs are inversely related with abnormal returns. Higher wealth effects are associated with higher levels of prior overseas experience.
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Career Interrupted for What Reason? Job Interruptions and Their Wage EffectsHayter, Jill K. 01 January 2014 (has links)
This paper examines whether controlling for the type of career interruption has different effects on men's and women's wages. One argument for the persistence of the gender wage gap is that previously researchers have used poor measures of experience to estimate men's and women's wages. This paper extends the career interruption literature by estimating men's and women's wages including controls for both the type and timing of interruptions. Findings show similar wage effects for men's and women's wages while controlling for the type of interruption. These results are consistent with the basic human capital model, but are inconsistent with previous empirical research.
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Examination of the Causal Effects Between the Dimensions of Service Quality and Spectator Satisfaction in Minor League BaseballKoo, Gi Y., Hardin, Rob, McClung, Steven, Jung, Taejin, Cronin, Joseph, Vorhees, Clay, Bourdeau, Brian 01 January 2009 (has links)
Sports organisations must continuously assess how better to meet or exceed consumer expectations and perceptions of their experience in order to maintain and increase the number of spectators and loyal fans attending their sporting events. This study aims to enhance our understanding of which characteristics of a service attribute will best define its quality and impact on spectator behaviour by understanding the causal relationship between perceived service quality (PSQ) and satisfaction.
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An Investigation into the Effects of Humor and Laughter on Depressive SymptomologyGoodson, Jason Talley 01 May 2001 (has links)
The current study was designed to test the theory that daily exposure to humorous material would reduce depressive symptoms. Thirty-eight undergraduate students endorsing depressive symptoms were randomly assigned to either a humor or comparison group. Dependent variables were scores on the Beck Depression Inventory, the Social Activities Scale from the Interpersonal Events Schedule, and the Positive and Negative Daily Affect Schedule. The humor group intervention consisted of take-home videotaped recordings of humorous materials. The comparison group intervention consisted of take-home video taped recordings of educational materials with motivational themes. Results indicated that subjects in both groups exhibited significant reductions in depressive symptoms. However, subjects in the humor group showed significant increases in social activities and daily affectual gains, while the comparison group subjects showed no such changes. Plausible reasons for the current findings as well as implications are discussed.
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The Effects of Stochastic Water Availability on Water Allocations in UtahGerstl, Gustavo A. Martinez 01 May 1982 (has links)
A methodology to estimate stochastic surface water flows was developed and applied to a case study area using chance constrained programming model. The results were analyzed as to the effects on different areas of production in Utah.
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Measurement of the Economic Effects of Trade Liberalization Policy in TaiwanHuang, Shu-Lan 01 May 1992 (has links)
Since the conclusion of world War II, Taiwan, the Republic of China (ROC), has developed into an industrialized country following a long period of severe inflation. Taiwan has produced a successful example of economic development through export expansion. Exports and imports of Taiwan increased from approximately 10 percent of the gross national product (GNP) in the 1950s to more than 45 percent in the 1980s. The role of Taiwan's foreign exchange rates and traderelated policies on exports and imports was examined in this study.
Trade-related policies implemented by the government of ROC were documented from 1950 to 1980 by categorizing the past 30 years into import substitution, export promotion, external shocks, and the 1980s trade liberalization periods. In
addition, this study analyzed quarterly import and export data from 21 sectors between 1981 and 1991 to measure the effects of changes on the exchange rate. variables included in the regression analysis were GNP of Taiwan and exchange rate for import demand functions and GNP of the U.S. , export price index in Taiwan and Korea, and exchange rate for the export demand function. Partial auto- correlation functions were estimated and examined for 21 export and import commodity groups to determine the appropriate number of lags in the demand function. In sectors in which regressions were found to be significant, an econometric partial adjustment model was used for estimating short- and long-run exchange rate elasticities.
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