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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.
841

Characteristics of Adult Inpatient Traumatic Brain Injuries

Huber, Mark, Skrepnek, Grant January 2011 (has links)
Class of 2011 Abstract / OBJECTIVES: The overall purpose of this study was to describe comorbidities, charges, and mortality associated with inpatient, adult traumatic brain injury (TBI) cases in the United States (US) for the year 2007. METHODS: This was a retrospective cohort analysis of discharge records located in the National Emergency Department Sample (NEDS) of the Healthcare Cost and Utilization Project (HCUP). Descriptive statistics are provided for comorbidities, charges, and mortality. Logistic regression was performed to find characteristics associated with mortality while multiple regression was used to assess charges. Independent variables included age, injury severity, procedures used, location of TBI, and primary payer. RESULTS: A total of 639,698 TBI cases were found which were associated with 267,061 hospital admissions, over $17 billion in hospital charges, and 20,620 deaths in the year 2007.Most common comorbidities were essential hypertension, sprains and strains of the back, tobacco use, fluid and electrolyte disorders, and alcohol-related disorders. Characteristics associated with increased mortality and charges included New Injury Severity Score (NISS) over 10, involvement of a firearm, falls, motor vehicle traffic, and intubation. CONCLUSION: The current study gives the most current picture of inpatient adult TBI cases throughout the US. Future research is warranted to ensure that optimal outcomes are being attained in this vulnerable patient population.
842

The Top 25 Comorbidities Reported During Inpatient Stays for Pediatric Hematopoietic Stem Cell Transplant: Patient Demographics and Impact on Inpatient Mortality and Charges

Zulueta, Stacy, Clemans, Emily, Skrepnek, Grant January 2011 (has links)
Class of 2011 Abstract / OBJECTIVES: The purpose of this study was to analyze the impact of patient and hospital characteristics as well as selected comorbidities on inpatient mortality and charges in pediatric HSCT. We have determined the top 25 comorbidities reported during all inpatient stays for HSCT as well as for those stays ending in mortality. METHODS: All data was extracted from the AHRQ KID databases for the years 1997, 2000, 2003, and 2006. Two regression analyses were performed to determine the contribution of various independent variables on mortality and charges. Subjects of this study included all cases of HSCT reported in the Healthcare Cost and Utilization Project (HCUP) KID as ICD-9 41.XX. RESULTS: Factors accounting for larger increases in cost included death during hospital stay, the development of disseminated intravascular coagulation (DIC), pneumonia, and length of stay (LOS). The largest decreases in charges were seen for patients coming from a small or “micropolitan” location, patients cared for in teaching hospitals, and in hospitals with large bedsizes. Variables associated with increased risk of mortality on linear regression included development of DIC, sepsis, or pneumonia. CONCLUSION: Further study relating to HSCT is necessary to determine the contribution of specific comorbidities to mortality and charges. Importantly, DIC is associated with both greater risk of mortality and greater charges. It would be prudent to recommend increased monitoring and early treatment for DIC based on these results.
843

Kwalitatiewe en kwantitatiewe inname van staandehooi van twee Cenchrus ciliaris kultivars (Afrikaans)

Jacobs, Salmon Stephanus 04 April 2007 (has links)
The aim of the study was to determine if significant differences, in terms of grazing parameters, intake, animal performane and digestibility, existed between foggage of Cenchrus ciliaris cv. Molopo and Cenchrus ciliaris cv. Gayndah. A grazing trial as well as a partial digestibility study was done with sheep. The following parameters were used: grazing parameters (dry matter availability and structure of the grazing), qualitative and quantitative intake, animal production and partial digestiblity. The grazing trial was conducted over two years and further divided into two separate periods of utilisation, middle and late winter. The second trial was a partial digestibility experiment conducted during the second year. In terms of the production parameters of the two varieties: dry material production and sward length of C. ciliaris cv. Molopo was constantly higher than that of C. ciliaris cv. Gayndah. In the grazing experiment the quality of selected material did not differ between C. ciliaris cv. Gayndah and Molopo. Differences in most parameters were not significant. Experimental animals grazing Gayndah selected a diet with higher N- and NDF-concentrations, as opposed to animals grazing Molopo. The same trend continued during the second year but only for N-concentration. In terms of quantitative observations in the grazing experiment the intakes of the two varieties were high for the whole duration of the trial. Only during the "out"-phase of period 1 in 1991, animals on C. ciliaris cv. Molopo couldn’t maintain an intake to meet maintenance requirements. Experimental animals gained weight in the first period of grazing of the first year of the study but not during the rest of the trial. Although intake was high in the other periods, these intakes didn’t support growth or maintenance. This suggests that supplementation in the form of a lick could address possible deficiencies. In the partial digestion trial animals grazing C. ciliaris cv. Gayndah, as opposed to animals on cv. Molopo, selected a better quality material but quantitatively there were no significant differences. For both varieties the amount of organic material consumed wasn’t adequate to meet maintenance requirements. There were no significant differences in the partial digestibility of organic material or nitrogen. Animals on both varieties were in a negative nitrogen balance. / Dissertation (MSc Agric (Animal and Wildlife Sciences))--University of Pretoria, 2007. / Animal and Wildlife Sciences / unrestricted
844

The nature of precipitated gypsum in a soil irrigated with gypsiferous water

Grobler, Lindi 06 October 2005 (has links)
Please read the abstract in the section 00front of this document / Dissertation (MSc (Soil Science))--University of Pretoria, 2005. / Plant Production and Soil Science / unrestricted
845

Anti-inflammatory, anti-oxidant and wound-healing properties of selected South Africa medicinal plants

Mzindle, Nonkululeko Betty January 2017 (has links)
Submitted in fulfillment for the Degree of Master of Applied Sciences in Biotechnology, Durban University of Technology, Durban, South Africa, 2017. / South Africa has a wide range of medicinal plants that are used traditionally by black Zulu South Africans for the treatment of a range of illnesses, including inflammatory ailments; disease conditions caused by oxidative stress and wound healing. It has been indicated that bioactive compounds isolated from plants contribute to their anti-inflammatory, antioxidant and wound healing properties; hence, herbal remedies have been widely used traditionally in many countries in the management and treatment of wounds. Inflammation is the main condition that relates to a variety of diseases affecting most of the world’s population. It is the body’s immune response to infection and injury and is induced by the release of pro-inflammatory mediator’s —prostaglandins and leukotrienes—following wound occurrence. Wounds result in disruption of living tissue caused by oxidative stress. Anti-inflammatory agents, antioxidants, and antimicrobials play an important role in the wound healing process and they prevent aggravated wound conditions.Controlling inflammation during wound repair is important to minimize any additional complications that may result; hence, chemical agents such as non-steroidal anti-inflammatory drugs (NSAIDS), synthetic antioxidantsand steroids are frequently used. These drugs block the enzymes that are responsible for prostaglandin synthesis in inflammation, react with free radicals thereby interfering with oxidation process as a result affect one or more phases of wound healing. The use of these drugs, however, has been limited as they can cause detrimental side effects when used over long periods of time.There is, consequently, a need to find alternative natural therapeutic drugs. Studies on medicinal plants confirmed that herbal drugs exhibit fewer side effects in comparison with chemical agents and are more cost-effective.Thus the aim of this study was to investigate South African medicinal plants, for anti-inflammatory, antioxidant and wound healing properties. Dissolved extracts of thirty-eight medicinal plants were evaluated for theiranti-inflammatory activity using the 5-lipoxygenase assay as well as free radical scavenging activity using the 1; 1-diphenyl-2-picrylhydrazyl (DPPH) assay.Their safety was evaluated using brine shrimp lethality assay. Proliferation and viability of fibroblast cells was determined by the3-(4, 5-dimethylthiazolyl)-2, 5-diphenyltetrazolium bromide(MTT) assay furthermore a scratch wound assay was used to study the properties of wound healing in vitro and to confirm the anti-inflammatory activities of the dissolved extracts. Migration rate was evaluated quantitatively by an image analyzer. Methanol was chosen for extraction because it completely dissolves extracts. Anova was used for statistical analysis. Almost all aqueous extracts were found to be effective in inhibiting lipoxygenase enzyme when compared to nordihydroguaiaretic acid (NDGA). Aqueous extracts exhibited remarkably high percentage inhibition of lipoxygenase with most above 100% when compared to methanolic extracts. Amaranthus dubius and Portulaca oleracea were found to have good biological activities in the inhibition of 5-lipoxygenase enzymes when compared to the other plants. However, Galinsoga parviflora and Syzygium cordatumwere least effective in inhibiting enzyme activity with percentages as low as -2% and 34% respectively. Percentage inhibitions for methanolic extracts were lower than that of aqueous extracts. Amaranthus spinosus had the highest percentage inhibition among all the methanolic extracts andGalinsoga parviflorahad the lowest. The methanolic plant extracts were found to be more effective in scavenging DPPH free radicals than the corresponding aqueous extracts. All the methanolic extracts exhibited free radical scavenging ability in the range of 60%–104%. Asystasia gangetica, Ficus sur, Heteropyxis natalensis, Hibiscus sabdariffa, Pelargonium sp. showed notably higher scavenging abilities, ranging from 101%–104% compared to Rutin. Methanolic extracts of Heteropyxis natalensis and Hibiscus sabdariffa exhibited scavenging ability even at the lowest concentration of 10μg/ml. Furthermore, aqueous extracts displayed remarkably lower activities than methanolic extracts with thirty-one extracts having a scavenging capacity ranging from 22%—59%. None of the extracts were found to be detrimental to brine shrimp. Almost all the extracts were shown to stimulate the growth of fibroblast cells except the methanolic extract of Solanum nodiflorum, which was shown to be killing the cells at high concentrations with a percentage viability of 46%.As the concentration decreased, however, the viability of cells with this extract increased to 143%. An increase in the number of fibroblast cells was observed in the scratched area of the treated cells and a significant migration rate was also noted with some of the extracts. Aqueous extracts of Sonchus oleraceus (86%), Justicia flava (85%) and Dichrostachys cinerea (85%) and methanolic extracts of Senna occidentalis and Hibiscus sabdariffa were found to have the highest migration rate compared to untreated cells that served as a control. No cell migration was observed with methanolic extract of Solanum nodiflorum.Instead, the extract was found to be toxic to the cells. Some of the plants evaluated in this study have been studied for either anti-inflammatory, antioxidantand wound healing properties in vivo, however, no work has been conducted to demonstrate a correlation between anti-inflammatory, antioxidant and wound healing properties of plant species in vitro. The current study was, therefore, conducted to review medicinal herbs considered as anti-inflammatory, antioxidants and wound healing agents as well as collecting evidence for their effectiveness and pharmacological mechanisms in modern science. In the plant species investigated Amaranthus dubius, Asystasia gangetica, Bidens pilosa, Buddleja saligna, Carpobrotus dimidiatus, Chenopodium album, Dichrostachys cinerea, Emex australis, Ficus sur, Guilleminea densa, Hibiscus sabdariffa, Physalis viscose, Syzygium cordatum, Taraxacum officinale and Tulbaghia violacea demonstrated good anti-inflammatory and wound healing properties.In conclusion the results from this study demonstrated promising anti-inflammatory and antioxidantactivities as well as wound healing properties,furthermoreit was aslo shown that the plant extracts were not toxic to the cells hencethis suggested that the plants investigated, can be used as substitutes or to formulate wound healing agents that are safe to use in primary healthcare. / M
846

Design, implementation and evaluation of a directly water cooled photovoltaic- thermal system

Mtunzi, Busiso January 2013 (has links)
This research project was based on the Design, Implementation and Evaluation of a Photovoltaic Water heating system in South Africa, Eastern Cape Province. The purpose of the study was to design and investigate the scientific and economic contribution of direct water cooling on the photovoltaic module. The method involved performance comparison of two photovoltaic modules, one naturally cooled (M1) and the other, direct water cooled module (M2). Module M2 was used to produce warm water and electricity, hence, a hybrid system. The study focused on comparing the modules’ efficiency, power output and their performance. The temperatures attained by water through cooling the module were monitored as well as the electrical energy generated. A data logger and a low cost I/V characteristic system were used for data collection for a full year. The data were then used for performance analysis of the modules. The results of the study revealed that the directly water cooled module could operate at a higher electrical efficiency for 87% of the day and initially produced 3.63% more electrical energy each day. This was found to be true for the first three months after installation. In the remaining months to the end of the year M2 was found to have more losses as compared to M1 as evidenced by the modules’ performance ratios. The directly water cooled module also showed an energy saving efficiency of 61%. A solar utilization of 47.93% was found for M2 while 8.77% was found for M1. Economically, the project was found to be viable and the payback period of the directly cooled module (M2) system was found to be 9.8 years. Energy economics showed that the system was more sensitive to the price changes and to the energy output as compared to other inputs such as operation and maintenance and years of operation. A generation cost of R0.84/kWh from the system was found and when compared to the potential revenue of R1.18 per kWh, the system was found to enable households to make a profit of 40.5 %. Use of such a system was also found to be able to contribute 9.55% towards carbon emission reduction each year. From these results, it was concluded that a directly cooled photovoltaic/thermal heating (PV/T) system is possible and that it can be of much help in terms of warm water and electricity provision.
847

Time budgets, avoidance distance scores-related behaviour and milk yield of pasture-based Jersey, Friesland and cross bred cows

Dodzi, Madodana Sunson January 2010 (has links)
Time budgets, avoidance distance scores-related behaviour and milk yield of pasture-based Jersey, Friesland and crossbred cows. by Madodana Sunson Dodzi The study was conducted at the University of Fort Hare farm to determine the time budgets, the avoidance-related behaviour variables and their relationship with milk yield in three pasturebased dairy genotypes: Jersey, Friesland and crossbreed. Twenty one clinically health dairy cows aged between 52 and 55 months, in mid lactation and comprising of seven cows from each genotype were used in the study. The time spent on different activities (grazing, lying down, standing and others) at pasture was recorded using stop watches across four seasons. The behavioural responses of the three genotypes to humans were determined by recording their avoidance distance scores (AD), exit speed (ES), pen scores (PS), pen behaviour scores (PBS), plat form scores (PLS) and the occurrence of kicking (KCK) and stepping (SPG) during milking on four consecutive days in four seasons. Time spent standing was higher (P < 0.05) for Friesland compared to Jersey and crossbred during the hot-wet season. In the cool-dry season the Jersey spent more time (P < 0.05) grazing than the other breeds. The Friesland and crossbred on the other hand devoted most of their time lying down compared to Jersey in the cool- dry season (P < 0.05). There were season differences in time spent on all activities (P < 0.05). Time spent on grazing was longest in post-rainy seasonal and lowest in hot- wet season (P < 0.05). The longest lying down period was observed in the hot-dry season and lowest in hot-wet season (P < 0.05). iii Daily milk yield Varied (P < 0.05) with genotype with the Friesland and Jersey producing higher yield than the crossbred. The highest amount was produced in hot-dry and the least in hot-wet season. Milk yield was positively correlated (P < 0.05) with lying down. Standing was negatively correlated with milk yield (P < 0.05). The Friesland had the highest avoidance distance scores (P < 0.05) and the Jersey had the lowest avoidance distance scores in all seasons. There was an association (P < 0.05) between genotype and exit speed scores, pen scores and stepping behaviour scores. The Friesland exhibited the highest exit speed scores than the other breeds. The Jersey had the lowest (P < 0.05) kicking behaviour scores. There was a relationship (r = 0.64) between avoidance distance scores and exit speed. Exit speed scores were correlated with pen score(r= 0.23). Milk yield was significant related (r= 0.17) to the occurrence of kicking behaviour. The genotypes showed different levels of sensitivity to season and milk yield was influenced by breed and season. It can be concluded that time budgets vary with season and farmers need to adopt measures that buffer the effect of season on welfare of dairy cows. It can also be concluded that avoidance distance scores differs according to genotype with Jersey being more confident to humans than other two breeds. It is therefore recommended that provision of shades or cooling mechanism should be adopted to buffer the effects of hot-wet season. Improving quality of feed during the cool-dry season may be critical for Jersey cows. Finally positive handling of the dairy cows is recommended in order to improve the welfare and milk yield of pasture based dairy cows.
848

Pharmacotherapies in Parkinson Disease: Investigating Trends and Adverse Health Outcomes

Crispo, James Alexander George January 2016 (has links)
Parkinson disease (PD) is the second most common neurodegenerative disease worldwide, with estimates suggesting that PD prevalence and incidence will increase with aging populations. Therapeutic options and clinical guidelines for PD have significantly changed over the past 15 years; however, pharmacoepidemiology data in PD are lacking, especially regarding adverse effects of non-ergot dopamine agonists (DAs) and outcomes associated with anticholinergic burden. The objectives of this doctoral research are threefold: 1) examine patterns of antiparkinson drug use in relation to clinical guideline publication, drug availability, and emerging safety concerns; 2) determine whether PD patients treated with non-ergot DAs are at increased risk of adverse cardiovascular or cerebrovascular outcomes; and 3) determine whether anticholinergic burden is associated with adverse outcomes in PD. Specific research questions were investigated using epidemiological methods and electronic health data from Cerner Health Facts®, an electronic medical record database that stores time-stamped patient records for more than 300 Cerner subscribing facilities across the United States. Findings from this work are reported in a series of manuscripts, all of which have been published. Key findings include: 1) DA use began declining in 2007, from 34% to 27% in 2012. The decline followed publication of the American Academy of Neurology’s practice parameter refuting levodopa toxicity, pergolide withdrawal, and pramipexole label revisions; 2) heart failure was the only adverse cardiovascular or cerebrovascular outcome that demonstrated a significant association with non-ergot DA use, mainly pramipexole; and 3) anticholinergic burden in PD was associated with the diagnosis of fracture and delirium, and significantly increased the risk of emergency department visit and readmission post inpatient discharge. Reported antiparkinson prescribing trends suggest that safety and best practice information may be communicated effectively in PD. Although findings warrant replication, individuals with PD and independent risk factors for or a history of heart failure may benefit from limited use of pramipexole. Similarly, individuals with PD may benefit from substituting non-PD medications with anticholinergic effects for equally effective non-anticholinergic agents. Additional pharmacovigilance studies are needed to better understand health risks and the impact of population health interventions in PD.
849

Model efektivního využití pracovníků v manažerské praxi / The model of effective use of human resources in practice of management

Bondari-Ardamatskaia, Olga January 2008 (has links)
Creation of a theoretical model rests upon connection of three scientific areas -- management of organization, management of human resources and psychology and sociology of management. Detailed study of these areas lead to creation of different parts of this model. Generally, model can be characterized as a mechanism of accomplishing a state of equilibrium between working activities of organization and its employees (both individuals and working teams).
850

Finanční analýza KUPÁLA, s.r.o. / Financial Analysis of KUPÁLA, Ltd

Rabas, Jan January 2014 (has links)
The aim of this thesis is perform financial analysis of KUPÁLA spol. s r.o. within four-year period from 2010 to 2013. First, the various methods of financial analysis are theoretically described, including value and bankruptcy models and economic value added. Then the described methods are applied to a particular company. Selected resulting values are compared with average values in the sector each year. In conclusion of this thesis is the evaluation of the analysis and draw conclusion about the company's financial situation.

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