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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.
201

EVALUATION OF PROTEIN QUALITY USING MICE VS. RATS

Cossack, Zafrallah Taha January 1980 (has links)
Experiments were designed to investigate the possibility of using mice as model animals for the evaluation of protein quality, and to compare it with rats under the same conditions. Parameters measured were protein efficiency ratio, net protein ratio, protein digestion and relative protein value. Six sources of protein were tested at three dietary levels for each. Measurements were taken at four different periods of feeding, thus, the effects of dietary level of protein and the length of the feeding period were studied. Results on mouse experiment indicated that the highest PER values were obtained at 6 and 8% levels of dietary protein with significantly lower values when 11% levels were fed. The highest NPR values were obtained at 6% level of dietary protein then declined when 8 or 11% levels were fed. The highest efficiency regarding PER and NPR were obtained when mice were fed for 10 days than when they were fed for 14, 21, or 28 days of experiment. High quality protein sources were needed at lower levels in the diet for shorter periods of time to obtain the maximum efficiency when compared to poor quality sources of protein. Results for protein digestion did not correlate with those of PER, NPR or RPV indicating that protein digestion is a poor measurement. However, PER, NPR, and RPV were highly correlated. Results of rat experiment were in agreement with what was reported in the numerous works for rat bioassay in the literature review. Rate of body weight gain increased with increasing levels of dietary protein and the PER reached a maximum value, then decreased. Values of NPR tended to fall with increasing levels of dietary protein. PER values tended to increase gradually with prolonged period of feeding, then decline. The maximum PER values were obtained when 10% level of dietary protein was fed for a period of 15 days. Likewise mice experiment, PER, NPR, and RPV correlated highly while protein digestion correlated poorly with the other methods used. In general mice appeared to be influenced by the same factors as rats when used for the evaluation of protein quality. Mouse could be used as a model animal for protein quality evaluation with the advantages of small animal size, lower feed intake, shorter period of feeding, plus is highly desirable for experiments involving the use of isotopes or whole carcass analysis. A dietary protein level of 8% for a feeding period of 10 days would be suitable for use with mice instead of a 10% dietary level for a 28 day feeding experiment in rats. Whole eggs could be used as a suitable reference standard protein for mouse bioassay.
202

The effect of retrospective utilization review on patient length of stay Annapolis Hospital, Wayne, Michigan : submitted ... in partial fulfillment ... Master of Hospital Administration /

Monge, Peter W. January 1975 (has links)
Thesis (M.H.A.)--University of Michigan, 1975.
203

The effect of retrospective utilization review on patient length of stay Annapolis Hospital, Wayne, Michigan : submitted ... in partial fulfillment ... Master of Hospital Administration /

Monge, Peter W. January 1975 (has links)
Thesis (M.H.A.)--University of Michigan, 1975.
204

A study of refill non-compliance and predictors of refill non-compliance to tricyclic and SSRI antidepressants in a population setting /

Powell, Tammy Lynette, January 1997 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, Faculty of Medicine, 1997. / Typescript. Bibliography: leaves 154-161.
205

Maternal interaction style, reported experiences of care, and pediatric health care utilization

Shellhorn, Wendy Lauran Struchen. January 2006 (has links)
Dissertation (Ph.D.)--University of South Florida, 2006. / Title from PDF of title page. Document formatted into pages; contains 338 pages. Includes vita. Includes bibliographical references.
206

Utilisation of fly ash and brine in a geopolymeric material

Swanepoel, Johanna Cecilia 09 February 2006 (has links)
An increasing demand for electricity in modem society has resulted in the burning of large quantities of coal and ultimately the production of large quantities of fly ash. The petrochemical industry, if based on coal in a country such as South Africa, also produce large quantities of fly ash. In a semi-arid country like South Africa, there is a need to recover water. Processes currently in use for the recovery of wastewater produce large quantities of brines. These brines are stored in waste dams, which are not only expensive to maintain, but also pose a potential threat to the environment. The process of geosynthesis led to the development of a new type of material, namely geopolymers. Geopolymers can best be viewed as a polymeric silicon-oxygen¬aluminium framework with alternating silicon and aluminium tetrahedra joined together in three directions by sharing all the oxygen atoms. Cations such as Na+, K+, Ca2+ and H3O+ must be present in the framework cavities to balance the negative charge generated by the Al3+ in IV-fold co-ordination. It was attempted in this study to manufacture a geopolymeric binder, supplying most of the ingredients through waste materials. In the first set of experiments, matrices containing different amounts of fly ash, kaolinite, sodium hydroxide, sodium silicate and brine or water were synthesised by mixing and heating at 50°C for 24 hours. Compressive strength measurements showed a maximum strength of 4.05 MPa after 28 days. Leaching tests indicated that sodium was the best stabilised showing a stabilisation of between 30 and 40% (70 to 60% of the sodium initially added leached out again). The anions were stabilised to a lesser extent. Infrared spectra obtained confirmed an aluminosilicate structure. The second set of experiments was done to obtain the optimum curing conditions. Matrices containing the same amounts of fly ash, kaolinite, sodium hydroxide, sodium silicate and brine or water were cured at different temperatures and for different time periods. The matrices containing water showed a maximum compressive strength of 7.25 MPa after 28 days when cured at 60°C for 48 hours, while their brine-containing counterparts showed a maximum compressive strength of 7.76 MPa after 28 days when cured at 70°C for 72 hours. Infrared spectra obtained confirmed an aluminosilicate structure while X-ray diffraction patterns obtained indicated a largely amorphous product. In the third set of experiments matrices containing different amounts of fly ash, metakaolinite, sodium hydroxide, sodium silicate and brine or water were synthesised by mixing and heating at the optimum conditions determined previously. Compressive strength measurements indicated a maximum strength of 1.45 MPa after 28 days. Leaching tests indicated a higher stabilisation of the cations than in the first set of experiments. Potassium was the best stabilised, showing a stabilisation of above 80%. The anions were again stabilised to a lesser extent. Infrared spectra obtained confirmed an aluminosilicate structure while X-ray diffraction patterns obtained indicated a largely amorphous material. / Dissertation (MSc (Chemistry))--University of Pretoria, 2007. / Chemistry / unrestricted
207

The impact of surgical day care on hospital inpatient utilization in a paediatric population

Elo, Jyrki A. I. January 1987 (has links)
Day care surgical services have been marketed as a cost saving alternative for inpatient care. There is evidence that the cost per episode of day care surgery is 50-70 percent less than a comparable episode in an inpatient ward. In addition, avoiding hospitalization has particular relevance for paediatrics, because of the undesirable effects of hospital stay on children. However, both cost savings and the quality-based need to decrease hospitalizations of children will be fullfilled only if each patient cared for in a day care surgery unit would otherwise have been an inpatient and the bed vacated by day care surgery use would not be filled in by other patients. In a previous B.C. study based on the total population a significant component of day care surgery was found to augment total utilization, suggesting generation of surgical activity rather than substitution. The present study was designed to examine the substitution/generation issue in the paediatric (0-14 years) population, both because experts questioned the generalizability of the findings to the paediatric population, and because of the dramatic reduction in paediatric utilization in Canada during the period since the mid-1960s. The contention was that the introduction of day care surgery may have been an important factor in this downtrend. The relationship between paediatric day care surgery use and hospital inpatient utilization was analyzed in B.C. in each of the years 1968-1976 and 1981/82-1982/83 and using a time series/cross-section study design. The data frame consisted of all B.C. school districts, in each of the study years, yielding 825 data points. Using a multivariate regression analysis, it was possible to estimate what hospital utilization patterns would have been in the absence of day care surgery capacity, and hence isolate estimates of the net impact of day care surgery on paediatric inpatient use. Findings on the relationship between day care surgery use and paediatric medical/surgical and surgical inpatient utilization strongly support the view that paediatric day care surgery has been largely an add-on to the total hospital care system. Statistically significant substitution effect was revealed only for the most narrowly defined inpatient surgery category which more closely resembled day care surgery-type cases, after controlling for potential confounding effects of age and sex, paediatric bed capacity, different socioeconomic characteristics and time- and district-specific factors. Even here, less than 10 percent of day care surgery represented substitution for inpatient surgery and over 90 percent appeared to be generation of new activity to the hospital system as a whole. Furthermore, paediatric beds which were "saved" by day care surgery use were filled with increased utilization by non-day care surgery eligible surgical patients and by medical cases. The main driving force behind hospital utilization in the 0-14 year age group was paediatric bed availability even after standardization for age, sex, physician stock, measures of socioeconomic status, and other district- and year-specific effects. According to this study paediatric day care surgery has not been a cost saving alternative for inpatient care in B.C. in 1968-1982/83. Neither has it reduced overall hospitalizations in the paediatric population. / Medicine, Faculty of / Population and Public Health (SPPH), School of / Graduate
208

Utilizing CO2 from biomethane production : Sustainability and climate performance

Cordova, Stephanie S. January 2023 (has links)
Biogas solutions offer many benefits for the environment and society, including organic waste treatment as well as being an enabler for energy and nutrient recovery. The products of anaerobic digestion are a biogas, which contains a share of 30 to 50% carbon dioxide (CO2) and 50 to 70% methane, and a liquid remanent, rich in nutrients. The biogas can be upgraded by removing the CO2 to increase the energy content, producing biomethane. At present, CO2 is considered a waste in biomethane production systems, and hence it is emitted into the atmosphere. Nevertheless, biogas upgrading technologies separate a pure-grade CO2 and, likewise, carbon capture processes, providing a pure CO2 flow that can be stored or utilized. Compared to storage, carbon capture and utilization (CCU) technologies deliver valuable carbon-based products required to sustain human activities. The valorization of green CO2 could aid the transition towards defossilization of the economy. Indeed, several CO2 utilization technologies could be incorporated into biomethane production systems, but there is still a limited understanding of the available alternatives and their potential impacts on biomethane systems. This thesis aims to investigate the integration of CO2 utilization technologies in biomethane production systems by revealing its potential, identifying alternatives, and assessing the impacts of the integration. Using Sweden as an example, scenarios of future biomethane production were employed to estimate the potential CO2 available for utilization. To complement the analysis, a qualitative approach made possible the identification of aspects that could affect CO2 utilization in biomethane production. Moreover, a multi-criteria analysis (MCA) framework was developed to identify relevant indicators for assessment and available alternatives for CO2 utilization. The research also includes a life cycle assessment (LCA) to evaluate the climate performance of relevant CCU alternatives in the biomethane production system. Results show that 160 kt of CO2 could be obtained from biomethane production in Sweden, which could potentially increase threefold from 2020 to 2030. The evaluation of alternatives for CO2 utilization includes environmental, technical, economic, and social criteria with sound indicators within an MCA framework. Indicators to evaluate each criterion provide valuable information to identify feasible and sustainable alternatives that can be integrated into biomethane plants. The identified alternatives with a high readiness level are additional methane through methanation, horticulture, mineral carbonates, fuels, pH control, bulk chemicals, and liquefied CO2 for direct use. The results provide information to decision-makers in relation to considerations to take before implementation, like energy requirements, the existence of regulations and standards, and uncertainty. In terms of the climate performance of biomethane with the inclusion of CCU alternatives, the results show a possible reduction of CO2 emissions that depends on the possibility of substituting fossil-based products. The investigated alternatives all result in lower emissions, but concrete curing and methanation using renewable hydrogen produce the best results. To conclude, the potential future increase of green CO2 from biomethane in Sweden creates opportunities to substitute fossil carbon in current applications and mature conversion pathways. Moreover, the inclusion of CCU in biomethane production contributes to reducing biomethane system emissions and diversifying its products. Possible alternatives of CCU that can be integrated into biomethane production systems in the short term include methanation and concrete curing. Other alternatives could be possible but present lower performance and higher uncertainties at the moment. / Biogaslösningar kan ge en mängd positiva miljömässiga och samhällsviktiga effekter, inklusive behandling av organiskt avfall och framställning av energi och näringsämnen. Produkterna från anaerob rötning är dels biogas, som består från 30 till 50% av koldioxid (CO2) och 50 till 70% av metan, dels en flytande rötrest med högt näringsinnehåll. Biogasen kan uppgraderas genom att ta bort CO2 för att öka energiinnehållet, och på så vis framställs biometan. CO2 ses för närvarande som en restprodukt i produktionssystemet och släpps därför vanligtvis ut i atmosfären. Tekniker för uppgradering av biogas liknar dock processer för infångning av CO2, där högkoncentrerade flöden av CO2 lagras (CCS) eller används (CCU). Till skillnad från lagring bidrar tekniken för CCU till att skapa produkter som behövs för att upprätthålla samhällsviktiga funktioner. Dessa valoriseringar av grön CO2 skulle kunna stödja övergången mot ett fossilfritt ekonomiskt system. Faktum är att det finns ett flertal tekniker som skulle kunna integreras i produktionssystem för biometan, men kunskapen om dessa tekniker och deras inverkan på biometansystemet är begränsad. Denna avhandling syftar till att undersöka integrationen av tekniska lösningar för nyttiggörande av CO2 vid framställning av biometan genom att påvisa dess potential, identifiera alternativa tekniska lösningar, och utvärdera integrationens följder. Med Sverige som exempel skapades scenarier för framtida biometanproduktion för att uppskatta mängden CO2 som skulle kunna tas om hand. Som ett komplement till dessa uppskattningar tillämpades ett kvalitativt tillvägagångssätt som identifierade aspekter som skulle kunna påverka CO2-användningen vid biometanproduktion. Dessutom utvecklades ett multikriterieanalytiskt (MCA) ramverk för att identifiera relevanta indikatorer för utvärdering och möjliga alternativ för CO2-användning. En livscykelanalys (LCA) tillämpades även för att utvärdera klimatprestandan för relevanta CCU-alternativ inom produktionssystem för biometan. Forskningsresultaten visar att 160 kt skulle kunna erhållas från biometanproduktion i Sverige. För Sveriges del finns det en potential att öka den insamlade mängden CO2 från biometan upp till tre gånger under perioden 2020 till 2030. I utvärderingen av de tekniska lösningarna inkluderas miljömässiga, tekniska, ekonomiska och regulatoriska kriterier för indikatorer inom ett MCA-ramverk. Dessa indikatorer användes för att utvärdera hur respektive kriterium bidrar till att identifiera realiserbara tekniska lösningar som kan integreras i biometananläggningar. De identifierade teknikerna med hög mognadsgrad är framställning av ytterligare metan genom metanisering, biomassa, karbonatmineral, bränslen, pH-värdesreglering, baskemikalier och flytande CO2 för direkt användning. Varje alternativ har dock faktorer som skulle kunna hindra implementering, såsom höga energikrav, lagstiftningar och standarder samt hög osäkerhet. När det gäller klimatprestandan för biometan med olika CCU-alternativ visar resultaten på en möjlig minskning av CO2-utsläpp som beror på möjligheten att substituera fossilbaserade produkter. Alla de undersökta alternativen resulterar i lägre utsläpp, men härdning av betong och metanisering med förnybar vätgas ger bäst resultat. Slutsatsen som dras är att det finns en stor potential i Sverige att framställa grön CO2 från biometan vilken skulle skapa flera möjligheter att byta fossilbaserade produkter i nuvarande tillämpningar. Införandet av CCU i biometanproduktion kan dessutom bidra till att minska biogassystemets utsläpp och diversifiera produktutbudet. Möjliga alternativ för CCU som kan integreras med biometanproduktionssystem på kort sikt inkluderar metanisering och betonghärdning. Andra alternativ kan också vara aktuella, men uppvisar för närvarande lägre prestanda och högre osäkerhet. / <p>Funding agency: The Kamprad Family Foundation</p>
209

Duplicated Laboratory Tests : A Hospital Audit And Evaluation Of A Computerized Alert Intervention

Bridges, Sharon 01 January 2011 (has links)
Laboratory testing is necessary when it contributes to the overall clinical management of the patient. Redundant testing, however, is often unnecessary and expensive and contributes to overall reductions in healthcare system efficiency. The purpose of this study is two-fold. First, to evaluate the frequency of ordering duplicate laboratory tests in hospitalized patients and the costs associated with this practice. Second, it was designed to determine if the use of a computerized alert or prompt will reduce the total number of unnecessarily duplicated Acute Hepatitis Profile (AHP) laboratory tests. This two-phase study took place in an inpatient facility that was part of a large tertiary care hospital system in Florida. A retrospective descriptive design was used during Phase 1 was to evaluate six laboratory tests and the frequency of ordering duplicate laboratory tests in hospitalized patients and to determine the associated costs of this practice for a 12-month time period in 2010. A test was considered a duplicate or an unnecessarily repeated test if it followed a previous test of the same type during the patient’s length of stay in the hospital and one in which any change in their values likely would not be clinically significant. A quasi-experimental pre- and post-test design was used during phase 2 was to determine the proportion of duplication of the AHP test before and after the implementation of a computerized alert intervention implemented as part of a system quality improvement process on January 5th, 2011. Data were compared for two 3-month time periods, pre- and post-alert implementation. The AHP test was considered redundant if it followed a previous test of the same type within 15 days of the initial test being final and present in the medical record. In phase 1, including each of the six tests examined, there were a total amount of 53, 351 test ordered, with 10, 375 (19.4%) of these cancelled. Out of the total amount of result final tests iv (n = 42,976), including each of the six tests examined, 4.6-8.7% were redundant. Results of the proportion of duplication of the six selected tests are as follows: AHP 196/2514 (7.8%), Antinuclear Antibody (ANA) 120/2594 (4.6%), B12/Folate level 396/5874 (6.7%), Thyroid Stimulating Hormone (TSH) 1893/21595 (8.7%), Ferritin 384/5171 (7.4%), and Iron/Total iron binding capacity (TIBC) 316/5155 (6.1%). The overall associated yearly cost of redundant testing of these six selected tests was an estimated $419, 218. The largest proportion of redundant tests was the Thyroid Stimulating Hormone level, costing a yearly estimated $300, 987. In Phase 2, prior to introduction of the alert, 674 AHP tests were performed. Of these, 53 (7.9%) were redundant. During the intervention period, 692 AHP tests were performed, of these 18 (2.6%) were redundant. The implementation of the computerized alert was shown to significantly reduce the proportion of AHP tests (Chi-Square: χ2 = df 1, p ≤ 0.001). The differences in the associated costs of duplicated AHP were $5238 dollars in 2010 as compared to $1746 in 2011 post-alert and these differences were significant (Mann Whitney U, Z = -4.04, p ≤ 0.001). Although the proportions of unnecessarily repeated diagnostic tests that were observed during Phase 1 of this study were small, the associated costs could adversely affect hospital revenue and overall healthcare efficiency. The implementation of the AHP computerized alert demonstrated a drop in the proportion of redundant AHP tests and subsequent associated cost savings. It is necessary to perform further research to evaluate computerized alerts on other tests with evidence-based test-specific time intervals, and to determine if such reductions postimplementation of AHP alerts are sustained over time.
210

EMERGENCY DEPARTMENT FREQUENT USERS: A LATENT CLASS ANALYSIS AND ECONOMIC EVALUATION TO POTENTIALLY GUIDE UTILIZATION MANAGEMENT INTERVENTIONS

Birmingham, Lauren E. 21 July 2017 (has links)
No description available.

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