Theses and dissertations represent a wealth of scholarly and artistic content created by masters and doctoral students in the degree-seeking process. One of the first American universities to require ETDs for graduation, UNT began accepting theses and dissertations in electronic format in 1999.

	Use of In-Stream Water Quality Measurements and Geospatial Parameters to Predict Consumer Surfactant Toxic Units in the Upper Trinity River Watershed, Texas Date: 2008-05 Creator: Johnson, David Richard Description: Surfactants are used in a wide assortment of "down-the-drain" consumer products, yet they are often discharged in wastewater treatment plant effluent into receiving water, potentially causing environmental harm. The objective of this project was to predict surfactant toxic units and in-stream nutrients in the upper Trinity River watershed. Surface and pore water samples were collected in late summer 2005. General chemistries and surfactant toxic units were calculated. GIS models of anthropogenic and natural factors were collected and analyzed according to subwatersheds. Multiple regression analyses using the Maximum R2 improvement method were performed to predict surfactant toxic units and in-stream nutrients using GIS and in-stream values. Both geospatial and in-stream parameters generated multiple regression models for surfactant surface and pore water toxic units, as well as in-stream nutrients, with high R2 values. Thus, GIS and in-stream parameter modeling have the potential to be reliable and inexpensive method of predicting surfactant toxic units and nutrient loading in the upper Trinity River watershed. > more info
	Use of Phillips's five level training evaluation and ROI framework in the U.S. nonprofit sector. Date: 2007-08 Creator: Brewer, Travis K. Description: This study examined training evaluation practices in U.S. nonprofit sector organizations. It offered a framework for evaluating employee training in the nonprofit sector and suggested solutions to overcome the barriers to evaluation. A mail survey was sent to 879 individuals who were members of, or had expressed an interest in, the American Society for Training and Development. The membership list consisted of individuals who indicated association/nonprofit or interfaith as an area of interest. Data from the survey show that training in the nonprofit sector is evaluated primarily at Level 1 (reaction) and Level 2 (learning). It also shows decreasing use from Level 3 (application) through Level 5 (ROI). Reaction questionnaires are the primary method for collecting Level 1 data. Facilitator assessment and self-assessment were listed as the primary method for evaluating Level 2. A significant mean rank difference was found between Level 2 (learning) and the existence of an evaluation policy. Spearman rho correlation revealed a statistically significant relationship between Level 4 (results) and the reasons training programs are offered. The Kruskal-Wallis H test revealed a statistically significant mean rank difference between "academic preparation" of managers with Level 3 evaluation. The Mann-Whitney U test was used post hoc and revealed that master's degree had a higher mean rank compared to bachelor's degree and doctorate. The Mann-Whitney U test revealed that there were statistically significant mean rank differences on Level 1, Level 2, Level 3, and Level 5 evaluation use with the barriers "little perceived value to the organization," "lack of training or experience using this form of evaluation," and "not required by the organization." Research findings are consistent with previous research conducted in the public sector, business and industry, healthcare, and finance. Nonprofit sector organizations evaluate primarily at Level 1 and Level 2. The existence of a written policy increases the use of Level 2 evaluation. Training evaluation is also an important part of the training process in nonprofit organizations. Selecting programs to evaluate at Level 5 is reserved for courses which are linked to organizational outcomes and have the interest of top management. > more info
	Use of Preventive Screening for Cervical Cancer among Low-income Patients in a Safety-net Healthcare Network Date: 2003-05 Creator: Owusu, Gertrude Adobea Description: This study is a secondary analysis of survey data collected in fall 2000 from patients of a safety-net hospital and its eight community health outreach clinics in Fort Worth, Texas. The study examined three objectives. These include explaining the utilization of Pap smear tests among the sample who were low-income women, by ascertaining the determinants of using these services. Using binary logistic regressions analyses primarily, the study tested 10 hypotheses. The main hypothesis tested the race/ethnicity/immigration status effect on Pap smear screening. The remaining hypotheses examined the effects of other independent/control variables on having a Pap smear. Results from the data provide support for the existence of a race/ethnicity/immigration status effect. Anglos were more likely to have had a Pap smear, followed by African Americans, Hispanic immigrants, and finally, by Hispanic Americans. The persistence of the race/ethnicity/immigration status effect, even when the effects of other independent/control variables are taken into account, may be explained by several factors. These include cultural differences between the different groups studied. The race/ethnicity/immigration status effect on Pap smear screening changed with the introduction of age, usual source of care, check-up for current pregnancy, and having multiple competing needs for food, clothing and housing into the models studied. Other variables, such as marital status, employment status and health insurance coverage had no statistically significant effects on Pap smear screening. The findings of this study are unique, probably due to the hospital-based sample who has regular access to subsidized health insurance from a publicly funded safety-net healthcare network and its healthcare providers. Given the importance of race/ethnicity/immigration status for preventive Pap smear screening, public education efforts to promote appropriate Pap smear tests among vulnerable populations should target specific race/ethnicity/immigration status groups in the U.S. within the cultural context of each group. Furthermore, publicly funded health programs for underserved populations such as the John Peter Smith Connections and Medicaid should be maintained and strengthened. > more info
	Use of Satellite Imagery and GIS to Model Brood-Rearing Habitat for Rio Grande Wild Turkey Populations Occurring in the Western Cross Timbers Region of Texas Date: 2002-08 Creator: Miller, Christopher J. Description: Remote sensing and GIS have become standard tools for evaluating spatial components of wildlife habitats. These techniques were implemented to evaluate Rio Grande wild turkey (Meleagris gallopavo) poult-rearing habitat in the Western Cross Timbers region of Texas. Texas Parks and Wildlife (TPWD) random roving turkey counts for 1987-1989 and 1998-2000 were selected, indicating locations where hens with poults were observed. Satellite imagery from 1988 and 1999 was classified and then processed with Patch Analyst. To add robustness, stream, road and census population densities were also evaluated for each turkey location. Analysis of the 1988 canopy cover image, comparing observed locations with randomly-selected habitat cells (N = 20) indicated significant differences (p <.05) for patch edge variables. Mean patch edge was significantly greater for habitat locations where hens with poults were observed than for those selected at random. Spatial data for 1999 did not indicate a significant difference (p < .05) between sampling groups (observed vs. random, N = 30). Significant differences (p <.05) did occur for turkey locations observed in both 1988 and 1999 (N = 7). This demonstrates the adaptability of wild turkey hens, as habitats change over time, hens continued to visit the same locations even though the habitat had significantly changed for select spatial variables. > more info | Use restricted to UNT community
	Use of geographic information systems and infrared-triggered cameras to assess white-tailed deer (Odocoileus virginianus) habitat in Denton County, Texas. Date: 2002-08 Creator: Sallee, David R. Description: This study utilized geographic information systems, remote sensing, and infrared-triggered cameras to assess white-tailed deer habitat in Denton County, Texas. Denton County is experiencing tremendous growth in both population and development. Despite their presence here historically, white-tailed deer were all but extirpated by the beginning of the 20th century, and there are no data available which support their presence in Denton County again until the 1980's. This study attempts to equate the increase in white-tailed deer population to Denton County's transformation from an agricultural to an urban economy and lifestyle. Eighteen sites were chosen throughout the county to research the following metrics: geology, soils, landcover, landscape ecology, streams, shorelines, land use, population, roads, structures, and census methods. > more info
	Use of geographic information systems for assessing ground water pollution potential by pesticides in central Thailand Date: 2002-08 Creator: Thapinta, Anat Description: This study employed geographic information systems (GIS) technology to evaluate the vulnerability of groundwater to pesticide pollution. The study area included three provinces (namely, Kanchana Buri, Ratcha Buri, and Suphan Buri) located in the western part of central Thailand. Factors used for this purpose were soil texture, percent slope, primary land use, well depth, and monthly variance of rainfall. These factors were reclassified to a common scale showing potential to cause groundwater contamination by pesticides. This scale ranged from 5 to 1 which means high to low pollution potential. Also, each factor was assigned a weight indicating its influence on the movement of pesticides to groundwater. Well depth, the most important factor in this study, had the highest weight of 0.60 while each of the remaining factors had an equal weight of 0.10. These factors were superimposed by a method called “arithmetic overlay” to yield a composite vulnerability map of the study area. Maps showing relative vulnerability of groundwater to contamination by pesticides were produced. Each of them represented the degree of susceptibility of groundwater to be polluted by the following pesticides: 2,4-D, atrazine, carbofuran, dicofol, endosulfan, dieldrin & aldrin, endrin, heptachlor & heptachlor epoxide, total BHC, and total DDT. These maps were compared to groundwater quality data derived from actual observations. However, only the vulnerability maps of atrazine, endosulfan, total BHC, and heptachlor & heptachlor epoxide showed the best approximation to actual data. It was found that about 7 to 8%, 83 to 88% and 4.9 to 8.7% of the study area were highly, moderately, and lowly susceptible to pesticide pollution in groundwater, respectively. In this study a vulnerability model was developed, which is expressed as follow: V = 0.60CW + 0.10CS + 0.10CR + 0.10CL + 0.10CSL. Its function is to calculate a vulnerability score for a certain area. The factor “V” in the model represents the vulnerability score of a certain area, whereas CW, CS, CR, CL, and CSL represent the values or classes assigned to well depth, soil texture, monthly variance of rainfall, primary land use, and percent slope in that area. > more info
	Use of luminescence energy transfer probes to detect genetic variants. Date: 2004-08 Creator: Vaccaro, Carlos Description: The purpose of this research was to study the hybridization of molecular beacons under different conditions and designs. Data collected suggest that the inconsistency found in the emission intensity of several of these probes may be caused by 3 important factors: length of the probe, nucleotide sequence and, the formation of an alternative complex structure such as a dimer. Of all three factors, dimer formation is the most troublesome, since it reduces the emission of the reporter molecules. A new probe design was used to reduce dimer formation. The emission signal of the improved probe was several folds stronger than those probes with the early design. In this research, dimer formation is detected, furthermore a new probe with a different design was tested. If dimer formation can be reduced molecular beacons can be integrated into more complex hybridization systems providing an important tool in research and diagnosis of genetic disorders. > more info
	Use of repeated tests and rolling breath averages affects the precision of quantifying the VO2 response profile in moderate intensity cycling. Date: 2006-08 Creator: Pedini, Daniela Marie Description: The purpose of this study was to determine whether working in the field of deaf education, as opposed to general education, results in a higher level of technology integration. A secondary goal was to determine if deaf educators who are deaf integrate technology at a higher level than their hearing counterparts. The instrument chosen for this study was the LoTi Technology Use Profile, a tool used to explore the role of technology in the classroom. A total of 92 participates were included in the study of which 48 were regular educators and 44 were deaf educators. The participants were selected from a population pool whereby teachers were presumably pre-disposed to using technology based upon their attendance at a technology training session in the form of a conference or a class. Deaf educators as a whole did not perform as well as general educators on the LoTi scales. Given the fact that the technology-minded general educators who comprised the sample population of this study scored exceptionally high on the LoTi scales, further research is needed to ensure comparability between the two groups. The findings of the current study do suggest, though, that deaf educators who are deaf have the potential to integrate technology to a greater degree than deaf educators who are hearing. Thus, a primary recommendation is to conduct a national LoTi survey of typical, rather than technology-minded, deaf educators as a comparison to the 2004 national survey of typical general educators. > more info
	Use of the Beck Depression Inventory in Northern Brazil Date: 2002-05 Creator: Albert, Christopher Description: The Beck Depression Inventory (BDI) is a popular screening and research instrument for measuring severity of depression. The instrument was translated to Portuguese for use in Brazil in 1979; however, it was not until recently that its psychometric properties have been tested empirically for the Brazilian population. The purpose of the present study was to explore the BDI's psychometric properties in a northern region of Brazil and to test for possible relationships between certain demographic variables and BDI outcomes. Samples used in this study were from an urban area in Roraima, the northernmost state of Brazil. The BDI showed adequate levels of internal consistency in nonclinical and clinical samples. Female respondents had significantly higher scores than male respondents. Those who had lower levels of education, income, or occupational status had significantly higher scores than those with higher levels of these variables. Adolescents had significantly higher scores than adults from all age groups except those from age 19 to 22. No significant difference was found between those who identified themselves as “indigenous” and those who identified themselves as “non-indigenous.” Regression analysis results showed that the combination of gender, education, and age best accounted for the variance in BDI scores. An ANCOVA revealed that clinically depressed adults had significantly higher BDI scores than nonclinically depressed adults. Factor analysis results showed that there were two main factors in the item structure for both female respondents and male and female respondents combined: one factor of mainly cognitive-affective items and the other factor of mainly somatic items. The results were discussed in terms of the future use of the BDI in Brazil. > more info | Use restricted to UNT community
	Use of the college student inventory to predict at-risk student success and persistence at a metropolitan university Date: 1999-12 Creator: Harris, Joneel J. Description: Using Tinto's longitudinal model of institutional departure as the theoretical basis for this research, the purpose was to determine what extent selected motivational factors measured by the College Student Inventory (CSI) predict academic success and persistence of at_risk students at the University of North Texas (UNT). The study focused on United States citizens and permanent residents entering UNT as at_risk first_time freshmen admitted via individual approval for the fall 1994 semester. The 409 subjects were enrolled in a developmental course titled Personal and Academic Effectiveness where the CSI was administered during the first 2 weeks of class. Selected predictor variables were tested in relation to the separate criterion variables of grade point average and enrolled status during the 2nd and 4th years of the study. Grade point averages and enrollment data for the 1995-96 and 1997-98 academic years were extracted from the student information management system. The research design employed appropriate multiple regressions, multiple correlations, multiple discriminant analyses, and bivariate correlations. Findings confirmed the ability of five CSI factors to predict grade point average (p < .05) of at_risk students over the time frames used in this study. Nine factors predicting enrolled status were also significant at the .05 level; however, results were not meaningful in the 2nd year as factors classified 95% of all subjects as persisters. By the end of the 4th year, the factors were able to predict correct classification of both persisters and nonpersisters approximately 24% better than chance. This research provides support for Tinto's institutional departure model, particularly associated with pre_entry attributes and goals/commitments over time. The CSI is a viable instrument for use with at_risk first_time freshmen at a metropolitan university; however, required enrollment in a developmental course likely confounded the ability of selected variables to meaningfully predict enrolled status during the 2nd year. > more info