Dissertations / Theses on the topic '68W40'

Cette thèse est composée de deux parties. La première concerne les échantillonneurs dits de Monte-Carlo séquentiel (les échantillonneurs SMC). Il s'agit d'une famille d'algorithmes pour produire des échantillons venant d'une suite de distributions, grâce à une combinaison de l'échantillonnage pondéré et la méthode de Monte-Carlo par chaîne de Markov (MCMC). Nous proposons une version améliorée qui exploite les particules intermédiaires engendrées par l'application de plusieurs pas de MCMC. Elle a une meilleure performance, est plus robuste et permet la construction d'estimateurs de la variance. La deuxième partie analyse des algorithmes de lissage existants et en propose des nouveaux pour les modèles espace-état. Le lissage étant coûteux en temps de calcul, l'échantillonnage par rejet a été proposé dans la littérature comme une solution. Cependant, nous démontrons que son temps d'exécution est très variable. Nous développons des algorithmes ayant des coûts de calcul plus stables et ainsi plus adaptés aux architectures parallèles. Notre cadre peut aussi traiter des modèles dont la densité de transition n'est pas calculable<br>This thesis is composed of two parts. The first part focuses on Sequential Monte Carlo samplers, a family of algorithms to sample from a sequence of distributions using a combination of importance sampling and Markov chain Monte Carlo (MCMC). We propose an improved version of these samplers which exploits intermediate particles created by the application of multiple MCMC steps. The resulting algorithm has a better performance, is more robust and comes with variance estimators. The second part analyses existing and develops new smoothing algorithms in the context of state space models. Smoothing is a computationally intensive task. While rejection sampling has been proposed as a solution, we prove that it has a highly variable execution time. We develop algorithms which have a more stable computational cost and thus are more suitable for parallel environments. We also extend our framework to handle models with intractable transition densities

Many large carnivores are declining globally; most threatened or risk extinction due to a loss of habitat, resources, and direct removal; often the later as a result of conflict with humans. Although leopards and many meso-carnivore species are still free roaming in South Africa, few data are available on these species outside large protected areas as they are often elusive, wide ranging and found at low densities. More data are needed on the population dynamics, ecology and biology of species such as leopard, if we are to implement evidence-based approaches to their conservation within small reserves and surrounding unprotected areas. Camera traps are being increasingly utilized in research, as they can record data on a species or a whole community at relatively low cost. Here we used a network of camera traps to monitor species presence at Thaba Tholo Wilderness Reserve, Mpumalanga, South Africa. We found that camera trap efficacy varied between species, with smaller carnivores significantly under-recorded more frequently than larger predators. However, leopards were successfully captured by camera trap when compared with more traditional monitoring methods (i.e. spoor). Small reserves may play an important role in the conservation of carnivores, but often these reserves are surrounded by farmland and the successful separation of livestock and game using a fence can affect vegetation composition, fragmenting the land further. However, these effects may be limited by the free movement of wild browsers and grazers through holes in the fence which may also decrease the negative effects of fencing while supporting endangered and highly mobile species such as the leopard Panthera pardus. Leopard densities were found to be 3.04 (S.E. +/-1.55) to 4.97 (S.E. +/-2.14) leopards per 100km2, which was lower than other estimates from South Africa, however the population was stable throughout the study suggesting the reserve was a source for leopard and offspring were dispersing. Although there was no evidence of habitat preference by the leopard, habitat was found to be more significant in influencing relative local abundances of meso-carnivores than potential associations with leopard and other larger carnivores. However abundance may have been affected by factors outside the reserve as conflict with humans was evident. Negative actions towards leopard and other carnivores in retaliation to the predation of animal stock occurred in the farmland surrounding the study site, with a significantly higher percentage of commercial game farmers responding that they would take action against one or more species of carnivore compared to livestock owners. The financial loss sustained with increasing game prices in South Africa could therefore increase the conflict between humans and carnivores across the country, which in turn could have detrimental effects on local leopard and other carnivore populations. The relatively high numbers of the extremely rare erythristic leopard occurring within the relatively low density leopard population is likely to be the result of genetic drift, which may have been a result of this conflict; highlighting that although small reserves may play an important role in the protection and propagation of threatened species it is human acceptance of carnivores which is likely to be vital in the successful conservation and long term survival of predators outside protected areas.

This thesis examines the life and ministry of William Van Mildert (I765-I836) and his membership of the early nineteenth century High Church group known as the Hackney Phalanx. It considers Van Mildert's experiences before ordination and as deacon, priest and bishop, and their influence on his conception of the nature and mission of the Church of England. It relates the measures initiated by the Phalanx for reforming and extending the work of the Church to its members' understanding of their social and political context, and indicates some features of their shared theological position, particularly their ecclesiology. Among the undertakings of the Phalanx, the restructuring of the S.P.C.K, and the founding of new Church Societies to promote education and church-building receive particular attention. Van Mildert's labours as a member of the House of Lords are considered in detail, especially during his Durham episcopate (1826-36), when he was prominent in the unsuccessful opposition to Roman Catholic emancipation and to the Church Temporalities (Ireland) Act of 1833.The founding of Durham University owed much to Van Mildert, Besides contributing an estimated £10,000, he was closely involved both in developing the plans and in piloting the necessary legislation through Parliament. Van Mildert's theological writings are more notable for their extensive acquaintance with the work of earlier theologians than for originality: he disliked Innovation in matters of religion. Besides sermons and episcopal charges, he published Boyle Lectures taking a systematic view of the rise and progress of Infidelity and (while Oxford Regius Professor of Divinity) Bampton Lectures on the principles of Scripture-interpretation. He also produced a complete edition of the works of Waterland. Cited as a theological authority by the Oxford Movement, he nevertheless held aloof from the Movement’s beginnings.

Background: Previous research has identified that the occurrence of a Global Tonic Clonic Seizure (GTCS) is a high risk factor for serious injury or death within the epilepsy population. Fast intervention during a GTCS accompanied by EEG suppression is needed to reduce the risk of serious injury or death. Research has suggested that intervention should optimally occur within 50 seconds of EEG suppression commencing. Identifying patients who are at greatest risk of GTCS could enable targeted monitoring of patients and facilitate quicker intervention. However, at this time there are no specific guidelines for risk assessment in regards to risk of GTCS. The William Quarrier’s Scottish Epilepsy Centre (SEC) developed a Seizure Assessment Risk Score (SARS) tool for use in Video Telemetry (VT) epilepsy units based on risk factors highlighted by previous research. The SARS was implemented with all new admissions to the SEC and data was collected on seizure activity through routine clinical practice. Aim: The aim of this study was to investigate the efficacy of the SARS tool at predicting the occurrence of GTCS activity in patients admitted to the SEC. Methods: Seizure activity data and daily SARS scores were collected from 37 patients admitted to the SEC over an 8 month period. The data were then explored to determine if there was a predictive relationship between higher SARS scores and GTCS occurrence. Results: Data from 37 patients indicated that there was no significant relationship between higher scores on the SARS and the incidence of GTCS. The current SARS tool does not appear to adequately differentiate between those patients who do experience a GTCS during their admission to the VT unit and those who do not. Conclusion: The study highlights that the SARS tool requires further development to ensure that patients are adequately assessed for risk of experiencing a GTCS. While the majority of the sample was rated ‘high risk’ according to the SARS tool, the incidence of GTCS was in fact relatively low. The study also discusses the difficulties surrounding risk assessing an already specialised and clinically risky population.

Alexithymia refers to difficulties in recognizing one’s own emotions and others emotions. Theories of emotional embodiment suggest that, in order to understand other peoples’ feelings, observers re-experience, or simulate, the relevant component (i.e. somatic, motor, visceral) of emotion’s expressed by others in one’s self. In this way, the emotions are “embodied”. Critically, to date, there are no studies investigating the ability of alexithymic individuals in embodying the emotions conveyed by faces. In the present dissertation different implicit paradigms and techniques falling within the field of affective neuroscience have been employed in order to test a possible deficit in the embodiment of emotions in alexithymia while subjects were requested to observe faces manifesting different expression: fear, disgust, happiness and neutral. The level of the perceptual encoding of emotional faces and the embodiment of emotions in the somato-sensory and sensory-motor system have been investigated. Moreover, non-communicative motor reaction to emotional stimuli (i.e. visceral reactions) and interoceptive abilities of alexithymic subjects have been explored. The present dissertation provided convergent evidences in support of a deficit in the processing of fearful expression in subjects with high alexithymic personality traits. Indeed, the pattern of fear induced changes in the perceptual encoding, in the somato-sensory and in the somato-motor system (both the communicative and non communicative one) is widely and consistently altered in alexithymia. This support the hypothesis of a diminished responses to fearful stimuli in alexithymia. In addition, the overall results on happiness and disgust, although preliminary, provided interesting results. Indeed, the results on happiness revealed a defective perceptual encoding, coupled with a slight difficulty (i.e. delayed responses) at the level of the communicative somato-motor system, and the emotion of disgust has been found to be abnormally embodied at the level of the somato-sensory system.

Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1990.<br>Title as it appears in the M.I.T. Graduate List, June 1990: Asian American professionals in the Massachusetts high technology industry.<br>Includes bibliographical references (leaves 54-56).<br>by Shirley Mark.<br>M.C.P.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2011.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 253-270).<br>Environmental Justice (EJ) scholarship has revealed that communities of color and low-income neighborhoods have been disproportionally affected by 'brown' contaminating facilities and excluded from decision-making on their land, and that residents have used a variety of strategies to address such injustices (Bullard 1990, Agyeman 2003, Susskind and Macey 2004, Corburn, 2005, Pellow and Brulle 2005, Schlosberg 2007). However, traditional EJ literature tends to overlook the fact that residents also fight to achieve long-term equitable revitalization and improve the livability and environmental quality of their neighborhoods through parks, playgrounds, community gardens, fresh markets, and improved waste management. Furthermore, previous studies have not examined the role of historic marginalization, threats of displacement, collective identities, and political systems in framing the demands and strategies of these marginalized neighborhoods, especially in different cities and political systems across the world. My dissertation is motivated by this overarching question: How and why do residents of seemingly powerless marginalized neighborhoods proactively organize to improve environmental quality and livability? To answer this question, I focus on three sub-questions: In what ways do residents and organizations engaged in environmental quality initiatives perceive that their work allowed them to re-build their community from within? To what extent do the environmental struggles of marginalized communities represent a desire to achieve environmental gains as opposed to serving as a means to advance broader political agendas in the city? How do different political systems and contexts of urbanization shape the strategies and tactics that neighborhoods develop and how to they manage to advance their goals? My dissertation is built around an international comparative study of three critical and emblematic case studies of minority and low-income neighborhoods organizing for improved environmental quality and livability in three cities - Casc Antic (Barcelona), Dudley (Boston), Cayo Hueso (Havana), - which have all achieved comparable improved environmental and health conditions around parks and playgrounds, sports courts and centers, community gardens, urban farms, farmers' markets, and waste management. During my eight-month fieldwork in Barcelona, Boston, and Havana, I conducted semi-structured interviews with leaders of local organizations and NGOs working on improving environmental conditions, with a sample of active residents in each neighborhood, and with municipal agencies and policy-makers. Furthermore, I engaged in observation of events, as well as participant observation of projects focused on environmental improvements. Last, I collected secondary data on neighborhood development, land use, and environmental and health projects. This study reveals that activists in Casc Antic, Dudley, and Cayo Hueso use their environmental and health endeavors to holistically re-build and repair a broken and devastated community and build safe havens, associating environmental justice with community development, and improvements in physical health with mental health support. They also frame broader political goals in the city such as addressing stigmas about their place, controlling the land and its boundaries, and building a more transgressive and spontaneous form of democracy. These goals reflect and are reinforced by the attachment and sense of community they feel for their neighborhood. To develop their vision, residents select multi-faceted and multi-tiered strategies, which reveal common patterns across neighborhoods despite differences in political systems: collage and bricolage techniques, broad coalitions and sub-community networks, clever engagement with public officials and funders, and local identity and traditions. This research extends EJ theory by focusing on how residents and their supporters make proactive environmental and health claims and defend their vision for improved neighborhood conditions and safety, gain political power, and address inequalities in planning and land use decisions.<br>by Isabelle Anguelovski.<br>Ph.D.

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 65-66).<br>A novel humidification dehumidification desalination system was developed at the Rohseneow Kendall Heat Transfer Laboratory. The HDH system runs by having different pressures in the humidifier and dehumidifier. One of the components that will keep the different pressures is an expander. The expander specification is to work with a pressure ratio of 1.2 while having a high efficiency. Two approaches were developed to achieve this result, one was through the design of a turbine and the second was through the selection and testing of a car turbocharger. The design of a turbine is given in detail and follows the process given in "Design of High- Efficiency Turbomachinery and Gas Turbines" by David Wilson. The final design of the turbine blades was sand cast. Due to the sand casting process, cavitation on the blade material was shown and testing of the blades was not pursued for fear of fast fracturing. The second option of selecting a turbocharger is shown and the process which led to its selection is explained. Through such process a K03 turbocharger was selected to be suitable to run at the low pressure ratios with a moderate efficiency. Testing of the K03 was conducted. The static-to-static isentropic efficiency calculated was 53% ± 11% for a pressure ratio of 1.2 while the total-to-total isentropic efficiency 60% ± 14% at a pressure ratio of 1.2. The high error associated with the efficiencies are due to the turbine experiencing small temperature drops in the order of 10°C or less. The K03 turbocharger is meant to run at higher pressure ratios, in the order of 2 with a manufacturer specified efficiency of 70%. Running the K03 at a pressure ratio of 1.2 decreases the efficiency since its not specified to run at those low pressure ratios. If a turbine or a turbocharger is designed for the exact specifications of the desalination system, it can work with low pressure ratios and be highly efficient.<br>by Yoshio Samaizu Perez Zuniga.<br>S.B.

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 39-40).<br>The ANSI/ASHRAE 110 Method is the standard test for laboratory hood containment performance. Sulfur hexafluoride is specified as the gas most suitable for this test and is most commonly used. Sulfur hexafluoride use has potential negative environmental repercussions as it is a potent greenhouse gas with a global warming potential 22,800 times greater per mass than CO₂. The purpose of this study is to evaluate nitrous oxide, a much less environmentally destructive tracer gas, as a potential substitute in the ANSI/ASHRAE 110 Method. In accordance with ANSI standards, flow visualization, face velocity, and tracer gas tests were performed on numerous laboratory hoods of varying design. A mannequin was positioned in front of the center of the hood, and a MIRAN SapphlRe was used to measure the presence of each tracer gas. Direct comparisons of the concentrations of the two gases were dominated by a few high concentrations. For this reason, concentrations of both gases were log1O-transformed for statistical analyses. Laboratory hood dimensions and properties were found to affect the relationship between the gases. The hood area of opening and sash height were found to significantly (p<0.001) affect logjo(SF₆/ N₂O). Average face velocity also significantly (p<0.025) affected the log ratio. Neither gas was an adequate indicator of the behavior of the other. The linear best fit of the logs of the concentration ratio had a slope of 0.858, a y-intercept of 0.434, and an R² of 35.9% indicating a poor correlation. For N₂O to qualify as a substitute for SF6 there would need to be a strong correlation between gas concentrations that was consistent independently of hood conditions. This condition was not met. Nitrous oxide was found to not be a suitable substitute for sulfur hexafluoride in the ANSI/ASHRAE 110 Method.<br>by Eric J. Guffey.<br>S.B.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1997.<br>Includes bibliographical references (leaves 227-229).<br>Piping light represents the first tenable method for recovery and reutilization of lighting related heat. It can do this by preserving the energy generated at the lamp as radiative, departing from precedent and avoiding absorption of and re-emission of radiant heat as convection and conduction. Within thermodynamic limits, the radiant heat generated by an electric lamp or the sun is available for optical concentration and for reconstitution as a high thermodynamic quality power reservoir. Piping light from a large central lamp facilitates the decoupling of lighting related heat at the source, and also means that the efficiency of one central fixture can be stringently optimized instead of the multitude of fixtures it replaces in buildings. Luminous efficacy for a full-spectrum lamp decoupled of its infrared can be shown to approach theoretical limits of 250 lumens/watt. UV generated by the lamp, if coupled along with the illumination into the transport fibers, can be converted into visible radiation at the emitting end of the fiber, supplementing the light output. Fiber optics are used to carry information over long distances (actually encoded pulses of radiative IR), but certain fiber optics can carry tremendous amounts of energy. As fiber optics become more and more plentiful in telecommunications, their prices will come down. Cost and operating expense studies included in the final chapter of this thesis indicate that a large single source with light that is efficiently coupled and piped throughout a building's interior could reduce electric light consumption to one-fourth, and that even at current fiber pricing levels some systems can be competitive in initial cost to conventional lighting. Certain aspects of centralization suggest further reductions in cost and operating expenses such as centralized, instead of localized, relamping and cleaning, and eliminated requirements for thermal, electrical, and structural hardware at room fixture locations. The economic and technical feasibility of a central system depends on the simultaneous minimization of fiber aperture area and energy losses. Thermodynamically, the concentration of light for transport cannot surpass the energy density of the source. So such a system employs, at best, an optical process that preserves the extent of the source. That is, a high brightness source must be used to drive the system, regardless of the lamp's lumen output. High brightness lamps, then, can be viewed as an alternative to high efficacy lamps for increasing the energy performance of lighting systems in buildings. This thesis anticipates the existence of high brightness, high lumen lamps. The sun's 10,000 footcandles in peak conditions can be a potent contributor to the energy efficacy of buildings if a collection and utilization strategy is properly devised. At 100 sq. ft of available illumination for each sq. ft of collected sunlight, a scenario including simultaneous collection and distribution of electric light and heat and sunlight and solar heat in a building could reduce to near zero the energy consumed for lighting during peak sun conditions. Studies in this thesis indicate that an economically driven future role of solar energy in the lighting, heating, and cooling of buildings could very well revolve around keeping sunlight in the form of illumination and sunheat in the form of radiative heat, instead of converting both into electricity via photovoltaics and reconversion of this electricity back into electric light. Conventional lighting is an inefficient process, essentially using heat sources for the light they provide. Not only is lighting related electricity generating predominantly waste heat, this heat must be removed from the building's envelope by an additional input of energy. Even energy saving fluorescent lamps and fixtures produce at least 80% heat. This might serve to explain why 30% of the country's electricity is consumed by lighting. This thesis proposes a method for decoupling and recovery of lighting related heat, and transporting light in lieu of electricity to lighting fixtures (Chapters 2 and 6). Each of the optical components that would comprise such a system is examined. Chapter 7 investigates the radiation source. Chapter 8 develops the source reflector which will direct the source's radiative output in a particular direction. Chapter 9 studies a mirror that will separate the source's radiation beam into a light beam and a heat beam for subsequent processing. Chapter 10 looks at the heat collector that will convert the heat beam into a usable high-temperature power reservoir. Chapter 11 devises the light collector/ concentrator that will facilitate coupling of light energy into a fiber optic transport network. Chapter 12 assembles the constituent components into central modules. Chapter 5 surveys the light transport media, in particular fiber optics and Prism Optical Light Guide, for suitability to building lighting applications. The exact method of solar couplature is not introduced. Sample energy efficiency comparisons, cost and payback scenarios, implementation issues and concepts for room emitters are included in chapter 13. Related concepts for a transparent concentrating solar collector for use as a window or skylight, and a solar concentrating wall are disclosed in the conclusory chapter. Material included in this thesis has been patented by MIT. The usage of such material for any commercial means requires a licensing agreement.<br>by Kurt Antony Levens.<br>S.M.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 134-140).<br>Porous wicks for use in a loop heat pipe were sintered from copper and Monel powder. These wicks were characterized in terms of their shrinkage, porosity, thermal conductivity, liquid permeability and maximum capillary pressure. The effect of fabrication parameters (particle size and sintering conditions) on these properties was studied. Shrinkage was found to increase with increasing sintering time and temperature. Porosity followed the opposite trend. For a given sintering temperature, thermal conductivity of the samples was found to increase as the sintering time increased. Permeability and capillary pressure were found to be independent of the sintering time as long as the wick stayed bonded to the walls of its container. In addition to measuring the properties of the wicks, a model for predicting their thermal conductivity was developed. First, the so-called 'two-sphere model' is used to relate the sintering conditions to the size of the connections between particles (referred as 'necks'). Then, a finite element simulation was used to determine the thermal resistance of diverse unit cells as a function of the neck size between the particles. Finally a MATLAB simulation program was written to generate a random 3D resistor network as means to model the multiple connections between spheres in a wick. The MATLAB code was used to calculate the effective thermal conductivity of the wick. Comparison of the model predictions with the experimental data showed good agreement.<br>by Francisco Alonso Dominguez Espinosa.<br>S.M.

La presente Memoria de Experiencia Laboral tiene como objetivo esclarecer las funciones del cargo de Enlace Administrativo Distrital, tanto desde el ámbito histórico y técnico como a partir de mi experiencia personal. INSTITUTO NACIONAL ELECTORAL. Uno de los problemas más comunes en el cargo son los atrasos en el cumplimiento de las actividades programadas por la Coordinación Administrativa, el cual se agrava por la falta de un auxiliar que apoye en el cumplimiento de las mismas y la mala coordinación que existe entre los departamentos ya que las actividades tienden a empalmarse, complicando el cumplimiento de las mismas.

Esta investigación tiene como objeto de estudio el sistema de profesionalización en la administración pública federal en México, en particular lo referente a la Ley del Servicio Profesional de Carrera en la Administración Pública Federal centralizada, del 10 de abril del año 2003; con objeto de poder analizar sus avances en la práctica laboral y la normatividad pertinente, así como encontrar sus fallas y proponer líneas de acción. Hay un reconocimiento en la literatura especializada y en opinión pública que la profesionalización del servicio público es un tema relevante en la agenda de la modernización de las instituciones. Sin embargo, es pertinente preguntarse por los problemas públicos que pretende resolver la profesionalización en la función pública. Incluso cada que surge una controversia con respecto a la calidad del servicio de parte de los organismos gubernamentales se recurre al tópico de la preparación/habilidades profesionales de los servidores públicos. Por si fuera poco, es un punto de debate cotidiano en la sociedad, quien encuentra en el servidor público un enemigo más que un aliado. La necesidad de la ciudadanía para que la función pública sea más eficiente, competitiva y democrática, fue lo que obligó al gobierno a tener que modernizar los mecanismos de la gestión pública. Hoy día, es requisito contar con un servicio de carrera profesionalizado para la correcta gestión y dirección de los asuntos públicos, el cual, a su vez, se convierte en un indicador de su capacidad para dar respuesta a las demandas y exigencias sociales.

Las redes metal-orgánicas MOF (por sus siglas en inglés, Metal Organic Frameworks) materiales poroso eficaces en la adsorción y separación de gases principalmente CO2. En esta tesis se sintetizó exitosamente una membrana de un nuevo BioMOF de Zinc basado en adenina y ácido benceno-1,3,5-tricarboxilico (BTC) mejor conocido como ácido trimésico. El método de preparación de la membrana fue crecimiento secundario, se caracterizó por difracción de rayos X en polvos (PXRD), microscopía de barrido electrónico (SEM), espectroscopia infrarroja y además se realizó el análisis de permeación para los gases H2, N2, CO2, propano y propeno. La membrana bien integrada por cristales de aproximadamente 12.3 μm de largo. Los estudios de permeabilidad mostraron valores de adsorción de 2.71259 x 10-6 CO2, 1.14109x10-5 H2, 3.39432 x 10-6 N2, 4.0095 x10-6 C3H8 y 3.4905 x10-6 C3H6 ( molm2 s Pa ) lo que mostró que la membrana posee una selectividad de 4.21 para CO2 respecto al hidrógeno. De manera paralela se sintetizó una membrana del ya reportado por Rosi BioMOF-1 para fines de comparación. Nuestra membrana presentó valores de permeación y selectividad similares a los del BioMOF-1 a pesar de tener un tamaño de poro menor (15 Å vs 30 Å) lo que se atribuye a los nitrógenos de adenina y oxígenos de carboxilatos no coordinados. Dado los resultados obtenidos, la membrana de BioMOF sintetizada se propone como un nuevo material hِíbrido poroso biocompatible de gran interés para su futura aplicación en adsorción y separación de gases desde una perspectiva ambiental y energética.

Se utilizaron 32 ovinos machos (25 ± 0.580 kg PV) para evaluar el efecto de suplementar el clorhidrato de zilpaterol (CZ) y metionina de zinc (ZM) sobre el crecimiento, características de la canal y calidad de la carne. Se utilizó un diseño completamente al azar, con arreglo factorial 2x2, dos niveles de CZ (0 y 0.2 mg kg-1 PV d-1) y dos niveles de ZM (0 y 80 mg kg-1 MS). El CZ aumentó (P<0.05) el rendimiento en canal, el índice de compacidad, el área de ojo de chuleta y disminuyó el engrasamiento (P <0.02). El contenido de extracto etéreo en la grasa intramuscular de la carne aumentó (P<0.05) en los ovinos suplementados con ZM mas CZ y en los que recibieron sólo ZM (P<0.0001). El CZ aumentó (P<0.05) el contenido de proteína cruda en la carne y disminuyó (P<0.002) los valores de color L*, a*, b*, C*, y H°. Por lo tanto, se concluye que el CZ aumenta el rendimiento de la canal, y disminuye su engrasamiento; el aumento del contenido de extracto etéreo en la carne por efecto de ZM, CZ más ZM y en el contenido de proteína por efecto del CZ implica que el uso de estos aditivos en la producción de ovinos en engorda puede influir sobre la calidad de la carne.

Tesis de doctorado<br>Se evaluó el efecto de biopolímeros con extractos antioxidantes sobre la vida útil de un restructurado cárnico, almacenado a 4°C. Se llevaron a cabo cuatro etapas, en la primera etapa el reestructurado cárnico fue a base de carpa común (Cyprinus carpio) y cerdo (0:100; 100:0) fortificado con 0-8 g / 100 g de harina de semilla de chía (CSF). Para seleccionar el mejor reestructurado se realizó la evaluación textural y sensorial observándose que el reestructurado cárnico con características idóneas fue la base de carpa: cerdo, 75:25 con 8 % de harina de chía, con un color similar a un producto tipo integral. En la segunda etapa se obtuvo un biopolímero a base de suero de leche, inulina, grenetina, glicerol y extracto acuoso de (Hibiscus safdariffa L.) sustituyendo el contenido de agua (50 %), el cual presentó un contenido de compuestos fenólicos de 392.13 mgAGE/g. En la tercera etapa fue la aplicación biopolímero sobre el reestructurado y se evaluó el efecto durante su vida de anaquel, observándose que al transcurrir el tiempo de almacenamiento (23 días), el color no tuvo diferencia significativa, el recubrimiento con y sin extracto acuoso mantuvieron estable la humedad con respecto al control, quién tuvo una disminución significativa (p<0.05), en cuanto al contenido de bases volátiles totales, ambos polímeros (con y sin extracto acuoso de Jamaica) provocaron una disminución en la producción de estos compuestos, respecto a la textura, ambos recubrimientos tuvieron un efecto protector de los reestructurados, ya que las proteínas se vieron menos afectadas manteniendo por más tiempo la integridad del reestructurado cárnico. El perfil electroforético SDS-PAGE, mostró que las muestras con biopolímero coadyuvaron a mantener la integridad de la miosina durante el tiempo de almacenamiento, no siendo así para la muestra sin polímero. Respecto a los análisis microbiológicos, se observó que los reestructurados con biopolímero disminuyeron la velocidad de crecimiento de los microorganismos. Este estudio muestra que la aplicación de biopolímeros activos adicionados con extracto de Hibiscus safdariffa L., son una estrategia que retarda los cambios fisicoquímicos y microbiológicos de descomposición almacenados a bajas temperaturas (-4 °C).

Kyoto University (京都大学)<br>0048<br>新制・課程博士<br>博士(エネルギー科学)<br>甲第13174号<br>エネ博第148号<br>新制||エネ||36(附属図書館)<br>UT51-2007-H447<br>京都大学大学院エネルギー科学研究科エネルギー基礎科学専攻<br>(主査)教授 森井 孝, 教授 木下 正弘, 教授 牧野 圭祐<br>学位規則第4条第1項該当

L’abiratérone (Abi) est un inhibiteur de synthèse des androgènes de type stéroïdien utilisé dans le traitement du cancer de la prostate. Le métabolisme de l’Abi entraîne la formation de métabolites pharmacologiquement actifs agissant soit comme inhibiteur de synthèse, antagoniste ou agoniste du récepteur androgénique. Leur concentration plasmatique est très variable alors que la suppression androgénique suivant le traitement varie considérablement. L’action de la voie métabolique de glucuronidation sur ces composés de type stéroïdien n’est pas connue. Cette voie enzymatique, médiée par les enzymes UGT, représente une étape clé du métabolisme des médicaments et de l’homéostasie de nombreuses molécules endogènes incluant un rôle primordial dans la régulation des voies hormonales ciblées par l’Abi. L’objectif de mes travaux était d’évaluer le métabolisme de l’Abi par la voie de glucuronidation, d’étudier l’effet potentiel de la variabilité génétique de cette voie et enfin, d’explorer une possible interaction avec la glucuronidation des stéroïdes. Les données recueillies révèlent que l’Abi et ses métabolites actifs sont conjugués par l’enzyme hépatique UGT1A4 in vitro et confirment que ces nouveaux métabolites sont présents en circulation chez les patients traités. Plusieurs variations polymorphiques du gène UGT1A4 entraînent une perte de fonction de l’enzyme et une réduction significative de l’inactivation de l’Abi et de ses métabolites in vitro, suggérant que les patients porteurs de ces polymorphismes génétiques pourraient être exposés à des concentrations plus élevées des composés pharmacologiques actifs. L’importance de cette voie métabolique demeure à être établie in vivo. De plus, nos données révèlent que l’Abi et ses métabolites sont des inhibiteurs puissants de l’inactivation des androgènes et de leurs précurseurs surrénaliens par la voie des UGT tant au niveau du foie que des cellules cancéreuses prostatiques. Ces découvertes laissent présager que la relation entre l’exposition à l’Abi et à ses métabolites, la suppression androgénique subséquente en cours de traitement à l’Abi et, ultimement, la réponse clinique des patients est complexe. Une étude plus approfondie des facteurs génétiques et pharmacologiques ainsi qu’un profilage plus complet des hormones stéroïdiennes chez les patients traités est nécessaire afin d’identifier de nouveaux marqueurs prédictifs de la réponse à la thérapie antihormonale.<br>Abiraterone (Abi) is a selective steroidal inhibitor of androgens biosynthesis used for the treatment of advanced prostate cancer. Abi is known to be metabolised into pharmacologically active metabolites having either androgen synthesis inhibitor activity or antagonistic/agonistic activity toward the androgen receptor. Plasma concentration of these metabolites and androgen suppression are highly variable between treated patients. The activity of UGT enzymes toward these steroidal molecules is currently unknown. This pathway mediated by UGT enzymes is a key step in the metabolism of drugs and endogenous molecules. These enzymes have a primary role in the regulation of hormonal pathway targeted by Abi. We aimed to study the metabolism of Abi by the glucuronidation pathway, the genetic variability of UGT enzymes as well as the impact of this pathway on steroids inactivation. Data obtained point out UGT1A4 as the main enzyme implicated in the glucuronidation of Abi and its metabolites in the liver and they also show significant circulating levels of these new metabolites within treated patients. Moreover, many polymorphisms in this metabolic pathway lead to a loss of function of UGT1A4 and to the abrogation of the inactivation of Abi and its metabolites, suggesting that carriers of these polymorphisms might be exposed to higher concentrations of pharmacologically active metabolites. Finally, additional data revealed potent inhibitor activity of Abi and its metabolites toward androgens and adrenal precursor’s inactivation by UGTs expressed in liver and prostatic tissues. Our study shows that the relationship between the exposition to Abi and its metabolites, the androgenic suppression and the clinical response observed in treated patients is complex and suggest that genetic, pharmacologic and metabolomic analysis could allow the identification of new predictive biomarquers of the response toward the antihormonal therapy in patients treated with Abi.

La tomate (Solanum lycopersicum) est largement appréciée par les consommateurs. La flaveur distinctive des tomates provient des interactions entre les acides, les sucres et un mélange complexe de composés volatils. Ces substances volatiles sont principalement dérivées de nutriments tels que les caroténoïdes, les acides gras et les acides aminés. Bien que la tomate soit considérée comme un modèle pour le développement des fruits, la plupart des voies métaboliques menant à la synthèse de volatils ne sont pas encore bien comprises. Afin de mieux interpréter les sentiers métaboliques, nous avons quantifié une centaine de composés volatils dans 254 accessions de tomates ancestrales, modernes et sauvages. Nous avons sélectionné 64 de ces cultivars en fonction de leur profil aromatique et réalisé une étude transcriptomique. Nous avons utilisé un modèle de régression linéaire et une étude d'association pangénomique pour évaluer la relation entre les composés volatils et l'expression génique afin de mieux comprendre la régulation génétique des diverses voies métaboliques. L'analyse de la population a démontré que le profil en composés volatils varie considérablement entre les divers cultivars de tomates. Les composés volatils à l'intérieur d'un même sentier métabolique sont par contre fortement corrélés entre eux. La force de ces corrélations diffère considérablement, indiquant la présence d'étapes limitantes. De fortes corrélations entre des composés volatils non apparentés indiquent également des liens possibles entre différentes voies de biosynthèse. L'émission différentielle de plusieurs volatils dans la population de cultivars de tomates corrèle fortement avec l'expression des gènes caractérisés et d'autres gènes candidats. L'étude d'association pangénomique a permis de cibler de courtes régions chromosomiques associées à l'émission de certains groupes de composés volatils dans le fruit. Nos résultats démontrent le potentiel de ces différentes approches pour mieux comprendre les voies métaboliques de biosynthèse des composés volatils et découvrir de nouveaux gènes candidats.<br>Tomato (Solanum lycopersicum) is widely appreciated by consumers. The distinctive flavor of tomatoes comes from the interactions between acids, sugars and a complex mixture of volatile compounds. These volatiles are mainly derived from nutrients such as carotenoids, fatty acids and amino acids. Although tomato is considered a model for fruit development, most of the metabolic pathways leading to volatiles synthesis are not yet fully understood. In order to better understand these metabolic pathways, we quantified about 100 volatile compounds in 254 accessions of heirloom, modern and wild tomatoes. We selected 64 tomatoes cultivars based on their aroma profile and performed a transcriptomic analysis. We used a linear regression model and a genome-wide association study to evaluate the relationship between volatile compounds and gene expression, in an effort to better understand the genetic regulation of the various metabolic pathways. The volatiles profile varied considerably among tomatoes cultivars. Volatile compounds within the same metabolic pathway were strongly correlated with each other. On the other hand, the strength of these correlations differed considerably, indicating the presence of limiting steps. Strong correlations between unrelated volatile compounds also indicate possible links between different biosynthetic pathways. The differential emission of several volatiles in the tomato cultivar population strongly correlates with the expression of characterized genes and other candidate genes. A genome-wide association study was used to target short chromosomal regions associated with the emission of certain groups of volatiles in the fruits. Our results demonstrate the potential of these different approaches to better understand the metabolic pathways leading to the biosynthesis of volatile compounds and to uncover new candidate genes.

Les cellules souches neurales (CSNs) persistent dans la zone sous ventriculaire dans le cerveau adulte. Elles transitent d’un état quiescent à un état prolifératif afin de produire de nouveaux neurones. Les mécanismes régulant cette transition restent cependant méconnus. Les CSNs adultes étant enrichies en gènes calciques, nous avons déterminé si la transition d’un état quiescent vers un état de prolifération était calcium-dépendant. Pour ce faire, nous avons utilisé des mini-endoscopes miniatures pour observer la division cellulaire et sa régulation par la signalisation calcique chez la souris en mouvement libre. Nos données révèlent différents dynamiques calciques et niveaux intracellulaires calciques lors de la division des CSNs. Les expériences pharmacologiques et la technique d’édition génomique CRISPR-Cas9 montrent que les réserves intracellulaires calciques IP3-dépendant et les régulateurs à la protéine G régulent la transition d’un état quiescent vers l’état prolifératif. Nous avons aussi utilisé une approche optogénétique in vivo afin de mimer la dynamique calcique des CSNsquies centes pour maintenir les CSNs dans un état de quiescence et bloquer son activation vers un stade prolifératif. Nos résultats démontrent que les dynamiques calciques et le niveau intracellulaire calcique jouent un rôle important dans l’activation des CSNs. Ensuite, nous avons investigué le microenvironnement des CSNs notamment les vaisseaux sanguins et leur rôle dans la physiologie des CSNs. Les CSNs étendent un long prolongement basal et contactent les vaisseaux sanguins. Le contact direct et la libération de facteurs par les cellules endothéliales influencent le comportement des CSNs. Ici, nous avons utilisé des souris transgéniques pour altérer la communication entre les vaisseaux sanguins et les CSNs. Comme la signalisation Notch joue un rôle clé dans la signalisation des vaisseaux sanguins, nous avons inhibé in vivo la signalisation Notch spécifiquement dans les cellules endothéliales. Nous avons trouvé que l’inhibition de la signalisation Notch dans les cellules endothéliales à des stades précoces (P0) ou à des stades tardifs (P30) augmentait le nombre de CSNs. L’analyse morphologique des vaisseaux sanguins révèle aucune altération quand Notch est inhibé à des stades tardifs (P30). Ces résultats montrent que l’inhibition de la signalisation Notch maintient lesCSNs dans un état de quiescence.<br>Neural stem cells (NSCs) persist in the subventricular zone of adult brain and transit from the quiescent to the proliferative states to produce new neurons. The mechanisms regulating the transition froma quiescent to a proliferative state remain unclear. Since adult NSCs are enriched in genes associated with Ca2+ signalling pathways, we aimed to determine whether the transition from quiescence to aproliferative state is Ca2+ dependent. Here, we used miniature endoscopes (mini-endoscopes) to monitor NSC division and their regulation by Ca2+ signalling in freely behaving mice. Our data revealeddifferent Ca2+ dynamics and steady-state Ca2+ intracellular levels during NSC division. Pharmacological and in vivo CRISPR-Cas9 gene editing showed that IP3-sensitive intracellular stores and G-proteins regulators regulate the transition from quiescence to proliferation. We further used in vivo optogenetics to mimic Ca2+ dynamics of quiescence state to maintain NSCs in this state and prevent NSCsto transit into proliferative state. Our results demonstrate that Ca2+ dynamics and Ca2+ intracellularlevels play an important role in NSC activation. Next, we investigated NSCs microenvironmentmainly blood vessel and their role in their physiology. The NSCs contact the blood vessels by extending their basal processes. Direct cell-cell contact and the release of factors such as VEGF (vascularendothelial growth factor) by endothelial cells (EC) influence the NSC behaviour. As Notch pathwayis a key player in vasculature signalling, we inhibit in vivo the Notch signalling specifically in EC.We found that inhibition of Notch signalling in EC at early stage (P0) or later stage (P30) increasesNSC number. Morphological analysis of blood vessel reveals no alteration when Notch signalling isinhibited at later stages (P30). These finding showed that inhibition of Notch signalling in EC maintains NSC in quiescence state.

L'objectif de cette thèse est d'analyser les implications économiques des mesures techniques non tarifaires (MTNT) en vigueur dans les pays développés sur le commerce international de produits agroalimentaires des pays Africains. De façon plus spécifique, elle s'intéresse à trois questions principales. La première, qui est plus générale, est de savoir quel est et qu'est-ce qui détermine l'effet net de l'ensemble des mesures techniques non tarifaires en vigueur dans les pays de l'OCDE sur les exportations Africaines de produits végétaux. La deuxième question, plus spécifique, cherche à savoir quels sont les effets de la conformité aux mesures de limites maximales de résidus (LMR) de pesticides sur la production, l'offre d'exportation et la demande d'importation. Finalement, la troisième question consiste à déterminer quel est l'impact direct des rejets de produits à la frontière des pays Européens du système d'alerte rapide pour les denrées alimentaires et les aliments pour animaux (RASFF) sur les exportations Africaines de fruits et légumes comestibles. Nous traitons ces différentes questions à travers trois essais. Dans le premier essai, nous analysons de façon théorique l'effet net des MTNT sur le commerce bilatéral et proposons une approche empirique robuste pour évaluer cet effet. Ensuite, nous évaluons les effets d'entrave et d'amélioration ainsi que l'effet net des MTNT en vigueur dans les pays de l'OCDE sur les exportations africaines de produits végétaux. Nos résultats théoriques montrent que l'effet net des MTNT sur le commerce bilatéral agrégé dépend non seulement de l'élasticité de substitution et de l'élasticité du coût marginal par rapport aux MTNT, mais aussi du paramètre de forme de la distribution des coûts marginaux qui dépend de la technologie. En plus, nous constatons que pour une élasticité de substitution donnée, seules les entreprises ou les pays caractérisés par un coût marginal inférieur à un coût marginal seuil et une productivité supérieure à un niveau de productivité seuil connaîtront un effet net positif du commerce vers une destination donnée. Pour nos investigations empiriques, nous estimons une équation de gravité sectorielle en utilisant la base de données des MTNT publiée par la CNUCED et le WITS, combinée aux données commerciales transversales pour 2017 de UN COMTRADE/WITS. Les données couvrent 53 pays africains exportant 40 produits végétaux à 4 chiffres du Système harmonisé (SH) vers 35 pays membres de l'OCDE. Nos résultats empiriques montrent à la fois des effets d'entrave (diminution de 3,099%) et d'amélioration (augmentation de 2,056%) des MNT en vigueur dans les pays de l'OCDE sur les exportations africaines de produits végétaux. Ensemble, ces effets produisent un effet net négatif et significatif, ce qui indique que les MNT en vigueur dans les pays membres de l'OCDE constituent des obstacles pour les exportateurs Africains de produits végétaux. Dans le second essai, nous démêlons théoriquement et empiriquement les effets des LMR pour les pesticides sur la production, l'offre d'exportation et la demande d'importation. Nous adoptons une approche de modélisation basée sur les coûts et les bénéfices associés aux normes de sécurité sanitaire des aliments et utilisons notre cadre théorique pour évaluer les effets empiriques nets des LMR de pesticides sur la production de mangues en Afrique et le commerce avec les pays membres de l'OCDE. Théoriquement, nous montrons que les effets des LMR sur la production sont négatifs tandis que leurs effets nets sur le commerce bilatéral peuvent être positifs, nuls ou négatifs selon que l'effet de la qualité perçue par les consommateurs sur la demande d'importation est supérieur, égal ou inférieur à l'effet du coût de mise en conformité sur l'offre d'exportation. Nous utilisons des données transversales pour 12 pays africains qui ont produit et exporté des mangues conformes aux LMR vers 31 pays de l'OCDE en 2016, et nous constatons que, d'une part, les effets nets des LMR de pesticides sur la production de mangues sûres sont négatifs. D'autre part, ils sont positifs sur le commerce des mangues entre les pays africains et les pays membres de l'OCDE. Nos résultats impliquent que le renforcement ou l'imposition de LMR strictes pour les pesticides dans les pays développés peut favoriser les échanges commerciaux alors qu'ils entravent fortement la production dans les pays africains. Dans le dernier essai, nous évaluons l'effet des refus d'importation des pays Européens sur les exportations Africaines de fruits et légumes comestibles, au cours de la période 2008 à 2018. De façon plus spécifique, nous estimons l'effet moyen des rejets aux frontières des pays du réseau RASFF sur les marges extensive et intensive de commerce de fruits et légumes comestibles pour 45 pays africains. Nous utilisons les données sur les rejets aux frontières issues de la base de données en ligne du RASFF avec les données sur les exportations Africaines provenant de la base de données de WITS des Nations Unies. Nous estimons la version canonique de l'équation de gravité sectorielle d'Anderson et al. (2004) en utilisant l'estimateur du Pseudo poisson maximum de vraisemblance (PPML) de Silva et al.(2006) en combinaison avec l'approche robuste d'estimation à deux étapes avec inclusion de résidus (2SRI) de Terza et al.(2008). Nous constatons qu'une augmentation du nombre de refus d'importation par un pays du RASFF une fois dans l'année en cours entraîne une diminution du nombre de partenaires commerciaux en Europe pour les pays africains de 0,018% pour les légumes comestibles et de 0,143 % pour les fruits comestibles. En outre, nos résultats montrent qu'un refus d'importation supplémentaire diminue la valeur des exportations de légumes comestibles des pays africains de 0,045%. Cependant, nous constatons que les refus d'importation des pays du RASFF une fois dans l'année en cours entraînent une augmentation de la valeur des exportations de fruits comestibles des pays africains de 0,126%. Par ailleurs, nos résultats valident explicitement l'hypothèse d'endogénéité du nombre de refus d'importation et mettent en évidence les effets directs et les effets de contagion des rejets aux frontières. Ce dernier résultat signifie qu'une augmentation du nombre de rejets à la frontière d'un produit donné (par exemple un fruit frais) au cours d'une année précédente entraîne une augmentation du nombre de rejets à la frontière pour ce produit et les produits voisins (par exemple un légume frais) au cours de l'année suivante.<br>The objective of this thesis is to analysis the economic implications of technical non-tariff measures (TNTMs) in force in developed countries on the international trade of agricultural and agri-food products of African countries. More specifically, we focus on three main issues. The first more general question is: what is and what determines the net effect of the set of TNTMs in OECD countries on African exports of plant products ? The second, more specific, question is: what are the effects of compliance with maximum residue limit (MRL) for pesticide on production, export supply and import demand ? Finally, the third question is to determine: what is the direct impact of product rejections at the border of European countries of the Rapid Alert System for Food and Feed (RASFF) on African exports of plant products ? We address these different questions through three essays. In the first essay, we theoretically analyze the net effect of technical non-tariff measures (TNTMs) on bilateral trade and suggest a robust empirical approach to evaluate this effect. We assess the impediment, enhancement and net effects of the TNTMs in force in OECD countries on African exports of plant products. Our theoretical findings highlight that the net effect of the TNTMs on aggregate bilateral trade depends not only on the elasticity of substitution and the elasticity of marginal cost with respect to the TNTMs but also the shape parameter of the distribution of marginal costs which depends on the technology. In addition, we find that for a given elasticity of substitution, only firms or countries characterized by a lower marginal cost than a cutoff marginal cost and higher productivity than a threshold productivity level will experience a positive net effect of trade to a given destination. For our empirical investigation, we estimate a sectoral gravity equation using the non-tariff measures (NTMs) database released by UNCTAD and WITS combined with cross-sectional trade data for 2017 from the UN COMTRADE/WITS database. The data cover 53 African countries exporting 40 Harmonized System (HS) 4-digit plant products to 35 OECD member countries. Our empirical results show both impediment (decrease of 3.099%) and enhancement (increase of 2.056%) effects of the TNTMs in force in OECD countries on African exports of plant products. Together, these effects yield a negative and significant net effect, which indicates that the TNTMs in force in OECD member countries are obstacles for African exporters of plant products. In the second essay, we disentangle theoretically and empirically the effects of the MRLs for pesticides on the production, export supply and import demand. We adopt a modelling approach based on the costs and benefits associated with food safety standards and use our theoretical framework to assess the empirical net effects of the MRLs for pesticides on African mango production and trade with OECD member countries. Theoretically, we show that the production effects of MRLs are negative while their net effects on bilateral trade can be positive, zero or negative depending on whether the consumers' perceived quality effect on import demand is greater than, equal to or less than the compliance cost effect on export supply through the unconditional expected standard-compliant production. We use a cross-sectional data set for 12 African countries that produced and exported MRL-compliant mangoes to 31 OECD countries in 2016, and find that, on the one hand, the net effects of MRLs on the production of safe mangoes are negative. On the other hand, they are positive on mango trade between African and OECD member countries. Our results highlight that the tightening or imposition of strict MRLs for pesticides in developed countries may be trade promoting while they severely impede production in African countries. In the last essay, we assess the effects of European countries' import refusals on African exports of edible vegetables and fruits from 2008 to 2018. We specifically estimate the average effects of the RASFF countries' border rejections on the extensive and intensive margins of African countries exports of edible vegetables and fruits. We use the border rejections data from the RASFF online database and export data on 45 African countries from the UN WITS database. We estimate the canonical version of the sectoral gravity equation of Anderson and al. (2004) using the Poisson pseudo maximum likelihood (PPML) estimator of Silva and al. (2006) in association with the robust twostage residual inclusion (2SRI) approach of Terza and al. (2008). We find that a single increase in the number of import refusals by a RASFF country in the current year leads to a decrease in the number of trade partners in Europe for African countries by 0.018 percent for edible vegetables and 0.143 percent for edible fruits. In addition, our results show that one additional import refusal decreases the export value of African countries' edible vegetables by 0.045 percent. However, we find that RASFF countries' refusal to import once in the current year leads to an increase in the export value of African countries' edible fruit by 0.126 percent. Furthermore, our results explicitly validate the hypothesis of the endogeneity of the number of import refusals and highlight both the direct and spillover effects of border rejections. The latter result means that an increase in the number of border rejections for a given product (for instance, a fresh fruit) in a given year leads to an increase in the number of border rejections for a product and its neighboring products (for instance, a fresh vegetable) in the next year.

Dans la province du Haut-Katanga, en République démocratique du Congo (RD Congo), une forte pression anthropique est exercée sur la forêt claire (FC, Miombo) par l’agriculture et la demande accrue en charbon de bois, due à la croissance démographique. La restauration de la FC dégradée est devenue essentielle pour renverser cette régression et gérer durablement la FC. L’objectif principal de cette thèse était d’étudier la croissance de semis et le potentieldes champignons mycorhiziens arbusculaires (CMA). Elle avait pour objectifs spécifiques:(i) d’évaluer la croissance et le statut mycorhizien des espèces forestières de la FC, en lien avec le statut de succession, espèces pionnières (EP) et tardives (ET); (ii) de déterminer le potentiel d’inoculum mycorhizien arbusculaire (PIMA) dans la FC dégradée; et (iii) de décrire la communauté des CMA, associés à un arbre forestier à usage multiple (Pterocarpustinctorius Welw ou Mninga maji en Swahili, Mukula en Bemba).D’abord, la croissance des semis a été évaluée, pour deux espèces d’arbres pionnières(Combretum collinum et Pterocarpus tinctorius) et six espèces tardives (Brachystegiaboehmii, B. longifolia, B. spiciformis, B. wangermeana, Julbernardia globiflora et J.paniculata), 1, 2 et 4 ans après la plantation. Ensuite, le PIMA a été évalué par le piégeage des plantules de Crotalaria juncea dans la FC dégradée. La relation entre le PIMA et les indices de végétation a été établie avec les modèles linéaires généralisées mixtes (MLGM)et les régressions linéaires. En dernier lieu, la diversité et la structure de la communauté des CMA des racines de P. tinctorius ont été caractérisées dans les jachères agricoles et forestières de trois sites, par amplification, clonage du gène 28S de la grande sous-unité(LSU) de l’ADN ribosomal et le séquençage Sanger. Les résultats montrent que les espèces forestières pionnières (EP, Chipya) avaient une croissance précoce et une productivité 3 à 40 fois supérieure comparées aux ET (typique du Miombo). Les espèces pionnières étaient colonisées par les CMA, alors que les espèces tardives l’étaient par les ectomycorhizes. Par ailleurs, la densité des arbres des EP influence positivement le PIMA, particulièrement les légumineuses ligneuses agissant en synergie avec l’abondance des herbacées annuelles. Par leur colonisation mycorhizienne élevée, les légumineuses ligneuses seraient les plantes refuges des CMA. Finalement, une diversité moléculaire de 30 unités taxonomiques opérationnelles (UTOs) des CMA était associée à P.tinctorius (une des légumineuses ligneuses mycotrophes), dans les friches agricoles et forestières de trois sites étudiés. La richesse spécifique et la structure de la communauté des CMA étaient influencées par la densité des espèces ligneuses, colonisées par les CMA, équitablement réparties dans les espèces végétales. De plus, la communauté des CMA était dominée par les espèces du genre Rhizophagus et Sclerocystis, qui étaient fortement associées à certaines propriétés chimiques du sol (pH, acidité, Al et Fe total) et à la densité de quelques arbres. Ainsi, les résultats mettent en évidence une variabilité de la croissance et de la biomasse en fonction du statut de succession (groupes écologiques). Aussi, le PIMA et la communauté des CMA étaient contrôlés par la densité des arbres et quelques propriétés du sol. Nous suggérons la reforestation de la forêt claire dégradée avec les espèces indigènes (P.tinctorius, B. spiciformis et C. collinum), en plantations mono spécifiques ou en régie agroforestière avec les cultures vivrières.<br>In the Katanga province, Democratic Republic of the Congo (DR Congo), the anthropogenic pressure is exerted on the Miombo woodland (MW) with the expansion of the agricultural lands and the increased demand for charcoal, due to the demographic growth. The restorationof agricultural and forest fallows has become essential to reverse this decline and sustainably manage the degraded MW. The main objective of this thesis was to study the development of seedlings and the potential of arbuscular mycorrhizal fungi (AMF) in the MW of UpperKatanga, DRC. Its specific objectives were to: (i) assess the development and mycorrhizalstatus of MW species, with respect to their successional status (early (ES) or late (LS) tree species); (ii) determine the arbuscular mycorrhizal inoculum potential (AMIP) in degradedMW; and (iii) describe the diversity and community structure of AMF associated with amultipurpose forest tree (Pterocarpus tinctorius Welw also named Mninga maji in Swahili,Mukula in Bemba).First, the development of the seedlings was evaluated, for two pioneer tree species(Combretum collinum and P. tinctorius) and six late species (Brachystegia boehmii, B.longifolia, B. spiciformis, B. wangermeana, Julbernardia globiflora and J. paniculata), 1, 2and 4 years after planting. Then, the AMIP was estimated in degraded MW by baitingCrotalaria juncea seedlings. The relationship between AMIP and vegetation indix wase stablished with Generalized Linear Mixed Models (GLMM) and linear regressions. Finally, the diversity and the structure of the AMF community in the roots of P. tinctorius were characterized in the agricultural and forest fallow of three sites, by amplification, cloning of the 28S gene of the large subunit (LSU) of the ribosomal DNA and Sanger sequencing. The results showed that the early successional tree species, ES (Chipya) had early growthand were 3 to 40 times more productive than to LS (tree species characteristic of MW). ESspecies were colonized by AMF, whereas LS species were colonized by ectomycorrhizal fungi. In degraded MW, the density of some trees had a positive influence on AMIP,particularly woody legumes acting synergistically with the abundance of annual grasses.Woody legumes were more colonized and would act as AMF plant refuges. Molecular diversity of 30 operational taxonomic units (UTOs) of AMF was associated with P. tinctorius (one of the mycotrophic woody legumes), in the agricultural and forest fallows of three sites studied. The community richness and structure of the AMF were driven by the density ofwoody species colonized by AMF evenly distributed in plant species. The AMF communitywas dominated by species of the genera Rhizophagus and Sclerocystis, and were strongly associated with some chemical properties of the soil (pH, acidity, total aluminium and totaliron) and the density of some trees. Thus, the results highlight a variability of growth and biomass depending on the successional status (ecological groups). Also, the AMIP and the AMF communities were mainly driven by tree density and soil properties. We suggest there forestation of degraded MW with the native species (P. tinctorius, B. spiciformis and C.collinum) in mono-specific plantations or under agroforestry management with food crops.

Ante el escenario económico actual, fruto de la tendencia globalizadora de los sistemas de producción y servicios, es natural la alta competencia de mercado que ha obligado a las organizaciones a implantar estrategias novedosas, dirigidas a incrementar su nivel de competitividad ante este entorno cambiante. El diseño industrial no es ajeno a esto, en la actualidad es común que las organizaciones declaren que sus productos sean fruto de escuchar al usuario. Sin embargo, este proceso se distingue por dos características que dificultan la interpretación y conversión de las necesidades del usuario en atributos de producto: la naturaleza lingüística asociada al mismo, carente de implicación directa a las propiedades deseadas del objeto, así como la dificultad para interpretar, categorizar y traducir las necesidades del usuario en especificaciones de producto. <br/>En este sentido, es notoria la falta de mecanismos sólidos y confiables para traducir las necesidades del usuario en características de diseño; no únicamente aquellas palpables, se hace un particular énfasis en la necesidad de incorporar los atributos intangibles relacionados con la percepción del producto por el usuario. Las metodologías tradicionales de diseño, basadas en el análisis de la función no resultan eficaces para anticipar estos factores y generalmente la actividad creativa se fundamenta en características del producto autodefinidas, las cuales son refinadas mediante procesos cíclicos de diseño, lo cual trae consigo un cúmulo de problemas que se traducen en ciclos de desarrollo de producto demasiado prolongados, en los cuales no existen mecanismos para prever si una combinación de características del objeto corresponden a la necesidad del usuario en un entorno de uso real.<br/>Esta genera una respuesta a la necesidad citada, mediante un mecanismo para la detección e interpretación de atributos de producto en la fase de diseño conceptual. De esta forma, no únicamente se identifican y categorizan las necesidades funcionales, sino que además se incluye un procedimiento para evaluar la percepción estética que el usuario posee hacia el objeto de diseño al examinar propuestas de diseño conceptual. <br/>Partiendo de una diferenciación inicial del tipo de requerimientos, clasificándolos según su naturaleza objetiva y subjetiva, la propuesta metodológica recurre a mecanismos particulares para la detección, interpretación y categorización de las necesidades del usuario en estas dos vertientes básicas. Estas cualidades, una vez identificadas, son incorporadas en una estructura de affordances (Gibson, 1979) que muestra el conjunto de interacciones, en las cuales las propiedades del objeto son percibidas por el usuario como posibilidades de acción. El propósito de utilizar esta distribución es el servir de guía para el equipo creativo en la fase de diseño de detalle, fungiendo como marco referencial para el diseño de forma que la actividad creativa sea dirigida anticipándose aquellos aspectos que el usuario percibe como más importantes en un producto en su entorno de uso.<br/>Para ello, se recurrió a una combinación de mecanismos adaptados para esta aplicación particular, siendo los principales de ellos el método Kano (1984), la técnica de diferenciales semánticos de Osgood (1957), el análisis factorial, así como a un sistema de inferencia que recurre a la lógica difusa o fuzzy logic (Zadeh, 1965). <br/>El resultado de la investigación se circunscribe en el ámbito de los métodos de diseño, comprendidos estos según la definición de Christopher Jones (1981), quien señala que son conjuntos de directivas a seguir durante el proceso de creación de un producto que responda a una necesidad de mercado; esta perspectiva es complementada con la visión de Cross (1996), quien interpreta los métodos de diseño como cualquier procedimiento, soporte o herramienta para diseñar, de forma que se represente el conjunto de actividades a los que el diseñador puede recurrir y/o combinar en el proceso creativo.

The last century has seen a steady increase in the extension of the average lifespan. This has concomitantly produced higher incidences of age-related chronic degenerative diseases like Alzheimer’s and Parkinson’s diseases. Age is the single greatest risk factor for the development of not just these degenerative conditions but cancer as well. The aged niche undergoes a number of maladaptive changes that allow underlying conditions to present and progress. Exactly which changes, contribute to the progression of which disease is currently an area of intense study. However, these answers often present therapeutic targets for disease prevention. Age is characterized by a progressive loss of tissue function that eventually leads to the death of the organism. At the cellular level, aged tissues are characterized by a loss of resident stem cell populations, senescence, and low-grade inflammation. While aging is heterogeneous in terms of its ultimate effect on tissue function the underlying changes have a degree of overlap. Cells often experience increased oxidative stress and a diminished activity in pathways like NRF2 whose role it is to provide resistance to such stress. Aged cells also have some change in their overall chromatin and nucleosome structure contributing to observable changes in gene expression and regulation. When these disruptions occur in tissues that can affect the larger organism such as the hypothalamus they affect the organism as a whole and contribute to syndromes seen in age such as insulin resistance. The immune system, in particular, is sensitive to both the cell-autonomous and systematic changes that occur with age. Immune and endocrine signaling pathways have a considerable amount of overlap, and mounting evidence points to the role of inflammation in the metabolic syndromes that occur with age. Immune dysfunction in the CNS has a special significance because of the dual roles of microglia. These cells exist not just to protect against foreign invasion but play vital roles in the maintenance of brain architecture and in processes central to cognition like long-term potentiation and the differentiation of stem cells in the hippocampus. The aged microglial phenotype contributes to the decline that occurs normally with age but can also be central to the progression of underlying pathologies including several degenerative diseases. Therapies targeting the maintenance of microglial function with age hold the potential to delay disease onset and possibly preserve cognitive function further into life. Top-down research approaches are well suited for the study of interactions between complex systems. The rapid improvement of mass spectrometry over the past decade has allowed researchers to examine more complex samples with fewer preparation steps and improved accuracy. This approach has thus far worked very well in the study of aging with the number of “Omics” techniques in aging models increasing rapidly. We use both label-free mass spectrometry and the more traditional real-time PCR to analyze signaling pathways and systems in both tissue homogenates and isolated cells from aged animals. By analyzing inflammatory and neurogenic pathways in animals treated with polyphenolic compounds we were able to postulate that the improved behavioral effect of these compounds is likely related to the decrease of pro-inflammatory cytokines and a restoration of WNT signaling. Proteomic analysis of aged microglia revealed widespread changes in chromatin structure and cellular machinery responsible for the regulation of transcription. In addition, we uncovered a shift in the underlying metabolic state of aged microglia and identified several pathways upstream of these changes. These upstream pathways included mTOR, a well-studied nutrient sensing pathway that plays a role in regulating microglial phenotype. Modulation of identified pathways through the use of both genetic (siRNA) and pharmacological (allosteric inhibitor) was able to recapitulate the aged phenotype in normal cells, confirming the role of these pathways in pathological changes.

Differences in permafrost conditions between the Qinghai-Xizang (Tibet) Plateau and the Mackenzie Delta region primarily relate to their Quaternary histories and their current climates. For example, the Tibetan Plateau has experienced uplift of at least 3,000 m during the last 2 million years. Under the present climatic conditions, the lower altitudinal limit of the plateau permafrost in the north is at 4,150 m a.s.l. This suggests that if the Plateau were 1,000 m lower than its present elevation, there would be no permafrost. During the Quaternary, the Tibetan Plateau remained unglaciated. This has meant that little water was available for the formation of massive ground ice, in contrast to the Mackenzie Delta region. Located at 68-69$\sp\circ$N, the Mackenzie Delta region experiences a combination of low air temperature in winter, a long solar night and a short thaw period in summer. The result is a relatively thin active layer. Located at 30-34$\sp\circ$N, the Tibetan Plateau experiences much higher solar insolation, and a diurnal temperature rhythm. The thickness of the active layer is much greater than in the Mackenzie Delta region and varies between 1.3 and 3 m or more. Permafrost on the Tibetan Plateau is much warmer and thinner than that in the Mackenzie Delta region. One consequence is that it is more sensitive to any changes in climate and surface conditions. Deep ground temperatures in the Pleistocene Mackenzie Delta indicate a recent warming trend, while a cooling trend in the Modern Delta likely relates to local factors such as channel shifting and emergence and/or sedimentation in the Mackenzie River. Water bodies are a cause of geothermal disturbances common to both regions. Numerical simulation of rapid coastal retreat in the Mackenzie Delta region indicates that subsea permafrost is at least 3$\sp\circ$C warmer than adjacent terrestrial permafrost. On the Tibetan Plateau, faulting also disturbs the geothermal regime. Measurements of in situ permafrost creep in the Fenghuo Shan area are one indicator of the warmer permafrost temperatures on the Tibetan Plateau. The average creep velocity ranges from 0.16 cm/year at 2.8 m depth to 0.54 cm/year at 1.6 m depth. These velocities are greater than those recently obtained from the High Arctic of Canada and are approximately of the order of magnitude as those obtained in the Mackenzie Valley. Inter-continental comparison of creep data suggests that climate controls the regional (large scale) magnitude of creep, and that ground ice is a local factor controlling creep rate in a particular area or site. A constitutive relationship (secondary creep power flow law) was applied to the field creep data; and creep parameters A and n were determined for each of the three different depths in the West Valley, Fenghuo Shan area, Tibetan Plateau.

Genetic variation is ubiquitous in natural populations, but very little is known about the ecological consequences of this variation. Recent interest in merging ecological and evolutionary studies has illustrated the potential for heritable trait variation to influence processes at the population, community or ecosystem level. In the few studies conducted to date, increased genetic diversity has been shown to increase the productivity and resistance to disturbance of populations of focal species and to increase the stability of plant communities. The objective of this study was to provide a test of the consequences of genetic diversity for the invasion success of populations of dandelions (Taraxacum officinale) under two sets of environmental conditions. We predicted that: (1) increasing genetic diversity in the invading population will increase average invasion success via a “selection effect”, whereby diverse populations have a higher probability of being dominated by a highly competitive genotype, or a “complementarity effect”, whereby niche differentiation or facilitation among genotypes results in mixtures having greater invasion success than expected from the performance of single genotypes; and (2) the strength of the diversity effect will be strongest in the most stressful environment. Replicate populations of three different genotypic richness levels were established in both environments (a mowed lawn and a fallow field) in June 2007. Individual plants were measured every month to determine plant size (as total leaf area) and all seed heads were counted. As predicted, plot productivity (as measured by plant leaf area or number of seeds produced) increased with plot genotypic richness, and plot productivity was greatest in the fallow field (no richness-by-environment interaction). Contrary to our second prediction, the diversity effect was strongest in the least stressful environment, the fallow field, as indicated by significant overyielding of genotype mixtures in this environment only. A positive selection effect drove the overyielding in the fallow field, while the balance of complementarity and a negative selection effect mediated the small (but non-significant) net effect in the mowed lawn. In conclusion, genetic diversity within invading populations can increase the probability of successful establishment, but the strength of this effect depends on habitat context.

This project involves two separate biomedical issues: corrosion rates of polyelectrolyte-coated magnesium (Mg) alloys, mainly used for biomedical purposes, and antibacterial properties of these alloys. Electrochemical impedance spectroscopy (EIS) was employed for analyzing these samples in order to detect their corrosion properties. In the electrochemical analysis section (GAMRY potentiostat), a corrosion rate of 72 milli inch per year was found for the sample coated with a 12 deionized phosphonic acid (Di-PA) self-assembled monolayer (SAM) and 9 chitosan/carboxymethyl cellulose (CHI/CMC) multilayers. The Mg alloy samples were coated with cationic polyelectrolyte (chitosan) and anionic polyelectrolyte (CMC) using a layer-by-layer (LBL) coating method. Both polymer solutions were 0.0015 gm. /liter. In the antibacterial test section, gentamicin was investigated for how it would adhere on the Mg substrate surface and how it would be an antibacterial agent against Escherichia coli (E. coli) bacteria. This experiment involved different sets of samples. From a coating point of view, a bare layer, self-assembly monolayer, polyelectrolyte layer, and combination of self-assembly monolayer and polyelectrolyte layer were analyzed. From an antibacterial treatment point of view, samples with no antibacterial treatment, 10% gentamicin sulfate, ultraviolet (UV) treatment and 0% gentamicin sulfate, anti-anti and 10% gentamicin sulfate, and 70% ethanol (EtOH) and 10% gentamicin sulfate were analyzed. Duration and temperature of incubation were 7 days at 35 degree C, respectively. Antibacterial sensitivity was tested using the disk diffusion method. Based on the standard diameter of the zone of inhibition chart, the antibacterial diffusion was found to be in the susceptible category, meaning that the growth of bacteria was inhibited strongly. The largest recorded diameter of the zone of inhibition was 50 mm for the pre-UV treated and gentamicin-loaded sample, which is more than three times the standard diameter.<br>Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering

Poliomyelitis as an epidemic disease passed through the Western world like some great comet. Recognised only sporadically before 1900, epidemics of polio appeared in Western communities with increasing frequency and intensity in the first half of the twentieth century. Thousands died, many more were paralysed for life. Yet by 1960 the disease was no longer feared and indeed, within a decade, was all but forgotten except by those whose lives had been directly affected. So completely had the effects of this devastating illness passed from the collective memory, that by 1980 parents had to be urged and cajoled into having their infants immunised. Little known or recognized before the twentieth century, polio has had a brief but spectacular history. It was the subject of a crusade which became “one of the greatest technical and humanistic triumphs of the age.” The story of polio is full of paradoxes. It was believed in the nineteenth century to be a recent manifestation, yet there is evidence of its appearance in antiquity. Known for many years as ‘infantile paralysis’ it was not confined to infants and was rarely paralytic. When it was paralytic, it caused the greatest morbidity and mortality amongst adults. Unlike the great scourges like typhoid, cholera or tuberculosis, epidemics of polio increased with improved hygiene and nutrition. Polio was for long considered a disease of the nervous system, but the causative agent in fact proved to be the first discovered of a huge group of entero-viruses – viruses affecting the gastro-intestinal system. Initially thought to be a rare affliction, it finally became apparent that almost all the population had suffered the disease at some time. The resultant effects of paralysis and contraction were the subject of heroic orthopaedic treatment, yet the most successful treatment was that devised by an untrained, unqualified ‘bush nurse’ from Australia. For many years an epidemic, or a threatened epidemic, could disrupt the day to day functioning of an entire country, yet it was later proved that the public health measures taken were quite ineffective. The fear it generated was partly because it was so capricious. It seemed to be the healthy and the strong who were struck down. As a noted authority wrote in 1940, “An attack of polio may be as inconsequential as measles or more agonising than death.” New Zealand was as much affected as Australia, the United States or Scandinavia. An official report recalled that “epidemic poliomyelitis was the most terrifying epidemic condition in the country and the professional and public fear was justified as no specific measure of control was known.” This study proposes to trace the history of polio in New Zealand - the course of the epidemics, its treatment, and the community's response.

Approved for public release; distribution is unlimited<br>Addressing American fear of discourse on faith, as indicated through evolving American faith narratives, is essential in effectively countering modern day terrorism and to sustaining and securing the republic founded upon unique and enduring democratic principles. This research explores American faith narratives and subsequent relevance to cosmic war, the consequences of American reactions and perceptions to religious extremism, and the prospect, parameters, and purpose of inclusive faith discourse in the public square. Reactions and realities explored herein are framed through (1) American history of faith in the public square; (2) theoretical world viewshow we know the enemy and know ourselves through Social Identity Theory and Positioning Theory, and (3) fear of unknown or uncomfortable concepts related to faith as evidenced through storylines inherent in American faith narratives. Influencing the global perception of America involves imagining the possibilities to ensure that future generations are afforded the American tradition of opportunity and freedom. This involves aggressively initiating public discourse on faith based upon securing diverse religious freedoms and beliefs and democratic principles in such a way that American faith narratives position the United States as a positive global and social influence, thereby impacting the global terrorists threat.

Thesis (MPhil (General Linguistics))--University of Stellenbosch, 2011.<br>Bibliography<br>ENGLISH ABSTRACT: Viewing cross-cultural dance performances on international tours or as part of international dance festivals has become common practice all over the world. For critique writers, choreographers/ dancers and the audience the accessibility of such a diverse variety of dance has both advantages and disadvantages. Cross-cultural differences in these performances challenge strategies of viewing and perception which may lead to aesthetic enrichment but these performances also risk being misunderstood. In dance critique writing, such a misunderstanding may result in a negative critique projecting, in a worst scenario, negative prejudices on the respective cultures. This thesis investigates how attitudes towards, and perceptions of, cultural differences are reflected in cross-cultural dance critiques, through the use of particular linguistic and stylistic devices. Analysis strategies deriving from Critical Discourse Analysis and Text Analysis are used to uncover the critique’s strategies to communicate their evaluation including ways of persuasion and power. I analyse six critiques from three countries on the performance Beautiful Me performed on international tours by the Vuyani Dance Theatre from South Africa. My initial hypothesis is that cultural differences may lead to negative critiques due to intercultural misunderstanding. Since viewing Performance Art is not only influenced by the critique writer’s cultural background but also by their perception attitude towards the performance, the analysis takes perception modes such as a theatre semiotic approach and a phenomenological approach into consideration. Interestingly, different perception modes seem to have a greater impact on the outcome of a critique than cross-cultural differences. This means that most negative evaluations must have their origin in the applied strategy of viewing and perceiving dance. The critic seems to interpret and embed the perceived features of the dance performance into specific cultural or socio-political contexts forming an individual, often complex evaluation.<br>AFRIKAANSE OPSOMMING: Om te kyk na kruiskulturele dansuitvoerings deur dansgeselskappe op internasionale toere of as deel van internasionale dansfeeste, het wêreldwyd algemene praktyk geword. Vir kritici, choreograwe/dansers en die gehoor hou die toeganklikheid van so ’n diverse verskeidenheid dans sowel voordele as nadele in. Kruiskulturele verskille in hierdie vertonings daag kyk- en waarneem-strategieë uit, wat tot estetiese verryking mag lei. Daar is egter ook ’n moontlikheid dat hierdie vertonings verkeerd geïnterpreteer mag word. Só ’n waninterpretasie in dansresensies mag lei tot negatiewe kritiek wat, in uiterste gevalle, negatiewe vooroordele oor die betrokke kulture projekteer. Hierdie tesis doen ondersoek na die wyse waarop houdings teenoor en persepsies van kultuurverskille in kruiskulturele dansresensies deur middel van spesifieke talige en stilistiese middele gereflekteer word. Analitiese strategieë uit die velde Kritiese Diskoersanalise en Teksanalise word gebruik om kritici se strategieë wat ’n oordeel kommunikeer, bloot te lê. Ek analiseer ses resensies uit drie lande wat handel oor die vertoning Beautiful Me wat deur die Suid-Afrikaanse dansgeselskap Vuyani Dance Theatre tydens internasionale toere opgevoer is. My aanvanklike hipotese is dat kultuurverskille aanleiding mag gee tot negatiewe kritiek vanweë interkulturele misverstande. Aangesien die beoordeling van Uitvoerende Kunste nie slegs deur die kritikus se kulturele agtergrond beïnvloed word nie, maar ook deur hul waarnemingshouding teenoor die vertoning, neem die analise waarnemingsmodusse soos ’n teater-semiotiek-benadering en ’n fenomenologiese benadering in ag. Interessant genoeg, lyk dit asof verskillende waarnemingsmodusse ’n groter impak het op die uitkoms van kritiek as kruiskulturele verskille. Dít beteken dat die meeste negatiewe oordele hul oorsprong moet hê in die toegepaste strategie van dans kyk en waarneem. Dit blyk dat die kritikus die waargenome eienskappe van die dansuitvoering interpreteer en inbed in spesifieke kulturele of sosio-politiese kontekste wat aanleiding gee tot die verskillende, dikwels komplekse maniere van beoordeling.

Cette thèse décrit l’incorporation de fer dans l’hétérostructure InGaAsP/InP par implantation ionique à haute énergie (MeV) suivi d’un recuit thermique rapide. L’alliage quaternaire InGaAsP est tout indiqué pour fabriquer des couches photoconductrices qui peuvent absorber dans le proche-infrarouge, à 1.3 µm ou 1.55 µm. Ce procédé vise à développer de nouveaux matériaux de forte résistivité pour l’holographie photoréfractive et la spectroscopie térahertz pulsée. À notre connaissance, cette investigation représente les premiers essais détaillés de l’implantation de fer dans le matériau InGaAsP/InP. Les principaux paramètres de fabrication, tels la fluence d’ions de fer, la température d’implantation et la température de recuit ont été explorés. Les propriétés physiques des matériaux produits ont été étudiées avec des mesures électriques (résistivité et effet Hall avec l’analyse de Van der Pauw), optiques (photoluminescence, absorption et réflectivité différentielle résolue en temps) et structurales (diffraction de rayons X, canalisation de la rétrodiffusion Rutherford et microscopie électronique en transmission). Pour fabriquer des couches à forte résistivité pour des applications holographiques à 1.3 µm, nos résultats ont montré qu’il est préférable d’éviter l’amorce de l’amorphisation lors de l’implantation du quaternaire pour maintenir une bonne qualité cristalline après recuit. Ceci favoriserait une compensation par l’activation du fer comme impureté profonde. Une résistivité de l’ordre de 10[indice supérieur 4] Ωcm est mesurée après recuit. Pour fabriquer des couches à forte résistivité pour des applications de spectroscopie térahertz pulsée à 1.55 µm, nous privilégions l’amorphisation par implantation froide et la recristallisation, ce qui réduit le temps de recombinaison des photoporteurs sous la picoseconde. L’émission d’ondes térahertz par ce matériau est démontrée sur une largeur de bande de 2 THz. L’évidence expérimentale montre la formation d’une microstructure polycrystalline dans la couche d’InGaAsP, ayant une forte densité de fautes planaires et une taille de grains nanométrique qui varient avec la température de recuit, ce qui suggère une connexion avec les propriétés optoélectroniques du matériau.

O presente relatório de estágio desenvolveu-se no âmbito da unidade curricular de prática de ensino supervisionada, tendo por finalidade a obtenção do grau de mestre em educação pré-escolar. Corresponde à descrição de um trabalho desenvolvido num contexto de jardim-de-infância inserido no meio urbano, com um grupo de crianças de três, quatro e cinco anos de idade. Este trabalho procurou compreender de que forma o conhecimento do meio físico e social envolvente podia propiciar a construção de novos conhecimentos em crianças em idade pré-escolar, analisando também se a parceria entre a instituição pré-escolar e a família poderia contribuir para uma aprendizagem mais significativa. Neste sentido, construímos um quadro teórico em que procurámos aprofundar saberes ao nível dos processos de aprendizagem e desenvolvimento das crianças e a importância que pode assumir a cooperação entre família e a instituição pré-escolar nesse processo, orientando-nos por uma perspectiva socioconstrutivista. Foi sustentado na metodologia de investigação-acção, levando assim à utilização de diversas técnicas e instrumentos para recolher dados para ser possível responder às questões delineadas e atingir os objectivos propostos. Procurámos promover experiências de aprendizagem partindo da exploração do meio em que estamos inseridos, integrando-as com todas as outras áreas e domínios evidenciadas nas Orientações Curriculares para a Educação Pré-Escolar. Os resultados que emergiram deste trabalho demonstram que o meio em que estamos inseridos possibilita a realização de aprendizagens múltiplas e que a parceria entre a família e a instituição pré-escolar assume-se como uma mais-valia na educação das crianças. This stage report was developed in the course of supervised teaching practice, which aims to obtain the master's degree in pre-school education. It corresponds to a description of work done in the context of a kindergarten housed in a urban environment and which has children aged three, four and five years old. This work tried to understand how the environment knowledge could be favorable for the construction of pre-school children‟s new knowledge, and also examine whether the partnership between the pre-school institution and family could contribute to more significant learning. In this sense, we build a theoretical framework in which we sought to deepen the knowledge level of learning processes, children‟s development and the importance of cooperation that the family and pre-school institution may take in the process, guiding us through a social and constructivist perspective. It was held in the methodology of research and action which leads to the use of various techniques and instruments in order to collect data and to be able to respond to the outlined questions and also to achieve all proposed objectives. We have tried to promote the achievement of learning experiences starting from the exploitation of the environment where we are and also integrating them with all the other areas and domains highlighted in the curriculum guidelines for Pre-school Education. The results that emerged from this work show us that this environment gives us multiple learning and that the partnership between the family and pre-school institution is an add-value for child education.

Desarrolla un método cuantitativo por HPLC para la determinación de Ácido Fenilglioxílico (PGA) y Ácido Mandélico (MA), biomarcador para determinar la exposición a estireno; post ensayos preliminares, se optimizó el mismo. Las condiciones cromatográficas son columna C18 x 4,6 mm x 150 mm (5 µm); flujo 0,8 mL/min; volumen de inyección 5 µL; fase móvil buffer K2HPO4 10 mM pH 2,8: Acetonitrilo (90:10); longitud de onda: 254 nm; temperatura 30 °C. La veracidad del método para el análisis de PGA en orina se determinó con Bio-rad (MRC: muestra de referencia certificada). Los resultados de PGA fueron 45,407 mg/L (Bio-Rad Nivel 1) y 218,085 mg/L (Bio-Rad Nivel 2). Se aplicó la t-Student en los datos señalados, cuyos resultados no se diferenciaron significativamente al valor de la MRC. Se usó la recuperación para determinación de la veracidad de MA. El promedio de las recuperaciones en el Nivel 1 (99,9827) y en el Nivel 2 (99,9727) no presentó diferencia significativa con respecto al valor teórico (recuperación 100 %).<br>Tesis

Made available in DSpace on 2014-09-30T02:01:30Z (GMT). No. of bitstreams: 1 000461635-Texto+Completo-0.pdf: 936336 bytes, checksum: 58f7dc0a52012169e932586ff40e755f (MD5) Previous issue date: 2014<br>This Master thesis consists of two studies presented through articles formats. One article has a theoretical nature and the other refers to an empirical study. The overall objective of this study was to understand the sexuality process and its vicissitudes in consecrated religious life choice of young women. The theoretical paper presents a non systematic literature review discussing theoretical concepts about sexuality and its vicissitudes through consecrated religious life choice. The empirical article is an exploratory cross-sectional qualitative research, which aimed to investigate the sexuality process and its vicissitudes in religious life of young people who choose to follow the consecrated religious pathway and impasses that underlie this choice. Therefore, semi-structured interviews were carried out considering the topics: sexuality meaning for religious; experience of sexuality within the family - life story; being a woman-a woman in the consecrated religious life; experiences of caring relationships; impasses in sexual experience among religious; vocation - religious vocation; motivations for choosing and staying in the consecrated religious life.From the content of the reports it was found that the choice of sexuality in religious life is not for the young among the greatest challenges . However sexuality expressed in feelings and attitudes in fraternal relations of everyday life these young people the crossing underlies this phenomenon which reveals difficulties of sexuality lived in its broad sense. Conflicts are observed though their speech, therefore another signification in what refers to religious life and sexuality is also observed. Women interviewed pointed as a significant challenge that comes through religious life the difficulty in fraternal relations.<br>Esta dissertação é composta de dois estudos apresentados na forma de artigos. Um dos artigos é de caráter teórico e o outro é um artigo empírico. O objetivo geral do trabalho foi compreender o processo de sexualidade e suas vicissitudes na escolha de vida religiosa consagrada em mulheres jovens. O artigo teórico apresenta uma revisão assistemática da literatura que objetivou discutir, a partir de teóricos, acerca da sexualidade e suas vicissitudes no cenário da vida religiosa consagrada. O artigo empírico caracterizou-se como uma pesquisa qualitativa, transversal, exploratória cujo objetivo foi investigar o processo de sexualidade e suas vicissitudes na vida das jovens religiosas que fizeram a escolha pela vida religiosa consagrada e quais impasses subjazem a esta escolha. Para tanto, foram realizadas entrevistas semi-estruturadas, considerando os seguintes tópicos: significado da sexualidade para as religiosas; vivência da sexualidade no contexto familiar – história de vida; ser mulher- ser mulher na vida religiosa consagrada; experiências de relacionamentos afetivos; impasses na vivência da sexualidade entre as religiosas; vocação – vocação religiosa; motivações para escolha e permanência na vida religiosa consagrada.A partir do conteúdo dos relatos constatou-se que a sexualidade na escolha de vida religiosa não se constitui, para as jovens, entre os maiores desafios. Porém, a sexualidade expressa em sentimentos e atitudes nas relações fraternas do cotidiano dessas jovens, subjaz o atravessamento desse fenômeno que revela dificuldades da sexualidade vivida no seu sentido amplo. As falas demonstram conflitos, mas também ressignificação por parte destas jovens mulheres no que se refere à vida religiosa e à sexualidade. Entretanto, foi predominante nas falas das religiosas que um significativo desafio que circunscreve e atravessa a escolha de vida religiosa consagrada é a dificuldade das relações fraternas.

Work and family are the two most significant life domains for most individuals (Greenhaus, Collins & Shaw, 2003). Compositional and structural changes in the work and family domains over the past few decades such as: dual-earner couples and single working parents, the decline of traditional gender roles and a movement toward egalitarian family structures have rendered increased understanding and reconciliation of family and working life (Steil, 2007). Such work- family considerations, however, are not only important for adults within the workforce, but also for young adults who are in the process of making future family and career decisions, and are about to enter the workforce (Westring & Ryan, 2011). The purpose of this study was to explore how students understand and distinguish between different life roles, and therefore gain insight into the expectations they have of their future life roles. Using Kelly's Repertory Grids Technique, qualitative data was obtained through fifteen interviews with postgraduate students from the University of Cape Town. The data was analysed using a combination of thematic analysis and frequency counts. The reliability of the results was ensured by conducting two sets of reliability checks. Following thematic analysis, eight dyadic themes emerged: self-interest- selflessness, demanding- relaxing, collaborationindependence, freedom-restriction, affective- unaffective, boring- enjoyment, structuredflexible, and personal satisfaction- obligation. These themes revealed values and attributes students perceive as significant in the construal of their future life roles. The results were interpreted and discussed in light of existing research and literature in the field.

Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 24, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dissertation advisor: Dr. Cynthia MacGregor. Vita. Includes bibliographical references.

Recently an iterative method was formulated employing a new splitting strategy for the solution of tridiagonal systems of difference equations. The method was successful in solving the systems of equations arising from one dimensional initial boundary value problems, and a theoretical analysis for proving the convergence of the method for systems whose constituent matrices are positive definite was presented by Evans and Sahimi [22]. The method was known as the Alternating Group Explicit (AGE) method and is referred to as AGE-1D. The explicit nature of the method meant that its implementation on parallel machines can be very promising. The method was also extended to solve systems arising from two and three dimensional initial-boundary value problems, but the AGE-2D and AGE-3D algorithms proved to be too demanding in computational cost which largely reduces the advantages of its parallel nature. In this thesis, further theoretical analyses and experimental studies are pursued to establish the convergence and suitability of the AGE-1D method to a wider class of systems arising from univariate and multivariate differential equations with symmetric and non symmetric difference operators. Also the possibility of a Chebyshev acceleration of the AGE-1D algorithm is considered. For two and three dimensional problems it is proposed to couple the use of the AGE-1D algorithm with an ADI scheme or an ADI iterative method in what is called the Explicit Alternating Direction (EAD) method. It is then shown through experimental results that the EAD method retains the parallel features of the AGE method and moreover leads to savings of up to 83 % in the computational cost for solving some of the model problems. The thesis also includes applications of the AGE-1D algorithm and the EAD method to solve some problems of fluid dynamics such as the linearized Shallow Water equations, and the Navier Stokes' equations for the flow in an idealized one dimensional Planetary Boundary Layer. The thesis terminates with conclusions and suggestions for further work together with a comprehensive bibliography and an appendix containing some selected programs.

Using the internet to meet dating partners is increasingly popular and may have ramifications that are not yet fully realized. Although many dating sites have been operating for years, new online dating platforms continue to draw millions of new users. By using a large sample of people who use online dating platforms (n=1,286) we identified similarities and differences in what motivates people to use geosocial apps and dating sites. Motivations previously considered in the literature were supported and brought together in a single theory driven confirmatory factor analysis for each type of dating platform. A motivation to seek amusement was a latent factor unique to geosocial app use. Implications for researchers, clinicians, and dating platform users and developers may include helping users be better matched to others who have similar motivations to improve the online dating experience.

>Magister Scientiae - MSc<br>It is well known, that there is a severe lack of information available pertaining to neutron rich nuclei, specifically of those nuclei with mass numbers ≥ 60. These neutron rich nuclei are not easy to access in current experimental facilities or be produced with sufficient yield to allow for it to be studied. In order to expand our understanding of nuclear physics by studying the properties and characteristics of these nuclei, the development of new facilities producing Radioactive-ion Beams (RIBs) is required. The applications for RIBs are wide, allowing for deeper investigations into the properties of nuclei, their interactions and the manner in which they were formed in the early universe. Additionally, there are various interdisciplinary fields such as medicine, biology and material science in which RIBs can be utilized as a driving mechanism for new research and technological innovation. The iThemba Laboratory for Accelerator Based Sciences (iThemba LABS), South Africa, has proposed a new facility for the production and acceleration of radioactive-ion beams (RIBs). The RIB Project is to be developed in sequential phases and would produce a range of neutron-rich isotopes for low-energy materials science and nuclear physics research. Of specific interest, is the production of the Helium-6 isotope (6He), for its potential applications in various areas of nuclear physics research. The aim of this research work was to design, model and optimise a RIB production target capable of producing high intensity 6He beams, guided by the characteristics of the primary proton beam available for use at iThemba LABS. This research work/design study is however limited, due to the absence of experimentally measured and verified 6He cross section data for proton induced reactions on the proposed target materials (Graphite and Boron Carbide). However, best-estimate approaches were adopted through the use of validated computer codes. Additionally, all 6He yield results are presented as in-target yields, as this study did not cover the diffusion (isotope release) efficiency of the target systems in question. Three RIB production targets types were investigated using Graphite, Boron Carbide and Beryllium Oxide as potential target materials. Following numerous optimisation processes, a Boron Carbide RIB target was converged upon, proving to be suitable for the production of high intensity 6He beams at iThemba LABS, by meeting the material thermal and mechanical limiting criteria for operation. This target system was found to produce an in-target 6He yield rate of 2 ~ 3 x 1011 6He/s, considered sufficient for experimental application at iThemba LABS.

As primary care providers in correctional facilities, correctional nurses are expected to balance inmates' healthcare needs with the security demands of the facility. This project explored whether an evidence-based education program could provide strategies for promoting health, a healthy work environment, and a sense of well-being to improve the knowledge, coping skills, and well-being of nurses working in a correctional occupational setting. Twenty nurses participated in an educational intervention project that was guided by the transactional theory of stress. Using a pretest/posttest design, data were collected over a 2-week period and calculated using means and percentages. The descriptive statistics using the 6 items in the pre- and posttest showed an average gain of 48% in knowledge compared to the pretest scores. Using the World Health Organization Well-Being Index scale, participants' sense of well-being also improved with an average score of 21% to 40% following the intervention. Findings indicate that effective management of work-related stress could result in positive social change by improving the health of nurses, the health outcomes of inmates, their families, and the community at large. With knowledge from this project, leadership might provide support and create opportunities for nurses to improve their skills.

Damage to the ventromedial prefrontal cortex (vmPFC) can lead to disturbances in personality, emotional dysregulation, impairments in social conduct, and difficulties in decision-making. Many researchers have likened the conduct of individuals with vmPFC lesions to that of criminal psychopaths, labeling the effects of vmPFC damage “pseudopsychopathy” or “acquired sociopathy.” However, although psychopathy—a condition marked by a distinct mosaic of antisocial personality traits and behaviors—has been studied and characterized as a psychological and behavioral disorder by many researchers, the overlap between acquired sociopathy and psychopathy remains ambiguous. This study assessed the severity of psychopathic personality traits in neurological patients with acquired damage to the vmPFC using both informant-report and self-report measures. On both informant-report and self-report measures, individuals with vmPFC damage showed no significant elevations across a wide range of psychopathic traits relative to demographically-matched neurologically healthy comparison participants and patients with damage outside of the vmPFC. The results showed only one trait, Fearlessness, that was significantly higher in patients with vmPFC lesions relative to the neurologically-healthy comparison group.