This dissertation investigates the extent and type of influence the Shona folktale has had on the writing of the Shona novel. Of particular interest is how much influence the folktale has had on the early writers of Shona novels as compared to the modern writers. The study investigates folktale influence on the development of plot, setting and characterisation in targeted novels. With regard to the development of plot, the study focuses on folktale influence on the following aspects; the exposition, complication, climax and resolution. Looking at setting, the study investigates folktale influence on setting as place, time or social circumstances in which the stories happen. The study also investigates the type of characters the novelists portray and seek to detect any folktale influence on characterisation. / African Languages and Literature / Thesis (M.A.)

Dans cette thèse, des mousses produites à plus de 90% à partir de produits naturels et à très faible conductivité thermique ont été étudiées en détail. L’objectif principal de ce travail était d’améliorer certaines faiblesses de ces matériaux et de résoudre les problèmes qui pourraient être rencontrés lors de leur utilisation, pour leur permettre de concurrencer d’autres mousses synthétiques actuellement sur le marché de l’isolation thermique. De nouvelles méthodologies ont été proposées pour optimiser les mousses à base de tanin de différents points de vue. Tout d’abord, des mousses liquides ont été analysées en termes de stabilité et de processus de polymérisation à l’aide d’un analyseur de lumière rétrodiffusée, afin de les transformer en mousses rigides de tanin plus performantes. Des plans d’expériences ont également été utilisés pour améliorer les propriétés mécaniques de mousses rigides, produites par moussage physique, sans porter préjudice à leur conductivité thermique. D’autre part, des traitements d’hydrophobisation ont été réalisés pour réduire la sensibilité de ces mousses à l’eau, qu’elle soit sous forme liquide ou vapeur, et l’effet des ingrédients des formulations sur leurs propriétés au feu a été élucidé. Enfin, deux techniques de caractérisation mécanique ont été étudiées et comparées, ce qui a permis de déterminer le coefficient de Poisson et le facteur de perte, et de mettre en évidence les précautions à prendre pour caractériser les mousses fragiles / In this thesis, foams based on more than 90% of natural products and with an exceptionally low thermal conductivity have been studied in depth. The main objective of this work was to improve some of the weaknesses of those materials and to solve problems that might be encountered during use, for allowing them to compete with other synthetic foams that are currently on the thermal insulation market. New methodologies have been proposed to optimise tannin-based foams from different points of view. First, liquid foams were analysed in terms of stability and polymerisation process using a backscattered light analyser, in order to convert them into improved rigid tannin-based foams. Experimental design was also used to improve the mechanical properties of physically blown rigid foams without prejudicing their thermal conductivity. On the other hand, hydrophobisation treatments were suggested for reducing the sensitivity of those foams to water in liquid or vapour form, and the effect of formulations’ ingredients on their fire properties were elucidated. Finally, two techniques of mechanical characterisation were investigated and compared, leading to Poisson’s coefficient and loss factor, and evidencing the precautions to be taken for characterising brittle foams

Regenerative medicine and cell therapies hold great potential to treat a variety of medical conditions. Product characterisation of these therapies is particularly difficult as they pose regulatory challenges due to donor heterogeneity and the lack of standardised lot release tests that can reliably predict in vivo function. Human mesenchymal stem cells (hMSCs), also called multipotent stem cells or mesenchymal stromal cells, are a viable option in cell therapies due to their immunosuppressive and pro-angiogenic functions. Currently there are no standardised methods or potency assays to quantify these properties. To address this, five individual hMSCs lines from different donors were created and characterised based upon growth rate, differentiation capability and extracellular surface protein expression. A novel multiparameter flow cytometry method to characterise the cells based upon extracellular surface markers was developed that supports high-throughput and high-content analyses. Three candidate lines were taken forward and assessed in multiple in vitro bioassays that examined the hMSC immunosuppressive response to a defined inflammatory environment, effect on T-cell proliferation, and effect on a mixed lymphocyte population. Next, the angiogenic properties were assessed using human umbilical vein endothelial cells (HUVECs) tube formation as a model for cardiac regeneration. This involved utilising automated time lapse microscopy techniques coupled with image analysis software to quantify endothelial to tube formation. Further analysis of the hMSC secretome revealed differences in the levels of pro-angiogenic cytokines such as vascular endothelial growth factor, hepatocyte growth factor and IL-8. Significant differences in angiogenic potency were found between the hMSC lines. This thesis highlights the need to develop specific assays that reflect the intended clinical action. Taken together, these quantitative approaches provide valuable tools to measure hMSC quality and potency, and supports continued efforts to improve characterisation strategies for cellular therapies.

In this study the practical work with the EU Water Framework starts on the island of Gotland. 33 lakes and 32 streams have been characterized and classified regarding to their ecological status. The aim with the characterisation is to create a uniform discription of all waterbodies and a comparable estimation for the future. The aim with the classification is both to study the waterbodies ecological status and to gain knowledge of where the resources should be concentrated so that the ecological status in all waterbodies will be good in 2015. The characterisation has been done according to the EU Water Framework Directive, and the factors that have been applied are the mean depth and area of the lake. The length and size on the catchment area are the factors that have been used on streams. The classification is issued from biological, chemical and hydromorphological elements. The biological elements in both lakes and streams are fish and benthic macroinvertebrates. The chemical elements in lakes consist of total phosphorus, total nitrogen, quotient total nitrogen/total phosphorus, chemical oxygen demand, alkalinity and pH-value. The chemical elements in streams consist of area-specific losses of total phosphorus and total nitrogen, chemical oxygen demand, alkalinity and pH-value. The hydromorphological elements are lakes that are regulated, streams that have been straightened out and streams that have something stopping sawing fish. The result of the characterisation shows five different sea types: large and deep seas, meanlarge and deep seas, meanlarge and shallow seas, small and deep seas as well as small and shallow seas. The result from the classification shows that 26 lakes have high or good ecological status. However, this still means that the seven lakes Asträsk, Bogeviken, Bondansträsk, Fridträsk, Inre Stockviken, Mjölhatteträsk and Paviken have moderate ecological status. 15 streams have good or high ecological status, while nine have moderate status. These nine streams are Burgsvikenån, Gothemsån, Ireån, Halorån, Lummelundaån, Närkån, Snoderån, Vägumeån as well as Västergarnsån. The ecological status could not be decided in eight streams, due to the low number of facts. All lakes and streams with moderate ecological status, except Bondansträsk, have recieved this estimation as a result of the high substance of nutrients. While fish in Bondansträsk is not good, the lake recieved the estimation moderate status. / I detta examensarbete inleds det praktiska arbetet med ramdirektivet för vatten på Gotland. I enlighet med vattendirektivet har 33 gotländska sjöar och 32 gotländska vattendrag karakteriserats och klassificerats utifrån ekologisk status. Syftet med karakteriseringen är att skapa en enhetlig beskrivning av samtliga vattenförekomster, vilket ger ett jämförbart underlag inför fortsatta bedömningar av sjöar och vattendrag på Gotland. Syftet med klassificeringen är att dels ta reda på den ekologiska statusen för gotländska ytvatten, dels att få kunskap om var resurserna bör läggas för att en god ekologisk status skall uppnås till år 2015. Karakteriseringen utfördes enligt vattendirektivets system B, och de faktorer som användes är maxdjup och sjöarea för sjöar samt längd och avrinningsområdets area för vattendrag. Detta resulterade i fem sjötyper: stora och djupa sjöar, stora och grunda sjöar, mellanstora och grunda sjöar, små och djupa sjöar samt små och grunda sjöar. Vattendragen indelades i fyra typer: långa vattendrag med stort avrinningsområde, långa vattendrag med mellanstort avrinningsområde, korta vattendrag med mellanstort avrinningsområde samt korta vattendrag med litet avrinningsområde. Klassningen utgick, i enlighet med vattendirektivet, från biologiska, kemiska och hydromorfologiska faktorer. Den biologiska klassningen i både sjöar och vattendrag gjordes med utgångspunkt från fisk och bottenfauna. Den kemiska bedömningen i sjöar gjordes utifrån totalfosfor, totalkväve, fosfor/kväve-kvot, kemisk syreförbrukning, alkalinitet och pH-värde. För vattendrag har arealspecifik förlust av fosfor och kväve, kemisk syreförbrukning, alkalinitet och pH-värde använts. Den hydromorfologiska bedömningen gjordes med hänsyn tagen till rätning av vattendrag, vandringshinder i vattendrag samt reglering av sjöar. Resultatet av klassificeringen visar att hela 26 av de 33 undersökta gotländska sjöarna har hög eller god ekologisk status, och sju sjöar, Asträsk, Bogeviken, Bondansträsk, Fridträsk, Inre Stockviken, Mjölhatteträsk och Paviken, har måttlig ekologisk status. 15 av de 32 undersökta vattendragen har hög eller god ekologisk status, medan nio vattendrag, Burgsvikenån, Gothemsån, Ireån, Halorån, Lummelundaån, Närkån, Snoderån, Vägumeån samt Västergarnsån, har måttlig ekologisk status. Vidare har ekologisk status inte kunnat bestämmas för åtta vattendrag, då inte tillräckligt med data funnits för att kunna genomföra en rättvis bedömning. Samtliga sjöar och vattendrag som har måttlig ekologisk status, förutom Bondansträsk, har erhållit denna bedömning på grund av alltför höga halter respektive transporter av näringsämnena kväve och fosfor. Bondansträsk har fått detta omdöme eftersom tillstånd och avvikelse från jämförvärde för fisk inte är helt bra.

Made available in DSpace on 2015-04-11T13:54:25Z (GMT). No. of bitstreams: 1 jessyca dos reis.pdf: 2629785 bytes, checksum: 664a61966469b33065e128fef56d7900 (MD5) Previous issue date: 2013-10-29 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Environmental isolates of filamentous fungi are widely studied for their ability to secrete metabolites of great commercial value, including pigments. These, in turn, find application to color textile raw materials, foods and medicines. In this context, the aim of this work was to select fungi from soil samples Amazon with potential for the production of pigments. For this, samples were collected from surface soil and colonies were isolated by serial dilution technique. The macro and microscopic characteristics of colonies grown within 72 hours were used for determining the gender of the isolates and the ITS region of the ribosomal DNA of fungal pigment producers was sequenced for identification to the species level. A cryopreservation technique and conservation at -70 C was employed to preserve the lines with biotechnological potential. A bioprocess performed in broth Czapeck enabled the selection of fungi which produce colored compounds. Fractions containing the pigments were extracted by use of solvents of different polarity and selection of the pigment of interest was due to the color intensity of the substance present in the fractions. The techniques used for the isolation and structural elucidation of the sample of interest involved chromatographic fractioning (Sephadex LH-20 column and microcrystalline cellulose column), recrystalization and NMR (Nuclear Magnetic Resonance). The influence of carbon sources and nitrogen on the yield of the isolated substance was also studied in this work. From samples collected was possible to isolate 50 soil fungi. Of these five strains were able to produce pigments during fermentation. Producing fungi were identified as Penicillium sclerotiorum 2AV2, Penicillium sclerotiorum 2AV6, Aspergillus calidoustus 4BV13, Penicillium citrinum 2AV18 e Penicillium purpurogenum 2BV41. Penicillium sclerotiorum 2AV2 produced fractions very colorful and was chosen to continue the activities of the chemical characterisation. After isolation of the substance was obtained as a yellow-orange powder, which was identified by NMR as sclerotiorin, a major metabolite that has not been previously described by synthesis by fungi from the Amazon. The influence of carbon and nitrogen sources for production of sclerotiorin was analised and it was found that rhamnose and peptone increased yield when used separately. These results indicate that Amazonian fungi bioprospecting is an alternative to search for new sources of natural dyes, since it allows to exploit the biotechnological potential of our region while allowing knowledge of species of microorganisms producers. / Isolados ambientais de fungos filamentosos são amplamente estudados por sua capacidade de secretar metabólitos de grande valor comercial, entre eles os pigmentos. Estes, por sua vez, encontram aplicação como corantes de matérias-primas têxteis, alimentos e medicamentos. Nesse contexto, o objetivo deste trabalho foi selecionar fungos de amostras de solo Amazônico com potencial para a produção de pigmentos. Para isso, foram coletadas amostras de solo superficial e colônias foram isoladas pela técnica da diluição em série. As características macro e microscópicas das colônias crescidas em até 72 horas foram utilizadas para a determinação do gênero dos isolados e a região ITS do DNA ribossomal dos fungos produtores de pigmentos foi sequenciada para permitir a identificação em nível de espécie. Para conservar as linhagens com potencial biotecnológico foi empregada uma técnica de criopreservação e armazenamento a -70 C. Um bioprocesso realizado em caldo Czapeck possibilitou a seleção dos fungos produtores de compostos coloridos. Frações contendo os pigmentos foram extraídas pelo uso de solventes de diferentes polaridades e o pigmento de interesse foi selecionado pela intensidade da cor da substância presente nas frações. A metodologia para isolamento e caracterização química da amostra envolveu técnicas de fracionamento cromatográfico (coluna Sephadex LH-20 e coluna de celulose microcristalina), recristalização e análises de RMN (Ressonância magnética nuclear). A influência das fontes de carbono e nitrogênio sobre o rendimento da substância isolada também foi estudada nesse trabalho. A partir das amostras coletadas foi possível isolar 50 fungos do solo. Desses, 5 cepas foram capazes de produzir pigmentos durante a fermentação. Os fungos produtores foram identificados como Penicillium sclerotiorum 2AV2, Penicillium sclerotiorum 2AV6, Aspergillus calidoustus 4BV13, Penicillium citrinum 2AV18 e Penicillium purpurogenum 2BV41. Penicillium sclerotiorum 2AV2 produziu frações muito coloridas e foi escolhido para prosseguir as atividades de caracterização química. Após o isolamento da substância, obteve-se um pó amarelo-alaranjado, que foi identificado por RMN como esclerotiorina, um importante metabólito que ainda não havia sido descrito pela síntese por fungos da Amazônia. A influência das fontes de carbono e nitrogênio para a produção de esclerotiorina foi analisada, e verificou-se que ramnose e peptona aumentaram o rendimento quando utilizadas separadamente. Estes resultados indicam que a bioprospecção de fungos Amazônicos é uma alternativa para a pesquisa por novas fontes de corantes naturais, pois permite explorar o potencial biotecnológico da nossa região, ao mesmo tempo em que possibilita o conhecimento das espécies de micro-organismos produtores.

O filtro cuno faz parte do circuito de tratamento de água do reator IEA-R1 que , quando saturado, é substituído, se tornando um rejeito radioativo que deve ser gerenciado. Neste trabalho foi realizada a caracterização primária do filtro cuno do reator nuclear IEA-R1 do IPEN utilizando-se espectrometria gama associada ao método de Monte Carlo. A espectrometria gama foi realizada utilizando-se um detector de germânio hiperpuro (HPGe). O cristal de germânio representa o volume ativo de detecção do detector HPGe, que possui uma região denominada camada morta ou camada inativa. Na literatura tem sido reportada uma diferença entre os valores experimentais e teóricos na obtenção da curva de eficiência desses detectores. Neste trabalho foi utilizado o código MCNP-4C para a obtenção da calibração em eficiência do detector para a geometria do filtro cuno, onde foram estudadas as influências da camada morta e do efeito de soma em cascata no detector HPGe. As correções dos valores de camada morta foram realizadas variando-se a espessura e o raio do cristal de germânio. O detector possui 75,83 cm3 de volume ativo de detecção, segundo informações fornecidas pelo fabricante. Entretanto os resultados encontrados mostraram que o valor de volume ativo real é menor do que o especificado, onde a camada morta representa 16% do volume total do cristal. A análise do filtro cuno por meio da espectrometria gama, permitiu a identificação de picos de energia. Por meio desses picos foram identificados três radionuclídeos no filtro: 108mAg, 110mAg e 60Co. A partir da calibração em eficiência obtida pelo método de Monte Carlo, o valor de atividade estimado para esses radionuclídeos está na ordem de MBq. / The Cuno filter is part of the water processing circuit of the IEA-R1 reactor and, when saturated, it is replaced and becomes a radioactive waste, which must be managed. In this work, the primary characterization of the Cuno filter of the IEA-R1 nuclear reactor at IPEN was carried out using gamma spectrometry associated with the Monte Carlo method. The gamma spectrometry was performed using a hyperpure germanium detector (HPGe). The germanium crystal represents the detection active volume of the HPGe detector, which has a region called dead layer or inactive layer. It has been reported in the literature a difference between the theoretical and experimental values when obtaining the efficiency curve of these detectors. In this study we used the MCNP-4C code to obtain the detector calibration efficiency for the geometry of the Cuno filter, and the influence of the dead layer and the effect of sum in cascade at the HPGe detector were studied. The correction of the dead layer values were made by varying the thickness and the radius of the germanium crystal. The detector has 75.83 cm3 of active volume of detection, according to information provided by the manufacturer. Nevertheless, the results showed that the actual value of active volume is less than the one specified, where the dead layer represents 16% of the total volume of the crystal. A Cuno filter analysis by gamma spectrometry has enabled identifying energy peaks. Using these peaks, three radionuclides were identified in the filter: 108mAg, 110mAg and 60Co. From the calibration efficiency obtained by the Monte Carlo method, the value of activity estimated for these radionuclides is in the order of MBq.

This work studies guided wave propagation in pipes coated with thick highly viscoelastic coating materials. The main motivation for this study is the problems associated with Long Range Ultrasonic Testing (LRUT) of coated pipelines. The results reported in the literature show that the proper determination of the optimum LRUT parameters depends strongly on the bulk acoustic properties of the coating materials. The bulk acoustic properties of coating materials reported in the literature show that they could vary significantly depending on the coating material age, temperature and bonding level. The methods for acoustic characterisation of coating materials reported by other researchers, have been studied and it was found that they do not take into account the temperature changes and bonding level variation. In this work, the bulk acoustic properties of two highly viscoelastic bitumen based coating materials are investigated. The conventional methods for acoustic characterisation are studied and a new method for independent measurement of bulk shear properties of bitumen is developed. The bulk acoustic properties of bitumen based coating materials are also studied by two new characterisation methods. The first method derives the bulk coating material properties from experimental data on guided wave reflection coefficients. The second method derives the coating material bulk properties from experimentally measured guided wave attenuation data. It is demonstrated that these new methods deliver much more accurate values for the bulk acoustic properties when compared to the data measured by conventional methods. The second method is used to study the temperature effect on the bulk acoustic properties and it is demonstrated that temperature has a significant effect. The validity of the acoustic properties for the two bitumen materials is investigated through comparison between numerical predictions and experimental data measured for guided wave reflection coefficients and attenuation of the torsional T(0,1) and longitudinal L(0,2) guided wave modes. Good agreement is achieved in the frequency range between 20 kHz and 100 kHz, which is typical for LRUT of pipes.

This essay uses corpus linguistic methods to study aspects of the novel Vanity Fair by W M Thackeray. The aim is to study the way Thackeray chose to describe his two female protagonists, Rebecca Sharp and Amelia Sedley. This is accomplished by a closer study of keywords in Vanity Fair, created by using a reference corpus consisting of thirteen novels by Victorian authors. These keywords are used to define semantic fields related to the novel. Keywords from the semantic field closest to the protagonists are studied in context. In addition, adjectives that collocate with the names of the protagonists are analyzed to compare the characterization of each woman. The study indicates that Thackeray has used fewer adjectives to describe Amelia than Rebecca, but that he has used these more frequently, which may cause readers to form a stronger mental picture of Amelia’s character sooner than they do for Rebecca’s.

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