Esta pesquisa apresenta um estudo de uma argamassa modificada para uso como elemento de ligação entre elementos de concreto pré-moldado. A argamassa utilizada nesta pesquisa é obtida pela introdução de látex estireno-butadieno (SB) e fibras de polipropileno a uma argamassa de cimento e areia. Estas adições modificam suas propriedades mecânicas, proporcionando o aumento da deformabilidade por diminuição do módulo de elasticidade do compósito, conferindo-lhe características favoráveis ao uso como elemento de apoio para elementos pré-moldados de concreto. Foram realizados ensaios de caracterização do compósito por meio da obtenção das resistências à compressão e à tração e, do módulo de elasticidade para corpos-de-prova cilíndricos com 50 mm de diâmetro com 100 mm de altura. Ensaios de capacidade de deformação, capacidade de rotação e capacidade de acomodação de imperfeições e distribuição das tensões foram realizados em almofadas de 150 mm x 150 mm com espessura de 10 mm. Os resultados mostraram que o material possui boa capacidade de se deformar em níveis de tensão da ordem de 10 a 20 MPa mantendo sua resiliência. Valores de rotações entre 0,01 e 0,02 rad foram obtidos nos ensaios, sendo estas maiores que os valores necessários para a maioria dos casos convencionais de projeto. Na acomodação e distribuição das tensões, a presença das almofadas promoveu uma melhora de 25% no desempenho de ligações submetidas à compressão uniforme, com rugosidades de 1,0 mm. / This research presents a study of a mortar modified to use as bearing pad between precast concrete elements. The mortar used in this research is achieved by the introduction of styrene-butadiene latex (SB) and polypropylene fibers into a cement mortar and sand, modifying their mechanical properties, as increase of the potential deformation by decrease of the composite modulus of elasticity, providing favorable characteristics to the use as bearing pad for precast concrete elements. Cylindrical samples of 50 mm of diameter with height of 100 mm were molded and tested to determination the compressive and the tensile strength and also the modulus of elasticity of the composite. Compression tests with cushions of 150 mm x 150 mm of base with thickness of 10 mm were done to determinate the deformation capacity, rotation capacity and capacity of accommodation of imperfections and distribution of the stresses between precast elements. The results showed that the material has a capacity to deform in levels of tension from 10 to 20 MPa maintaining his resilience. Values of rotations among 0,01 and 0,02 rad were obtained, being these larger ones than the necessary values for most of the conventional cases of project. In the accommodation and distribution of the stresses, the presence of the bearing pad promoted an improvement of 25% in the strength of connections subject to uniform compressive stresses, with surface irregularities of 1,0 mm.

L’Artériopathie Oblitérante des Membres Inférieurs (AOMI) est une pathologie chronique grave, induite par le processus physiopathologique d’athérosclérose. Diagnostiquée par la mesure de l’Index de Pression Systolique (IPS) de repos cette pathologie se traduit chez la plupart des patients par une ischémie (apports sanguins insuffisants) à l’exercice pouvant causer l’apparition de douleurs au niveau des membres inférieurs lors de la marche. Le premier axe de travail de cette thèse visait à évaluer la pertinence pédagogique des méthodes actuelles d’enseignement de l’IPS dans les facultés de médecine françaises. Les résultats des premiers travaux de recherche qui ont été menés montrent que les méthodes actuelles ne permettent pas aux étudiants de maîtriser les fondamentaux de cette mesure diagnostique. D’autres travaux ont alors été menés afin de définir la place et la forme que devrait prendre l’enseignement de l’IPS dans le cursus médical afin qu’il puisse être acquis par les futurs médecins de manière fiable et durable. Le second axe de travail de cette thèse visait à proposer une nouvelle approche méthodologique basée sur l’utilisation conjointe de deux moniteurs portables (accéléromètre et montre marqueur d’événements) permettant la quantification des douleurs ischémiques à l’exercice des patients atteints d’AOMI en condition de vie réelle. Les résultats issus de ces travaux ouvrent des perspectives nouvelles pour le chercheur ou le clinicien pour la compréhension des limitations fonctionnelles des patients atteints d’AOMI dans leur contexte de vie. / Lower-extremity Peripheral Artery Disease (PAD) is a severe non-communicable disease that is associated with atherosclerosis. Diagnosed by Ankle- Brachial Index (ABI), PAD leads, in most patients, to ischemia (mismatch between blood demand and blood supply) during exercise that may lead to the occurrence of pain in the lower extremities during walking. The first axis of the present thesis was to assess the level of knowledge on this diagnostic tool among French medical students. Our results suggest that the way of teaching or learning the ABI procedure is deficient. According to these results we conducted another study to determine the best teaching method to improve students’ ABI proficiency. The second axis of the present thesis was to proposed a new method using wearable monitors (accelerometer and Micro Motion logger watch) to objectively identify and quantify lower limb walking pain manifestation as well as stop induced by walking pain during daily life in PAD patients. Our results can provide researchers and clinicians with a more realistic and holistic view of the functional limitations of PAD patients in free-living conditions.

I denna kandidatuppsats avlägsnas organiska föroreningar från vatten genom användning av textilier, vars yta belagts med nanopartiklar utav ämnet titandioxid. När titandioxid belyses med UV-strålning sker en fotokatalytisk reaktion, vilket i sin tur bryter ned bland annat bakterier och organiska färgämnen. I hopp om att finna ultimat vidhäftning mot textil passande titandioxid har olika typer av beläggningar studerats; akrylbaserade, sol-gel och slutligen en hybrid. Dessutom har fem olika konstruktioner av textila bindningar jämförts i syfte att undersöka dess påverkan på den fotokatalytiska effekten. Förorenade vatten är ett stort problem, både i utvecklingsländer och i industriella sammanhang. Att använda en textil fr att rena nedsmutsat vatten är en lockande tanke, speciellt attraktivt är förmågan att dra nytta av endast solenergi. En av fördelarna med textilier inom området är möjligheten att tillverka stora tygareor på ett enkelt och kostnadseffektivt vis.Elementär analys visade att TiO2-partikellager på textilierna fastande i olika grad beroende på beläggningsteknik. Avfärgning genom nedbrytning av metylenblått studerades under sollampa. Proverna utvärderades genom att vid bestämda tidpunkter avläsa kromavärdet på färglösningen. För att erhålla mer information om textilernas effekt gjordes även en bakterieanalys, samt bildtagning i ytterlig förstorning med SEM. Resultaten visade goda fotokatalytiska egenskaper för samtliga beläggningar, däribland är akryl- och hybridbeläggningarna mest lovande. Utöver det visade de textila bindningarna på substratens konstruktioner ha en påverkan på den vattenrenande effekten.In this bachelor essay work organic contaminants are removed from water using textiles, whose surface is coated with nanoparticles of titanium dioxide. When titanium dioxide is illuminated with UV radiation a photocatalytic reaction occurs, which in turn degrades substances such as bacteria and organic dyes. In hope of finding the ultimate adhesion for a textile coating suitable with titanium dioxide, various types of coatings are studies; acrylicbased, sol-gel and finally a hybrid coating. In addition, five different structures of textiles are compared in order to examine their different outcome in photocatalytic effect.Contaminated water is a major problem in both developing countries and industrial context. The use of a fabric to purify polluted water is an attractive idea, especially because the ability to exploit only solar energy. One of the benefits with use of fabric is the ability to producelarge areas of fabric, a process which is both simple and costeffective.Elemental analyses showed varying degree of fasten of the particle layer of TiO2 depending on the coating technology used. Decolorization by degradation of methylene blue was studied under a solar energy AM 1,5 lamp. The samples were evaluated by reading the chroma value of the color solution at specified moments. To obtain more information the coated textiles went through bacterial analysis, as well as picture shooting in extreme magnification with SEM. The results showed good photocatalytic properties for all coatings, among them were the acrylic coating and the hybrid most promising. In addition, results showed that depending on textile structures different effects in water purification was achieved. / Program: Textilingenjörsutbildningen

Previous investigators demonstrated that epididymal white adipose tissue (EWAT) lipectomy suppressed spermatogenesis and caused atrophy of the seminiferous tubules. EWAT lipectomy, however, may disrupt testicular innervation, which reportedly compromises testicular function. To resolve this confound and better clarify the role of EWAT in spermatogenesis, three experimental groups of hamsters were created in which: i.) the superior and inferior spermatic nerves were transected (SSNx) at the testicular level, ii.) EWAT was extirpated (EWATx), and iii.) testicular nerves and EWAT were left intact (SHAM controls). It was hypothesized that transection of the superior and inferior spermatic nerves would disrupt normal spermatogenesis. The findings indicate a significant reduction in spermatogenic activity and marked seminal tubule atrophy within the EWATx testis, as compared to the SSNx and controls testes, which did not differ significantly from each other. From these data, it is concluded that EWAT, and not testicular innervation, is central to normal spermatogenesis.

Variability has become one of the vital challenges that the designers of integrated circuits encounter. variability becomes increasingly important. Imperfect manufacturing process manifest itself as variations in the design parameters. These variations and those in the operating environment of VLSI circuits result in unexpected changes in the timing, power, and reliability of the circuits. With scaling transistor dimensions, process and environmental variations become significantly important in the modern VLSI design. A smaller feature size means that the physical characteristics of a device are more prone to these unaccounted-for changes. To achieve a robust design, the random and systematic fluctuations in the manufacturing process and the variations in the environmental parameters should be analyzed and the impact on the parametric yield should be addressed. This thesis studies the challenges and comprises solutions for designing robust VLSI systems in the presence of variations. Initially, to get some insight into the system design under variability, the parametric yield is examined for a small circuit. Understanding the impact of variations on the yield at the circuit level is vital to accurately estimate and optimize the yield at the system granularity. Motivated by the observations and results, found at the circuit level, statistical analyses are performed, and solutions are proposed, at the system level of abstraction, to reduce the impact of the variations and increase the parametric yield. At the circuit level, the impact of the supply and threshold voltage variations on the parametric yield is discussed. Here, a design centering methodology is proposed to maximize the parametric yield and optimize the power-performance trade-off under variations. In addition, the scaling trend in the yield loss is studied. Also, some considerations for design centering in the current and future CMOS technologies are explored. The investigation, at the circuit level, suggests that the operating temperature significantly affects the parametric yield. In addition, the yield is very sensitive to the magnitude of the variations in supply and threshold voltage. Therefore, the spatial variations in process and environmental variations make it necessary to analyze the yield at a higher granularity. Here, temperature and voltage variations are mapped across the chip to accurately estimate the yield loss at the system level. At the system level, initially the impact of process-induced temperature variations on the power grid design is analyzed. Also, an efficient verification method is provided that ensures the robustness of the power grid in the presence of variations. Then, a statistical analysis of the timing yield is conducted, by taking into account both the process and environmental variations. By considering the statistical profile of the temperature and supply voltage, the process variations are mapped to the delay variations across a die. This ensures an accurate estimation of the timing yield. In addition, a method is proposed to accurately estimate the power yield considering process-induced temperature and supply voltage variations. This helps check the robustness of the circuits early in the design process. Lastly, design solutions are presented to reduce the power consumption and increase the timing yield under the variations. In the first solution, a guideline for floorplaning optimization in the presence of temperature variations is offered. Non-uniformity in the thermal profiles of integrated circuits is an issue that impacts the parametric yield and threatens chip reliability. Therefore, the correlation between the total power consumption and the temperature variations across a chip is examined. As a result, floorplanning guidelines are proposed that uses the correlation to efficiently optimize the chip's total power and takes into account the thermal uniformity. The second design solution provides an optimization methodology for assigning the power supply pads across the chip for maximizing the timing yield. A mixed-integer nonlinear programming (MINLP) optimization problem, subject to voltage drop and current constraint, is efficiently solved to find the optimum number and location of the pads.

Les travaux réalisés dans cette thèse proposent une aide à la décision pour améliorer la qualité de l'apprentissage. L'apprentissage scolaire englobe deux dimension; une dimension humaine et une dimension pédagogique. La dimension humaine inclut l'apprenant et l'enseignant. La dimension pédagogique, représentée par le programme fixé par l'établissement éducatif, correspond au savoir. Ce dernier va se transformer en connaissance chez l'apprenant. Les deux notions de connaissance et savoir sont donc tout à fait différentes. La distance entre les deux représente la distance entre ce que l'enseignant présente (le savoir) et ce que l'apprenant acquière (la connaissance). La qualité de l'apprentissage concerne les apprenants qui vont à l'école pour acquérir le savoir. En fait, apprendre consiste à intérioriser le savoir. Cette intériorisation demande des efforts pour un changement intellectuel persévérant et exige une continuité basée sur les expériences antérieures. L'acquisition du savoir et sa transformation en connaissance par l'apprenant sont influencées par plusieurs facteurs qui interviennent positivement ou négativement sur la quantité et la qualité de cette connaissance. Il peut résider chez l'apprenant une confusion entre les deux notions qui peut l'amener à valoriser ou ignorer sa connaissance. Le processus de construction des connaissances par le savoir diffusé exige une constante mise en œuvre de procédures d'évaluation. Le processus d'évaluation apprécie alors la structure de la connaissance pour prendre des décisions destinées à la faire évoluer. Cependant, lors d'une évaluation, la confusion entre connaissance et savoir peut amener l'apprenant à valoriser le score, négligeant ainsi le regard qu'il pourrait porter sur les processus de transformation des connaissances au profit d'une restitution la plus fidèle possible du savoir. Cette confusion peut être mise en évidence pourvu que l'évaluation intègre une dimension processuelle. Dès lors, l'évaluation peut être mieux associée à des actions d'amélioration et de transformation des connaissances. L'évaluation peut alors être abordée dans une logique d'aide à la décision. Dans ce travail nous montrerons donc qu'une situation d'apprentissage s'apparente à une situation d'aide à la décision.

Multipath amplifier theory: In this thesis it is proven that the theoretical minimum noise measure of a multipath amplifier (an amplifier which has multiple parallel amplifiers) is achieved by using the optimum source impedance for the amplifier and the optimum gain for each amplification path. This optimum source impedance and gain can be calculated by using the optimum–loaded input network, i.e. by replacing each amplifier with its optimum source impedance. The resulting noise measure is the same as the minimum noise measure of the amplifiers used in the amplification paths. Whereas single–path amplifiers can achieve this minimum noise measure over narrow bandwidths, multipath amplifiers are theoretically able to achieve the minimum noise measure over very broad bandwidths. The theory is demonstrated by applying it to distributed amplifiers. In an ideal distributed amplifier, the magnitude of the optimum gain of the amplification paths decreases and the phase delay increases the farther the stage is from the input, with the decrease in gain being faster for higher frequencies. The challenge in designing broadband, low–noise, distributed amplifiers is to achieve optimum gain matching over broad bandwidths. Multipath amplifier design procedure: Based on the theory, a three step design and optimisation procedure is introduced. Firstly, unconditionally stable amplification paths are designed to have small minimum noise measures, then an input network is designed for optimum source impedance matching and lastly an output network is designed for gain matching. Multipath amplifier prototype: The theory and design procedure is demonstrated by optimising a 0.5–2 GHz distributed amplifier. An average noise measure of 0.3 dB is achieved, which is only 0.1 dB higher than the minimum noise measure of the amplification stages used. This increase is mainly due to transmission line loss and gain mismatch. Radio telescope feasibility: Multipath amplifiers break the trade–off between noise temperature, bandwidth and source termination that a single–path amplifier has, because they have much more design freedom when designing the input network. In general, the more paths, the larger the low–noise bandwidth, but the larger and more complex the amplifier. Roughly two to three amplification paths are required per octave of bandwidth for LNAs around 1 GHz. When the bandwidth is very narrow, a single path is sufficient. Multipath amplifiers have similar trade–offs between linearity and power consumption, between noise temperature and noise resistance, and between noise temperature and size to a single–path amplifier. Multipath amplifiers are therefore a feasible alternative for use in radio telescopes. / Thesis (Ph.D. (Space Physics))--North-West University, Potchefstroom Campus, 2011.

Multipath amplifier theory: In this thesis it is proven that the theoretical minimum noise measure of a multipath amplifier (an amplifier which has multiple parallel amplifiers) is achieved by using the optimum source impedance for the amplifier and the optimum gain for each amplification path. This optimum source impedance and gain can be calculated by using the optimum–loaded input network, i.e. by replacing each amplifier with its optimum source impedance. The resulting noise measure is the same as the minimum noise measure of the amplifiers used in the amplification paths. Whereas single–path amplifiers can achieve this minimum noise measure over narrow bandwidths, multipath amplifiers are theoretically able to achieve the minimum noise measure over very broad bandwidths. The theory is demonstrated by applying it to distributed amplifiers. In an ideal distributed amplifier, the magnitude of the optimum gain of the amplification paths decreases and the phase delay increases the farther the stage is from the input, with the decrease in gain being faster for higher frequencies. The challenge in designing broadband, low–noise, distributed amplifiers is to achieve optimum gain matching over broad bandwidths. Multipath amplifier design procedure: Based on the theory, a three step design and optimisation procedure is introduced. Firstly, unconditionally stable amplification paths are designed to have small minimum noise measures, then an input network is designed for optimum source impedance matching and lastly an output network is designed for gain matching. Multipath amplifier prototype: The theory and design procedure is demonstrated by optimising a 0.5–2 GHz distributed amplifier. An average noise measure of 0.3 dB is achieved, which is only 0.1 dB higher than the minimum noise measure of the amplification stages used. This increase is mainly due to transmission line loss and gain mismatch. Radio telescope feasibility: Multipath amplifiers break the trade–off between noise temperature, bandwidth and source termination that a single–path amplifier has, because they have much more design freedom when designing the input network. In general, the more paths, the larger the low–noise bandwidth, but the larger and more complex the amplifier. Roughly two to three amplification paths are required per octave of bandwidth for LNAs around 1 GHz. When the bandwidth is very narrow, a single path is sufficient. Multipath amplifiers have similar trade–offs between linearity and power consumption, between noise temperature and noise resistance, and between noise temperature and size to a single–path amplifier. Multipath amplifiers are therefore a feasible alternative for use in radio telescopes. / Thesis (Ph.D. (Space Physics))--North-West University, Potchefstroom Campus, 2011.

Variability has become one of the vital challenges that the designers of integrated circuits encounter. variability becomes increasingly important. Imperfect manufacturing process manifest itself as variations in the design parameters. These variations and those in the operating environment of VLSI circuits result in unexpected changes in the timing, power, and reliability of the circuits. With scaling transistor dimensions, process and environmental variations become significantly important in the modern VLSI design. A smaller feature size means that the physical characteristics of a device are more prone to these unaccounted-for changes. To achieve a robust design, the random and systematic fluctuations in the manufacturing process and the variations in the environmental parameters should be analyzed and the impact on the parametric yield should be addressed. This thesis studies the challenges and comprises solutions for designing robust VLSI systems in the presence of variations. Initially, to get some insight into the system design under variability, the parametric yield is examined for a small circuit. Understanding the impact of variations on the yield at the circuit level is vital to accurately estimate and optimize the yield at the system granularity. Motivated by the observations and results, found at the circuit level, statistical analyses are performed, and solutions are proposed, at the system level of abstraction, to reduce the impact of the variations and increase the parametric yield. At the circuit level, the impact of the supply and threshold voltage variations on the parametric yield is discussed. Here, a design centering methodology is proposed to maximize the parametric yield and optimize the power-performance trade-off under variations. In addition, the scaling trend in the yield loss is studied. Also, some considerations for design centering in the current and future CMOS technologies are explored. The investigation, at the circuit level, suggests that the operating temperature significantly affects the parametric yield. In addition, the yield is very sensitive to the magnitude of the variations in supply and threshold voltage. Therefore, the spatial variations in process and environmental variations make it necessary to analyze the yield at a higher granularity. Here, temperature and voltage variations are mapped across the chip to accurately estimate the yield loss at the system level. At the system level, initially the impact of process-induced temperature variations on the power grid design is analyzed. Also, an efficient verification method is provided that ensures the robustness of the power grid in the presence of variations. Then, a statistical analysis of the timing yield is conducted, by taking into account both the process and environmental variations. By considering the statistical profile of the temperature and supply voltage, the process variations are mapped to the delay variations across a die. This ensures an accurate estimation of the timing yield. In addition, a method is proposed to accurately estimate the power yield considering process-induced temperature and supply voltage variations. This helps check the robustness of the circuits early in the design process. Lastly, design solutions are presented to reduce the power consumption and increase the timing yield under the variations. In the first solution, a guideline for floorplaning optimization in the presence of temperature variations is offered. Non-uniformity in the thermal profiles of integrated circuits is an issue that impacts the parametric yield and threatens chip reliability. Therefore, the correlation between the total power consumption and the temperature variations across a chip is examined. As a result, floorplanning guidelines are proposed that uses the correlation to efficiently optimize the chip's total power and takes into account the thermal uniformity. The second design solution provides an optimization methodology for assigning the power supply pads across the chip for maximizing the timing yield. A mixed-integer nonlinear programming (MINLP) optimization problem, subject to voltage drop and current constraint, is efficiently solved to find the optimum number and location of the pads.

BACKGROUND: Osteoarthritis is a leading cause of disability in people of 65 and older. Researches have shown several possible factors leading to knee osteoarthritis development. Patellofemoral joint maltracking has been thought to be associated with or caused edema in the knee; which is thought to be the early signs of osteoarthritis. Hoffa's fat pad is an intra-articular component of knee located under the kneecap. It has also been suggested as one marker for osteoarthritis, when MRI shows a presence of edema in it. Recently, edema in the superolateral region of Hoffa's fat pad has been hypothesized as a distinct signal than the edema on other regions. There is an interest in finding the relation of this superolateral edema with other factors of osteoarthritis development. OBJECTIVE: This thesis research project is aimed to assess the relation of kneecap-thighbone (patellofemoral) joint alignment, femoral trochlea morphology, and patellar height to edema in the superolateral region of Hoffa’s fat pad especially in the population with average age above 65 years old. The hypothesis is that the flatter trochlear morphology and abnormal patella alignment will have higher risk of superolateral edema. METHODS: This is a cross-sectional study using a subset data from Multicenter Osteoarthritis (MOST) study, specifically at 60-month visit. This study measured the patellofemoral measurements (sulcus angle, lateral and medial trochlear inclination angle, trochlear angle, Insall-Salvati ratio, patellar tilt angle, and bisect offset) as the predictor variables, and semiquantitative scoring of MRI edema in superolateral Hoffa’s fat pad as the outcome variable. Logistic regression analyses were performed to find the strongly associated patellofemoral measurements to superolateral Hoffa’s fat pad edema. RESULTS: From the logistic regression analysis, trochlear angle, Insall-Salvati ratio, and bisect offset were highly associated with the superolateral edema. A further analysis, by categorizing the measurements to quartiles, was found that only the highest quartiles of both bisect offset and trochlear angle are associated with superolateral Hoffa’s fat pad edema when compared to the reference quartile. All quartiles of Insall-Salvati ratio are strongly associated with superolateral edema when compared to the reference quartile. CONCLUSION: Current study presents that people above 65 years old with high trochlear angle, extreme lateral patellar translation or bisect offset, and high patella riding have high risk of having superolateral Hoffa’s fat pad edema.