Electronic Theses and Dissertations (2010 - Present)

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The University of Houston Libraries collect and make publicly available all electronic theses and dissertations (ETDs) produced in UH graduate and PhD programs through the UH institutional repository. ETDs become available after the student submits them to the UH Graduate School, the document is approved by all appropriate parties, and any embargo on the document expires.

Collection Scope

UH Libraries began publishing ETDs from several UH Colleges in 2010. As of Summer 2014, all UH Colleges that require a thesis or dissertation for graduation began submitting these documents in electronic format. Below is a list of UH Colleges that currently participate in the ETD program and their coverage dates in this repository.

UH College	Coverage Dates
C.T. Bauer College of Business	2010-Present
Cullen College of Engineering	2012-Present
Conrad N. Hilton College of Hotel and Restaurant Management	2015-Present
College of Education	2010-Present
College of Liberal Arts and Social Sciences	2012-Present
College of Natural Sciences and Mathematics	2012-Present
College of Optometry	2010-Present
College of Pharmacy	2010-Present
College of Technology	2012-Present
K. G. McGovern College of the Arts	2016-Present
G. D. Hines College of Architecture & Design	2016-Present
Graduate College of Social Work	2012-Present

Additional Information

Online access for content outside these coverage dates may be available electronically through ProQuest.
Note: As of Fall 2017, all theses and dissertations produced at UH will be submitted to ProQuest. Additionally, some UH Colleges have contributed content to ProQuest at different periods of time in the past.
For print theses and dissertations found outside these coverage dates, please consult UH Libraries’ catalog.
Additional information on submitting ETDs can be found at the UH Graduate School.

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Pragmatism, Patronage, Piety and Participation: Women in the Anglo-Norman Chronicles
(2008-05) O'Neal, Amy Michele; Vaughn, Sally N.; Patterson, Catherine F.; Orr, Patricia R.; Moretta, John A.
This dissertation examines the chronicles written in England and Normandy in the eleventh and twelfth centuries and explores how the writers of these histories perceived women. This study is meant to illuminate the lives of the women in the Anglo-Norman chronicles at every stage of life. While many modern books have addressed medieval women, they have attempted to deal with women more generally, looking at many areas and societies over hundreds of years. Other modern historians have focused on a few select women using evidence from the same Anglo-Norman chronicles used in this study. These historians, often times unintentionally, portray their subjects as extraordinary; this is simply not the case. Women like Adela of Blois, the Empress Matilda, and Queen Edith Matilda were the rule not the exception. The Anglo-Norman authors illuminate the lives of women at every stage of life and in every order of society. The chroniclers describe women who were wise and gave good advice, who were pious and showed it through patronage of the Church, and who were very active in society. This is their history.
The mechanisms of chronic nadolol treatment on the regulation of bronchial tone in a murine model of asthma
(2008-08) Lin, Rui; Bond, Richard A.; Bond, Richard A.; Knoll, Brian J.; Pedemonte, Carlos H.; Cahill, Gregory M.; Moore, Robert H.
Statement of the problem: Using a murine model of asthma, chronic beta blocker treatment was found to improve airway hyperresponsiveness (AHR). This finding completed a paradigm shift in the treatment of asthma using β adrenoceptor (AR) ligands, which was an analogy of the paradigm shift that occurred in congestive heart failure. Therefore, we hypothesized that chronic beta blocker treatment altered the cellular signaling modulating airway smooth muscle tone. Procedure or methods: Radioligand binding assays were used to measure β AR number and further identify the subtype of β AR regulated by chronic beta blocker treatment. To evaluate the effect of chronic nadolol treatment on Gs signaling pathways, cAMP accumulation in the lung homogenates was measured by direct enzyme immunoassay; the cAMP-PKA dependent signaling was evaluated by isoproterenol induced tracheal relaxation; Gs, GRK2, GRK3, PDE4D and β arrestin 2, important proteins regulating the Gs signaling and playing important roles in lung physiology were measured by immunoblotting. To evaluate the effect of chronic nadolol treatment on Gi and Gq signaling pathways, Gαi3, Gαi2, Gq, GRK5, PLCβ1, PKCα were also measured by immunoblotting. To evaluate the effect of chronic nadolol treatment on arachidonic acid metabolism, cysteinyl leukotrines were measured in bronchoalveolar lavage fluid (BALF), while cPLA2, COX2 and 5-LO were also measured by immunoblotting. In addition, β2 AR knockout mice were treated with the same protocol as the wildtype mice to confirm that the effects of chronic nadolol treatment on PDE4D, Gαi3 and PLCβ1 were β2 AR dependent. Results: Chronic beta blocker treatment increased β2 AR density and decreased PDE4D expression. Although chronic beta blocker treatment showed no effect on cAMP-PKA dependent airway smooth muscle relaxation, the regulation of Gi expression and Gi signaling in airway smooth muscle were found to be altered with chronic nadolol treatment. Also, chronic nadolol treatment decreased PLCβ1 expression and PKCα, 5- LO translocation. While a reduction in AHR, mucous metaplasia, and inflammatory cell counts in bronchoalveolar lavage fluid (BALF) was observed in wildtype mice, chronic nadolol treatment had no effect on PDE4D, Gi3 and PLCβ1 expression in β2 AR null mice. Conclusion: Chronic nadolol treatment decreased airway tone in a murine model of asthma by decreasing cAMP breakdown and Gi, Gq signaling. These effects are possibly dependent on its chronic blockade of β2 AR.
Impacts of Size on Pharmacokinetics and Biodistributions of Mebendazole Nanoformulations in Mice and Rats
(2008-08) Qi, Yulan; Chow, Diana Shu-Lian; Bates, Theodore R.; Hu, Ming; Liang, Dong; Tam, Vincent H.
Mebendazole (Mbz), a poorly water-soluble anthelminthic drug, possesses siginificant antineoplastic effects in both in vitro and in vivo studies. Microemulsions (PM1 37nm and PM2 478 nm) and nanosuspensions (NS-167nm, NS-400nm, NS-700nm and NS-1700nm) of various sizes, and a cosolvent formulation have been developed for the potential parenteral delivery of Mbz. The purpose of the study was to investigate the role of physical nature and particle size of the nanoformulations on Mbz dispositions by comparatively establishing their pharmacokinetics and biodistribution profiles in athymic nude mouse and rat models. In vitro release studies of Mbz from the cosolvent and nanosuspensions was slower in rat plasma than in PBS, and the initial rates and extent of release from NS-167nm in PBS and rat plasma were significantly greater than those of NS-700nm and NS-1700nm in PBS, and that of NS-1700nm in rat plasma. Mbz from cosolvent and nanoformulations followed a two-compartment model after administration. PM1 and PM2 exhibited similar plasma pharmacokinetics of cosolvent in mice, with only Cmax/dose, k10 and k21 different from those of cosolvent. However, the tissue distribution patterns of PM1 and PM2 were distinct from that of cosolvent. PM1 and PM2 displayed very high AUCs/dose in lung, 6 to 7 times of that of cosolvent. The t1/2 of Mbz in lung from PM1 was longer than those of cosolvent and PM2. Different from the cosolvent, Mbz nanosuspensions exhibited very high and prolonged drug concentrations in liver and spleen due to the reticuloendothelial system (RES) uptake. The large-sized NS-1700nm displayed larger Vss and V2 (1.45 and 1.35 L) than NS-167nm (0.85 and 0.79 L) in mice. Biodistributions of Mbz from cosolvent, NS-167nm, NS-400nm, NS-700nm, and NS-1700nm in rats were comparatively established. The patterns of nanosuspensions in rats were similar to those in mice. The half-life of total Mbz in liver for NS-700nm was longer than those for NS-167nm and NS-400nm. The half-life of total Mbz in spleen for NS-400nm was longer than that for NS-167nm. The elimination half-lives of parent Mbz in liver and spleen of rats increased as particle size increased. Three-compartment pharmacokinetic models described the relationship between plasma and lung concentrations of Mbz after i.v. administration of PM1 and PM2 was successfully developed and validated, enabling the prediction of lung concentration profiles based on measured plasma concentrations. Human plasma pharmacokinetic parameters (CL, Vss, t1/2, α, and t1/2, β) for Mbz cosolvent, PM1 and PM2, as well as NS-167nm and NS-1700nm were predicted by allometric scaling. The PK parameters predicted for human from Mbz microemulsions of various sizes between PM1 and PM2 were similar, while distinct between NS-167nm and NS-1700nm. Our results demonstrated that the droplet/particle size of the nanoformulations had profound effects on Mbz dispositions in mice and rats, that might be critical in optimizing cancer therapy.
Exploring a Broader View of Technology Acceptance
(2010-05) Steel, Douglas; Chin, Wynne W.; Johnson, Norman A.; Penney, Lisa M.; Schwarz, Andrew H.
The primary aim of this dissertation is to establish the generalizability of the scale items used to measure 5 psychological acceptance constructs proposed by Schwarz and Chin (2007). While an initial test of validity and reliability was established by Schwarz (2003) using covariance-based structural equation modeling, a stronger test was performed to establish the generalizability of the items through a series of multigroup invariance tests. Having used 3 new independent data sets, we present the results of the combinatorial analyses of 3 pairwise comparisons of the data sets as well as a test comparing all 3 data sets simultaneously. Both confirmatory factor models and structural models were applied to examine whether item measures are identically reliable and whether the relationships among these 5 constructs also remain the same. Structurally, two models incorporating these 5 constructs were applied to predict an overall general acceptance construct and the construct of infusion. While the nomological relationships among these acceptance constructs varied as expected, the correlations and item loadings remain invariant. Therefore, the results answer the questions: (1) Can the acceptance constructs proposed by Schwarz and Chin be captured by reliable and accurate measures? (2) Are these constructs distinct from one another? and (3) Do they act similarly in different contexts? Finally, to provide a platform for more research on workplace outcomes, this research explores the notion of technology infusion, an important form of usage. Given that the 5 psychological acceptance constructs have predictive value toward infusion, we establish a means for further study of the concept.
Correspondence of directly and indirectly measured built environment attributes and physical activity adoption among African American and Hispanic or Latina Women
(2010-05) McAlexander, Kristen; Lee, Rebecca E.; Layne, Charles S.; O'Connor, Daniel P.; Rifai, Hanadi S.
Ethnic minority women report poorer health outcomes and attitudes and are more vulnerable to overweight and/or obesity compared to Caucasian women. Epidemiological studies and ecologic models of health behavior suggest that built environmental factors are associated with health behaviors, like physical activity (PA), that can help to prevent obesity and its many comorbidities. Despite growth and development in this field of research, many questions remain about the relationship between the built environment and perceptions about the built environment, and whether accurate perceptions are important for PA adoption. The objectives of the study were (1) to measure the concordance of directly measured and indirectly measured neighborhood attributes and (2) to determine the correlates of the concordance between directly and indirectly measured built environment attributes among separate samples of African American and Hispanic or Latina women (3) to determine whether there is an association between concordance and PA adoption among African American and Hispanic or Latina women. Community dwelling African American and Hispanic or Latina women participating in an ongoing HIP study self-reported their environmental perceptions at baseline (T1). In order to assess longitudinal PA levels and explore ethnic differences of neighborhood perceptions, we compared objectively measured neighborhood attributes with self-reported neighborhood attributes for African American and Hispanic or Latina women. Participants’ (N=409) average BMI was classified as obese (M BMI=34.5 kg/m2, SD=7.9) and the mean body fat percentage was 42.8% (SD=7.1). BMI, body fat percentage, PA and ethnicity were not significantly associated with any built environment attribute, and no multinomial regression model significantly predicted indirectly measured built environment attributes. Repeated measures analyses suggested no significant relationships between any built environment attribute concordance value and PA adoption for total self-reported or objectively measured PA. Self-reported PA significantly increased over time (F(1,184)=7.82, p=.006), and this increase did not vary by ethnicity or any built environment attribute concordance value. Being less familiar with certain built environment attributes may not be associated with PA adoption. In an effort to promote PA, community leaders and investigators must consider the complex associations between built environment attribute concordance and PA adoption, particularly among the vulnerable population of minority women.
Mechanisms of Exercise-Mediated Restoration of Renal Dopamine D1 Receptor Function in Aging
(2010-05) George, Liza; Lokhandwala, Mustafa F.; Asghar, Mohammad; Eikenburg, Douglas C.; Lawler, John M.; Martinez, Daniel A.
Renal dopamine plays a pivotal role in the maintenance of sodium homeostasis and blood pressure. Dopamine by activating D1 receptors (D1R) and inhibiting sodium transporters, Na, K-ATPase and Na, H exchanger, in renal proximal tubules (RPTs) promotes sodium excretion and thus maintains sodium homeostasis. The aging process alters vital organ functions including kidney function. Our previous studies have demonstrated a diminished natriuretic response to dopamine in aging kidneys. Age-associated oxidative stress is reported to increase D1R serine-phosphorylation via PKC/GRK-2 pathway. This causes D1R G-protein uncoupling and the inability of D1R agonist SKF-38393 to inhibit Na, K-ATPase in RPTs and subsequently promote sodium excretion in old rats. Exercise improves physiological function and reduces mortality. However, it is not known whether exercise reverses the age-related decline in D1R function. Therefore, the objective of this project was to determine if exercise could restore renal D1R function. The first part of the project studied the effect of exercise on natriuretic response to D1R agonist SKF-38393, revealing an increased sodium excretion with SKF-38393 in exercised compared to sedentary aged rats indicating restoration of D1R function. The second part studied the molecular events in RPTs. The study revealed that exercise mediated antioxidant enzymes over-expression, reduction in oxidative stress, decrease in PKC activity and D1R serine-phosphorylation and increase in D1R-G protein coupling and inhibitory effect of SKF-38393 on Na, K-ATPase in aged rats. Also, these events were associated with increased activation of transcription factors NF-κB and Nrf-2 in exercised aged rats. The third part of the project elucidated a causative role of NF-κB and/or Nrf-2 in antioxidant enzymes expression and subsequent protection from oxidative stress-induced D1R dysfunction in NF-κB and/or Nrf-2 transfected HK-2 cells. The study showed that NF-κB and/or Nrf-2 increased antioxidant enzyme levels and ability of SKF-38393 to stimulate 35S-GTPγS binding (index of D1 receptor function) even in the presence of the oxidant H2O2. Taken together, these studies demonstrate that the mechanism of exercise mediated decrease in oxidative stress and restoration of renal D1R function in aging involves exercise-induced increase in antioxidant defense via NF-κB and/or Nrf-2.
THE PROTECTIVE EFFECTS OF CHRONIC CAFFEINE TREATMENT ON THE COGNITIVE FUNCTION AND SYNAPTIC PLASTICITY IN ACUTE SLEEP DEPRIVATION
(2010-05) Alhaider, Ibrahim; Alkadhi, Karim A.; Lau, Yuen-Sum; Hussain, Tahir; Leasure, J. Leigh; Aleisa, Abdulaziz M.
Study objectives: Accumulating evidence has shown that caffeine and sleep deprivation have opposing effects on learning and memory; therefore, this study was undertaken to provide a detailed account of the effect of chronic, low-dose caffeine treatment on the deleterious effects of sleep loss on hippocampus-dependent learning and memory. Experimental design: We investigated the effects of chronic (4 weeks) caffeine treatment (0.3 g/l in drinking water) on memory impairment in acutely (24 hr) sleep-deprived rats. Sleep deprivation was induced using the modified multiple platform model. The effects of caffeine on sleep deprivation-induced hippocampus-dependent learning and memory deficits were studied using three approaches: learning and memory performance in the radial arm water maze task; electrophysiological recordings in the Cornu Ammonis (CA1) and dentate gyrus (DG) regions of the hippocampus; and western blot analysis to measure the levels of memory- and synaptic plasticity-related signaling molecules. Results: Our results showed that chronic caffeine treatment prevented impairment of hippocampus-dependent learning, short-term memory and early phase- long-term potentiation (E-LTP) of the CA1 and DG areas in the sleep-deprived rats. In correlation, caffeine treatment prevented a sleep deprivation-associated decrease in the basal levels of phosphorylated calcium/calmodulin-dependent protein kinase II (P-CaMKII) and brain-derived neurotrophic factor (BDNF). In addition, caffeine treatment of sleep-deprived rats increased the levels of P-CaMKII during the expression of E-LTP. The results also showed that chronic caffeine treatment prevented the impairment of long-term memory and late phase-LTP (L-LTP) in the CA1 and DG regions of the sleep-deprived rats. Additionally, caffeine treatment prevented a sleep deprivation-associated decrease in the basal levels of the phosphorylated cAMP response element binding protein (P-CREB) as well as total CREB. Treating sleep-deprived rats chronically with caffeine enables multiple high frequency stimulation to increase the levels of P-CREB during L-LTP expression. Conclusions: The results suggest that long-term use of a low dose of caffeine protects against the harmful changes in the basal levels of P-CaMKII, P-CREB and BDNF associated with sleep deprivation and as a result contributes to the revival of hippocampus-dependent learning and memory as well as LTP in the CA1 and DG regions.
Relationship Between Flavonoid Structure And Phase-II Metabolism
(2010-05) Singh, Rashim; Hu, Ming; Chow, Diana Shu-Lian; Tam, Vincent H.; Ghose, Romi; Briggs, James M.
Objective: The overall objective is to develop structure-metabolism relationships (SMRs) between UGTs and flavonoids for predicting glucuronidation of flavonoids. The goals of this research project were to: 1) identify the major UGT isoform(s) contributing to the glucuronidation of flavonoids and predicting the major organ of metabolism; 2) establish the substrate-selectivity and regiospecificity of these major UGT isoform(s); 3) develop the in silico prediction models for UGT 1A8 and UGT1A9 using pharmacophore and 2-D/3-D QSAR modeling techniques; 4) study the effect of change in backbone on the disposition of flavonoids in Caco-2 cells; 5) study the rate-limiting role of efflux transporters in the disposition of flavonols in Caco-2 cells; and 6) study the regiospecific disposition of flavones in Caco-2 cells. Method: For objectives 1 and 2, in vitro recombinant human UGT isoforms glucuronidation model was used. For objective 3, in silico pharmacophore and 2-D/3-D QSAR modeling was used along with in vitro glucuronidation intrinsic clearance values in recombinant human UGT isoforms. For objectives 4, 5 and 6, intact Caco-2 cell monolayers was used as the transport model, and Caco-2 cell lysate was used for measuring glucuronide formation rates. Results: 1) To identify the major UGT isoform(s) contributing to the glucuronidation of flavonoids and predicting the major organ of metabolism, we found that flavonoids were mainly glucuronidated by UGT1A1, 1A8 and 1A9 at the substrate concentration of 2.5, 10 and 35μM. 2) To establish the substrate-selectivity and regiospecificity of these major UGT isoform, we found that UGT1A1 showed no regiospecificity for glucuronidating any position, whereas, UGT1A8 and UGT1A9 showed either dominant, preferred or weak regiospecificity for 3-O or 7-O position, depending on the structure of the compound. In general, the addition of hydroxyl group at C-4' reduced, whereas the addition of hydroxyl group at C-5 and/or C-7 improved the rates of glucuronidation of flavonoids by UGT1A8 and 1A9. On the other hand, the rates of glucuronidation by UGT1A1 reduced as number of hydroxyl group in the structure increased. 3) To develop the in silico prediction models for UGT1A8 and UGT1A9 using pharmacophore and 2-D/3-D QSAR modeling techniques, we found that pharmacophore-based semi-quantitative SMR models for UGT1A9 with >75% predictive ability could be developed. But neither semi-quantitative SMR models for UGT1A8 nor the quantitative SMR models for UGT1A8 and UGT1A9 could be successfully developed. 4) To study the effect of change in backbone on the disposition of flavonoids in Caco-2 cells, we found that the change in backbone impacts the excretion of flavonoid sulfates more significantly than the excretion of their glucuronides except for genistein. 5) To study the rate-limiting role of efflux transporters in the disposition of flavonols in Caco-2 cells, we found that excretion of flavonol glucuronides in Caco-2 cells were not limited by efflux transporters and glucuronides of flavonols showed basolateral preference in their excretion. 6) To study the regiospecific conjugation of flavones in Caco-2 cells, we found that both glucuronidation and sulfation of flavones mainly happened at hydroxyl group at C-7 position. Conclusion: UGT1A9, UGT1A8 and UGT1A1 are the most important isoforms that can glucuronidate vast majority of tested flavonoids. Based on published UGT isoform expression pattern in human liver and intestine, they should serve as the major first-pass metabolism organs for flavonoids. UGT1A8 and UGT1A9 showed regiospecificity for 3-O or 7-O position, depending on the structure of the compound, whereas UGT1A1 showed no regiospecificity. Also, the addition of hydroxyl group at C-4' reduced, whereas the addition of hydroxyl group at C-5 and/or C-7 improved the rates of glucuronidation of flavonoids by UGT1A8 and 1A9, with rare exceptions. In contrast, the rates of glucuronidation by UGT1A1 reduced as number of hydroxyl group in the structure increased. Isoform-specific semi-quantitative Pharmacophore-based 3-D SMR prediction models could be developed for UGT1A9 with the predictive ability of more than 75%, but more efforts are needed to develop better quantitative models of prediction. We also probed the SMR experimentally using the Caco-2 model, and the results showed that the excretion of glucuronides was impacted more by the change in number and position of hydroxyl group in the flavonoid structure than changes in backbone. The excretion of glucuronides of flavones but not flavonols is rate-limited by efflux transporters. Future SMR research will incorporate more experimentally derived information to develop better models to predict glucuronidation of flavonoids in humans.
CHRONIC STRESS REVEALS COGNITIVE IMPAIRMENT IN A SUBTHRESHOLD AMYLOID-BETA MODEL OF ALZHEIMER’S DISEASE
(2010-05) Tran, Trinh T. 1982-; Alkadhi, Karim A.; De Biasi, Mariella; Lau, Yuen-Sum; Rea, Michael A.; Salim, Samina
Although it is generally accepted that Aβ contributes to the pathogenesis of Alzheimer's disease (AD), other factors that impact the severity and time of onset of the disease are not well known. Aside from genetic factors, environmental factors, such as stress, may also play a critical role in the manifestation of AD. Epidemiological studies indicate that individuals suffering from chronic stress are at an increased risk for developing AD. The present study investigated the effect of chronic psychosocial stress in an at-risk, subthreshold Aβ (subAβ) rat model of AD by three techniques: learning and memory tests in the radial arm water maze, electrophysiological recordings of long-term potentiation (LTP) and long-term depression (LTD) in anesthetized rats, and immunoblot analyses of learning- and memory-related signaling and AD-related molecules. Chronic psychosocial stress was induced using a rat intruder model. The subAβ rat model of AD was induced by continuous i.c.v. infusion of 160 pmol/day Aβ1-42 via a 14-day mini-osmotic pump. Behavioral tests, electrophysiological recordings, and molecular analyses showed that subAβ rats were not significantly different from control rats, thus validating this model as an at-risk model of AD without phenotypic characteristics or cognitive deficits commonly associated with AD. However, chronically stressed subAβ-infused rats showed significantly greater impairment of cognitive functions and synaptic plasticity than that caused by stress alone. Molecular analyses of essential signaling molecules showed that animals subjected to stress have reduced basal levels of p-CaMKII, decreased p-CaMKII/CaMKII ratio, and increased basal levels of calcineurin. The infusion of subAβ into the cerebral ventricle of chronically stressed rats also decreased basal levels of p-CREB, total CREB and BDNF and increased basal levels of BACE. Furthermore, multiple high frequency stimulation failed to increase levels of p-CREB and BDNF during the late-phase of long-term potentiation. However, paired pulse stimulation produced a decrease in levels of BDNF during long-term depression in the stress/subAβ animals. Together, the results of our behavioral, electrophysiological, and molecular studies suggest that prior and concomitant exposure of subAβ-infused rats to chronic stress intensify the severity of stress-induced cognitive and synaptic plasticity deficits. Thus, chronic stress may accelerate the impairment of learning, memory, and synaptic plasticity in individuals “at-risk” for AD.
Gender difference affects absorption and disposition of soy isoflavones in rats
(2010-05) Kulkarni, Kaustubh 1977-; Hu, Ming; Tam, Vincent H.; Yu, Rong; Pownall, Henry J.; Ghose, Romi
Female Sprague-Dawley rats showed 2-fold higher total oral bioavailability (14C genistein) than male rats. Due to experimental limitations of measurement of radioactivity count, the absolute oral bioavailability of genistein and its phase II metabolites is still unknown. In this study, gender-dependent differences in oral bioavailability of genistein (20mg/kg) in male and female SD rats were determined. Female rats showed significantly higher (2 fold) oral bioavailability of total genistein in female than in male rats. The gender difference observed was due to significantly higher (4 fold) plasma genistein glucuronide concentrations in female than in male SD rats. These results were consistent with the gender-dependent differences in genistein absorption and disposition in rats using rat intestinal perfusion model. In perfusion model, female rats showed significantly higher biliary excretion of genistein glucuronide than in male rats, suggesting higher enterohepatic recycling in female rats as primary mechanism of action for higher oral genistein bioavailability in female than male rats. We also identified that hormonal changes as the result of estrus cycle play an important role in genistein absorption and disposition in female rats. We further compared the oral bioavailability of genistein in control female and female ovariectomized SD rats to determine if the difference in gender was due to differences in female sex hormones produced by ovaries. To our surprise, female ovariectomized rats showed higher (2.5 fold) oral bioavailability of total genistein than in control female rats, including higher plasma AUC of genistein (2 fold), genistein glucuronide (3 fold), and genistein sulfate (25 fold). Interestingly, exogenous dose of estrogen did not reverse any of bioavailability enhancement effects shown in female ovariectomized rats. The mechanisms responsible for the higher bioavailability of genistein in female ovariectomized rats remain unknown and require further investigation. In conclusion, genistein displayed substantial and significant gender-dependent differences in oral bioavailability of total genistein. Moreover, removal of sex hormones produced in ovary significantly impaired genistein metabolism in female rats, and the effect was not reversed by exogenous estrogen administration.
Motivational beliefs, ethnic identity, and sense of belonging: Relations to school engagement and academic achievement
(2010-05) Sha, Ting Ling; Yu, Shirley L.; Wiesner, Margit F.; Wolters, Christopher A.; Watson, Margaret
Students’ motivational beliefs, sense of belonging, and ethnic identity were examined in relation to effort, persistence, procrastination, school attendance, and academic achievement. A total of 589 seventh and eighth graders completed a self-report survey assessing motivational belief variables (academic self-efficacy; Midgley et al., 2000; value of academic success; Fuligni, Witkow, & Garcia, 2005; mastery-approach goal orientation; Midgley et al., 2000, mastery-avoidance goal orientation; Elliot & McGregor, 2001; performance-approach goal orientation and performance-avoidance goal orientation; Midgley et al., 2000), sense of belonging variables (acceptance, belonging, rejection; Hagborg, 1994; perception of teachers’ opinions), ethnic identity variables (affirmation, belonging, and commitment and exploration and behaviors; Roberts et al., 1999), and school engagement variables (effort, persistence, procrastination; Wolters, 2004; attendance). Results from the hierarchical multiple linear regressions indicated that feelings of rejection, the adoption of mastery-avoidance goal orientation, and the adoption of performance-avoidance goal orientation were negative predictors of effort and persistence. Perceptions of teachers’ opinions, academic self-efficacy, value of academic success, mastery-approach goal orientation, and performance-approach goal orientation were positive predictors of effort. Academic self-efficacy, value of academic success, and mastery-approach goal orientation were positive predictors of persistence. Rejection, mastery-avoidance goal orientation, performance-approach goal orientation, and performance-avoidance goal orientation were positive predictors of procrastination, while value of academic success and mastery-approach goal orientation were both negative predictors of procrastination. Belonging and value of academic success were positive predictors of attendance, while mastery-avoidance was a negative predictor. Academic self-efficacy and attendance were positive predictors of overall language arts averages, overall academic averages, and reading achievement scores. Value of academic success was a positive predictor of student overall academic averages and reading achievement scores. However, mastery-approach goal orientation was a negative predictor of each of the academic outcome variables. Persistence (positively) and procrastination (negatively) were also predictive of overall language arts averages and overall academic averages. Affirmation, belonging, and commitment was a positive predictor of reading achievement scores, yet performance-approach goal orientation was a negative predictor of reading achievement scores. These results offer practical implications for educators, illustrating the importance of academic self-efficacy and value of school success on effort, persistence, and academic achievement.
MORPHOMETRIC HISTOPATHOLOGY OF THE PHYSIOLOGICALLY FIXED KERATOCONIC CORNEA
(2010-08) Mathew, Jessica 1978-; Bergmanson, Jan P.; Goosey, John D.; Leach, Norman E.; Miller, William L.; Twa, Michael D.; Rabinowitz, Yaron S.
Purpose: Clinically, keratoconus is a condition associated with corneal ectasia, thinning, steepening and scarring, and sometimes necessitates transplant surgery. Exactly where this corneal pathology starts, what structures are involved and what is lost in the thinning process is poorly defined in literature. The purpose of this study was to investigate the etiology, pathophysiology and the structural collapse leading to ectasia by utilizing a histopathological approach. Methods: A total of 15 surgically removed keratoconic corneas and 7 eye bank control corneas were used. The corneas were fixed in 2% glutaraldehyde in 80mM sodium cacodylate (pH 7.4, 320 to 340 mOsm/kg) and prepared for transverse sectioning with light (Olympus BX51 digital) and transmission electron microscopy (Jeol 100C, initially, and the Tecnai G2 12 twin). Serial electron micrographs were taken of the geometric center of normal corneas and the central cone region of keratoconic corneas. Montages were created for full stromal thickness lamellar counts and for assessment of the anterior limiting lamina (ALL)/stromal interface. Lamellar counts adhered to a specific set of criteria, while a morphometric approach was utilized to define the features of the ALL/stromal interface. The central cone and mid-peripheral regions of the keratoconic cornea were evaluated using light microscopy (LM) and larger anatomical and pathological structures were quantified with the aid of NIH image software. Results: The normal cornea contained 242+4 lamellae, while the keratoconic cornea averaged 319+105 but, if an extremely thinned keratoconic cornea was excluded, the average was 360+22. In the keratoconic cornea, the middle and, to a degree, posterior lamellae had broken up into smaller units. In the normal cornea, the ALL and stromal layers showed some shallow overlapping of <1µm in either direction. The anterior stromal lamellae were delicate and interweaved extensively. In central and peripheral LM assessments of the keratoconic cornea, the ALL was thinned or lost over 60% of the area examined and the thin anterior lamellae were absent. Anterior lamellae in central control cornea appeared, at intervals, to terminate surrounded by dense staining particles. This unreported stromal feature was termed electron dense formation and was not observed in the keratoconic cornea. The epithelial thickness varied greatly across the keratoconic cornea (14-92µm), while the epithelium in normal maintained a uniform thickness. Keratoconic specimens contained densely stained, distorted epithelial cells and in 58%, a grossly thickened basement membrane. Stroma in the normal cornea contained predominantly one cell type, the keratocyte, along with the occasional Schwann cell and neuron, but in keratoconus, other cells were present in areas where apparent stromal and ALL disassembling occurred. Conclusions: The keratoconic stroma had paradoxically 50% more lamellae than the normal and this was explained by the fragmentation of lamellae – not an actual increase in lamellae, but rather the breaking apart of lamellae, which has not been described elsewhere. The complete loss of anterior interweaving lamellae in the keratoconic corneas examined likely contributes to the thinning of the keratoconic corneas seen clinically. The terminating lamellae in the normal central cornea suggests that stromal lamellae do not span the full width of the cornea, which is in contradiction to existing literature. The present study reported a clear and well-defined epithelial contribution to pathological changes in keratoconus, but this work does not establish which layer - the epithelium or stroma – is affected first. The extensive destruction of ALL reported here is in contrast to previous statements in literature. It appears that the removal of ALL and anterior lamellae is accomplished by stromal cells that may have been recruited from outside the cornea. This morphometric, ultrastructural study has demonstrated the anterior focus of keratoconus and the epithelial involvement in the disease, all of which is of importance to contact lens practitioners and surgeons. The new knowledge on the normal human cornea, e.g. number of lamellae and anterior structural integration, generated by this work has multiple surgical and clinical applications. The loss and disintegration of lamellar structure in keratoconus appears to be an important factor in provoking ectasia and its accompanying devastating effect on vision.
Factor Structure and Validity of the Lesbian, Gay, and Bisexual Knowledge and Attitude Scale for Heterosexuals (LGB-KASH)
(2010-08) Summers, Bryce; Arbona, Consuelo; Burridge, Andrea Backscheider; Gaa, John P.; Backus, Margot
Heterosexual attitudes toward Lesbian, Gay, and Bisexual (LGB) individuals have become the focus of recent research as sexual minorities and allies have advocated for LGB human rights issues and have subsequently captured the attention of the media (Rimmerman, 2001, 2008; Rimmerman, Wald, & Wilcox, 2000). Multiple influences shape heterosexual attitudes including gender socialization, individual sexual identity exploration, religious beliefs, and systemic prejudicial attitudes (Altemeyer & Hunsberger, 2005; Kilanski, 2003; Worthington, Savoy, Dillon, & Vernaglia, 2002; Worthington, Becker-Schutte, & Dillon, 2005). Worthington, Dillon, and Becker-Schutte (2005) and colleagues proposed that heterosexual attitudes toward sexual minorities are one aspect of the individual's sexual identity that is comprised of several dimensions. Worthington et al. developed an instrument titled the Lesbian, Gay, Bisexual Knowledge and Attitude Scale for Heterosexuals (LGB-KASH) to assess the proposed dimensions of heterosexual attitudes toward LGB individuals. Results of confirmatory factor analyses with primarily white college students and adults in the Midwest identified five factors that were consistent with the proposed dimensions. These factors were labeled: hate (violent homonegativity; avoidance of LGB people); LGB knowledge; attitudes toward LGB civil right issues; religious conflict (ambivalent and negative attitudes caused by religious beliefs); and internalized affirmativeness (degree of comfort of having friends who are identified as LGB; feeling comfortable of having feelings of attraction towards the same-sex). The LGB-KASH's five dimensions correlated in the expected direction with scales assessing traditional homonegativity and religiosity. No other study was located that examined the factor structure and the validity of the LGB-KASH subscales. The purposes of the proposed study was to examine (a) the factor structure of the LGB-KASH with an ethnically diverse college sample, and (b) the relation of the LGB-KASH dimensions to scales assessing modern-homonegativity and religious fundamentalism. It was hypothesized that the LGB-KASH five-factor structure would be confirmed with ethnically diverse college students. It was expected that modern-homonegativity would correlate positively with the hate and religious conflict subscales, and correlate negatively with the LGB knowledge, LGB civil right and internalized affirmativeness subscales. It was expected that religious fundamentalism would correlate positively with the hate and religious conflict subscales, and correlate negatively with LGB knowledge, LGB civil right and internalized affirmativeness subscales. Spirituality experiences of participants were also assessed expecting to find that experiences of spirituality would be unrelated to LGB-KASH subscales. This study surveyed 701 heterosexual identified volunteer participants. Participants represented several major ethnic groups including African-Americans, Latino/a, Asian-Americans, and European Whites. The instruments that were used in the study include: a demographic questionnaire, the LGB-KASH, the Modern Homonegativity Scale (MHS; Morrison & Morrison, 2002), the Religious Fundamentalism Scale (RFS; Altemeyer & Hunsberger, 1992), and FACIT-Spirituality Scale (Peterman, Fitchett, Brady, Hernandez, & Cella, 2002). A confirmatory factor analysis was conducted with an oblique rotation using AMOS 17.0 to examine the factor structure of the LGB-KASH. Several indexes of fit were computed to assess how well the model fit the data including the chi-square, goodness-of-fit index (GFI), adjusted goodness-of-fit index (AGFI), comparative-fit index (CFI), root-mean-square residual (RMR), incremental fit index (IFI), parsimony comparative fit index (PCFI), and root-mean-square error of approximation (RMSEA). The CFA results indicated that the five factor-oblique model had a mediocre fit, and a comparable fit to the results found by Wort
Factors that infuence age of identification of children with autism and pervasive developmental disorder nos
(2010-08) Adelman, Chana; Kubiszyn, Thomas; Peters, Sarika; Wiesner, Margit F.; Schanding, G. Thomas, Jr.; Goodman, Gay
Early diagnosis of autism spectrum disorders (ASD) is crucial because early identification can lead to early intervention, which has been shown to improve the outcome of children diagnosed with ASD. This study explored the current mean age of diagnosis of Autism and Pervasive Developmental Disorder, NOS in the United States. Analysis of variance was employed to determine whether average age of diagnosis of children with Autism and Pervasive Developmental Disorder NOS differs in the four regions in the United States. Linear regression analyses were performed to determine which of the following factors predict age of diagnosis: the child’s ethnicity, whether the child has an older typically developing sibling, whether the child has an older sibling who had/has a developmental delay other than autism, whether the child has an older sibling who has been diagnosed with autism, whether the child was first diagnosed with another disorder, the type of first symptoms to cause concern, whether the child was referred to ECI, whether the child switched pediatricians, whether the child’s pediatrician conducted regular developmental screenings, whether the child’s pediatrician conducted a screening specific to autism, reaction of pediatrician if parent raised concerns regarding child’s development, whether the child was covered by health insurance, annual household income, and parents’ level of education. Potential participants were recruited with the assistance of the Interactive Autism Network (IAN) Research Database at the Kennedy Krieger Institute and Johns Hopkins Medicine in Baltimore, sponsored by the Autism Speaks Foundation. Participants were selected from a pool of participants who have registered with IAN, who have agreed to participate in autism research, and whose children met the study criteria. The potential participants were sent a recruitment letter via email by IAN research personnel, which included a link to the on-line survey. The study description and a link to the survey were also posted on the IAN Community Research Opportunities Bulletin Board. A sample size of 654 participants was used for data analysis. Current age of diagnosis in months of autistic disorder and PDD-NOS in the United States was 37.78, and SD=16.269. Due to violations of normality assumptions for age of diagnosis, a logarithm transformation was used (M=1.54 and SD=.166). Results of a one-way ANOVA indicated differences in age of diagnosis among the four regions in the United States F (3, 650) = 7.618, p=.01). Tukey’s post hoc comparisons of the groups indicated that the mean log base 10 age of diagnosis in the Midwest (M=1.59) was significantly later than in the Northeast (M=1.5152, p=.000) and South (M=1.5219, p=.000). Results of a Pearson Correlation indicated a significant negative correlation (r=-.409, n=654, p=.000) between date of birth and age of diagnosis, with later birthdays being associated with lower age of diagnosis. Regression results were statistically significant, F(25, 620)=7.549, p<.001, R2=.233. Having autistic older sibling/s, being referred to ECI, and having a pediatrician who performed an in-depth screening in response to parent concerns, were negatively correlated with the logarithm of age of diagnosis, while having first symptoms of non-autism specific behavioral difficulties, being given a non-ASD diagnosis prior to ASD diagnosis and switching pediatricians during first five years of life, were positively correlated with the logarithm of age of diagnosis.
Neuronal and Mitochondrial Protection in Chronic Parkinsonism
(2010-08) Patki, Gaurav; Lau, Yuen-Sum; Alkadhi, Karim A.; Eriksen, Jason; Le, Wei-dong; Widger, William R.
Among the several plausible neuropathological hypotheses underlying the progression of aging and neurodegenerative diseases such as Parkinson’s disease (PD), oxidative stress and mitochondrial damage have emerged as one of the attractive biochemical mechanisms. However, most of the past studies linking mitochondrial dysfunction to neuronal degeneration have been carried out in vitro or in acute in vivo studies. It is not known whether mitochondrial dysfunction is an immediate response to cytotoxic-inducing agents or is sustained as a long-term consequence of neuronal death. The purpose of our research was to first validate the chronic mouse model of Parkinson’s disorder (MPD), which has been developed and characterized by our laboratory as a suitable animal model for investigating neuronal and mitochondrial dysfunctions and then to examine the protective effects of endurance exercise and melatonin treatment on this model. Male, C57/BL retired breeder mice at 6-10 months of age were used in the present study. The aged chronic MPD was treated with of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) (15 mg/kg, s.c), twice a week for 5 weeks. MPTP was co-administered with probenecid (250 mg/kg, i.p), an adjuvant that is known to inhibit the peripheral and neuronal clearance of MPTP and potentiate the neurotoxicity of MPTP. The chronic MPD was previously shown to display neurochemical, histological, behavioral and pathological features resembling those of PD-like neurodegeneration lasting for at least 6 months. Six to twelve weeks after chronic MPTP treatment, aged mice showed sustained decrease in striatal mitochondrial respiration as well as loss of antioxidant enzymes, Cu-Zn superoxide dismutase (SOD), Mn SOD and cytochrome c (cyt c) expression. Striatal mitochondrial dysfunction correlated with dopamine neuron and behavioral deficits in the aged chronic MPD. When the chronic MPD was exercise-trained on a motorized treadmill 5 days/week for 18 weeks, the dopamine neuronal, mitochondrial and behavioral deficits as seen in the sedentary chronic MPD were prevented. Melatonin (5 mg/kg, i.p), a known natural antioxidant and free radical scavenger was injected to the chronic MPD 5 days/week for 18 weeks. Melatonin alone did not alter the striatal neuronal, mitochondrial and motor functions in normal mice. However, melatonin was effective to reverse dopaminergic, mitochondrial and motor impairment as exercise did to the chronic MPD. We conclude that endurance exercise training and melatonin treatment are effective neuroprotective and mitochondrial protective measures in the chronic MPD. Exercise and melatonin treatment may have the potential to slow the progression of PD related neurodegeneration.
Binding and Signaling Differences between Prostaglandin E1 and E2 Mediated by Prostaglandin E Subtype Receptors
(2010-08) Chillar, Annirudha; Ruan, Ke-He; Chow, Diana Shu-Lian; Gao, Xiaolian; Williams, Louis; Das, Joydip
Prostaglandin E1 (PGE1) and E2 (PGE2) are ligands for the prostaglandin E2 receptor (EP) family, which consists of four subtype receptors, designated as EP1, EP2, EP3 and EP4. Interestingly, PGE2 mediates inflammation whereas PGE1 acts as an anti-inflammatory factor. However, the molecular basis of their opposite actions on the same set of EP receptors is poorly understood. To study the ligand recognition differences, a potential high throughput mutagenesis and constrained peptide was used. A peptide constrained to a conformation of the second-extracellular loop of human prostaglandin-E2 (PGE2) receptor subtype 3 (hEP3) was synthesized. The contacts between the peptide residues at S211 and R214, and PGE2 were first identified by NMR spectroscopy. The results were used as a guide for site-directed mutagenesis of the hEP3 protein. The S211L and R214L mutants expressed in HEK293 cells lost binding to [3H]PGE2. This study found that the non-conserved S211 and R214 of the hEP3 are involved in PGE2 recognition. The mutant S211L was able to give a calcium signal with PGE1, but not with PGE2. This implied that the corresponding residues in other subtype receptors could be important in distinguishing the different configurations of PGE2 and PGE1 ligand recognition sites. Direct transfection of point mutants in the EP1 receptor extracellular loop (using PCR products) was evaluated in HEK293 cells. Twenty-four EP1 extracellular loop mutants (alanine scan) were generated using phosporylated primers and ligase. The PCR product was directly transfected into HEK293 cells and the [3H]-PGE2 binding and PGE1 and PGE2 calcium signaling assay evaluated. Three mutants, A104G, P105A and P184A, showed reduced [3H]PGE2 binding, but could not differentiate between PGE1 and PGE2 in the calcium signaling assay. However, we propose that this novel high throughput mutagenesis approach using direct PCR product transfection can be integrated into a high throughput screening machine in the future. The PGE1 and PGE2 binding affinity on the four human recombinant EPs expressed in the live HEK293 as stable cell lines was determined by [3H]PGE2 binding. The PGE1 and PGE2 signaling on the four EPs was determined by the calcium (Ca2+) and cyclic AMP signaling. The Kd for [3H]PGE2 was calculated using saturation kinetic experiments. The IC50 of PGE2 and PGE1 were calculated from [3H]PGE2 displacement experiments using cold PGE2 and PGE1, respectively. PGE2 showed higher affinity or preference for EP3 and EP4 as compared to that of EP1 and EP2. PGE1 also showed a higher Ca2+ signal in EP1 as compared to that of PGE2. There was a two-log concentration difference between PGE2 and PGE1 for generation of Ca2+ signal in EP4. There was no difference in cAMP accumulation with PGE1 and PGE2. Leukotriene C4/D4/E2 levels were higher in the EP1 stable cell line upon stimulation with PGE2, but not PGE1. An anti-inflammatory molecule, 20 hydroxy lipoxin B4, peak was observed using mass spectroscopy with PGE1 and not PGE2. We also used a newly engineered hybrid enzyme (COX-2-10aa-mPGES-1) linking COX-2 and mPGES-1 together thus adopting the full biological activity of COX-2 and mPGES-1 in directly converting AA to PGE2. This enzyme was genetically introduced into HEK293 cells. These cells expressing the COX-2-10aa-mPGES-1 were producing higher level of PGE2 using endogenous AA as confirmed by LC/MS analysis. A new mouse model of cancer was developed by subcutaneous injection of these cells into Balb/c/nu/nu mice. A 100% (8 out 8) occurrence rate of cancer mass was detected in these cells. In contrast, 30% occurrence of cancer mass were determined for the groups of the cells co-expressing the individual COX-2 and mPGES-1. The presence of EP1 and EP2 stable cell line growth around these tumor masses confirmed their involvement in cancer. In conclusion, the Ca2+ signal indicated that the EP1 is likely the dominant and ligand-differentiating receptor in terms of signaling in tissues that co-express the EPs (cancer cells). PGE2 is likely to cause inflammation through leukotrienes and PGE1 is likely to be anti-inflammatory due to its ability to produce Lipoxin B4. High throughput mutagenesis for producing multiple-point mutations using direct PCR product transfection is a promising new method for the future. The experiments on nude mice indicated that the sole coupling of COX-2 to mPGES-1 is a powerful cancer-advancing factor, which implies that the coupling of COX-2 to mPGES-1 is a promising target for anti-cancer drug development. EP1 and EP2 receptors were identified as the likely receptors, to induce cancer. This study provides a molecular basis to understand the biological functions of PGE1 and PGE2 through their binding and signaling properties.
Self-perceived and actual knowledge of Attention-Deficit Hyperactivity/Disorder: A comparison between graduate students in medicine,mental health, and education
(2010-08) Hofer, Stephanie B.; Kubiszyn, Thomas; Schanding, G. Thomas, Jr.; Horn, Catherine L.; Andrews, Nicole L.; Curtis, David F.
Attention-Deficit/Hyperactivity Disorder (ADHD) is a common and increasingly diagnosed disorder among school-age children. Medical professionals, mental health professionals and educators can play an integral role in the identification, assessment and treatment process; therefore, it is helpful to know how much knowledge of ADHD graduate students in these fields possess. The present study assessed self-perceived and actual knowledge of ADHD between graduate students in medicine, mental health, and education. Participants were graduate students in medicine, mental health, and education from the Houston/Galveston area. Participants completed an online survey measuring self-perceived and actual knowledge of ADHD. A bivariate correlation was conducted to determine the relationship between self-perceived and actual knowledge. A Multivariate Analysis of Variance(MANOVA) was used to compare between group differences in self-perceived and actual knowledge. The covariate was years of graduate/professional training. Descriptive statistics were used to assess levels of ADHD training and to identify current and preferred sources of ADHD training. Results from the study showed a significant positive correlation between self-perceived and actual knowledge. Results from the MANOVA showed graduate fields of study were significantly associated with both dependent variables. Further analysis indicated a significant difference in both self-perceived and actual knowledge between graduate students in mental health and in medicine, with the mental health sample having higher levels of knowledge. The sample of graduate students in education did not show any significant differences compared to the other two fields. Graduate students in mental health had the highest levels of self-perceived and actual knowledge, followed by the education sample and then medicine. Graduate students in the three fields generally reported below average to average levels of training regarding ADHD from their graduate programs. Regarding where graduate students prefer to receive ADHD training, all graduate students reported that they prefer to receive more ADHD training from multiple sources including classes, articles, and workshops. Future research may want to further assess the level of training regarding ADHD provided by graduate programs and determine what should be considered an adequate level of knowledge for future practitioners. In addition, outcomes of this study may also support future research on a collaborative consultation model.
Interpreting The Process Of Configuration of Packaged Software Through the Lens of Social Construction of Technology
(2010-08) Mousavidin, Elham; Silva, Leiser; Scamell, Richard W.; Porra, Jaana; Kotarba, Joseph
Despite the predominance of packaged application software, information systems (IS) researchers have focused more on custom software development. Packaged software deserves to be investigated separately due to the uniqueness in terms of its development and implementation. One of the challenges for organizations is to fit packaged software into their organizational context in order to reap the benefits through adopting the best practices this type of software promises to offer. This dissertation concerns the implementation of packaged software, specifically, technical and organizational aspects of its post-purchase configuration. An interpretive study aimed at investigating this process through the lens of Social Construction of Technology (SCOT) was conducted. SCOT is a sociological approach to studying development of technological artifacts. One of the main premises of SCOT is that various relevant groups influence the course of development of a technological artifact based on their varied interpretations of the artifact. SCOT lent itself well to the context of this study, in which the influence of the understanding, perceptions and expectations of various groups on the configuration process of packaged software was studied. The empirical part of this dissertation consists of two case studies: a pilot study at a non-profit organization and a main case study at a large public organization. The pilot study was conducted in 2005 with the aim of examining SCOT in the context of IS research and refining it as a theoretical lens for this dissertation. The data collection for the main case study began in Spring 2007 by contacting a public organization that was in the process of implementing a work management software package. The researcher participated as a neutral observer in the simulation sessions conducted during the configuration of this software. In addition, during the configuration process, the researcher reviewed organizational documents related to the project and conducted semi-structured interviews with the members of the configuration team. The findings of this dissertation exhibited that the configuration of packaged software was an interpretive process through which various features were implemented. The final implementation of each feature was the result of the interpretation and re-interpretation of various configuration options. Each process of interpretation and re-interpretation generally resulted in a dominant interpretation, the output of which took the form of a minimal, moderate, or elaborate configuration solution. For each feature, the choice of one of these solutions was influenced by the discourse forces (optimism, pessimism, and indifference) that were dominant at the time. The generalization of these findings was theoretically modeled in a mechanism for the process of configuring packaged software. In addition, this study suggested a re-conceptualization of what constitutes an IS user. Traditionally, most IS studies have had an individualistic view of users and users are grouped based on their functional roles. The findings of this dissertation proposed treating users as social actors, the grouping of whom is based on their interpretations of the IS with which they interact. Based on such a view, grouping of users occurs after their interpretations and perceptions are sought. This is different than the prevalent approach of first grouping the users (mostly based on their functional roles) and then assigning certain beliefs and perceptions to each group. The findings of this dissertation add to IS theory and practice. A theoretical contribution consists of adding to the literature on software configuration by providing a mechanism as well as a definition of the configuration process. In addition, this research makes a contribution to the SCOT approach in the context of its application in IS research since this theory has not been applied holistically in IS studies. It is believed that practitioners can benefit from the findings of this research by applying the configuration mechanism developed as an analytical tool to understand and manage the process of configuring packaged software.
Understanding the Relationship of Multicultural Case Conceptualization, Multicultural Counseling Self-Efficacy, and Ethnocultural Empathy in Psychology Trainees
(2010-08) Singh, Sharon; Coleman, M. Nicole; Arbona, Consuelo; McPherson, Robert H.; Watson, Margaret
The multicultural competency instruments have been criticized for their ability to accurately assess this construct. Specifically, the lack of adherence to an operationalized definition is at the heart of the problem. In order to improve the theoretical foundation of multicultural competency, this study extended previous research by Ladany and his colleagues (1997) and Constantine and Ladany (2000) by utilizing an objective method to assess psychology trainees’ ability to conceptualize a client of color. Furthermore, this study included additional variables hypothesized in the literature to address some of the deficits found in the existing literature including ethnocultural empathy and multicultural counseling self-efficacy. Participants included 156 masters and doctoral students who were currently enrolled in counseling, counseling psychology or clinical psychology programs throughout the United States. Those who volunteered to participate completed an online case conceptualization task (i.e., objective measure) for a hypothetical Black client that assesses two interrelated cognitive processes: differentiation and integration. Differentiation is defined as a trainees’ capability of providing more than one way of viewing a client’s presenting problems and ways of treating him/her. Integration refers to the level of associations between and among the distinguished interpretations. Two psychology students, 1 undergraduate level and 1 master’s level, blind to the specifics of the study, were trained to code the data. The first conceptualization was rated on the degree of differentiation and integration of ethnic/racial issues/factors(s) contributing the etiology of the client’s difficulties. The second conceptualization was rated on the degree of differentiation and integration of the trainees’ beliefs about what would be an effective treatment plan in handling the client’s problems. This study explored the relationship between psychology trainees’ degree of multicultural case conceptualization with his/her level of self-reported multicultural self-efficacy as assessed by the online version of two recently developed measures, the Multicultural Counseling Self-Efficacy Scale-Racial Diversity Form (MCSE-RD; Sheu & Lent, 2007) and self-reported ethnocultural empathy as measured by the scale of Ethnocultural Empathy (SEE; Wang, Davidson, Yakushko, Savoy, Tan & Bleier, 2003). According to counseling psychology literature, the last two variables may help clarify the underpinnings of multicultural counseling competency. A hierarchical multiple regression equation examined to what extent the trainees’ scores on the MCSE-RD and SEE predicted his/her ability to conceptualize a multicultural client. Previous multicultural training (i.e., multicultural courses and clinical practice with multicultural clients), and year in the program were controlled for since these variables have been found to directly influence trainees’ self-endorsed level of multicultural counseling competency. There were four major findings in the study. First, self-reported multicultural counseling self-efficacy (MCSE-RD) scores were significantly and positively related to a hours of clinical experience, more specifically, hours spent working with racially/ethnically diverse clients and supervision discussing them. However, self-reported ethnocultural empathy (SEE) scores were not associated with any of the training demographic variables. Thirdly, amount and type of multicultural training had no relationship with multicultural case conceptualization in either the etiology or treatment response. Finally, self-reported multicultural counseling self-efficacy (MCSE-RD) scores did not add significant variance when predicting scores of trainees’ demonstrated case conceptualization skills above and beyond his/her level of multicultural training. Therefore, further research is needed to investigate the utility of these assessment tools to clarify what constructs they are measuring of psychology trainees. Implications for research, training and practice are discussed.
Perfectionism, Societal Messages, Gender and Race as Correlates of Male Body Image
(2010-08) Grammas, Debbie; Schwartz, Jonathan P.; Arbona, Consuelo; Wiesner, Margit F.; Olvera, Norma E.
Many men experience psychological distress as they try to obtain the ideal body as constructed by society (Pope, Phillips, and Olivardia, 2000). The number of articles focusing on men and muscularity has greatly increased since the year 2000 (Thompson & Cafri, 2007). Research indicates that body dissatisfaction is increasing in males and even young boys are experiencing body image dissatisfaction (Pope et al., 2000). Men with body image concerns are at risk for low self esteem, eating disorders, use of steroids, anxiety and depression (McCreary & Sasse, 2000; Cafri, Strauss, & Thompson, 2002; Olivardia, Pope, Borowiecki, & Cohane, 2004). Examining the predictors of body image distress is critical. Perfectionism and gender role socialization have been related to a drive for muscularity in men (Davis, Karvinen & McCreary, 2005; McCreary, Saucier, & Courtenary, 2005). In addition, viewing images of muscular men and reading fitness magazines have been linked to body dissatisfaction in men (Lorensen, Grieve, & Thompson, 2004; Morry & Staska, 2001). While the relationships between perfectionism, internalization of ideal standards transmitted by the media, and gender role conflict have been examined with body image dissatisfaction in men, no studies have linked these variables together in a single model. Investigating how these variables interact may lead to a greater understanding of the distress that men experience due to the socialization process of masculinity. The lack of racial diversity has been a limit of several research studies. The purpose of this study was to examine the relation between: 1) perfectionism and male body image dissatisfaction, and 2) internalization of societal messages and male body image, and to determine what role gender role conflict plays, if any in the hypothesized correlation. Data was collected from an ethnically diverse sample of 331 college men from a university in the southwestern United States. Hierarchical multiple linear regression analyses were conducted. Results indicated that identifying as an Asian American, socially prescribed perfectionism, and internalization of societal messages were significant positive predictors of muscle dissatisfaction. Higher levels of socially prescribed perfectionism and internalization of societal messages were related to higher levels of dissatisfaction with the amount of one’s body fat. None of the variables examined served as a predictor for height dissatisfaction. Gender role conflict did not serve as a moderator in the relationship between the variables and male body image dissatisfaction.

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