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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.
61

"Avaliação da procalcitonina como marcador de sepse e de choque séptico em pacientes pediátricos" / Evaluation of procalcitonin and C reactive protein as a sepsis marker in pediatric patients

Ronaldo Arkader 09 February 2004 (has links)
Sepse bacteriana é a maior causa de morbimortalidade na faixa etária pediátrica e neonatal. A detecção precoce do quadro séptico é difícil, devido os sinais iniciais da doença serem inespecíficos. A possibilidade da existência de exame laboratorial capaz de identificar precocemente quadros sépticos melhoraria o prognóstico desses pacientes. Várias proteínas de fase aguda foram estudadas como marcadores de infecção sendo a proteína C reativa (PCR) a mais utilizada. A procalcitonina (PCT), um pró-hormônio, encontra-se elevado precocemente em quadros sépticos em crianças e adultos. Estudo prospectivo com 14 crianças submetidas à cirurgia cardíaca com circulação extra-corpórea (CEC), com dosagens seriadas de procalcitonina e proteína C reativa, serviram como modelo de resposta inflamatória sistêmica sem infecção com dosagens antes da CEC, após a CEC no primeiro, segundo e terceiro dia após cirurgia, enquanto 14 crianças com sepse/choque séptico dosagens seriadas de PCT e PCR foram obtidas sequencialmente antes do tratamento antibioticoterápico e a cada dia até o terceiro dia. Em crianças sépticas a PCT demonstrou ser superior a PCR como marcador de sepse assim como para diferenciar quadros inflamatórios sistêmicos. / Bacterial sepsis is a major cause of morbidity and mortality in neonates and children. Early detection of bacterial sepsis is difficult because the first signs of this disease may be minimal or nonspecific. The availability of a laboratory test to accurately and rapidly identify septic neonates and children would be of great value in improving the outcome of these patients. Several acute-phase proteins have been used for the diagnosis of bacterial sepsis and C reactive protein (CRP) is the usual marker. It has been reported that the concentration of procalcitonin (PCT), a pro-hormone, is markedly higher in children and adults with sepsis. In a prospective study, 14 children were enrolled after cardiac surgery with cardiopulmonary bypass (CPB), these group represent the non infected children with inflammatory response. Blood samples were obtained before CPB, after CPB, on the first, second and third day after surgery. Another group with 14 children with sepsis or septic shock were enrolled, and blood samples were obtained before antibiotic start, on the first, second and third days. In septic children PCT concentration is a better diagnostic marker of sepsis and to differentiate inflammatory response than CRP.
62

Evaluating Alternative Hydraulic Solutions to Limit Nutrient Contamination of an Aquifer in Southern California

Perry, Jake Mendoza 01 April 2012 (has links)
Many small communities depend on groundwater sources for drinking water and they often use septic tanks for their sewer system needs. However, nitrates and other pollutants from septic systems can percolate to the aquifers and deteriorate quality of the groundwater, threatening the public health. This study has developed a groundwater model using Visual MODFLOW for an aquifer that is used as a water supply source for the cities of Beaumont and Cherry Valley, California. Septic systems are the suspected major source of nitrate contamination of the aquifer. The model has been developed to clarify the extent of interactions between nitrate pollutants, infiltration and percolation from a recently established series of artificial recharge ponds, groundwater recharge from natural sources, and pumping activities to meet local water uses. The primary objective of this study is to evaluate alternative hydraulic solutions that would limit the movement of the contaminants and minimize the risk of affecting the pumping wells. The study attempts to identify the best way to recharge the aquifer and influence movement of the nitrates so that polluted waters may have lower nitrate concentrations in the future, rather than allowed to encroach on critical production wells or led away from production wells to become a problem for future generations or neighboring areas. The data needed to build the model, including geological logs, precipitation, evapotranspiration, well locations, pumping schedules, water levels, and nitrate concentrations have been obtained from the Beaumont Cherry Valley Water District. The model has been calibrated to simulate the observed groundwater levels and the extent of pollution corresponding to the historical pumping rates, recharge rates and climate. The calibrated model has been used to evaluate alternative hydraulic solutions that would either localize the nitrate pollution thus limiting the impact on public welfare, or remove the nitrate pollution for potential treatment and remediation on the surface. The study results show that increased pumping of production wells or strategic placement of additional artificial recharge may reduce the concentrations of nitrate in the Beaumont Basin.
63

Disseminating the Sepsis Bundle: Evaluating an Evidence-Based Education Module

Isopo, Elyse Diana 01 January 2018 (has links)
Due to increasing incidence and noncompliance with sepsis at a local hospital, an educational deficit was identified on the sepsis bundle in the medical intensive care unit. The purpose of this project was to develop and validate a sepsis bundle education program for all frontline staff in the MICU at a local University Hospital. The goal was for the educational tool to be validated by a multidisciplinary team to increase awareness, education, and ultimately, compliance with the severe sepsis and septic shock guidelines. The diffusion of innovation theory was utilized to support the process of change by encouraging the use of screening tools and best practice guidelines. The research question asked whether the education program meets critical care expert panel standards to educate frontline MICU staff on the sepsis bundle. The research design included a 5-member panel of experts in critical care, utilizing the Likert scale to review the proposed educational project on the sepsis bundle. Results are averaged from each reviewer. Results from the review included a unanimous '5' rating on every issue identified, equating to strongly agree on the Likert scale. This rating supported the validity of the educational project, the use of evidence-based practice and that the educational material was clear and easy to follow. Utilizing this validated tool will guide the education of sepsis, severe sepsis, and septic shock and promote social change by increasing education, awareness, recognition and early deployment of the sepsis bundle to improve patient outcomes.
64

Implementing a Sepsis Protocol in a Long-term Care Hospital

Harral, Kristine Lynette 01 January 2019 (has links)
Sepsis is life-threatening organ dysfunction caused by a response to infection that causes multiorgan failure. This condition causes high mortality and morbidity rates and leaves permanent disabilities. The purpose of this project was to create a sepsis protocol and an education training program for clinical staff in a hospital setting where no sepsis protocol was in place. The practice-focused question examined whether an educational program would improve clinical staff perception of their knowledge of the early recognition and management of sepsis. A literature review was conducted to identify an evidence-based practice protocol; the results were used to develop the education program for the clinical staff at the site. Malcolm Knowles'€™s theory of adult learning framed the project that included a team of 9 content experts consisting of physicians, physician assistants, and an educator who reviewed and approved the protocol and education program prior to implementation. The education program was then presented to 45 staff members including physicians, licensed vocational nurses, registered nurses, physician assistants, and nurse practitioners. Results of a 14-item knowledge test before and after the education program were examined for percent correct; results were compared using a paired-samples t test. Participant knowledge increased significantly (p <.05) from 20% correctly answering 10 of the 14 questions on the pretest to 87% answering all of the posttest questions correctly. The results of this project may promote positive social change by supporting clinical staff in early recognition and treatment of sepsis thereby reducing the morbidity and mortality that accompanies sepsis.
65

Cardiac dysfunction and lactic acidosis during hyperdynamic and hypovolemic shock / David James Cooper.

Cooper, David James 1956- Unknown Date (has links)
Bibliography: p. 137-154. / 154 p. : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis details a series of studies in patients, in human volunteers and in large animals. Haemodynamics and left ventricular systolic and diastolic mechanics are reported during lactic acidosis, during therapies for lactic acidosis, and during hyperdynamic and hypovolemic shock. The study has the unifying hypothesis that cardiac dysfunction is important in hyperdynamic and hypovolemic shock and is not caused by lactic acidosis. / Thesis (M.D.)--University of Adelaide, Dept. of Anaesthesia and Intensive Care, 1997?
66

Quantitative microbial risk assessment: a catchment management tool to delineate buffer distances for on-site sewage treatment and disposal systems in Sydney??s drinking water catchments

Charles, Katrina, Civil & Environmental Engineering, Faculty of Engineering, UNSW January 2009 (has links)
On-site sewage systems, such as septic tank-absorption trenches, are used by approximately 20 000 people who live within the catchments that supply Sydney??s drinking water. These systems discharge sewage, treated to varying degrees depending on the system type and level of maintenance, to the environment. This can result in contamination of drinking water supplies if systems are not designed or managed appropriately. The aim of the project was to develop a methodology to define appropriate buffer distances between on-site sewage systems and waterways in Sydney??s drinking water catchments, to ensure the protection of drinking water quality. Specific objectives included: identifying the current status of on-site sewage management; assessing the effluent quality and treatment performance of septic tanks, aerated wastewater treatment systems (AWTS) with disinfection and an amended material sand mound; and development of an appropriate methodology for delineating buffer distances and assessing development applications. Viruses were used as a focus for delineating the buffer distances due to their mobility and robustness in the environment, and the potential health consequences of their presence in drinking water. A Quantitative Microbial Risk Assessment (QMRA) model was developed to calculate the cumulative impact of the on-site sewage systems in the Warragamba catchment based on data from literature and experiments, with consideration of virus loads from sewage treatment plants within the catchments. The model enabled consideration of what was a tolerable impact in terms of the resulting infections within the community. The QMRA the tolerable loads of viruses from the Warragamba catchment were 108 viruses per year in raw water and 104 viruses per year in treated water. A log reduction method was developed to facilitate individual site development assessments. This method was compared to other management approaches to development assessment: fixed minimum buffer distances of 100m, reducing failure rates to zero, and the use of a preferred system. Each of these methods had a limit for how much they could reduce virus loads to the catchment due to either failure or short buffer distances at some sites. While the log reduction method is limited by the failure rates, the method provides a quantitative measure of risk by which maintenance inspections can be prioritised.
67

Electronic noise in nanostructures: limitations and sensing applications

Kim, Jong Un 25 April 2007 (has links)
Nanostructures are nanometer scale structures (characteristic length less than 100 nm) such as nanowires, ultra-small junctions, etc. Since nanostructures are less stable, their characteristic volume is much smaller compared to defect sizes and their characteristic length is close to acoustical phonon wavelength. Moreover, because nanostructures include significantly fewer charge carriers than microscale structures, electronic noise in nanostructures is enhanced compared to microscale structures. Additionally, in microprocessors, due to the small gate capacitance and reduced noise margin (due to reduced supply voltage to keep the electrical field at a reasonable level), the electronic noise results in bit errors. On the other hand, the enhanced noise is useful for advanced sensing applications which are called fluctuation-enhanced sensing. In this dissertation, we first survey our earlier results about the limitation of noise posed on specific nano processors. Here, single electron logic is considered for voltage controlled logic with thermal excitations and generic shot noise is considered for current-controlled logic. Secondly, we discuss our recent results on the electronic noise in nanoscale sensors for SEnsing of Phage-Triggered Ion Cascade (SEPTIC, for instant bacterial detection) and for silicon nanowires for viral sensing. In the sensing of the phage-triggered ion cascade sensor, bacteriophage-infected bacteria release potassium ions and move randomly at the same time; therefore, electronic noise (i.e., stochastic signals) are generated. As an advanced model, the electrophoretic effect in the SEPTIC sensor is discussed. In the viral sensor, since the combination of the analyte and a specific receptor located at the surface of the silicon nanowire occurs randomly in space and time, a stochastic signal is obtained. A mathematical model for a pH silicon nanowire nanosensor is developed and the size quantization effect in the nanosensor is also discussed. The calculation results are in excellent agreement with the experimental results in the literature.
68

Comparative Baseflow Hydrochemistry of Various Septic System Density Groups within the Yellow River Watershed, Gwinnett County, Georgia

Neurath, Robert Carl 03 August 2007 (has links)
Baseflow water chemistry between different septic system density groups was analyzed to understand how septic system usage impacts the water quality of the Yellow River Watershed located in Gwinnett County, Georgia. Seventy water samples were collected at baseflow conditions in the summer of 2006. The samples were analyzed for the abundance and distribution of chlorides, sulfates, nitrates, and specific conductance. Geographic Information Systems were used to determine sample collection sites, assign samples into density groups, and spatially analyze and display the results. Statistical methods were used to compare the results of each density group with all others,and to find any correlation of the anions with respect to specific conductance. Regression coefficient values between nitrate and specific conductance in all groups average 0.77 and the elevated nitrate concentrations in group four suggest a limited relationship between septic system density and baseflow water quality.
69

The Effects of High Density Septic Systems on Surface Water Quality in Gwinnett County, Georgia

Anderson, John R, II 15 December 2010 (has links)
Gwinnett County, Georgia experienced rapid growth in the 1970’s without the infrastructure so septic systems were installed for residential homes. The number of septic systems grew to over 85,000 with a density of 487 septic systems per square mile. This study mapped the distribution of septic systems to determine regions of potential pathogen surface water. This study addressed what potential health risks do high density septic systems have on surface water quality and how can the history of Gwinnett County assist in future development in the Metropolitan Atlanta area? It was found that the density of septic systems has reduced the surface water quality for streams in the Yellow and Alcovy River basins. An average rainfall cause septic flushing and an increase in the fecal coliform. Other trends observed in the surface water quality of increased BOD, water temperature, and various metals also indicated this flushing effect.
70

The effects of septic tank effluent discharge on groundwater quality at Oxford, North Canterbury

Hughes, Brydon Nicholas January 1993 (has links)
The impact of septic tank effluent disposal on groundwater quality was investigated at Oxford. The Oxford township can be regarded as typical of many small communities on the Canterbury Plains which have a high density of septic systems serviced by soakage pit drainage. The primary concern with grouped septic systems is the potential for both chemical and microbial groundwater contamination. The alluvial gravel aquifers of the Canterbury Plains are especially susceptible to microbial contamination due to the high rates of groundwater flow which may transport both bacteria and viral contaminants over large distances. Geological investigations established the presence of an areally extensive, tuff derived, clay unit which forms an aquitard beneath the unconfined aquifer in the north of the Oxford area. Recharge of the unconfined aquifer above the clay unit is exclusively from rainfall infiltration while to the south, groundwater levels respond to rainfall infiltration and influent seepage from the Eyre River. The presence of two hydrogeologically distinct gravel units within the unconfined aquifer was determined by application of the column dilution technique. Point dilution tests showed the average groundwater velocity of 130 m/day in the upper gravel unit to be significantly higher than the 40 m/day measured in the underlying gravels. The presence of discrete channels of preferred flow within the unconfined aquifer system was also established by point dilution tests, intrachannel velocities ranging from 210 to 400 m/day. A resistivity salt tracing test indicated groundwater flow in an easterly direction with a velocity of 250 m/day through an observed channel feature. Groundwater quality monitoring showed a significant degree of groundwater contamination close to the Oxford township. Concentrations of faecal coliform bacteria in excess of drinking water standards were detected up to 900 m downgradient of the nearest septic tank. Elevated levels of chemical indicators (N03-N, CL-) were also detected in all monitoring wells. The pattern of groundwater contamination was complex, reflecting both the heterogeneity of groundwater flow through the unconfined aquifer system and the influence of monitoring well location. Predictive modelling indicated the potential for the transport of faecal coliform bacteria up to 2.6 km downgradient of Oxford. Modelling also suggested increased urban development within Oxford to have a relatively minor effect on the overall extent of groundwater contamination. Additional hydrogeological and water quality data, aided by the application of numerical solute transport modelling techniques, may provide a more accurate estimate of the impact of septic tank effluent disposal on groundwater quality. Future sewage disposal options for Oxford have to balance the low potential for microbial contamination of drinking water supplies outside the groundwater zone delineated by this study, against the environmental acceptability continuing contamination of this zone. This study has identified the need for further research into the effects of septic tank effluent discharge on groundwater quality in the Canterbury region, to provide a sound base for future resource management decisions.

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