Made available in DSpace on 2014-06-11T19:35:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-12Bitstream added on 2014-06-13T20:26:17Z : No. of bitstreams: 1 castrojunior_j_dr_botfm.pdf: 761536 bytes, checksum: 8c6353cd6eec74b90409bf5498e8e3f5 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Durante anestesia geral com intubação traqueal para manutenção das vias aéreas, a umidificação e o aquecimento artificial dos gases inalados são essenciais para a prevenção de alterações na mucosa traqueobrônquica e diminuição do risco de hipotermia não intencional durante a cirurgia. A estação de trabalho de anestesia Primus (Dräger, Lübeck, Alemanha) tem placa de metal aquecida, situada na parte expiratória do circuito, para a prevenção da condensação de água no sistema respiratório. Esta placa aquecida também pode ajudar na manutenção da temperatura do gás no circuito respiratório em valores adequados. O presente estudo teve como objetivo a determinação da temperatura esofágica e da temperatura e umidade dos gases anestésicos no circuito respiratório do aparelho Primus da Dräger usando baixo fluxo de gases frescos (FGF) associado ou não ao uso do permutador de calor e umidade (PCU). Participaram do estudo trinta pacientes adultas com estado físico ASA I e II submetidas a cirurgias ginecológicas eletivas. As pacientes foram distribuídas aleatoriamente em dois grupos sob ventilação com baixo FGF de 1 L.min-1 com ou sem PCU durante anestesia geral com sistema circular respiratório com absorvedor de CO2. Todas as pacientes receberam aquecimento ativo da superfície cutânea por meio de manta térmica colocada sobre os membros inferiores. A temperatura e umidades relativa e absoluta dos Introdução e Literatura 6 gases e a temperatura esofágica foram medidas aos 15 minutos (tempo controle) após instalação do sistema de ventilação nas pacientes e, então, a cada 30 minutos até 120 minutos após o tempo controle. A temperatura e a umidade relativa e absoluta dos gases inalados no grupo com baixo FGF ao PCU apresentaram valores mais elevados comparados aos do grupo com baixo FGF sem PCU (p < 0,05). Não houve redução na temperatura... / In general anesthesia with endotracheal intubation, maintenance of airway humidity and temperature is important to prevent damage to the tracheobronchial mucosa and to risk the drop in body temperature during surgery. The anesthesia Primus’s work station (Dräger, Lübeck, Germany) has a built-in hot plate coupled to heat expired gases to prevent water condensation in the breathing system, but this heating plate also may help maintaining gas temperature in the respiratory system at adequate levels. In the present study, we measured the inspired gas temperature and humidity of the anesthetic circuit in the Dräger Primus machine using low fresh gas flow with or without a heat and moisture exchanger (HME). Thirty adult ASA I and II women patients scheduled to gynaecologic surgeries were randomly assigned into two groups to received low fresh gas flow of 1 L.min-1 with or without HME in the circle anesthesia system. All patients received active skin-surface warming with a specific blanket from a warming device. Relative humidity, absolute humidity, and temperature of inspired gases and esophageal temperature were measured at 15 min and then every 30 min up to 120 min after the installation of the respiratory system. There was a significantly higher relative humidity, absolute humidity and temperatures of the inspired gases in the HME group compared to without HME group (p < 0.05). The esophageal temperature did not decrease in Introdução e Literatura 8 the group HME (p > 0.05), but decreased significantly intraoperatively in without HME group (p < 0.05). Low-flow with the breathing system of the Dräger Primus anesthesia workstation have inherent humidifying properties sufficient to reduce the risk of respiratory tract dehydration only after 90 minutes of anaesthesia. The addition of HME improves the inspiratory absolute humidity, relative humidity and temperature of the anesthetic... (Complete abstract click electronic access below)

Orientador: Jose Reinaldo Cerqueira Braz / Banca: Regina Helena Garcia Martins / Banca: Flora Margarida Barra Bisinotto / Banca: Luiz Vicente Garcia / Banca: Artur Udelsmann / Resumo: Durante anestesia geral com intubação traqueal para manutenção das vias aéreas, a umidificação e o aquecimento artificial dos gases inalados são essenciais para a prevenção de alterações na mucosa traqueobrônquica e diminuição do risco de hipotermia não intencional durante a cirurgia. A estação de trabalho de anestesia Primus (Dräger, Lübeck, Alemanha) tem placa de metal aquecida, situada na parte expiratória do circuito, para a prevenção da condensação de água no sistema respiratório. Esta placa aquecida também pode ajudar na manutenção da temperatura do gás no circuito respiratório em valores adequados. O presente estudo teve como objetivo a determinação da temperatura esofágica e da temperatura e umidade dos gases anestésicos no circuito respiratório do aparelho Primus da Dräger usando baixo fluxo de gases frescos (FGF) associado ou não ao uso do permutador de calor e umidade (PCU). Participaram do estudo trinta pacientes adultas com estado físico ASA I e II submetidas a cirurgias ginecológicas eletivas. As pacientes foram distribuídas aleatoriamente em dois grupos sob ventilação com baixo FGF de 1 L.min-1 com ou sem PCU durante anestesia geral com sistema circular respiratório com absorvedor de CO2. Todas as pacientes receberam aquecimento ativo da superfície cutânea por meio de manta térmica colocada sobre os membros inferiores. A temperatura e umidades relativa e absoluta dos Introdução e Literatura 6 gases e a temperatura esofágica foram medidas aos 15 minutos (tempo controle) após instalação do sistema de ventilação nas pacientes e, então, a cada 30 minutos até 120 minutos após o tempo controle. A temperatura e a umidade relativa e absoluta dos gases inalados no grupo com baixo FGF ao PCU apresentaram valores mais elevados comparados aos do grupo com baixo FGF sem PCU (p < 0,05). Não houve redução na temperatura... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In general anesthesia with endotracheal intubation, maintenance of airway humidity and temperature is important to prevent damage to the tracheobronchial mucosa and to risk the drop in body temperature during surgery. The anesthesia Primus's work station (Dräger, Lübeck, Germany) has a built-in hot plate coupled to heat expired gases to prevent water condensation in the breathing system, but this heating plate also may help maintaining gas temperature in the respiratory system at adequate levels. In the present study, we measured the inspired gas temperature and humidity of the anesthetic circuit in the Dräger Primus machine using low fresh gas flow with or without a heat and moisture exchanger (HME). Thirty adult ASA I and II women patients scheduled to gynaecologic surgeries were randomly assigned into two groups to received low fresh gas flow of 1 L.min-1 with or without HME in the circle anesthesia system. All patients received active skin-surface warming with a specific blanket from a warming device. Relative humidity, absolute humidity, and temperature of inspired gases and esophageal temperature were measured at 15 min and then every 30 min up to 120 min after the installation of the respiratory system. There was a significantly higher relative humidity, absolute humidity and temperatures of the inspired gases in the HME group compared to without HME group (p < 0.05). The esophageal temperature did not decrease in Introdução e Literatura 8 the group HME (p > 0.05), but decreased significantly intraoperatively in without HME group (p < 0.05). Low-flow with the breathing system of the Dräger Primus anesthesia workstation have inherent humidifying properties sufficient to reduce the risk of respiratory tract dehydration only after 90 minutes of anaesthesia. The addition of HME improves the inspiratory absolute humidity, relative humidity and temperature of the anesthetic... (Complete abstract click electronic access below) / Doutor

付記する学位プログラム名: グローバル生存学大学院連携プログラム / 京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21058号 / 工博第4422号 / 新制||工||1687(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 寶 馨, 教授 堀 智晴, 准教授 佐山 敬洋 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

Yes / This study assesses experimentally the role of gas viscosity in controlling the minimum film thickness in slot coating in both the slot over roll and tensioned web modes. The minimum film thickness here is defined with respect to the onset of air entrainment rather than rivulets, the reason being that rivulets are an extreme form of instabilities occurring at much higher speeds. The gas viscosity effects are simulated experimentally by encasing the coaters in a sealed gas chamber in which various gases can be admitted. An appropriate choice of two gases was used to compare performances: air at atmospheric pressure and helium at sub-ambient pressure (25mbar), which we establish has a significantly lower “thin film” viscosity than atmospheric air. A capacitance sensor was used to continuously measure the film thickness on the web, which was ramped up in speed at a fixed acceleration whilst visualizations of the film stability were recorded through a viewing port in the chamber. The data collected show clearly that by coating in rarefied helium rather that atmospheric air we can reduce the minimum film thickness or air/gas entrainment low-flow limit. We attribute this widening of the stable coating window to the enhancement of dynamic wetting that results when the thin film gas viscosity is reduced. These results have evident practical significance for slot coating, the coating method of choice in many new technological applications, but it is their fundamental merit which is new and one that should be followed with further data and theoretical underpinning.

No description available.

A principal ecological role proposed for the hyporheic zone is as a refugium that promotes benthic invertebrate survival during adverse conditions in the surface stream. Whilst a growing body of work has examined use of this hyporheic refugium during hydrological extremes (spates, streambed drying), little research has considered variation in refugium use over prolonged periods including contrasting conditions of surface flow. In this thesis, benthic invertebrate use of the hyporheic refugium is considered at monthly intervals over a five-month period of variable surface flow, at nine sites in two groundwater-dominated streams, the River Lathkill (Derbyshire) and the River Glen (Lincolnshire). Conditions identified as potential triggers of refugium use included a flow recession and a high-magnitude spate on the Lathkill, and small spates and a decline in flow preceding localised streambed drying on the Glen. During flow recession, reductions in submerged habitat availability and concurrent increases in benthic population densities were dependent on channel morphology. An unusual paired benthic-hyporheic sampling strategy allowed the type of refugium use (active migration, passive inhabitation) to be inferred from changes in hyporheic abundance and the hyporheic proportion of the total population. Using this approach, evidence of active migrations into the hyporheic zone use was restricted to two instances: firstly, Gammarus pulex (Amphipoda: Crustacea) migrated in response to habitat contraction and increased benthic population densities; secondly, migrations of Simuliidae (Diptera) were associated with low-magnitude spates. Refugium use was site-specific, with refugial potential being highest at sites with downwelling water and coarse sediments. A conceptual model describing this spatial variability in the refugial capacity of the hyporheic zone is developed for low flow conditions. In some cases, hyporheic refugium use was apparently prevented by disturbance-related factors (rapid onset, high magnitude) regardless of the refugial potential of the sediments. The extension of the hyporheic zone's refugial role to include low flows highlights the need to explicitly protect the integrity of hydrologic exchange in river rehabilitation schemes. However, the limited capacity of the hyporheic refugium emphasizes the additional importance of maintaining habitat heterogeneity including multiple instream refugia.

A certain amount of water is required for a mine site located in Turgutlu in Western Turkey to be used in mining processes. The purpose of this study is to assess the impacts associated with meeting water supply requirements for the mine. Scope of the study involves determination of the alternative water resources, the assessment of impacts associated with each resource and the selection of the most feasible alternative in the aspect of environmental and technical effects. Three alternatives suggested to supply mine process water are surface water, groundwater and reuse of waste water of Turgutlu town after treatment. A low flow analysis of Gediz River was conducted for the evaluation of the surface water. For the groundwater alternative, Turgutlu-Salihli aquifer model was established using MODFLOW 2009.1 software and the impacts on groundwater resources were evaluated. The evaluation of the last alternative, reuse of waste water of Turgutlu after treatment, was based upon the amount of waste water generated and treatment needed. Results of the alternatives show that each alternative is applicable to supply the required water to the mine site. However, the storage of the Gediz River water in a v small dam in wet seasons to be used later in dry seasons and the reuse of waste water of Turgutlu after treatment are the alternatives with least impacts on existing water users and related ecosystems.

Understanding the mechanisms of cardiovascular disease progression is essential in developing novel therapies to combat this disease that contributes to 1 in 3 deaths in the United States every year. Endothelial dysfunction and its effects on vessel growth and remodeling are key factors in the progression and localization of atherosclerosis. Much of our understanding in this area has come from in-vivo and in-vitro experiments however perfused organ culture systems provide an alternative approach. Organ culture systems can provide a more controlled mechanical and biochemical environment compared to in-vivo models. This study focused on furthering development of this organ culture model by introducing a novel device to produce flow waveforms at the high frequencies and low mean flows seen in the mouse model. The device is capable of monitoring pressure, flow, diameter, and nitric oxide release. Each individual mechanism in the system was integrated via a computer using a custom Labview interface. The performance of the device was characterized by developing physiologic, physiologic-oscillatory, low, low-oscillatory waveforms and sinusoidal waveforms at frequencies ranging from 1-10 Hz. Overall this system provides a robust model to test the effects of flow on various biological markers both in real-time and after culture.

Water management and environmental protection is vulnerable to extreme low flows during streamflow droughts. During the last decades, in most rivers of Central Europe summer runoff and low flows have decreased. Discharge projections agree that future decrease in runoff is likely for catchments in Brandenburg, Germany. Depending on the first-order controls on low flows, different adaption measures are expected to be appropriate. Small catchments were analyzed because they are expected to be more vulnerable to a changing climate than larger rivers. They are mainly headwater catchments with smaller ground water storage. Local characteristics are more important at this scale and can increase vulnerability. This thesis mutually evaluates potential adaption measures to sustain minimum runoff in small catchments of Brandenburg, Germany, and similarities of these catchments regarding low flows. The following guiding questions are addressed: (i) Which first-order controls on low flows and related time scales exist? (ii) Which are the differences between small catchments regarding low flow vulnerability? (iii) Which adaption measures to sustain minimum runoff in small catchments of Brandenburg are appropriate considering regional low flow patterns? Potential adaption measures to sustain minimum runoff during periods of low flows can be classified into three categories: (i) increase of groundwater recharge and subsequent baseflow by land use change, land management and artificial ground water recharge, (ii) increase of water storage with regulated outflow by reservoirs, lakes and wetland water management and (iii) regional low flow patterns have to be considered during planning of measures with multiple purposes (urban water management, waste water recycling and inter-basin water transfer). The question remained whether water management of areas with shallow groundwater tables can efficiently sustain minimum runoff. Exemplary, water management scenarios of a ditch irrigated area were evaluated using the model Hydrus-2D. Increasing antecedent water levels and stopping ditch irrigation during periods of low flows increased fluxes from the pasture to the stream, but storage was depleted faster during the summer months due to higher evapotranspiration. Fluxes from this approx. 1 km long pasture with an area of approx. 13 ha ranged from 0.3 to 0.7 ls depending on scenario. This demonstrates that numerous of such small decentralized measures are necessary to sustain minimum runoff in meso-scale catchments. Differences in the low flow risk of catchments and meteorological low flow predictors were analyzed. A principal component analysis was applied on daily discharge of 37 catchments between 1991 and 2006. Flows decreased more in Southeast Brandenburg according to meteorological forcing. Low flow risk was highest in a region east of Berlin because of intersection of a more continental climate and the specific geohydrology. In these catchments, flows decreased faster during summer and the low flow period was prolonged. A non-linear support vector machine regression was applied to iteratively select meteorological predictors for annual 30-day minimum runoff in 16 catchments between 1965 and 2006. The potential evapotranspiration sum of the previous 48 months was the most important predictor (r²=0.28). The potential evapotranspiration of the previous 3 months and the precipitation of the previous 3 months and last year increased model performance (r²=0.49, including all four predictors). Model performance was higher for catchments with low yield and more damped runoff. In catchments with high low flow risk, explanatory power of long term potential evapotranspiration was high. Catchments with a high low flow risk as well as catchments with a considerable decrease in flows in southeast Brandenburg have the highest demand for adaption. Measures increasing groundwater recharge are to be preferred. Catchments with high low flow risk showed relatively deep and decreasing groundwater heads allowing increased groundwater recharge at recharge areas with higher altitude away from the streams. Low flows are expected to stay low or decrease even further because long term potential evapotranspiration was the most important low flow predictor and is projected to increase during climate change. Differences in low flow risk and runoff dynamics between catchments have to be considered for management and planning of measures which do not only have the task to sustain minimum runoff. / Sowohl Gewässermanagement als auch die Gewässerökologie können durch extreme Niedrigwasserereignisse stark betroffen sein. In den letzten Jahrzehnten haben sowohl der Abfluss während der Sommermonate als auch die Niedrigwasserabflüsse in den meisten Flüssen Zentraleuropas abgenommen. Projektionen des zukünftigen Abflusses lassen einen weiteren Rückgang der Abflüsse aus Einzugsgebieten Brandenburgs erwarten. Anpassungsmaßnahmen zur Stützung von Niedrigwasserabflüssen müssen den hydrologischen Prozessen gerecht werden. In dieser Arbeit werden Kopfeinzugsgebiete mit kleineren Grundwasserspeichern betrachtet, weil sie anfälliger gegenüber dem Klimawandel erscheinen als größere. Lokale Gegebenheiten können darüber hinaus ihre Vulnerabilität erhöhen. In dieser Arbeit werden Ergebnisse über die ähnlichkeit von kleinen Einzugsgebieten verwendet, um geeignete Anpassungsmaßnahmen zur Stützung von Niedrigwasserabflüssen herauszuarbeiten. Folgende Leitfragen werden bearbeitet: (i) Was sind die maßgeblichen Prozesse und Zeitskalen, die zu Niedrigwasserabflüssen führen? (ii) Wie unterscheiden sich die Einzugsgebiete bezüglich ihrer Vulnerabilität? (iii) Was sind geeignete Anpassungsmaßnahmen unter Berücksichtigung der vorherrschenden Prozesse und ihrer räumlichen Muster? Mögliche Anpassungsmaßnahmen können in drei Kategorien unterteilt werden: (i) Landnutzungsänderungen, änderungen der Feldbewirtschaftung und künstliche Grundwasseranreicherung führen zur Erhöhung der Grundwasserneubildung und somit des Basisabflusses. (ii) Talsperren, Seen, Teiche und ein entsprechendes Wassermanagement in Feuchtgebieten eignen sich zur Wasserspeicherung und regulierten Wasserabgabe. (iii) Maßnahmen bei deren Planung Wissen über Niedrigwasserabflüsse einfließen muss, aber die Stützung von Niedrigwasserabflüssen nicht die einzige Aufgabe ist (Siedlungswassermanagement, Abwassermanagement und Wasserüberleitungen zwischen Einzugsgebieten). Darüber hinaus wurde die Effektivität ufernaher Grundwasseranreicherung durch bestehende Bewässerungsgräben explizit an einem Standort unter Verwendung des Models Hydrus-2D quantifiziert. Hohe Wasserstände in den Gräben und das Unterbrechen der Wassereinleitung führten zu einer Niedrigwasseraufhöhung. Im Sommer wurde der Wasserspeicher wegen der Verdunstung schneller verbraucht. Je nach Szenario betrug die Niedrigwasseraufhöhung, die von der ca. 1 km langen und 13 ha großen Fläche ausging, zwischen 0.3 und 0.7 l/s. Eine Vielzahl solcher dezentraler Maßnahmen wären für eine deutliche Stützung der Niedrigwasserabflüsse in mesoskaligen Einzugsgebieten notwendig. Das Niedrigwasserrisiko sowie meteorologische Niedrigwasserprädiktoren wurden vergleichend analysiert. Der tägliche Abfluss aus 37 Einzugsgebieten zwischen 1991 und 2006 wurde mittels einer Hauptkomponentenanalyse ausgewertet. Der Abfluss in Südost Brandenburg ging klimabedingt stärker zurück. Das Niedrigwasserrisiko war in der Region östlich Berlins als Folge des kontinentaleren Klimas und der lokalen geohydrologischen Verhältnisse am größten. Diese Einzugsgebiete zeigten einen relativ schnellen Abflussrückgang während der Sommermonate und eine längere Niedrigwasserperiode. Darüber hinaus wurde eine nichtlineare Support Vektor Machine Regression zur iterativen Bestimmung der meteorologischen Prädiktoren für den jährlichen Niedrigwasserabfluss im 30-Tage Mittel in 16 Einzugsgebieten zwischen 1965 und 2006 durchgeführt. Die potentielle Verdunstungshöhe der vorhergegangenen 48 Monate war der wichtigste Prädiktor (r²=0.28). Die potentielle Verdunstungshöhe der vorhergegangenen 3 Monate sowie die Niederschlagshöhe der vorhergegangenen 3 Monate und des letzten Jahres verbesserten die Modellgüte zusätzlich (r²=0.49, für alle vier Prädiktoren). Die Modellgüte war höher in Einzugsgebieten mit geringer Abflussspende und gedämpftem Abflussverhalten. In Einzugsgebieten mit hohem Niedrigwasserrisiko war die potentielle Langzeitverdunstung wichtiger, um Niedrigwasserabflüsse zu erklären. In Einzugsgebieten mit hohem Niedrigwasserrisiko östlich von Berlin und deutlichem Abflussrückgang im Südosten Brandenburgs besteht der höchste Anpassungsbedarf. Maßnahmen zur Erhöhung der Grundwasserneubildung sollten bevorzugt werden. Einzugsgebiete mit hohem Niedrigwasserrisiko haben verhältnismäßig tiefe Grundwasserstände, was eine Erhöhung der Grundwasserneubildung in den höher gelegenen Neubildungsgebieten möglich und sinnvoll macht. Es ist davon auszugehen, dass Niedrigwasserabflüsse weiterhin niedrig bleiben oder sogar weiter fallen werden, da die potentielle Langzeitverdunstung der wichtigste Prädiktor war und Klimamodelle einen weiteren Anstieg dieser projizieren. Des Weiteren sind die Ergebnisse dieser Arbeit wichtig für die integrierte Planung von Maßnahmen, die nicht ausschließlich die Stützung von Niedrigwasserabflüssen zur Aufgabe haben.

L'estimation d'indices d'étiage est d'une grande importance pour une meilleure connaissance de la ressource en eau disponible et en déduire des règles de gestion de cette ressource et des risques associés. Idéalement, ces indices sont calculés en sites jaugés à partir de longues chroniques de débits mesurés. En sites non jaugés, ces indices doivent être estimés. Cette thèse s'inscrit dans le projet d'amélioration de l'outil informatique " LoiEau " utilisé par les DREAL et les Agences de l'eau. Le principal objectif est de développer un modèle hydrologique simple et flexible pour estimer tous les indices d'étiage souhaités à des intervalles de temps journaliers ou supérieurs en sites non jaugés. La simplicité du modèle repose sur l'hypothèse forte que deux paramètres plus facilement régionalisables suffisent à estimer les indices avec une précision voulue. Cette précision dépend de la fonction objectif qu'il a fallu adapter aux faibles débits pour caler convenablement les paramètres du modèle sur des sites jaugés. Le modèle se veut flexible dans le sens où il est applicable à une large variété de bassins versants. Il a été comparé au modèle journalier à quatre paramètres GR4J et au modèle mensuel à deux paramètres LoiEau en s'intéressant aussi à la façon de régionaliser les paramètres. Des comparaisons ont également été réalisées avec une méthode d'estimation dite stochastique d'un indice d'étiage classique. Ces travaux montrent le potentiel du modèle à deux paramètres et l'avantage du pas de temps journalier, la variabilité temporelle des précipitations n'étant pas sans conséquence sur l'estimation de débits moyens en raison de la non-linéarité des modèles pluies-débits. / Estimating low-flow indices is of paramount importance to understand low flows and to manage water resources and risk assessments. These indices are derived from time-series of river discharges that are measured at gauged sites over long periods. At ungauged sites, the indices must be estimated. This research work is part of a project to improve “LoiEau”, a software package that is used by French regional environmental or water agencies. The main objective is to develop a simple and flexible rainfall-runoff model to simulate low-flow indices of ungauged sites at daily or longer time intervals. The model simplicity relies on the strong assumption that two free parameters are sufficient to provide accurate enough estimates of low-flow indices, yet making easier the regionalisation of models. The model accuracy depends on the objective function that is used to calibrate model parameters on gauged sites and had to be adapted to low-flow simulations. The model is flexible in the sense that it is designed to fit to a wide variety of catchments and hydro-meteorological behaviours. This model was compared with GR4J, a daily rainfall-runoff model which involves four parameters, and LoiEau, a monthly model. Comparisons were also carried out with a stochastic estimation method applied to a specific low-flow index. This research work shows the potential of the two-parameter model, but also the advantage of a daily time step to account for the temporal variability of precipitations, which is not without consequence on the assessment of average discharges due to the nonlinearity of rainfall-runoff models.