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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
631

Predicting Lumbar Fusion Surgery Outcomes From Presurgical Patient Variables: The Utah Lumbar Fusion Outcome Study

DeBerard, M. Scott 01 May 1998 (has links)
Lumbar fusion surgery is a commonly used procedure to treat severe spinal pathology and associated chronic disabling low back and leg pain. Despite the common incidence of spinal fusion surgery, few studies have examined patient outcomes or predictive correlates of this procedure. The objectives of this study were to characterize Utah workers who received lumbar fusion surgery in terms of relevant presurgical and outcome variables and to identify presurgical correlates of patient outcomes. An archival prospective research design was utilized consisting of a retrospective medical chart review and a postsurgical telephone outcome survey. Subjects were 203 workers' compensation patients from the state of Utah who have undergone spinal fusion surgery and who were at least 2 years postsurgery at time of follow-up. Outcomes were assessed for 144 of the 203 patients (71%). Presurgical measures _included demographic, work, compensation, disability, health, surgical, and physiological variables. Outcome measures included solid arthrosis, patient satisfaction, work disability status, functional disability due to back pain, and multidimensional health. Analysis of patient outcome data revealed that solid arthrosis was achieved in 71.9% of patients. Forty-six percent of subjects felt their back/leg pain problems were worse than what they had expected following the surgery, and 42 % felt that their quality of life had not changed or worsened as a result of lumbar fusion. Twenty-eight percent of fusion patients were work disabled at follow-up. Fusion patient mean outcome scores on multidimensional health measures reflected poorer health than comparative medical patient and nonpatient norms. The most consistent presurgical correlates across outcomes were lawyer involvement, number of prior low back operations, age at injury, and household income at time of injury. Results are compared to data from previous lumbar fusion research studies and reasons for varying findings are offered. Implications of the findings are discussed in terms of inadequate patient selection and insufficient assessment of patient outcomes in low back research studies. Limitations of the present research are discussed, including how placebo, natural history, and regression to the mean can lead to erroneous conclusions about the efficacy of lumber fusion surgery. Suggestions for improvements in low back surgery outcome research are offered.
632

Effects of Fluoride Availability Availability on Fluoride Content of Deciduous Teeth of Children and Bone Measurements in Some Utah Communities

Lowgren, Monika Margareta 01 May 1976 (has links)
The relationship between the fluoride content of the enamel and dentine of deciduous teeth and the number of tooth lesions/mouth was compared to fluoride treatment in Logan , Brigham City, Helper and Milford, Utah. Bone measurement data was obtained on the second metacarpal bones of the mother s of the participating children from the same communities except Brigham City. The fluoride treatment in the communities were as follows: Logan has no fluoride added to the domestic water supply but some children received fluoride treatment through tablets, drops, etc. Milford has water which naturally contains 0 . 8 ppm fluoride , Helper and Brigham City have 1 ppm fluoride added to their water ,supplies. The results showed that significantly less (P > 0.05) fluoride existed in the dentine of teeth originating from Logan children without fluoride treatment than the dentine from fluoride treated children in Logan and Brigham City. The fluoride content of the enamel showed a tendency to be increased with increasing amount of fluoride exposure. The fluoride content of the enamel and dentine from non fluoride treated Logan children was considerably less than from fluoride treated Logan children and from Brigham City children. Logan children who had received fluoride treatments had significantly (P > 0.05) fewer dental lesions/mouth compared to the nontreated Logan children. The fluoride exposed Milford and Helper children had a greater frequency of dental lesions/mouth than even nonfluoride treated Logan children . This might be explained by the socioeconomic differences existing between Logan in comparison to Helper and Milford. Midshaft bone measurements were taken on x-rays of the second metacarpal of women (average age 35.7) residing ten or more years in the respective community. When measuring cortical thickness, cortical area, medullary area, and per cent cortical area, no significant differences could be shown.
633

Blue Grouse Ecology and Habitat Requirements in North Central Utah

Weber, David A. 01 May 1972 (has links)
The ecology and habitat requirements of a population of blue grouse were studied during 1970 and 1971 on the Cache National Forest 25 miles south of Logan, Utah. Baseline data concerning numbers of blue grouse, vegetative composition, and insect abundance on the study area were gathered. These data were to be compared to similar measurements made following a herbicidal spraying of the area during 1972. Information concerning the breeding, nesting, brood rearing, and wintering habits of the grouse was also collected. Male blue grouse migrated to the study area in early April to set up territories. These were located on open tree-shrub hillsides. Seven nests were located under sagebrush bushes. About 18 to 20 broods were on the study area during 1971. Young grouse consumed insects primarily during the summer. Males migrated from area by July and females and broods moved off in late August and early September.
634

Patrick Edward Connor and the Military District of Utah: Civil War Military Operations in Utah and Nevada 1862-1865

McCarthy, Max Reynolds 01 May 1975 (has links)
Troops, requested by the federal government for the security during the Civil War of the overland mail, telegraph, and emigrant routes, were provided by California for those portions of the routes which crossed the territories of Utah and Nevada. A force, never exceeding 1, 200 in strength, commanded by Patrick Edward Connor, was assigned a geographic responsibility, the Military District of Utah. Connor's California Volunteers established principal troop locations at Fort Churchill and Fort Ruby in Nevada, and at Camp Douglas and Fort Bridger in Utah Territory during mid-1862. Major actions were conducted against the Indians at the battle of Bear River and by the campaign of Spanish Fork canyon, both in early 1863. Thereafter, a series of treaties achieved peace with various Indian tribes. Connor also utilized his troops in a variety of activities peripheral to his primary military mission. Important examples were a colonization effort at Soda Springs, continued and thorough area reconnaissance, and early efforts to develop the territorial mineral resources. Considerations of Mormon intentions, often believed by Connor to be inimical to Union interests, occupied much of Connor's time. Many writers record a generally unfavorable impression of Connor in Utah. However, it is the view of this author that the missions assigned to the federal troops in the District of Utah during the Civil War were important and were effectively carried out.
635

Utah State University Stilling Basin Pipe Flow to Open Channels

Rasheed, Hameed 01 May 1963 (has links)
Energy dissipation problems are often encountered where pipelines discharge into open channels. Normal pipe flow velocities most often result in super-critical velocities in canals. These high velocities may cause scour, overtopping, and unstable flow in the channel. The principal objective of the study was to find an efficient and economical design of a stilling basin transition from pipe flow to open channels. Pertinent variables were selected and their effects determined by extensive experimentation. An efficient stilling basin was developed utilizing a short dissipator pipe on the wall opposite the inflow pipe. The optimum diameter, length, and differential elevation between center lines was determined.
636

A Course Study in Aviation Education Including a Survey of Utah High Schools

Summers, Lowell P. 01 May 1956 (has links)
The increasing importance of the airplane in present day civilization Throughout the ages, after each development in speed of communications and transportation, man has made noteworthy changes in his way of living. Indications are that the gradual development of the airplane to a safe and rapid means of transportation has had a great effect upon society by pushing back the frontiers of the world both geographically and scientifically. The impact of this speed has influenced almost every home and certainly every school in America.
637

Measuring Nonuse Values for Wilderness Designation in Utah-by Contingent Valuation Method

Johnson, Van R. 01 May 1995 (has links)
Since 1964, when Congress wrote the Wilderness Act, there has been an increasing amount of controversy between opponents and advocates of wilderness. Wilderness areas in Utah are not immune to this controversy. Public policy makers and land managers are in the middle of this debate. They have the responsibility to assess the resource and estimate the benefits and costs associated with creating policy. This thesis focusses on helping policy makers and land managers recognize a benefit currently not being assessed. Nonuse values are values other than in situ use, where individuals have a value for existence of wilderness or a bequesting value for future generations. If these values exist, current policy would underestimate the benefits. The results of this thesis revealed Utah citizens have a value for wilderness designation other than in situ use value, with estimation by contingent valuation.
638

Evaluation of a Side-By-Side Full-Scale Biofiltration Conversion in a Nutrient-Limited Environment

Bassett, Stetson S. 01 May 2018 (has links)
In order to meet increasing water demands and more stringent regulations drinking water treatment plant managers must continually look to new treatment strategies and optimization techniques. One such strategy is to eliminate chlorine residual before filtration, allowing indigenous bacteria already present in the source water to grow on the filter media. These microorganisms help improve effluent water quality by increasing organic and inorganic contaminant removal. The process is known as biological filtration, or biofiltration. The implications of converting a conventional filtration plant (not specifically designed for biofiltration) to a biofiltration plant are still not well understood. Therefore, the purpose of this study was to evaluate water quality and operational trends of a side-by-side full-scale biofiltration conversion at the Quail Creek Water Treatment Plant (QCWTP), located in Hurricane, Utah, and to determine the impact of pre-chlorination elimination on filter performance. Four of twelve filters at the QCWTP were used to test the plant’s ability to operate in biological mode. One acted as a control and ran similar to the other eight filters in the treatment plant. The other three were converted to biofilters by quenching the influent chlorine residual with thiosulfate. The experiment lasted one year, so filter performance could be evaluated in each season. The results from the study indicated that the influent water was low in organic carbon (i.e. food for microorganisms), which resulted in small differences in biological activity between filters. Disinfection by-products (DBPs) (i.e. cancer causing agents created from the combination of chlorine and organic matter) were lower in the biofilters relative to the control. Biological conversion resulted in slightly higher and more variable final effluent turbidity values (though still within EPA drinking water standards and operational goals) compared to the non-biological filters; however, filter run times were unaffected.
639

Thrips species infesting tomatoes and other host plants of these insects in northern Utah

Maddock, Darrell R. 01 May 1946 (has links)
The purpose of this study has been to determine which species of thrips infest tomato plants and fruits in northern Utah, and to find out which other plants occurring in this area also serve as hosts for tomato-infesting thrips. Because of the importance of tomato-infesting thrips to the canning industry, it was decided that more complete knowledge of the species of thrips which are found on tomatoes should be obtained. Because most thrips generally have been difficult to control, it was believed that a general knowledge of the plants on which these thrips occur would enable tomato growers to eliminate many such plants from tomato fields and lands adjacent to them, and that such cultivation would tend to decrease thrips populations on tomato fruits and in tomato fields.
640

Magnitude of Displacement and Styles of Deformation on the Paris and Laketown Thrust Faults, Northern Utah

Kendrick, Richard D. 01 May 1994 (has links)
Surface geology is combined with abundant industry seismic-reflection and drill­-hole data in the central Bear River Range and Bear Lake Plateau to depict the forms and interactions of the Paris-Woodruff-Willard, Laketown-Meade-Home Canyon, and Crawford thrust faults. Displacement on the Paris thrust diminished to the south, and died out in splays where displacement was transferred to the Willard thrust. West of Woodruff, Utah, splays of the Laketown thrust deformed a complex footwall imbricate of the Willard thrust. To the east, a major northeast-striking Crawford thrust splay exhibits a change in slip vectors from east to southeast. Reorientation of these slip vectors is recorded by an imbricate stack of thrusts in the Willard thrust footwall to the west. The sharp bend in the surface trace of the Crawford normal fault southeast of Randolph, Utah, reflects the separation of the south-southeast-trending surface traces of the Crawford thrust and this northeast-trending splay. Cross sections indicate that the Sheep Creek thrust, a major splay off the basal decollement at the base of the Crawford thrust sheet, accommodated displacement during the transition from thrusting on the western thrust system (Paris-Woodruff-Willard, and Laketown-Meade-Home Canyon) to the structurally lower eastern thrust system (Crawford, Absaroka, and younger thrusts). The Sheep Creek thrust trends northeast and folded the Laketown thrust in the central Bear River Range. Shortening in the northeast part of the study area was accommodated by the Home Canyon thrust along a detachment in the Jurassic Twin Creek Limestone. Several splays from this thrust extensively folded the footwall of the Meade thrust and rocks of the Bear Lake Plateau, and thereby formed a series of hanging-wall anticlines that have been extensively drilled for hydrocarbons.

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