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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.
1

Quantitative Factors Correlated with Increased Length of Stay for Adult Patients Presenting to the Emergency Department with Abdominal and Pelvic Pain

Spiro, Joshua 19 May 2017 (has links)
A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine. / Abdominal/pelvic pain is one of the most common reasons that patients present to hospital emergency departments (ED). With 129.8 million emergency department visits per year nationally, efficient triage and admission of these patients from the ED is essential. At the New York Methodist Hospital (NYMH) ED, patients presenting with abdominal/pelvic pain are evaluated based on a series of factors such as pain scores, past medical history, physical exam, and laboratory tests. Depending on these factors, clinicians observe, evaluate, and treat their patients requiring varying lengths of stay in the emergency department before either being discharged or admitted to the hospital. Physicians must weigh the benefits and risks of each evaluation they perform knowing that their resources may be needed more urgently by other patients. Determine the quantitative factors correlated with an increased length of stay for adults presenting to the emergency department with abdominal or pelvic pain. Increases in factors such as age, pain, BMI, and vital signs will correlate with an increased length of stay in the emergency department as well as an increased rate of admission to the hospital. Data regarding the above factors were abstracted from a sample of adult patients (n=347) presenting to the New York Methodist hospital emergency department from June 1st, 2013 to May 31st, 2014. The review of patients presenting to the emergency department with abdominal/pelvic pain demonstrated that patients with lengths of stay greater than four hours had a significantly higher value for age, weight, BMI, and blood pressure compared to those with lengths of stay less than four hours. Additionally, patients that were admitted to the hospital had a statistically significantly higher value for age, pain scores, systolic blood pressure, and heart rate. The identification of factors associated with longer lengths of stay provides the first step in identifying how to improve patients’ access to care in a more time efficient manner. Understanding what factors account for delays in care and discharge will allow for more efficient allocation of time and resources to the patients that need it most.
2

A DOUBLE‐BLINDED RANDOMIZED TRIAL OF IV IBUPROFEN AND MORPHINE COMBINATION THERAPY IN PATIENTS PRESENTING TO THE EMERGENCY DEPARTMENT WITH RENAL COLIC

Hintzen, Calliandra 10 April 2015 (has links)
A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine. / Renal stones (or “calculi”) are a relatively common condition, affecting up to 12 percent of people during their lifetime. Typical presentation of renal calculi is acute, intermittent flank pain, termed “renal colic”, which may radiate to the groin. Pain may be accompanied by hematuria, nausea, or vomiting.1 Acute renal colic is a common cause for presentation to the Emergency Department, accounting for an estimated 1 million emergency room visits annually in the United States.2 The severe pain associated with renal calculi requires immediate analgesia, and effective analgesia is associated with improved functional capacity after drug administration.3 In this trial, we compare the efficacy of IV ketorolac vs. IV ibuprofen for pain control in patients with renal colic in a three‐armed double‐blind prospective trial. Patients were randomized to one of three treatment groups, receiving parenteral infusions of either IV ibuprofen + morphine, IV ketorolac + morphine, or morphine monotherapy. Outcome of drug administration was measured by patients’ self‐assessment of pain on a verbal scale at 15 mins, 30 mins, 60 min, and 120 min after drug administration. We hypothesized that IV ibuprofen would provide effective, non‐opioid pain relief in the emergency setting and might have a lower incidence of adverse effects than ketorolac. Need for rescue analgesia (with 4 mg morphine) was observed as an indirect measure of analgesic efficacy. A total of 11 patients completed the study. There was no significant difference in area under the curve of pain score in any of the three treatment arms (p>0.4). The ibuprofen group demonstrated consistent improvement in pain over the course of 120 min of study, with 100% of the patients in that arm demonstrating downtrending pain scores. Though the sample size was too small to identify a statistically significant difference in need for rescue medication, there was a trend toward increased opioid in the ibuprofen group, with 50% of those participants receiving rescue analgesia with morphine. The sample size of this pilot study is inadequate to fully assess the analgesic efficacy of IV ibuprofen for renal colic. A trend toward improved pain control in the ibuprofen group was observed, with 100% of the patients in the ibuprofen arm reporting decreased pain after 120 minutes (as compared to 66% in the ketorolac arm and 75% in the placebo arm). Further study of efficacy and need for rescue analgesia is warranted.
3

THE IDENTIFICATION OF DETECTABLE GRAVITATIONAL WAVE SIGNATURES WITHIN THE EINSTEIN FORMALISM FOR VARIOUS CLASSES OF GALACTIC SOURCES

Maritz, Jacques 27 October 2014 (has links)
A central result of this thesis is the prediction of short period (transient) GW signatures, using General Relativity. This thesis focused on various LIGO and SKA Gravitational Wave (GW) sources such as collapsing supernovae, rapidly spinning magnetars, the coalescence of compact binary objects and the stochastic Gravitational Wave backgrounds produced by Super Massive Black holes. Upper limits for the GW amplitudes and frequencies were predicted by means of numerical and analytic methods. Finally, the prospects of detecting Gravitational Waves from the galactic center will be discussed.
4

IN SITU PREPARATION AND PROPERTIES OF RUBBER/INORGANIC OXIDE NANOCOMPOSITES

Mokhothu, Thabang Hendrica 30 October 2014 (has links)
The present paper is concerned with the preparation of a filled elastomer by means the non-conventional bottom-up approach to polymer composites, alternatively with the conventional mechanical compounding of preformed filler particles with rubber. EPDM rubber was modified with in situ generated silica particles prepared by means of a sol-gel process adopting a solution process. The used synthetic procedure permitted the preparation of highly filled rubbers (up to 40 wt% of silica) with silica particle dimensions ranging from 0.2 to 2 μm. Equilibrium swelling and extraction tests indicated a hindering effect of the presence of in situ generated silica on the vulcanization process which reduced the cross-linking degree of the rubber matrix. Both tensile tests and dynamic-mechanical analysis showed a significant improvement in the mechanical properties due to the presence of the reinforcing filler, with an enhancement more significant than that expected from a simple hydrodynamic reinforcing mechanism.
5

MATERIAL PROPERTIES OF SEMICONDUCTING NANOSTRUCTURES SYNTHESIZED USING THE CHEMICAL BATH DEPOSITION METHOD.

Koao, Lehlohonolo Fortune 06 November 2014 (has links)
The recent global research interest in wide band gap semiconductors has been focused on zinc oxide (ZnO) due to its excellent and unique properties as a semiconductor material. The high electron mobility, high thermal conductivity, good transparency, wide and direct band gap (3.37 eV), large exciton binding energy (60 meV) at room temperature and easiness of growing it in the nanostructure form, has made it suitable for wide range of applications in optoelectronics, piezoelectric devices, transparent and spin electronics, lasing and chemical sensing. PbS nanostructures is a narrow energy gap material which have relevance for optical applications in the near-IR region of the electromagnetic spectrum such as telecommunications, photovoltaics and bioimaging. It has similar electron and hole effective masses hence the exciton, can be strongly confined which is not always feasible in other semiconductors. Thus the PbS system provides an ideal platform to investigate the exciton in the strong confinement regime. In this thesis, structural and luminescence properties of undoped and doped ZnO and PbS nanostructures (nanorods, nanoflakes, nanoparticles, and nanoflowers) are investigated by different approaches for possible future application of these nanostructures as solar cells and light emitting diodes. Undoped and doped ZnO and PbS nanostructures were grown by chemical bath deposition process. Still it is a challenge for the researchers to produce a stable, reproducible high quality and homogeneously doped ZnO/PbS materials and this seriously hinders the progress of ZnO and PbS nanostructcures to be utilized in various applications. The first part of the thesis includes synthesis of undoped ZnO nanostructures by controlling the growth parameters such as concentrations of precursors (zinc acetate) and synthesis time. Crystalline zinc oxide (ZnO) flower-like nanostructures were synthesized by the chemical bath deposition (CBD) method. The X-ray diffraction (XRD) pattern for the ZnO flower-like microstructures showed crystalline peaks corresponding to a hexagonal wurtzite ZnO structures. Scanning electron microscopy (SEM) observations showed the presence of microcrystallites forming microflower-like aggregates. In the case where a higher molar concentration of zinc acetate was used in the preparation process the microflower-like structures were larger in size than that of the lower mol% used. The shape however did not change. The absorption edges red shifted slightly with an increase in the molar concentration of the zinc acetate and in synthesizing time. The band gap energies decreased slightly with an increase in the molar concentration of the zinc acetate and again in synthesizing time. PL showed that the maximum luminescence intensity was reached at the ZnO synthesized for 5 minutes, any further increase in the synthesizing time resulted into the luminescence intensity decrease. An increase in zinc acetate mol% resulted only in a decrease in luminescence intensity. Controlling growth parameters is important in the sense of controlling the physical, electronic, and chemical properties of materials. In order to understand how to tune these properties in the nanostructure, it is necessary to have an understanding of the growth mechanism that dictates the morphology, structure, and rate of growth of the nanomaterial. The ZnO nanostructures (flower-like rods) were later doped with rare-earth elements (e.g. Ce3+ and Eu3+) and transition metal (e.g. Cu2+). Flower-like hexagonal ZnO:Ce3+ nanostructures obtained for undoped and low mol% of Ce3+. ZnO changed into mixed structure with emergence of pyramids for higher mol% Ce3+. The absorption edges showed that as the molar concentration of Ce3+ ions increases the optical absorption edge shift to a higher. The band gap energies decreased linearly with Ce Concentration. The luminescence bands of undoped ZnO nanoflower-like was quenched and shifted from the yellow region to the blue region when ZnO flower-like was doped with different molar concentration of Ce3+. Eu3+ doped ZnO flower-like structures were synthesized. The XRD spectra of the undoped and low concentration Eu3+ doped ZnO nanostructures correspond to the various planes of a single hexagonal ZnO phase. In contrast with Ce3+ doping, the morphology of the ZnO flower-like rods totally changed to large blocks shape when doped with Eu3+ ions. The effective band gap energy of the ZnO decayed exponentially with the addition of Eu3+. The maximum luminescence intensity was also measured for the same sample. Although weak luminescence was observed for excitation above the band gap at 300 nm the best results were obtained by exciting the Eu3+ directly through the 7F0 â 5L6 absorption band at 395 nm. Excitation at a wavelength of 395 nm produced the highest Eu3+ luminescence intensity without any noticeable ZnO defect emissions. In this work undoped and Cu2+-doped ZnO nanostructures were prepared by the chemical bath deposition (CBD) method. XRD analysis showed the sample prepared were hexagonal ZnO for undoped and Cu-doped. The presence of Cu2+ ions caused the particle size of ZnO flower-like structures to decrease. In the UV-Visible study the reflectance intensity decreased with an increase in the molar concentration of Cu2+ and there was no shift in the absorption edges. The luminescence intensity was found to be a maximum for the undoped ZnO flower-like structures and quenched after addition of Cu2+ ions. In the last part of the thesis, the influence of synthesis temperature and molar concentration of lead acetate on the structure, morphology and optical properties of PbS nanoparticles were investigated. The X-ray diffraction (XRD) peaks correspond to the various planes of a single phase cubic PbS. The surface morphology study revealed nanorod structures at low synthesis temperatures but a particulate structure at the high synthesis temperatures. It was also observed that an increase in the molar concentration of lead acetate has no significant influence on the morphology of the PbS nanorods and the crystallite sizes. The reflectance spectra showed a shift of the absorption edge to a higher wavelength with an increase in the synthesis temperature and molar concentration of Pb acetate. The luminescence intensity was found to decrease with an increase in the synthesis temperature and molar concentration of Pb acetates. The PbS nanoparticles were later doped with Tb3+ and co-doped with Ce3+ ions. When the Tb3+ concentration was increased to 2 mol%, the morphology of the PbS:Tb3+ changed to a mixture of spherical nanoparticles and nanorods. The absorption edges of these PbS nanoparticles slightly shifted to higher wavelength depending on the ionic strength of the precursors. The PL result show an increase in emission intensity with an increase in Tb3+ ions up to 0.3 mol% Tb3+ and decreased there after most probably due to luminescence concentration quenching. A new band at 433 nm was found to emerge as the Tb3+ ions increases. Co-doping PbS nanostructures with 0.3 mol% and 2 mol% Ce3+, the spherical nanoparticles changed the morphology to the nanorods surrounded by the spherical nanoparticle. It was also observed that the size of the nanorods increased with an increase in the molar concentration of Ce3+ ions. The nanoparticles showed good optical properties with high reflectance in the UV and visible regions. The absorption edges shifted to higher wavelength with the addition of Tb3+ and Ce3+, respectively. The photoluminescence results displayed an optimum increase in luminescence intensity when the ratio of Ce:Tb was 1:10 and further increase in cerium content quenched the luminous intensity. It was observed that as the molar concentration of co-dopant (Ce3+) increased the luminescence band at around 433 nm diminished.
6

Appraisal of space valuation approaches as criteria of department location within a department store

Hess, Nancy Rose, January 1961 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1961. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 125-127).
7

State control of civil aviation in the British Empire

Leathem, Ronald M. January 1936 (has links)
Only maps no. 1, 2, 5, 6 are included.
8

An Examination of Academic Department Chairs in Canadian Universities

Boyko, Lydia 24 February 2010 (has links)
This thesis is a baseline, population study, designed to create historical and contemporary contexts for and to inform current understanding of the department chair function in Canadian universities. Chairs are explored from five discrete yet dependent perspectives to discern distinctions and associations among institutions, disciplines/fields of study and individuals: What is the job? Who holds the job? Does formal position prescription match practice? Has the job changed over time? What makes department chairs job ready and effective? Canvassing 43 predominantly English-language public universities in 10 provinces, the inquiry encompasses four data sources: (1) 58 university policy documents and faculty association collective agreements; (2) a national electronic survey in two versions – for incumbent chairs, which generated replies from 511 email recipients, representing 38 per cent of the 1,333 individuals in the population approached; and for incumbent deans, sought for their views of the chair function, which drew the participation of 79 email recipients of 269 prospective contributors, signifying a 29 per cent response rate; (3) telephone interviews with 30 chairs and 15 deans (active, former and retired); and (4) curricula vitae of 134 chairs and deans (active, former and retired). The findings confirm the longstanding tradition of the job’s temporary nature, irrespective of institution and discipline. Candidates are usually drawn from tenured faculty ranks, primarily from the immediate unit. The notion of non-academic professionals from outside the university setting occupying the role is viewed by chairs and deans with disdain and is not evident in practice, either in hard pure and applied fields of study such as science, engineering and medicine, or in the soft pure and applied areas such as arts, business and education. The notion of a business-oriented approach to departmental administration appears to be largely a function of an institution’s size and its culture shaped by senior management rather than its location, age and type or a specific discipline with the exception of medicine and engineering. Chairs remain members of the collective bargaining unit in unionized faculty associations during their term of office and typically deem their ability to lead professorial peers with authority constrained as an equal.
9

An Examination of Academic Department Chairs in Canadian Universities

Boyko, Lydia 24 February 2010 (has links)
This thesis is a baseline, population study, designed to create historical and contemporary contexts for and to inform current understanding of the department chair function in Canadian universities. Chairs are explored from five discrete yet dependent perspectives to discern distinctions and associations among institutions, disciplines/fields of study and individuals: What is the job? Who holds the job? Does formal position prescription match practice? Has the job changed over time? What makes department chairs job ready and effective? Canvassing 43 predominantly English-language public universities in 10 provinces, the inquiry encompasses four data sources: (1) 58 university policy documents and faculty association collective agreements; (2) a national electronic survey in two versions – for incumbent chairs, which generated replies from 511 email recipients, representing 38 per cent of the 1,333 individuals in the population approached; and for incumbent deans, sought for their views of the chair function, which drew the participation of 79 email recipients of 269 prospective contributors, signifying a 29 per cent response rate; (3) telephone interviews with 30 chairs and 15 deans (active, former and retired); and (4) curricula vitae of 134 chairs and deans (active, former and retired). The findings confirm the longstanding tradition of the job’s temporary nature, irrespective of institution and discipline. Candidates are usually drawn from tenured faculty ranks, primarily from the immediate unit. The notion of non-academic professionals from outside the university setting occupying the role is viewed by chairs and deans with disdain and is not evident in practice, either in hard pure and applied fields of study such as science, engineering and medicine, or in the soft pure and applied areas such as arts, business and education. The notion of a business-oriented approach to departmental administration appears to be largely a function of an institution’s size and its culture shaped by senior management rather than its location, age and type or a specific discipline with the exception of medicine and engineering. Chairs remain members of the collective bargaining unit in unionized faculty associations during their term of office and typically deem their ability to lead professorial peers with authority constrained as an equal.
10

The illusion of community participation : experience in the irregular settlements of Bogotá

Hataya, Noriko January 2008 (has links)
The study focuses on community participation among the poor of Bogota, Colombia. It explores the changing relationships between poor communities, local politicians and the city government before and after the institutional reforms and changing approach to development that occurred during the 1990s. The case studies were conducted in six irregular settlements, all developed in contravention of the city's planning regulations. Data were collected using a sample household survey and in-depth interviews with community leaders, local inhabitants and the representatives of outside organisations. In the 1990s, clientelistic practices became less effective to push the regularisation process. City programmes toward irregular settlements became more holistic and benefited from better coordination between the different public entities. As a result, the inhabitants became more discriminating in identifying the most effective strategies for obtaining the services and infrastructure that they required. Competent government intervention was ultimately the most important factor in furthering the regularisation process. However, regularisation could not be achieved without community participation. Community involvement was important both before and after a settlement was recognised. The community had to find the money to put down a deposit before the service agencies would install services. This required not only a minimum level of economic resources but also firm community leadership. The study also shows that apparently contradictory decisions made by the different communities were highly rational. Whether the inhabitants were willing to pay for services depended on the benefit they expected in return. Their criteria changed through the consolidation process because their most urgent needs changed. Today, after the pricing system of public services changed, access to services depends mostly on users' purchasing power and not on the collective negotiation led by the JAC leaders. In the 1990s, under the new constitution with its laws protecting citizen's rights, 'participation' of citizens in the political arena as well as their right to obtain basic services was clearly recognised. Under this legal framework, community participation gives the poor a voice with which they can present claims as well as criticise the negligence of public administration. However, the protests of the inhabitants against increased public service charges show that the community-based organisations sometimes still have reason, and the ability, to mobilise the local people as a final resort.

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