Teses / dissertações sobre o tema "Solution depth"

<p> The behavior of many systems of practical interest in communications and other areas is well modeled by a single server exponential queueing system in which the arrival and service rates are dependent upon the state of a Markov chain, the dynamics of which are independent of the queue length. Formal solution to such models based on Neuts's matrix geometric approach have appeared frequently in the literature. A major problem in using the matrix geometric approach is the computation of the rate matrix, which requires the solution of a matrix polynomial. In particular, computational times appear to be unpredictable and excessive for many problems of practical interest. Alternative techniques which employ eigenanalysis have been developed. These techniques are polynomially bounded and yield results very quickly compared to iterative routines. On the other hand, the class of systems to which the eigenanalysis based techniques apply have been somewhat restricted. In this thesis, we modify the eigenanalysis approach initially presented in order to remove some of these restrictions.<br>Master of Science

In this thesis we have developed solutions to common issues regarding widefield microscopes, facing the problem of the intensity inhomogeneity of an image and dealing with two strong limitations: the impossibility of acquiring either high detailed images representative of whole samples or deep 3D objects. First, we cope with the problem of the non-uniform distribution of the light signal inside a single image, named vignetting. In particular we proposed, for both light and fluorescent microscopy, non-parametric multi-image based methods, where the vignetting function is estimated directly from the sample without requiring any prior information. After getting flat-field corrected images, we studied how to fix the problem related to the limitation of the field of view of the camera, so to be able to acquire large areas at high magnification. To this purpose, we developed mosaicing techniques capable to work on-line. Starting from a set of overlapping images manually acquired, we validated a fast registration approach to accurately stitch together the images. Finally, we worked to virtually extend the field of view of the camera in the third dimension, with the purpose of reconstructing a single image completely in focus, stemming from objects having a relevant depth or being displaced in different focus planes. After studying the existing approaches for extending the depth of focus of the microscope, we proposed a general method that does not require any prior information. In order to compare the outcome of existing methods, different standard metrics are commonly used in literature. However, no metric is available to compare different methods in real cases. First, we validated a metric able to rank the methods as the Universal Quality Index does, but without needing any reference ground truth. Second, we proved that the approach we developed performs better in both synthetic and real cases.<br>In questa tesi abbiamo sviluppato soluzioni a questioni comuni in materia di microscopia a campo largo. Abbiamo affrontato il problema della non omogeneità dell'intensità delle immagini acquisite e due forti limitazioni: l'impossibilità di acquisire immagini ad alto dettaglio rappresentative o dell'intero campione o di oggetti 3D con spessore non trascurabile. Per prima cosa abbiamo studiato le caratteristiche del problema denominato vignettatura, relativo alla distribuzione non uniforme del segnale di luce all'interno di ogni singola immagine. In particolare abbiamo proposto metodi dove la funzione di vignettatura è stimata utilizzando un insieme di immagini acquisite direttamente dal campione. In seguito, abbiamo studiato come risolvere il problema legato alla limitata dimensione del campo di vista della telecamera, al fine di essere in grado di acquisire una singola immagine ad alto ingrandimento rappresentativa dell'intera area del campione osservato. A questo scopo abbiamo sviluppato tecniche di mosaicatura in grado di operare on-line con l'acquisizione delle immagini. Partendo da una serie di immagini acquisite manualmente, abbiamo validato un approccio di registrazione in grado di creare velocemente un mosaico allineando accuratamente le singole immagini acquisite. Infine, abbiamo studiato come estendere virtualmente il campo di vista della telecamera lungo la terza dimensione, con lo scopo di poter ottenere singole immagini completamente a fuoco di oggetti 3D. Abbiamo proposto un metodo generale che non richiede alcuna informazione a priori. Per confrontare i risultati dei diversi metodi, in letteratura sono tipicamente usate diverse metriche comuni. Tuttavia nessuna metrica è in grado di confrontare diversi metodi usando immagini reali. In primo luogo abbiamo validato una metrica in grado di classificare i diversi metodi in accordo all'indice di qualità universale, ma senza bisogno di alcuna verità di riferimento. Poi abbiamo dimostrato che il metodo che abbiamo sviluppato risulta essere il migliore tra tutti quelli testati per estendere la profondità di fuoco.

Health-related disparities remain a persistent, serious problem across the nation's more than 60 million rural residents. Rural Populations and Health provides an overview of the critical issues surrounding rural health and offers a strong theoretical and evidence-based rationale for rectifying rural health disparities in the United States. This edited collection includes a comprehensive examination of myriad issues in rural health and rural health care services, as well as a road map for reducing disparities, building capacity and collaboration, and applying prevention research in rural areas. This textbook offers a review of rural health systems in Colorado, Kentucky, Alabama, and Iowa, and features contributions from key leaders in rural public health throughout the United States.

Sudden cardiac death (SCD) risk is reduced by implantable cardioverter defibrillator (ICD) use in appropriately selected patients. Established markers such as impairment of left ventricular function and QRS duration are non specific for arrhythmic death and therefore many patients receive ICD therapy from which they gain no benefit, either due to survival without arrhythmia or death from pump failure. Both myocardial scar and serum protein biomarkers have potential as SCD risk stratifiers, but novel solutions are needed to deliver non invasive tests that are suitable for point of care testing. The aims of this thesis were to explore novel assessment methods for the risk stratification of SCD, with particular focus on heart failure. Several approaches were chosen to explore these concepts: (i) meta-analysis to assess the utility of fragmented QRS, (ii) retrospective evaluation of ECG and CMR to assess ECG markers of repolarisation and (iii) QRS scoring, (iv) prospective evaluation of an automated QRS scoring algorithm to predict myocardial scar, (v) artificial intelligence machine learning techniques to develop and validate an algorithm capable to classifying ECG scar, and (vi) a novel high resolution proteomic technique to propose biomarkers of SCD risk, validated using ELISA (vii). The hypothesis is that novel clinical tools, encompassing technologies and techniques which could stretch across the clinical landscape from primary to specialised care services, can be identified as indicators of ICD benefit in patients at risk of SCD. My results indicate that simpler ECG markers such as T-peak-end, fQRS and QRS scoring have a significant association with myocardial scar, although the strength of association varies according to scar characteristics, and is not specific. The specificity of these markers for mode of death is also weak. Computerised algorithms can serve to speed up manual ECG scoring, whilst maintaining overall accuracy, but greatest potential is seen in using a novel marker, custom developed using artificial intelligence techniques. I also found that candidate serum biomarkers, predictive of death or ventricular arrhythmia, could be identified through high resolution proteomic techniques. Clinical and technical validation with ELISA is possible. Novel non invasive markers, such as serum proteins and computer ECG analysis may be valuable tools to improve risk prediction. The incremental benefit of these tools to determine prognosis, and select those who will most benefit from ICD therapy, can now be addressed by future prospective studies.

<p>This investigation is concerned with the determination of the sea state in terms of wave spectra. The phenomenum was calculated for two different bathymetries.</p> <p> The purpose is to develop a finite difference method with an upwind differencing scheme to g solve several formulations of the wave action conservation equation. The computations were done in the wave number space and the frequency direction space. For the case of a beach with constant slope the results were compared with the analytical solution. For the case of an elliptical submerged shoal, they were compared with experimental data. </p> <p>The results of the computer code showed a fairly good qualitative agreement with the actual values for a smooth distribution of input energy.<br>Master of Science

The research presented in this thesis addresses a number of challenges related to rock mass transportation in deep underground mines. In particular, high energy consumption and high exhaust gas emissions from diesel and electric LHDs, the effects of ore pass loss on the loading, hauling and dumping operations due to increasing stresses and increasing costs due to the longer vertical transportation of the rock masses. These critical challenges have been identified by a literature review and analysis of data collected from 15 international deep mines. In order to answer the formulated research questions, three studies on various issues related to rock mass transportation in deep underground mines were made, and the analysis was performed mainly using discrete event simulation. The thesis presents a study of energy consumption and exhaust gas emissions from diesel and electric LHDs with similar bucket sizes. The results show the possible energy savings and a decrease in CO2 emissions when using electric LHDs instead of diesel ones. The thesis also presents a study of the effects of ore pass loss on LHD operations and on the mine production. Maintaining the production with a lower number of operational ore pass structures by increasing the number of LHDs can have a negative effect on the production. This is because an increased number of LHDs in operation will results in increased waiting times for the LHDs and cause variations in the production rate. These variations can be large, causing severe consequences if not managed correctly. The results also show the importance of developing alternative plans for underground loading and hauling operations in case of an ore pass loss. Transportation of rock, especially when mining depth increases, is often associated with high costs and long transportation times. To decrease the amount of unnecessary rock transportation, near-to-face sorting plants may be one alternative. In the thesis, a study was performed on a possible reduction in rock mass transportation to the surface when using this technique. The results conclude that near-to-face sorting plants could lower the environmental effects generated by unnecessary rock transportation to the surface.

Lungs donated after cardiac death (DCD) are an underutilized resource for a dwindling donor lung transplant pool. Our study investigates the potential of a novel preservation solution, Somah, to better preserve statically stored DCD lungs, for an extended time period, when compared to low-potassium dextran solution (LPD). We hypothesize that Somah is a metabolically superior organ preservation solution for hypothermic statically stored porcine DCD lungs, possibly improving lung transplant outcomes. Porcine DCD lungs (n = 3 per group) were flushed with and submerged in cold preservation solution. The lungs were stored up to 12 h, and samples were taken from lung tissue and the preservation medium throughout. Metabolomic and redox potential were analyzed using high performance liquid chromatography, mass spectrometry, and RedoxSYS (R), comparing substrate and pathway utilization in both preservation solutions. Glutathione reduction was seen in Somah but not in LPD during preservation. Carnitine, carnosine, and n-acetylcarnosine levels were elevated in the Somah medium compared with LPD throughout. Biopsies of Somah exposed lungs demonstrated similar trends after 2 h, up to 12 h. Adenosine gradually decreased in Somah medium over 12 h, but not in LPD. An inversely proportional increase in inosine was found in Somah. Higher oxidative stress levels were measured in LPD. Our study suggests suboptimal metabolic preservation in lungs stored in LPD. LPD had poor antioxidant potential, cytoprotection, and an insufficient redox potential. These findings may have immediate clinical implications for human organs; however, further investigation is needed to evaluate DCD lung preservation in Somah as a viable option for transplant.

Cette thèse s'est proposée au travers de l'analyse de gaz lors d'expériences de calorimétrie (calorimètre Tewarson et DSC) de remonter aux mécanismes de dégradation de l'électrolyte afin de permettre l'évaluation des risques d'un point de vue de la sécurité. Ce travail nous a permis de proposer un schéma réactionnel relatant les processus exothermiques "multi-étapes" se déroulant à l'interface graphite lithié/électrolyte (EC/DMC LiPFe) grâce à l'utilisation combinée de la DSC et de techniques analytiques telles que la GC/MS, la RMN ou l'ESI-HRMS. L'étude a pu mettre en exergue la réactivité de PF5 avec les composés de la SEI. Ce schéma établi, nous avons étudié les effets de la température de formation de la SEI, de l'ajout d'additifs dans l'électrolyte et du changement de sel de l'électrolyte sur ces processus exothermiques. Une étude détaillée a été effectuée pour le sel LiFSI. Des essais de combustion, à l'aide d'un calorimètre Tewarson, ont été réalisés pour plusieurs électrolytes, leurs solvants et pour des batteries utilisant deux sels d'électrolyte différents (LiPFe et LiFSI). Les conditions de combustion bien contrôlées ont permis de déterminer les paramètres incontournables dans l'évaluation des risques d'incendie, comme la puissance du feu, la chaleur et la vitesse de combustion ainsi que l'identification et la quantification des gaz toxiques. La composition, le ratio entre le carbonate organique linéaire et cyclique, joue un rôle important sur les phénomènes thermiques et la nature des gaz de combustion. Le sel d'électrolyte LiFSI a un impact sur le comportement au feu des électrolytes à base de ce sel et des prototypes de batterie utilisant ces électrolytes<br>Use of analytical techniques either alone or hyphenated in order to systematically trace the degradation mechanism of electrolytes used in LIB and thereby ensure a precise appraisal of their risk was at the center of this thesis. The thesis work enabled the detailed investigation of the multi-step exothermic phenomena that takes place at the lithiated graphite/electrolyte interface in the presence of 1M LiPFe in EC/DMC (1/1, %wt) using DSC along with other analytical tools such as GC/MS, GC/FTIR etc. The study was able to highlight the reactivity of the thermally generated PF5 with the SEI layer reference compounds. The effect of parameters such as formation temperature of the SEI layer, electrolyte composition including solvents, salts, and additives on the exothermic phenomena was investigated. An in-depth examination on the thermal reactivity of LiFSI sait using DSC, NMR, GC/MS, GC/FTIR, ESI-HRMS and chemical simulation tests were conducted. Combustion tests on numerous single solvents, solvent mixtures, electrolytes and lithium-ion cell prototypes including different salts (LiPFe and LiFSI) were perfonned using Tewarson calorimeter. Well controlled combustion conditions enabled the determination of a number of fire-induced rating indicators such as thermal threats (ignitability, power of the fire, effective beat of combustion, beat release rate. . . ) and Chemical threats (identification and quantification of toxic gases). Each electrolyte compounds (ratio between linear and cyclic carbonates, nature of the salt) was found to play an important role both on the thermal reactivity and combustion chemistry of solvents, electrolytes and cells

“Overworking to death” is a phenomenon that has been noticeable in developing countries. The cause of death is mainly through ischemic strokes. While the victims’ occupations differed, they all shared a common characteristic, being positioned in a sedentary work, ranging from IT workers to doctors. This project’s aim was to develop a product that prevented or decreased the strokes that derived from sedentary overwork. This was mainly tackled by preventing one of the three causes of developing blood props, slowed blood flow. In order to gather rich data of the phenomenon, a qualitative study was conducted in China, during two months. By doing an extensive structured sampling, information rich data could be gathered during a short period of time. Data were derived from observations, questionnaires and an interview, which then was interpreted to customer needs and the final product specification. The final product became a trouser with an in built dynamic compression mechanic, that can compress the veins mostly during sitting activities, in order to prevent blood stasis. The compression mechanic works like the Chinese finger trap; compressing the calves while sitting and stretching the legs forward. It is made only out of polysaccharides fibres; cotton and corn.<br>"Guolaosi" eller död från överarbete är ett fenomen som i regel uppkommer bland utvecklingsländer. Dödsorsaken är huvudsakligen genom stroke. Offrens yrken varierar allt från professorer, IT-arbetare till läkare. De delar dock en sak gemensamt; att arbeta under långa perioder stillasittande. Projektets mål var att utveckla en produkt som minskar dödliga följderna av sedentära överarbete, genom att förebygga en av de tre orsakerna för att utveckla blodproppar; saktad blodström. Målgruppen var då kineser av de yrken som hade tidigare drabbats av fenomenet. För att samla informationsrika data om fenomenet genomfördes en kvalitativ studie i Kina under två månader. Genom att göra en omfattande strukturerad provtagning kunde informationsrika data samlas under en kort tidsperiod. Fältstudien bestod av observationer, frågeformulär och en intervju, som då tolkades till kundbehov och eventuellt produktspecifikationen. Den slutliga produkten kom att bli ett par byxor med en inbyggd dynamisk komprimeringsmekanism, som kan komprimera venerna under sittande aktiviteter, för att förhindra saktad blodström. Kompressionsmekanismen fungerar som den kinesiska fingerfällan. Den komprimerar blodkärlen medan personen sitter och sträcker benen framåt. Produkten är konstruerad på så sätt att den kan tillverkas endast av polysackariders tråd, från bomull och majs. Vilket är lämpligt för Kinas lokala resurser.

INTRODUÇÃO: O transplante cardíaco é o melhor tratamento para a insuficiência cardíaca em sua fase terminal. A morte encefálica (ME) é responsável por causar instabilidade hemodinâmica e hipoperfusão tecidual, levando a alterações inflamatórias e disfunção miocárdica em potenciais dadores de órgãos. A solução salina hipertônica (SH) é um expansor de volume plamático capaz de restaurar a hemodinâmica, além de ter efeito imunomodulador. OBJETIVO: Em um modelo de ME, testamos a hipótese de que o tratamento com SH previne a disfunção do ventrículo esquerdo (VE) e a lesão miocárdica. MÉTODOS: A ME foi induzida em ratos Wistar anestesiados pela insuflação de um cateter balão implantado no espaço subdural, exceto nos animais falso-operados (FO; n = 6). Após a indução da ME, os animais controle receberam apenas solução salina convencional (controle; n = 6). Os animais tratados foram divididos aleatoriamente para receber SH (NaCl a 7,5%, 4 mL / kg) 1 min (SH1; n = 6) ou 60 min (SH60; n = 6) após indução da ME. A função cardíaca foi avaliada continuamente durante 6 h, pela análise da curva pressão-volume no VE. Os marcadores de lesão miocárdica, resposta inflamatória e as proteínas relacionadas à apoptose celular foram dosados no soro ou em fragmentos de tecido cardíaco por imuno-histoquímica ou ensaio-imuno-enzimático, quando apropriado. RESULTADOS: A ME associou-se à diminuição da função sistólica do VE, quando comparada ao grupo FO. A utilização de SH após a indução de ME provocou melhora da função sistólica do VE (pressão sistólica final, velocidade máxima de elevação da pressão no VE, volume sistólico, fração de ejeção, trabalho sistólico e débito cardíaco) 6 h mais tarde, quando comparado ao controle. No entanto, não foram observadas vantagens em relação ao relaxamento ventricular (velocidade máxima de queda da pressão no VE e tempo de relaxamento isovolumétrico - Tau) após o mesmo período. Além disso, quando comparado aos grupos em que houve ME, o tratamento com SH aumentou a expressão de proteína anti-apoptótica e diminuiu a expressão de moléculas de adesão vascular e fator de necrose tumoral alfa. Não foram observadas alterações histológicas ou de proteínas estruturais significativas entre os grupos. CONCLUSÃO: Os dados mostram que a SH melhora a função sistólica do VE e reduz o dano ao tecido miocárdico em ratos submetidos à ME, mesmo quando o tratamento foi realizado durante o processo desencadeado por este evento<br>BACKGROUND: Heart transplantation represents the most effective treatment for end-stage heart failure. Brain death (BD) is responsible for hemodynamic instability and organ hypoperfusion leading to inflammatory changes and myocardial dysfunction in potential organ donors. Hypertonic saline (HS) is a volume expander capable of restoring hemodynamics in addition to having an immunomodulatory effect. OBJECTIVE: In a rat model of BD, we tested the hypothesis that treatment with HS would prevent left ventricular (LV) dysfunction and myocardial injury. METHODS: BD was induced in anesthetized Wistar rats by inflating a subdurally placed balloon catheter, except in Sham operated animals (n=6). After BD induction, control animals received only common saline solution (n=6). Treated animals were randomly divided to receive HS (7.5% NaCl, 4mL/kg) 1 min (HS1; n=6) or 60 min (HS60; n=6) after BD induction. We continuously assessed cardiac function for 6h by LV pressure-volume analysis. Inflammatory response, markers of myocardium injury and cellular apoptosis related proteins were investigated in serum or tissue fragments by immunohistochemistry or enzyme-immune-assay when appropriated. RESULTS: Compared with Sham, BD was associated with decreased LV systolic and diastolic function. HS treatment after BD induction improved LV systolic function (end-systolic pressure, maximum rate of rise of LV pressure, stroke volume, ejection fraction, systolic work and cardiac output) 6h later when compared with Control. However, no ventricular relaxation advantages were observed (maximum rate of fall of LV pressure and time constant of LV pressure decay - Tau) after the same time. In addition, compared with BD groups HS treatment increased anti-apoptotic protein expression and decreased vascular adhesion molecule and tumor necrosis factor alfa expression. No significant histologic or structural proteins changes were observed between groups. CONCLUSION: Observed data show that HS improves LV systolic function and reduces myocardial tissue compromise in BD rats, even when the treatment was performed during the process triggered by this event

INTRODUÇÂO: A morte encefálica (ME) induz instabilidade hemodinâmica com hipoperfusão microcirculatória, desencadeando inflamação e disfunção de órgãos. OBJETIVO: Este estudo teve como objetivo investigar os efeitos da solução salina hipertônica (SH) 7,5% na evolução da resposta inflamatória no tecido mesentérico de ratos submetidos à ME. MÉTODOS: Ratos Wistar machos foram anestesiados e ventilados mecanicamente. A ME foi induzida pela insuflação rápida de um balão posicionado na cavidade intracraniana (Fogart 4F). Os ratos foram divididos aleatoriamente em: 1) Falso-operado, ratos submetidos aos procedimentos cirúrgicos e trepanação (FO, n=17); 2) Controle, ratos tratados com solução salina isotônica (NaCl 0,9%, 4 mL/kg) imediatamente após ME (CO, n=17); 3) Solução hipertônica 1, ratos tratados com solução hipertônica (NaCl 7,5%, 4 mL/kg) imediatamente após ME (SH1, n=17); 4) Solução hipertônica 60, ratos tratados com solução hipertônica 60 min após ME (SH60, n=17). Três horas após a indução da ME ou o término do procedimento cirúrgico para os animais do grupo FO, foram coletados os seguintes dados: (a) perfusão mesentérica, fluxo sanguíneo e interações leucócito-endotélio no mesentério, pela técnica de microscopia intravital; (b) expressão de proteínas de óxido nítrico sintase endotelial (eNOS), endotelina-1, P-selectina e molécula de adesão intercelular (ICAM)-1, por imunohistoquímica; (c) expressão gênica de eNOS e endotelina-1, por reação em cadeia da polimerase em tempo real (PCR); (d) concentrações séricas de citocinas, quimiocinas e corticosterona por meio de enzimaimunoensaio (ELISA). RESULTADOS: Todos os grupos submetidos a ME apresentaram um comportamento semelhante da pressão arterial, sendo observado um pico hipertensivo, seguido de período de hipotensão, logo após a insuflação do cateter intra-craniano. A proporção de pequenos vasos perfundidos foi diminuída no grupo CO (46%) em comparação com FO (74%, p=0,0039). A SH foi capaz de restaurar a proporção de vasos perfundidos (SH1=71%, p=0,0018). Não houve diferenças no fluxo sanguíneo mesentérico entre os grupos. A expressão proteica de eNOS aumentou significativamente em ratos com SH (SH1 e SH60, p=0,0002) em comparação ao grupo CO. Resultados semelhantes foram observados em relação à endotelina-1 (p < 0,0001). Não houve diferenças na expressão gênica de eNOS e endotelina-1. O aumento no número de leucócitos \"rollers\" (p=0,0015) e migrados (p=0,0063) foi observado no grupo CO em comparação com FO. Ratos com SH demonstraram redução significativa em todos os parâmetros da interação leucócito-endotélio. Com relação às moléculas de adesão, a expressão de ICAM-1 estava elevada no grupo CO em comparação com o FO, enquanto que o tratamento com SH diminuiu a expressão de ICAM-1 (SH1 e SH60, p=0,0002). CONCLUSÕES: O emprego da solução salina hipertônica melhorou a perfusão mesentérica, influenciou positivamente o metabolismo do óxido nítrico e reduziu a inflamação no mesentério, com diminuição da adesão e migração leucocitária, em ratos submetidos a ME<br>BACKGROUND: Brain death (BD) induces hemodynamic instability with microcirculatory hypoperfusion leading to increased organ inflammation and dysfunction. OBJETIVE: To investigate the effects of 7.5% hypertonic saline solution (HS) on the course of the inflammatory response in rats submitted to BD. METHODS: Male Wistar rats were anesthetized and mechanically ventilated. BD was induced by rapid inflation of intracranial balloon catheter (Fogart 4F). Rats were randomly divided in: 1) Sham-operated, rats submitted only to trepanation (SH, n=17); 2) Control, rats treated with normal saline solution (NaCl 0.9%, 4 mL/kg) immediately after BD (CO, n=17); 3) Hypertonic solution 1, rats treated with hypertonic solution (NaCl 7.5%, 4 mL/kg) immediately after BD (HS1, n=17); 4) Hypertonic solution 60, rats treated with hypertonic solution 60 min after BD (HS60, n=17). Hundred eighty minutes thereafter the following experiments were performed: (a) mesenteric perfusion, blood flow, and leukocyte-endothelial interactions, by intravital microscopy; (b) protein expression of endothelial nitric oxide synthase (eNOS), endothelin-1, P-selectin, and intercellular cell adhesion molecule (ICAM)-1, by immunohistochemistry; (c) gene expression of eNOS, and endothelin-1, by real-time polymerase chain reaction (PCR); (d) serum concentrations of cytokines, chemokines and corticosterone by enzyme-linked immunosorbent assay (ELISA). RESULTS: All BD groups presented similar hypertensive peak followed by hypotension. The proportion of perfused small vessels was decreased in CO group (46%) compared to SH (74%, p=0.0039). HS was able to restore the proportion of perfused vessels (HS1=71%, p=0.0018). There were no differences in mesenteric blood flow between groups. eNOS protein expression significantly increased in rats given HS (HS1, and HS60, p=0.0002). Similar results were observed regarding endothelin-1 (p < 0.0001). There were no differences in eNOS and endothelin-1 gene expression. Increased numbers of rolling (p=0.0015) and migrated (p=0.0063) leukocytes were observed in CO group compared to SH. Rats given HS demonstrated an overall reduction in leukocyte-endothelial interactions. Levels of ICAM-1 increased in CO group compared to SH, and decreased in HS-treated groups (p=0.0002). CONCLUSIONS: Hypertonic saline improves mesenteric perfusion, increased eNOS and endothelin-1 protein expression, and reduced inflammation by decreasing leukocyte adhesion and migration in BD rats

Le travail presente dans ce memoire concerne une etude du devenir d'un herbicide du mais, l'atrazine en condition de plein-champ: bilan et modes de dissipation. Des experimentations de laboratoire mettant en jeu des methodes diverses (suivi de l'atrazine #1#4c, couches minces et colonnes de terre, lysimetre non remanie) permettent d'etayer les resultats obtenus sur la parcelle experimentale du site observatoire des pollutions diffuses du lycee agricole de la cote saint andre (isere, france) ou a ete suivie pendant 3 ans la composition en herbicide et metabolites du sol sur 1 metre de profondeur et celle de l'eau interstitielle prelevee par bougies filtrantes. La matiere active (1 kg/ha) apportee annuellement fin avril se dissipe selon cinq voies d'importances tres inegales: volatilisation (15%), absorption par la culture (10%), adsorption sur le complexe argilo-humique et metabolisation (40-50%), entrainement vers les eaux profondes (30-40%). Dans la situation etudiee, les deux voies principales sont la metabolisation par la microflore du sol et l'entrainement lors des episodes pluvieux precoces. Apres un an de culture, la teneur en atrazine et derives au sein du premier metre de sol est voisine de 400 g/ha ce qui indique que l'evacuation de la matiere active n'est pas complete. Notre etude de terrain completee par une experimentation de laboratoire, conduit a mettre en evidence la possibilite de pertes precoces importantes de matiere active durant les deux premiers mois de culture. Trois concepts importants relatifs a l'efficacite d'un herbicide de prelevee emergent de notre etude: la concentration critique dans l'eau du sol, la duree critique durant laquelle cette concentration doit etre maintenue pour assurer l'effet herbicide, la profondeur critique qui represente la couche de sol dans laquelle doit jouer l'effet herbicide. Pour l'atrazine en culture de mais, dans nos conditions, ces criteres ont ete mesures: concentration critique: entre 50 et 200 micromoles ; duree critique: deux mois ; profondeur critique: 10 cm. Avec 1 kg/ha d'atrazine sous forme de suspension concentree, les trois criteres d'efficacite sont remplis malgre d'importantes pertes par drainage lors des episodes pluvieux precoces. Des modifications de formulation ayant pour consequence un relargage progressif devrait permettre l'economie d'une part importante de matiere active. La derniere partie de ce travail concerne une approche de mise en place de solutions alternatives de traitements herbicides en culture de mais

碩士<br>國立中央大學<br>遙測科技碩士學位學程<br>106<br>Aerosol optical depth (AOD) is one of the important indexes for air quality monitoring, in particular the time series. The new generation geostationary satellite, Himawari-8 (H-8), can provide 3 visible bands, 3 near infrared bands and 10 infrared bands with 0.5 km to 2 km spatial resolution every 10 minutes. The characteristics of multi-spectral bands and highly frequent observations are really suitable for the large scale air quality monitoring. For this purpose, Simultaneous Radiation Solution (SRS) is proposed to derive atmospheric transmittance and path radiance associated with the pre-constructed look-up-table (from Second Simulation of a Satellite Signal in the Satellite Spectrum model, 6S) for H-8 AOD and SSA (single scattering albedo) retrievals. In this study, Moderate Resolution Imaging Spectroradiometer (MODIS) products are employed to examine the practicality of SRS approach. The H-8 AOD retrievals show the similar pattern of spatial distribution with MODIS AOD products. However, the values compared to Aerosol Robotic Network (AERONET) observations are underestimated or overestimated, due to the uncertainties of H-8 surface reflectance database. Therefore, MODIS surface products are applied to H-8 AOD retrievals. Overall, the AOD spatial distribution and magnitudes are well consistent with MODIS product and AERONET observations. The relative error of AOD reduced from -43% to -4% when compared to the AERONET site at Chiayi station. Highly practical in retrieving AOD is suggested by the case study of MODIS. For time series air quality monitoring, the diurnal database of H-8 surface reflectance will be constructed based on MODIS products for highly temporal AOD observation in next step.

In film and still photography, depth of field control is often employed to control viewer interest in an image. This technique is also used in computer animation, but, in a medium where artists have near infinite control, must we rely on replicating photorealism? This research is a viable, non-photorealistic solution to the problem of directing viewer interest. Vision is directed by reducing superfluous visual information from parts of the image, which do not directly affect the depictive meaning of that image. This concept is applied to images and animations rendered from three-dimensional, computergenerated scenes, where detail is defined as visual information pertaining to the surface properties of a given object. A system is developed to demonstrate this concept. The system uses distance from a user-defined origin as the main mechanism to modulate detail. This solution is implemented within a modeling and shading environment to serve as a non-photorealistic, functional alternative for depth of field. This approach is conceptually based on a model of human vision, specifically, the relationship between foveal and peripheral vision, and is artistically driven by various works in the disciplines of painting and illustration, that through the careful manipulation of detail, control interest and understanding within the image. The resulting images and animations produced by this system provide viable evidence that detail modulation can be used to control effectively viewer interest in an image eliminating the need to use photographic techniques like depth of field.

碩士<br>逢甲大學<br>資訊工程所<br>90<br>Keeping safety is the primary goal for public utilities such as gas enterprise. In order to control pipeline network areas efficiently, necessary control over critical nodes is adopted by many public utilities. Using an optimal selection of such critical points, we can decide a closed area to be dominated when there is an accident happened. We found that current solutions providing control to pipeline network with a leakage of gas do not meet the optimal selection and simple needs to the public utility enterprises. On the contrary, these conventional works need a lot of related working experiences and background to complete such design goal. We derive a practical solution, an algorithm based on depth-first-search technique that is designed specifically to support the distinctive features of control point selection. With the determination of control points, we separate pipeline network into several components to dominate its flow supply efficiently and safely. The solution is designed to meet the following four high-level design goals: (1) low threshold to develop a new urban pipeline network system, (2) timely decision to leakage of flow in network, (3) low cost of network maintenance, and (4) compliance with enterprise security policies. A fundamental concept of our solution is the well-calculated weighted function which corresponds to hardware cost and customer cost. Another fundamental concept is the highly developed components that could be embedded in many applications. It is easily applied to any other public utility pipeline networks. We report the results of a trial that was carried out within a gas company and discuss how well the solution met our design goals.

This study investigated the causes of employee dissatisfaction by means of a case study of the Business Application Solution Centre (BASC) at the Eskom Academy of Learning (EAL). The rationale for the study was to contribute further to a general understanding of employee dissatisfaction. This study highlighted the issue of the under-representation of blacks and females (of all races) in senior positions, and further emphasised appointment and recruitment issues that promote unfair labour practices, organisational culture and structure issues that undermine workplace relations, and the extent to which management responds to the abovementioned issues. A mixed method approach was employed to gather data from BASC employees. Qualitative data was collected by means of one focus group discussion and nine in-depth, face-to-face interviews. For the focus group and face-to-face interviews, purposive sampling was used for the selection of respondents, in order to ensure representation on all race, gender and occupational strata. A semi-structured questionnaire was used for both the focus group and face-to-face interviews. The questioning route was guided by the themes of gender, appointment and recruitment issues, culture and structure issues, and management response and practice. Quantitative data was collected by means of an online survey. Even though the online survey link was sent to employees on all strata, top managers did not participate. The use of a web-based online survey had an element of immediacy and also ensured maximum confidentiality, as responses were transferred to a development server with no link or trace to the respondents. The study revealed many underlying causes of employee dissatisfaction, such as the following: (1) the main drivers of black and female under-representation in top positions were lack of skills development, mentoring and career-pathing; (2) among the recruitment and appointment practices leading to employee dissatisfaction was the appointment of employees to ‘acting’ rather than permanent management positions; (3) there was a perception that managers abused their authority by promoting their favourites and overlooking those who they did not like; (4) although an affirmative action (AA) policy had been implemented at BASC, it was felt that employees should be appointed and promoted on merit, and that this should be accompanied by mentoring; (5) in some instances, the hiring of consultants deprived employees of opportunities to perform critical tasks. The fact that consultants were paid more than employees was also a source of discontent; (6) appointment criteria were non-transparent, and respondents revealed that they knew who was going to be appointed even before the recruitment process had been completed; (7) a bureaucratic culture was found to be the main organisational culture issue undermining workplace relations. On the other hand, a culture of teamwork appeared to reduce dissatisfaction and enhance unity; (8) the major organisational structure issues undermining workplace relations were managers who lacked managerial competencies and unequal payment on the same grade; (9) employees who stood their ground were given a low rating during performance appraisals. Others were bullied by senior managers and colleagues, who were rude towards them; (10) a hostile working relationship between managers and employees was caused by managers who lacked human resource skills; and (11) junior managers were undermined by employees who bypassed them and went straight to senior managers to discuss workplace issues. This study addresses both the general lack of information regarding the causes of employee dissatisfaction in South Africa, and of employee dissatisfaction in the information and communication technology (ICT) workplace environment. The findings of the study will also contribute towards a better understanding of the general causes of employee dissatisfaction. The results of this study suggest that more in-depth investigations of the causes of employee dissatisfaction are necessary to fully address this issue, and in order to ultimately prevent a further increase in the rate of employee turnover. Some implications for further research became apparent during the course of this study: similar studies on employee dissatisfaction should be conducted with top managers; studies on the experience of managers appointed to acting positions should be undertaken; and follow-up studies on employee dissatisfaction should be conducted as causes are addressed and relevant interventions are implemented.<br>Business management<br>D.Litt. et Phil. (Sociology)

碩士<br>國立中興大學<br>園藝學系所<br>105<br>The Global warming is getting more and more severe in recent years, and it leads to abnormal climate and extreme weather conditions such as drought, heat wave, cold current and heavy rainfalls. The water resource is quite important in agronomic production process. The cultivation seasons of water bamboo in Taiwan are summer and autumn, if water shortage happens during these seasons, it will crash the industry. On the other hand, cultivating the water bamboo in short daylength will cause stunting disease, but previous research indicated that it can be overcome by extending the photoperiod. In this study, different cultivating water depths with or without photoperiod extension were applied to investigate the effects of water conservation and photoperiod extension on water bamboo (Zizania latifolia Turcz.) growth and development. Furthermore, we also investigated the effects of different light intensities on leaf senescence by using detached leaves and the effects of light intensities on water bamboo plant growth. In addition, it has been known that the smut fungi (Ustilago esculenta) which is parasitic on the water bamboo can produce the auxin in vivo. This study investigated the effects of Ustilago esculenta broth culture solution on squash seedling growth. Results from this research indicated that plant height, shoot length and shoot weight are positively correlated with cultivating water depth and photoperiod extension may increase water bamboo plant growth. Number of tillers per rhizome was affected by cultivating water depth, however, no significant difference was observed among the lower water depth treatments (8, 16, 24 cm), while significant differences did exist among the higher water depth treatments (30, 40, 50 cm).The number of tillers per rhizome with a cultivating water depth of 30 cm is greater than that of 50 cm. Furthermore, application of photoperiod extension to prevent stunting disease in early growth followed by growing with a cultivating water depth of 40 cm resulted in the best water bamboo quality. The results of water bamboo detached leaf experiment suggested that the reduction in leaf chlorophyll fluorescence and leaf chlorophyll content is effectively delayed under low light intensities (4, 7 PPFD). Because the light intensities applied in this experiment was much lower than that of the normal condition (2200 PPFD at sunny day noon) and the detached leaves were wounded, we conjectured that appropriate light intensity may effectively enhance leaf photosynthesis accumulate carbohydrates in leaves, and therefore postponed leaf senescence. Previous field experiments also indicated that light intensity can increase the water bamboo growth. Results from spraying or irrigating smut fungi (Ustilago esculenta) broth culture solution to squash seedlings suggested that plant height in all treatments is significantly higher than that of control and total growth increased about 80% at four weeks after treatment, interestingly, these results were not positively correlated with the concentrations of the solution. The node number of seedling were also promoted by treatment with the fungi broth culture solution with four more nodes in all treatments relative to the control. These results suggested that smut fungi broth culture solution may contain some growth promoting substance.

O suicídio é um ato complexo - difícil de compreender e aceitar -, em consequência do colapso das esperanças, planos e expectativas (pessoais, familiares e sociais). Embora a profissão de policial esteja ligada ao uso de força - e recorde-se que a polícia é a instituição legitimada pela sociedade para usar a força para a manutenção da ordem e os direitos individuais -, a ocorrência de mortes voluntárias, entre estes profissionais é significativa, considerando que esta é uma população testada, psicologicamente e fisicamente. Esta pesquisa, enquadrada na teoria das representações sociais, visa, essencialmente, analisar as perceções do suicídio entre os futuros policiais federais brasileiros - recrutas da Academia Nacional de Polícia - de ambos os sexos, com idades entre 21 e 49 anos de idade. Os dados foram recolhidos através de um questionário com dez perguntas - o presente estudo concentra-se em duas dessas perguntas, relacionadas com as razões para se tornar um policial, e com as representações de suicídio. As dimensões identificadas, após ACP, foram analisadas em função dos efeitos das variáveis independentes - sexo/género e grupo etário. O dinamismo e a autoridade são duas dimensões mais relevantes para os homens do que para as mulheres; elas estão mais preocupadas com alguns aspetos práticos - como ter um emprego estável e salário - do que os homens. Os resultados obtidos contribuem para entender alguns contextos em que podem ocorrer suicídios, alertando para a necessidade de uma melhor organização policial formal, para discutir as reais dimensões/problemas do seu trabalho quotidiano.<br>Suicide is often a complex response to the collapse of hopes, plans and expectations. It is always quite difficult to understand why it happens, being hard to face a death by suicide. Although the profession of police officer seems to be tied to the strength - and we must behold the police is the institution nowadays authorized by society to use force legitimately for the maintenance of order and individual rights - the occurrence of voluntary deaths among these professionals is significant, especially if we consider that this is a population psychologically and physically tested. This research, framed on the theory of social representations, aims, mainly, to analyze the perceptions of suicide among future Brazilian federal police - recruits at the National Police Academy - from both gender, with ages between 21 and 49 years old. The data was collected through a questionnaire with ten questions - the present study concentrates in two of those questions, related to the reasons to become a cop, and on the representations of suicide. The dimensions identified, after CPA, were analyzed according to the independent variables – sex/gender and age group. Dynamism and authority are dimensions more relevant to men than to women; in turn, they are more concerned with practical aspects - such as having a stable job and salary - than men. Our findings contribute to understand some contexts in which a suicide may occur, alerting to the necessity of formal police organization to discuss the real dimensions/problems of their quotidian work.

Exact analytical solutions for the quasistationary electromagnetic fields in the presence of conducting objects require the field solutions both internal and external to the conductors. Such solutions are limited for certain canonically shaped objects but are useful in testing the accuracy of various approximate models and numerical methods developed to solve complex problems related to real world conducting objects and in calibrating instruments designed to measure various field quantities. Theoretical investigations of quasistationary electromagnetic fields also aid in improving the understanding of the physical phenomena of electromagnetic induction. This thesis presents rigorous analytical expressions derived as benchmark solutions for the quasistationary field quantities both inside and outside, Joule losses and the electromagnetic forces acting upon a conducting spheroid placed in the proximity of a non-uniform field produced by current-carrying turns. These expressions are used to generate numerous numerical results of specified accuracy and selected results are presented in a normalized form for extended ranges of the spheroid axial ratio, the ratio of the depth of penetration to the semi-minor axis and the position of the inducing turns relative to the spheroids. They are intended to constitute reference data to be employed for comprehensive comparisons of results from approximate numerical methods or from boundary impedance models used for real world conductors. Approximate boundary conditions such as the simpler perfect electric conductor model or the Leontovich surface impedance boundary condition model can be used to obtain approximate solutions by only analyzing the field external to the conducting object. The range of validity of these impedance boundary condition models for the analysis of axisymmetric eddy-current problems is thoroughly investigated. While the simpler PEC model can be employed only when the electromagnetic depth of penetration is much smaller than the smallest local radius of curvature, the results obtained using the surface impedance boundary condition model for conducting prolate and oblate spheroids of various axial ratios are in good agreement with the exact results for skin depths of about 1/5 of the semi-minor axis when calculating electromagnetic forces and for skin depths less than 1/20 of the semi-minor axis when calculating Joule losses.

As nuclear energy grows in the United States and around the world, the expansion of the nuclear fuel cycle is inevitable. All currently deployed commercial reprocessing plants are based on the Plutonium - Uranium Extraction (PUREX) process. However, this process is not implemented in the U.S. for a variety of reasons, one being that it is considered by some as a proliferation risk. The 2001 Nuclear Energy Policy report recommended that the U.S. "develop reprocessing and treatment technologies that are cleaner, more efficient, less waste-intensive, and more proliferation-resistant." The Uranium Extraction (UREX+) reprocessing technique has been developed to reach these goals. However, in order for UREX+ to be considered for commercial implementation, a safeguards approach is needed to show that a commercially sized UREX+ facility can be safeguarded to current international standards. A detailed safeguards approach for a UREX+1a reprocessing facility has been developed. The approach includes the use of nuclear material accountancy (MA), containment and surveillance (C/S) and solution monitoring (SM). Facility information was developed for a hypothesized UREX+1a plant with a throughput of 1000 Metric Tons Heavy Metal (MTHM) per year. Safeguard goals and safeguard measures to be implemented were established. Diversion and acquisition pathways were considered; however, the analysis focuses mainly on diversion paths. The detection systems used in the design have the ability to provide near real-time measurement of special fissionable material in feed, process and product streams. Advanced front-end techniques for the quantification of fissile material in spent nuclear fuel were also considered. The economic and operator costs of these systems were not considered. The analysis shows that the implementation of these techniques result in significant improvements in the ability of the safeguards system to achieve the objective of timely detection of the diversion of a significant quantity of nuclear material from the UREX+1a reprocessing facility and to provide deterrence against such diversion by early detection.

At the northern extent of the Cascadia subduction zone, the subducting Explorer and Juan de Fuca plates interact across a translational deformation zone, known as the Nootka fault zone. The Seafloor Earthquake Array Japan-Canada Cascadia Experiment (SeaJade) was designed to study this region. In two parts (SeaJade I and II, deployed from July – September 2010 and January – September 2014), seismic data from the SeaJade project has led to several important discoveries. Hypocenter distributions from SeaJade I and II indicate primary and secondary conjugate faults within the Nootka fault zone. Converted phase analysis and jointly determined seismic tomography with double-difference relocated hypocenters provide evidence to several velocity-contrasting interfaces seaward of the Cascadia subduction front at depths of ~4-6 km, ~6-9 km, ~11-14 km, and ~14-18 km, which have been interpreted as the top of the oceanic crust, upper/lower crust boundary, oceanic Moho, and the base of the highly fractured and seawater/mineral enriched veins within oceanic mantle. During SeaJade II, a MW 6.4 mainshock and subsequent aftershocks, known as the Nootka Sequence, highlighted a previously unidentified fault within the subducted Explorer plate. This fault reflects the geometry of the subducting plate, showing downward bending of the plate toward the northwest. This plate bend can be attributed to negative buoyancy from margin parallel mantle flow induced by intraslab tearing further northwest. Seismic tomography reinforces the conclusions drawn from the Nootka Sequence hypocenter distribution. Earthquakes from the entire SeaJade II catalogue reveal possible rotated paleo-faults, identifying the former extent of the Nootka fault zone from ~3.5 Ma.<br>Graduate

The utilization of in vitro tests with a tiered testing strategy for detection of mild ocular irritants can reduce the use of animals for testing, provide mechanistic data on toxic effects, and reduce the uncertainty associated with dose selection for clinical trials. The first section of this thesis describes how in vitro methods can be used to improve the prediction of the toxicity of chemicals and ophthalmic products. The proper utilization of in vitro methods can accurately predict toxic threshold levels and reduce animal use in product development. Sections two, three and four describe the development of new sensitive in vitro methods for predicting ocular toxicity. Maintaining the barrier function of the cornea is critical for the prevention of the penetration of infections microorganisms and irritating chemicals into the eye. Chapter 2 describes the development of a method for assessing the effects of chemicals on tight junctions using a human corneal epithelial and canine kidney epithelial cell line. In Chapter 3 a method that uses a primary organ culture for assessing single instillation and multiple instillation toxic effects is described. The ScanTox system was shown to be an ideal system to monitor the toxic effects over time as multiple readings can be taken of treated bovine lenses using the nondestructive method of assessing for the lens optical quality. Confirmations of toxic effects were made with the utilization of the viability dye alamarBlue. Chapter 4 describes the development of sensitive in vitro assays for detecting ocular toxicity by measuring the effects of chemicals on the mitochondrial integrity of bovine cornea, bovine lens epithelium and corneal epithelial cells, using fluorescent dyes. The goal of this research was to develop an in vitro test battery that can be used to accurately predict the ocular toxicity of new chemicals and ophthalmic formulations. By comparing the toxicity seen in vivo animals and humans with the toxicity response in these new in vitro methods, it was demonstrated that these in vitro methods can be utilized in a tiered testing strategy in the development of new chemicals and ophthalmic formulations.