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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.
141

Removal of Pharmaceutical Carbamazepine Using Pulsed Corona Discharge Generated in Water

Pourzarea, Roya 11 1900 (has links)
Increasing concentrations of pharmaceutical compounds and their metabolites in aquatic environment threatens both aquatic species and human health. Many pharmaceuticals are persistent in the environment and resistant to conventional water treatment; hence, alternate treatment techniques are required to remove these compounds from water. Aqueous phase electrical discharge has been demonstrated to successfully remove a range of pharmaceutical compounds from water. This technique is characterized by the simultaneous generation of highly reactive species and physical effects within the aqueous solution to be treated. The present study investigates and optimizes the efficacy of pulsed corona discharges generated in water for the treatment of carbamazepine (CBZ) in a relatively clean water matrix by varying the solution pH, solution conductivity, gas type injected, and gas flow rate injected. A point-to-plane reactor configuration was employed to produce plasma channel- streamers. In this geometry, the electrical discharges were produced directly within the aqueous phase to be treated by charging a 1nF pulse forming capacitor using a high voltage (25 KV) DC power supply through 10 MΩ resistor to generate discharges within the water at a 30 HZ pulse repetition rate. Solution pH, solution conductivity, gas type, and gas flow rate were optimized to maximize the removal efficacy of CBZ removal by pulsed corona at the laboratory scale. The CBZ degradation rate (concentration decrease over time) was monitored using LC/MS/MS, with overall degradation ranging from 14-94% depending on the experimental conditions. The results demonstrate that higher CBZ removal efficiency is achieved under lower pH and conductivity conditions. Moreover, enhanced degradation efficiency is obtained when gas, and particularly oxygen, is bubbled through the high voltage hollow electrode, especially at higher flow rates. / Thesis / Master of Applied Science (MASc) / Pharmaceuticals are being released into the environment at an increasing rate due to population growth and a rising dependence on these compounds. Pharmaceuticals are resistant to many common water treatment methods; however, electrical discharge generated within the water to be treated (pulsed corona discharge) is an emerging water treatment technology that has been shown to successfully treat many pharmaceuticals. In the present work, pulsed corona discharge has been used to treat carbamazepine present in a relatively clean water matrix. Removal was maximized by optimizing the solution pH, solution conductivity, type of gas bubbled through the electrode, and gas flow rate. The best removal was achieved in solutions with lower pH and conductivities where oxygen was bubbled through the electrode at a relatively high rate.
142

The Relationship Between Neuronal Discharge and Slow Potentials in the Cat Cerebral Cortex / Neuronal Discharge and Slow Potentials

Langsam, Henryk 11 1900 (has links)
This thesis is missing page 18, the other copies of the thesis are missing it as well. - Digitization Centre / The work reported in this thesis concerns a possible quantitative relationship between two bioelectric phenomena of the cat cerebral cortex: neuronal discharge and slow potentials. A review of literature dealing with research related to the present topic is given. This is followed by descriptions of the experimental procedure employed and the results obtained. A subsequent discussion in terms of current neurophysiological concepts relates present findings with those of other known research. The accompanying bibliography represents a fairly complete coverage of contemporary and recent experimental and theoretical work related to the present topic. / Thesis / Master of Arts (MA)
143

Two-dimensional, Hydrodynamic Modeling of Electrothermal Plasma Discharges

Esmond, Micah Jeshurun 06 July 2016 (has links)
A two-dimensional, time-dependent model and code have been developed to model electrothermal (ET) plasma discharges. ET plasma discharges are capillary discharges that draw tens of kA of electric current. The current heats the plasma, and the plasma radiates energy to the capillary walls. The capillary walls ablate by melting and vaporizing and by sublimation. The newly developed model and code is called the Three-fluid, 2D Electrothermal Plasma Flow Simulator (THOR). THOR simulates the electron, ion, and neutral species as separate fluids coupled through interaction terms. The two-dimensional modeling capabilities made available in this new code represent a tool for the exploration and analysis of the physics involved in ET plasma discharges that has never before been available. Previous simulation models of ET plasma discharges have relied primarily on a 1D description of the plasma. These models have often had to include a tunable correction factor to account for the vapor shield layer - a layer of cold ablated vapor separating the plasma core from the ablating surface and limiting the radiation heat flux to the capillary wall. Some studies have incorporated a 2D description of the plasma boundary layer and shown that the effects of a vapor shield layer can be modeled using this 2D description. However, these 2D modeling abilities have not been extended to the simulation of pulsed ET plasma discharges. The development of a fully-2D and time-dependent simulation model of an entire ET plasma source has enabled the investigation of the 2D development of the vapor shield layer and direct comparison with experiments. In addition, this model has provided novel insight into the inherently 2D nature of the internal flow characteristics involved within the plasma channel in an ET plasma discharge. The model is also able to capture the effects of inter-species interactions. This work focuses on the development of the THOR model. The model has been implemented using C++ and takes advantage of modern supercomputing resources. The THOR model couples the 2D hydrodynamics and the interactions of the plasma species through joule heating, ionization, recombination, and elastic collisions. The analysis of simulation results focuses on emergent internal flow characteristics, direct simulation of the vapor shield layer, and the investigation of source geometry effects on simulated plasma parameters. The effect of elastic collisions between electrons and heavy species are shown to affect internal flow characteristics and cause the development of back-flow inside the ET plasma source. The development of the vapor shield layer has been captured using the diffusion approximation for radiation heat transfer within the ET plasma source with simulated results matching experimental measurements. The relationship between source radius and peak current density inside ET plasma discharges has also been explored, and the transition away from the ablation-controlled operation of ET plasma discharges has been observed. / Ph. D.
144

Consumptive Water Use: Refining State Water Supply Estimates with Discharge and Withdrawal Data

McCarthy, Mary Morgan 11 June 2019 (has links)
Water scarcity has quickly become one of the most pressing issues in the 21st century. Knowledge of the stress consumption places on water supply is therefore necessary for improved resource management. This research leverages monthly facility level withdrawal and discharge data from two different sources to provide important observations of consumptive water use across several spatial scales and water use sectors in Virginia between 2010-2016. Consumptive water is defined as water which is withdrawn and not returned to a water resource system. Consumption was estimated on statewide, watershed, county, and facility levels. The agriculture/irrigation, aquaculture, commercial, industrial, energy, and municipal sectors were considered for analysis. Facilities were matched between the two data sources by narrowing potential matches by distance and then by facility name using an approximate string distance mechanism. This analysis revealed that inconsistent discharge reporting affects estimates of consumption through time and any errors at finer spatial scales are ultimately masked at coarser levels. Statewide energy consumption in Virginia was found to be between 4-20% considering all available data and 0.4-4% across matched facilities. Non-energy consumption was an estimated 37-51% considering all available data and only 28-33% across matched facilities. Inconsistent reporting of discharge made it difficult to determine if consumption trends truly exist in Virginia, but monthly consumption appears to be persistent through time and slightly increasing in non-energy sectors. Industrial consumption in Virginia was also found to be higher than literature values. Results from this study are beneficial for water supply modeling and planning by providing more refined estimates of the actual stress withdrawals place on water supply. / This material is based upon work supported by the U.S. Geological Survey under Cooperative Agreement No. G17AC00322. The views and conclusions contained in this document are those of the author and should not be interpreted as representing the opinions or policies of the U.S. Geological Survey. Mention of trade names or commercial products does not constitute their endorsement by the U.S. Geological Survey. / Master of Science / Water scarcity has quickly become one of the most pressing issues in the 21st century. Improved water resource management is critical for sustainable development, especially in historically water-rich states that have not had an urgency to improve water planning. This research provides key information about the impact consumption has on water supply in Virginia, using water use data from two different sources between 2010-2016. Consumptive water is defined as water which is withdrawn and not returned to a water resource system. This includes losses through evaporation, transpiration, conveyance, and incorporation into products and animals. Consumption was estimated on statewide, watershed, county, and facility levels. It was also estimated for the agriculture/irrigation, aquaculture, commercial, industrial, energy, and municipal sectors. Facilities were matched across the two data sources by narrowing potential matches by distance and then by facility name. This study revealed that statewide energy consumption in Virginia is between 4-20% considering all available data and 0.4-4% across matched facilities. Non-energy consumption is then between 37- 51% considering all available data and only 28-33% across matched facilities. Inconsistent reporting of return flow data made it difficult to determine if consumption trends truly exist in Virginia, but consumption appears to be persistent through time and slightly increasing in non-energy sectors. Results also suggest that industrial consumption in Virginia may be higher than published literature values. This study ultimately introduces a feasible method for water managers to estimate consumption using data from multiple sources. Results from this approach are beneficial for predicting future water demand and long-term resource planning by providing more knowledge of the actual stress withdrawals place on water supply.
145

Evidence of Hydro-Seismicity in the Tennessee Seismic Zone

King, Gregory Lester 17 November 2023 (has links)
Reservoir level and discharge data were collected for three Tennessee Valley Authority (TVA) dams (Chickamauga, Watts Bar and Douglas) on the Tennessee river in the Eastern Tennessee Seismic Zone (ETSZ). Earthquake catalog data was also collected for the ETSZ from 1980-2018. Well levels from 2 U.S. Geological Survey groundwater monitoring wells were also collected. Rainfall data were collected for the ETSZ. Reservoir, well and rainfall data were examined for correlation with earthquake occurrence rates. High Pearson correlation and anti-correlation coefficients (.7-.9) were obtained for the reservoir level and dam discharge volume rates vs monthly earthquake counts. Pearson correlation coefficients for rainfall and well level vs. monthly earthquake counts were small (.0-.2). A large difference in earthquake rates between the months of February (low rate) and April (high rate) over the 39 year study period was observed. The difference in earthquakes rates for February and April are statistically significant at the 95% confidence interval using the two sample Poisson rate test. The high correlations for the reservoir level and flow discharge vs. earthquake counts provides strong evidence of hydro-seismicity occurring in the ETSZ from seasonal fluctuations in reservoir level and discharge flow. / Master of Science / Reservoir level and discharge data were collected for three Tennessee Valley Authority (TVA) dams (Chickamauga, Watts Bar and Douglas) on the Tennessee river in the Eastern Tennessee Seismic Zone (ETSZ). Reservoir discharge and level data was collected for the three reservoirs. Also collected were rainfall data for the study area. This was provided by the TVA. Earthquake and well level data was collected from the USGS. High Pearson correlations for dam discharge and reservoir level vs. earthquake counts provided strong evidence of hydro-seismicity in the ETSZ.
146

Readmission and the social construction of mental disturbance

Terre Blanche, M. J. (Martin J.) 11 1900 (has links)
This dissertation examines recurrent patterns in the interaction between psychiatric patients and the systems of knowledge and power that constitute them as patients. These patterns are traced both in the historical migmti::m of patients into and out of the asylum, and in the language used by doctors and patients to account for such migration. Transcripts of interviews with patients and case notes written by doctors are subjected to new forms of quantitative analysis and this is used together with qualitative interpretation to reveal the ways in which disciplinary power operates through confession and surveillance to constitute psychiatric subjects in the tension between freedom and incarceration. / Psychology / D.Litt. et Phil. (Psychology)
147

"Det känns kul när man kan förbättra saker för patienterna" : En fallstudie av ett förbättringsarbete som syftar till trygg utskrivning från sjukhus

Ericsson, Carin January 2016 (has links)
För patienterna är det viktigt att övergången mellan olika vårdgivare sker på ett tryggt och säkert sätt som underlättar den fortsatta vården. Forskning visar att patienternas delaktighet i förberedelser inför utskrivning från sjukhus ofta brister. Sjuksköterskorna på vårdavdelningen upplevde att arbetet inför utskrivning var stressigt.   Syftet med förbättringsarbetet var att identifiera och implementera åtgärder som möjliggör en välfungerande och trygg utskrivningsprocess. Syftet med studien av förbättringsarbetet var att identifiera faktorer av betydelse för implementeringen av förbättringsåtgärder på en vårdavdelning.Metoden för genomförande av förbättringsarbetet följde principerna för förbättringsrampen. Studien av förbättringsarbetet var en fallstudie med explorativ ansats. Data om personalens erfarenheter av förbättringsarbetet inhämtades med intervjuer som analyserades med kvalitativ innehållsanalys.   Resultatet av förbättringsarbetet visade inte någon mätbar förbättring av utskrivningsprocessen. Resultatet av studien visade att vårdpersonalen ändå upplevde förbättringar och att motivation och praktiska förutsättningar för att delta var viktiga för resultatet.   Slutsatsen var att förbättringsarbetet var värdefullt och medförde ett lärande, även om mätbara mål inte uppnåddes. Ledningsens engagemang var viktigt för att skapa möjligheter för personalen att delta i förbättringsarbete. Valet av förbättringsområde hade stor betydelse för resultatet då det påverkade de medverkandes motivation. / "It feels great when you can improve things for the patients" Safe hospital discharge, a case study of an improvement work   An important aspect of health care, from the patient’s perspective, is to achieve smooth and efficient transitions between different health care providers. Current research shows that the patient’s involvement in discharge planning before leaving the hospital is often deficient. Furthermore, nurses at the hospital ward experience discharge planning as stressful work.   The aim of the improvement work was to identify and implement measures for improving discharge process. The method underlying this improvement work is referred to as “the improvement ramp”, and an exploratory case study was carried out. Data was collected, by interviewing health professionals, and analysed using qualitative content analysis.   The results of the implemented measures show no measurable improvements in the discharge process. However, the interviews indicate that health professionals experienced improvements in their daily routines. The conclusion was that the improvement work was valuable and resulted in a developed learning although the measurements didn’t capture all results. The choice of area for improvement was of great importance because it affected the participants' motivation.
148

Oddlužení se zaměřením na společné oddlužení manželů / Discharge from debts focusing on discharge from debts for spouses

Sedláčková, Magdalena January 2013 (has links)
The purpose of my thesis is to analyze the institute discharge of the debt as the way of solution of bankruptcy according to Act No. 182/2006 Coll., on Bankruptcy and its solution (Insolvency Act). The thesis concerns all the phases of the process of discharge of the debt, from the proposal of permission of the discharge of the debt until its accomplishment. The thesis focuses on relevant legal regulation and case law. I also present the institute of discharge of debt of husband and wife which is quite often used without any legal support. The thesis is divided into five chapters. The Chapter One deals with the proposal of permission of the discharge of the debt. It examines particularly the subjects who are authorized to submit it and possible decisions of the court including the reasons for its dismissal. In the next Chapter I investigate two possible ways of discharge of the debt, the liquidation of the debtor's assets and monthly payment of a specific amount. For each type the affected assets and advantages and drawbacks for the debtor are described. The possibility for creditors to vote about type of discharge of the debt is also discussed. The Chapter Three relates to the decision of approval of discharge of the debt which has specific essentials and effects and means a lot of duties for the...
149

Modelagem de séries fluviométricas para o semi-árido brasileiro via redes neurais artificiais / Discharge time series modeling applied to rivers from Northeast of Brazil using artificial neural networks

Teixeira, Fábio Lavor 28 March 2003 (has links)
As Redes Neurais Artificiais (RNAs) vêm sendo empregadas com cada vez mais sucesso em diversas áreas de pesquisa, no campo da engenharia e em outros campos diversos. Neste trabalho foram modeladas séries fluviométricas relativas às afluências a quatro reservatórios, localizados em quatro bacias hidrográficas distintas que compõem a Bacia Metropolitana de Fortaleza, Ceará, Brasil. Tais afluências apresentam peculiaridades relativas à ocorrência de magnitudes nulas, que dificultam sua modelagem através dos convencionais modelos estatísticos da família Box-Jenkins. Neste estudo foram trabalhadas duas abordagens distintas, a primeira univariada, em que cada série era modelada de forma individual, e a segunda multivariada, em que as séries fluviométricas eram modeladas simultaneamente. Os resultados obtidos, segundo ambas as modelagens, demonstram que a técnica apresenta potencial para a aplicação pretendida. Estudos futuros merecem ser desenvolvidos ainda no sentido de verificar a melhor maneira de se enquadrar a componente aleatória nas séries sintéticas produzidas via RNAs. / Artificial Neural Networks (ANNs) are being used more and more in many different fields of research, in engineering applications or other applications. This research deals with modeling of inflows to four reservoirs, located in different watersheds that belong to the Metropolitan Watershed of Fortaleza city, Brazil. These discharge sequences have particular characteristics in that they have frequent occurence of null discharges which makes it difficult to use traditional statistical models such as those Box-Jenkis family. Two different modeling approaches were adopted in this study, the first univariate, in which each time series was modeled individually, and the second multivariate, in which the four time series were modeled simultaneously. The results from the both approaches show that the technique has potential for use in water resources planning and management. Future studies are required to propose better means of incorporing the random component in the generation of synthetic time series through ANNs.
150

A Randomized Controlled Trial of a Discharge Nursing Intervention to Promote Self-Regulation of Care for Early Discharge Interventional Cardiology Patients

Gould, Kathleen Ahern January 2009 (has links)
Thesis advisor: Barabara Hazard / This randomized controlled trial (RCT) examined a discharge nursing intervention (DNI) aimed at promoting self-regulation of care for early discharge interventional cardiology patients. The purpose of this study was to compare medication adherence, patient satisfaction, use of urgent care, and illness perception in patients with cardiovascular disease (CVD) undergoing interventional revascularization procedures who receive usual care and those who receive a DNI. The Common Sense Model (CSM) of illness representation provided the theoretical foundation for this study. The CSM is a cognitive parallel processing model that draws relationships between illness representation, coping methods, and illness outcomes to help explain the process by which people make sense of their illness. Intervention research aimed at life style changes to reduce secondary events after treatment for CVD is needed to guide evidence based care. Treatment for CVD has shifted from surgical repair with prolonged hospitalizations to interventional procedures requiring shorter hospital stays. This trend reduces nursing time to monitor complications and provide education about medication management and lifestyle changes. Patients recover in short stay areas and return home within hours or one to two days of the procedure. Cardiac disease is then managed as a chronic, but often stable condition. With this change in the delivery of care, several trends have emerged that have implications for quality nursing care and patient outcomes: a) the burden of care shifts from the hospital setting to home, b) patients are discharged without extensive education about complications and disease management, c) the occurrence of secondary events and disease progression remain a valid threat, and d) nurses with expert practice are in a unique position to assist patients and families with CVD management. This study addressed the following questions. 1. Do patients receiving the nursing intervention differ significantly from those receiving usual care on medication adherence? 2. Do patients receiving the nursing intervention differ significantly from those receiving usual care on patient satisfaction? 3. Is there a significant difference in the utilization of urgent care between those patients receiving the nursing intervention when compared to those patients receiving usual care? 4. Does a difference exist between the patients receiving the nursing intervention and those patients receiving usual care on illness perception, as measured by seven components of the IPQ-R: time line (acute and chronic), consequence, personal control, treatment (cure) control, illness coherence, timeline (cyclical), and emotional representations? Purposive sampling was used to select a sample of patients admitted for interventional procedures at an academic teaching hospital. One hundred and fifty four patients were and randomized into control and experimental groups. Final analyses included data from 129 patients. Sixty-four participants in the experimental group received the DNI which included: 1) additional written information about taking medications, 2) a medication pocket card, 3) a list of 3 cardiac internet sites,and 4) a phone call, 24 hours post procedure, from an expert cardiac nurse to review discharge instructions. Sixty-five participants in the control group received usual care. Analyses on four outcome measures, medication adherence, use of urgent care, patient satisfaction, and illness perception, revealed one statistically significant result. Participants in the experimental group, receiving the DNI, scored significantly higher than the control group on one measure, the timeline (acute/chronic) component of illness perception (p = .006) indicating a greater appreciation of the chronicity of their disease. Otherwise, there were no significant group differences found. This study provides support for nursing intervention research guided by self-regulation theory that examines the patient's perception of illness. Patients with cardiac disease who received the DNI were statistically more likely to acknowledge that their illness would last a long time. This awareness, may improve adherence to a prescribed regimen of medication and lifestyle modification. Nursing interventions guided by an understanding of patients' belief that their cardiovascular disease is chronic will add to the body of knowledge that informs providers about decisions patients make concerning medication adherence and lifestyle modifications. However, the results underscore the limitations of adding additional discharge care to this population of patients to improve medication adherence, use of urgent care, and patient satisfaction. Future research should include a longitudinal study to examine how patients who perceive their disease to be chronic in nature managed their medications and care decisions at home. / Thesis (PhD) — Boston College, 2009. / Submitted to: Boston College. Connell School of Nursing. / Discipline: Nursing.

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