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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Analyse des interactions entre les racines d'hévéa (Hevea brasiliensis Muel. Arg.) et de cultures intercalaires dans les jeunes plantations du Nord-Est de la Thaïlande / Analysis of interactions between rubber tree (Hevea brasiliensis Mull. Arg.) and inter-crop roots in young plantations of NE Thailand

Gonkhamdee, Santimaitree 01 July 2010 (has links)
Pour d'évidentes raisons agronomiques et environnementales, être en mesure de concevoir et mettre en place des systèmes de culture dans lesquels les plantes accèdent aux ressources de manière optimale revêt une importance cruciale pour tous les intervenants impliqués dans la production agricole. Les techniques d'intensification telles que la mise en place de cultures d'inter-rang et l'agro-foresterie visent à accroître la productivité globale des terres tout en assurant la durabilité des agro-écosystèmes, via une optimisation de l'utilisation des ressources environnementales (lumière, eau et nutriments) par les plantes et une préservation des cycles géochimiques. En théorie, les moyens d'atteindre ces objectifs sont nombreux mais en pratique, les interactions souterraines sont complexes et difficiles à mesurer, de sorte que les progrès réalisés dans la conception d'agro-écosystèmes améliorés et durables demeurent modestes. Dans ce contexte, l'objectif de ce travail a été d'évaluer, au travers de mesures racinaires detaillées en rhizotron et au champ, les effets des cultures d'inter-rang sur la croissance des jeunes hévéas. La dynamique des interactions souterraines a été étudiée, tant au niveau de la racine individuelle qu'à celui du système racinaire entier, sur la base, notamment, de descriptions numériques détaillées. Une telle approche a permis de proposer, en outre, une voie novatrice pour l'analyse de la dynamique racinaire à l'echelle du systeme racinaire entier, à savoir l'analyse des trajectoires de croissance. Dans le cas de l'association maïs-hévéa, les expérimentations en rhizotron ont permis de mettre en evidence que les interactions souterraines entre ces deux plantes peuvent induire des modifications de la croissance de leurs racines, à la fois à l'échelle de la racine individuelle et à celle du système racinaire entier. Toutefois, une telle coordination des dynamiques racinaires des plantes associées n'a pas pu être confirmée dans le cas des traitements manioc-hévéa et arachide– hévéa. Les expérimentations au terrain ont fourni, de manière assez prévisible, une image complexe des interactions souterraines entre hévéa et cultures d’inter-rang. Toutefois, un premier résultat obtenu par le biais de la mise en place de 'pièges à racines' dans un traitement niébé-hévéa, a été de montrer que ces deux plantes n'avaient pas un comportement compétitif marqué l'une vis-à-vis de l'autre. Il est également apparu que les hévéas paraissent ‘investir’ dans des racines ‘coûteuses’, car de faible longueur spécifique, probablement pour assurer une certaine durabilité de ces organes, tandis que les cultures d’inter-rang favorisent l'allocation des assimilâts vers des racines de longueur spécifique élevée, de construction moins ‘coûteuses’, probablement en réponse a un impératif de croissance plus rapide (suggéré par les taux d’élongation racinaire mesurés au cours des expérimentations en rhizotron). Enfin, excepté le cas du manioc, l’introduction de cultures d’inter-rang telles que le maïs et l'arachide n'a pas eu d'impact significatif sur le développement des jeunes hévéas, comme en attestent l'évolution de leur circonférence, hauteur et développement foliaire. Ce résultat de terrain est compatible avec les résultats des expérimentations en rhizotron qui n'ont démontré aucun effet inhibiteur des cultures d’inter-rang sur le développement de la partie aérienne des hévéas. Bien que les travaux présentés dans ce rapport, ne permettent pas, à eux seuls de conclure de manière définitive sur la façon dont les espèces cultivées en association peuvent se compléter mutuellement sur le plan fonctionnel, ils apportent des éléments de réponse préliminaires à cette question complexe ainsi que des méthodes permettant de les obtenir. Au total, ce travail représente donc une contribution à la conception des agro-écosystèmes durables qui deviennent de plus en plus indispensables dans le contexte d'une demande mondiale croissante en produits alimentaires et matières premières. En outre, certains des résultats obtenus dans le cadre de cette thèse ouvrent des perspectives pour des recherches plus approfondies, avec une finalité agronomique appliquée / For obvious agronomic and environmental reasons, being able to design and implement agro-ecosystems in which crops have optimal access to resources is of pivotal importance to all stakeholders involved in agricultural production. Intensification techniques such as agro-forestry or the introduction of inter-crops aim to increase land productivity while conserving geochemical cycles, to ensure the sustainability of agro-ecosystems through an optimized use of environmental resources (light, water and nutrients). In theory, there are many ways of achieving such a goal, but in practice, below-ground interactions between plants are complex and difficult to measure, so that progress with the development of sustainable agro-ecosystems has been slow and remains modest. In this context, the objective of this work was to assess the effects of inter-crops on the growth of young rubber trees, based on a detailed analysis of below-ground interactions between the associated plants. The dynamics of below-ground interactions has been studied in rhizoboxes, at both the scale of individual roots and that of the whole root system, using detailed numerical descriptions of root architecture. Such an approach resulted in the design of an innovative method for the analysis of the entire root system dynamics, namely, the analysis of growth trajectories. In the case of the maize-rubber tree association, the experiments in rhizoboxes showed that the below-ground interactions between these two plants can induce changes in root growth, at both the individual root and the whole root system levels. However, such a coordination of rooting patterns could not be confirmed in the case of the cassava-rubber tree and groundnut-rubber tree associations. Not unexpectedly, field experiments provided a rather complex picture of the underground interactions between rubber trees and inter-crops. However, initial results obtained using 'root traps' in a cowpea-rubber tree treatment indicated that these two plants were unlikely to have a marked underground competitive behavior relative to each other. Results of field experiments also indicated that, in general, rubber trees seem to 'invest' in 'expensive roots' of low specific root length, presumably to confer some degree of durability to these organs, while inter-crops favoured the allocation of assimilates to 'cheaper' roots, i.e. roots of much higher specific length, probably in response to a 'fast growth imperative' (an hypothesis supported by the root elongation rate values measured during the rhizobox experiments). Finally, to the possible exception of cassava, inter-crops were found to have no significant impact on the development of young rubber trees, as evidenced by measured changes in tree circumference, height and leaf development. This result is consistent with results from the rhizobox experiments which also showed no inhibitory effect of inter-crops on the above-ground development of rubber trees. Although the work presented in this report does not allow, in itself, to conclude firmly on the issue of the functional complementarity between plants grown in association in inter-cropping systems, they provide preliminary answers to this complex issue together with methods to obtain such answers. Overall, this work therefore represents a contribution to the design of sustainable agro-ecosystems which are becoming increasingly needed in the context of a growing global demand for food and raw materials. In addition, some of the results generated by this work open up prospects for future research for the development of sustainable agro-ecosystems
22

Avalia??o do estresse oxidativo induzido por superf?cies de tit?nio

Queiroz, Jana Dara Freires de 29 November 2011 (has links)
Made available in DSpace on 2014-12-17T14:03:39Z (GMT). No. of bitstreams: 1 JanaDFQ_DISSERT.pdf: 1850683 bytes, checksum: e5171a51c7f0d0df9cc94a873195a0f7 (MD5) Previous issue date: 2011-11-29 / Commercially pure Titanium (cp Ti) is a material largely used in orthopedic and dental implants due to its biocompatibility properties. Changes in the surface of cp Ti can determine the functional response of the cells such as facilitating implant fixation and stabilization, and increased roughness of the surface has been shown to improve adhesion and cellular proliferation. Various surface modification methods have been developed to increase roughness, such as mechanical, chemical, electrochemical and plasma treatment. An argon plasma treatment generates a surface that has good mechanical proprieties without chemical composition modification. Besides the topography, biological responses to the implant contribute significantly to its success. Oxidative stress induced by the biomaterials is considered one of the major causes of implant failure. For this reason the oxidative potential of titanium surfaces subjected to plasma treatment was evaluated on this work. CHO-k1 cells were cultivated on smooth or roughed Ti disks, and after three days, the redox balance was investigated measuring reactive oxygen species (ROS) generation, total antioxidant capacity and biomarkers of ROS attack. The results showed cells grown on titanium surfaces are subjected to intracellular oxidative stress due to hydrogen peroxide generation. Titanium discs subjected to the plasma treatment induced less oxidative stress than the untreated ones, which resulted in improved cellular ability. Our data suggest that plasma treated titanium may be a more biocompatible biomaterial. / O Tit?nio comercialmente puro (cpTi) ? amplamente utilizado em implantes ortop?dicos e dentais gra?as ?s suas propriedades f?sico-qu?micas. Mudan?as na superf?cie do cpTi podem determinar respostas funcionais nas c?lulas influenciando a fixa??o e estabiliza??o do implante. Muitos m?todos de modifica??o na superf?cie podem ser aplicados para aumentar a rugosidade como, por exemplo, tratamentos mec?nicos, qu?micos, eletroqu?micos e a plasma. Este ?ltimo, quando realizado em atmosfera de arg?nio gera uma superf?cie rugosa com boas propriedades mec?nicas sem alterar a composi??o qu?mica do material. Superf?cies rugosas geralmente s?o mais biocompat?veis que as lisas, pois esse tipo de topografia facilita os processos de ades?o e prolifera??o celular. Al?m da topografia, as rea??es biol?gicas desencadeadas em resposta ao implante contribuem de forma significativa para o sucesso do mesmo. Dentre estas rea??es, o estresse oxidativo tem sido apontado como um dos principais respons?veis por falhas na implanta??o. Diante do exposto, o potencial oxidativo das superf?cies de tit?nio tratadas e n?o tratadas a plasma em atmosfera de arg?nio foi avaliado neste trabalho. Para tanto, c?lulas CHOk1 foram cultivadas sobre as superf?cies de tit?nio (tratadas e n?o tratadas). Ap?s tr?s dias de cultivo o potencial oxidativo foi investigado por meio da quantifica??o de esp?cies reativas, an?lise da capacidade antioxidante e an?lise de biomarcadores de dano oxidativo (lipoperoxida??o, carbonila??o prot?ica e oxida??o das bases do DNA). Os resultados obtidos indicam que ambas as superf?cies de tit?nio induzem estresse oxidativo, sendo o per?xido de hidrog?nio a principal esp?cie envolvida. O tratamento a plasma reduziu os danos oxidativos e promoveu melhora na habilidade celular em responder ao estresse oxidativo. Deste modo, a modifica??o da superf?cie de tit?nio atrav?s do tratamento a plasma pode ser uma alternativa para a obten??o de um material com melhor biocompatibilidade. / 2020-01-01
23

Creating Anomalies: A Study In Player Involvement Through Narrative In Alternate Reality Games

Grimberg, Christian January 2014 (has links)
This thesis project aims to explore the relationship between the players and the fictional worlds of alternate reality games (ARGs), concentrating on the aspects of immersion, player involvement and narrative. It investigates the connection between immersion and narrative, as well as to what extent the applying of narrative to physical environments contribute to the overall immersive experience of the players. The theoretical frame incorporates different aspects of game interaction, concerning game boundaries, game mastering and player experience, and includes an analytical presentation of a number of ARGs, challenging the traditional norms of game design. The theoretical framework is accompanied by a design process exploring game mechanics and player involvement through game testing. The assumptions drawn from the research, in combination with the outcome of the design process, suggest that because narrative utilized within ARGs is interactive it differs massively from traditional narration and the fact that it intersects the physical environment gives it properties that urges its users to dynamically collaborate to unfold its discourse.
24

Transmédia Storytelling à l’ère de la convergence : processus de réception et mythe médiatique

Pichot, Alizée 10 1900 (has links)
Le jeu en réalité alternée (ARG) Why So Serious ? créé pour la promotion du film The Dark Knight (2008) réalisé par Christopher Nolan se trouve au cœur d’une stratégie de transmédia storytelling, Ce jeu s’insère dans une ère de la convergence où les pôles de la production et de la réception sont ambigus. Les différentes pratiques des joueurs relèvent de processus de réception particuliers, qui, jumelés à l’émergence d’un récit numérique décentralisé, laissent penser que de nouveaux enjeux communicationnels et narratifs se manifestent. Ce mémoire examine les processus de réception de cet ARG basé sur l’univers fictionnel de Batman et focalisé sur le personnage du Joker, et comment ils permettent l’apparition d’un récit de nature mythologique. En articulant une netnographie effectuée sur le forum officiel du jeu, Unfiction, à une analyse sémiologique visuelle des affiches de la campagne, ainsi qu’à une analyse mythologique barthésienne du récit de cette dernière, il fut possible de schématiser le circuit communicationnel dans lequel les messages émis par les producteurs et les récepteurs se déplacèrent. On se rend compte, au vu d’une telle étude, du pouvoir des usagers actifs dans le cadre d’un phénomène transmédiatique, qui à travers la réception de cet objet fut à l’origine d’un message neuf, dont la signification se nourrit de sources multiples, liées au médium lui-même, et à l’interprétation du récit fictionnel en jeu. / The alternate reality game Why So Serious ? lies at the heart of a transmedia storytelling strategy created for the promotion of the movie The Dark Knight (2008) by Christopher Nolan. This game is deeply rooted in an era of convergence in which the distinction between production and reception of media messages is blurred. Different players’ practices illustrate specific modes of reception that, linked to the emergence of a plot with multiple threads, indicate the emergence of new communicational and narrative issues. This thesis examines those specific processes of reception and their relationship to the appearance of a mythological message in which the fictional world of Batman is recentered on the character of the Joker. Through the articulation of a netnography of the game’s official forum, Unfiction, visual semiotic analysis and Barthesian mythological analysis, it was possible to schematically build a communication circuit within which the messages produced by both the cultural industries and the game players evolve. This study contributes to and contributes to an understanding of active users’ power in this transmedia phenomenon. Furthermore, it highlights the users’ ability to generate a brand new message, thus mythological, whose significance is nourished by diverse sources, from the nature of medium itself, to the interpretation of the fictional universe within the experience itself.
25

POLIMORFISMO DO GENE TP53 EM SARCOMAS DE PARTES MOLES NO ADULTO

Almeida, Priscilla Silva Rosa de 21 July 2008 (has links)
Made available in DSpace on 2016-08-10T10:39:18Z (GMT). No. of bitstreams: 1 PRISCILLA SILVA ROSA DE ALMEIDA.pdf: 3720637 bytes, checksum: b39a9c071d90058d47a3a8c7aec2c7f3 (MD5) Previous issue date: 2008-07-21 / Soft tissue sarcomas (STS) are tumors with mesodermical origin, comprising about 1% of all adult neoplasms. Because of its effect on the p53 protein coding sequence, and its association with an increased risk for some cancer types, TP53 codon 72 polymorphism has been investigated in several studies. TP53 codon 72 codes for either Arginine (p53Arg), or Proline (p53Pro) at the p53 protein primary sequence. It was demonstrated that such amino acid change affects p53 biochemical and biological properties, and several studies have been developed in order to associate TP53 codon 72 polymorphisms as a risk, and as a prognostic factor for different cancer types. Any published study on the TP53 codon 72 polymorphism in adult soft tissue sarcomas was found in the literature. The present study aimed to investigate TP53Arg/Pro polymorphism as a potential prognostic factor in 100 adult subjects with STS. Patients were assisted at the Hospital Araújo Jorge of the Associação de Combate ao Câncer em Goiás in Goiânia, Brazil. DNA from patients was obtained from formaldehyde-fixed and paraffin-embedded tissue samples stored at the Pathology Department of the institution. Control group included 85 healthy donors randomly selected from Goiânia s population and, for this group, DNA extraction was performed from peripheral blood. Polymorphism genotyping was achieved by using polymerase chain reaction (PCR) with specific primer sets for each polymorphic variant. Statistical analysis was performed by using GenePop Ò web version 3.4 software. In this study, TP53 allelic and genotypic frequencies were investigated for subjects and controls, however, any statistical difference between the two groups was found. Our study supports the evidence that p53Arg is the most frequent allele in Latin American population, but worldwide genic and genetic frequency data are conflicting because of ethnical differences among the studied populations. According to the results, no significant association was demonstrated between TP53 codon 72 polymorphism and clinocopathological characteristics such as gender, age, tumor localization, histology, tumor size, stage, grade, node status, and distant metastasis. The five-year overall survival for the study group was 48.1%. Tumors with p53Pro/Pro genotype demonstrated a reduced survival rate (30%) when compared to p53Arg/Arg (45%), and p53Arg/Pro group (54.9%), but this association was not statistically significant (p = 0.444). In the present study, the p53Arg variant was not statistically associated with a more favorable prognosis in adult STS patients. / Os sarcomas de partes moles (SPM) são tumores de origem mesodérmica, representando cerca de 1% do total das neoplasias em adultos. O polimorfismo do códon 72 do gene TP53 é extensivamente estudado por causar impacto na seqüência codificadora do gene, além de estar associado ao maior risco para o desenvolvimento de alguns tipos de câncer. Este polimorfismo resulta na expressão de arginina (p53Arg) e/ou prolina (p53Pro) na posição 72 da proteína p53. As formas polimórficas de TP53, em relação ao polimorfismo do códon 72, apresentam propriedades bioquímicas e biológicas diferentes, e por esta razão, vários estudos foram conduzidos na tentativa de associar tais formas polimórficas como fator de risco e prognóstico para inúmeras neoplasias. Entretanto, a literatura não relata nenhum estudo que associe este polimorfismo aos sarcomas de partes moles do adulto. Neste contexto, o objetivo do presente estudo foi avaliar o polimorfismo p53Arg/Pro como potencial fator de risco e/ou prognóstico em 100 casos de SPMs em adultos atendidos no Hospital Araújo Jorge da Associação de Combate ao Câncer em Goiás. O grupo controle incluiu 85 indivíduos saudáveis selecionados aleatoriamente da população da cidade de Goiânia. As amostras dos casos constituíram de tecidos fixados em formol e incluídos em parafina e, para a extração de DNA, os tecidos foram previamente desparafinizados. A extração de DNA do grupo controle foi realizada a partir de sangue periférico. Para a genotipagem do polimorfismo, a reação em cadeia da polimerase (PCR) foi realizada utilizando conjuntos de primers específicos para cada variante polimórfica. Após a análise dos dados obtidos, verificou-se que as freqüências alélicas e genotípicas não apresentaram diferenças estatisticamente significativas entre os casos e os controles. Nosso estudo corrobora com as evidências de que o alelo p53Arg é o mais comum em populações latinoamericanas. Entretanto, os dados sobre as freqüências gênicas e genotípicas da literatura mundial são conflitantes, fato que pode ser atribuído às diferenças étnicas descritas entre as populações estudadas. Nenhuma relação estatisticamente significativa foi encontrada entre o polimorfismo do códon 72 de TP53 e as características clínico-patológicas estudadas, como sexo, idade agrupada, localização, histologia, tamanho e grau histológico tumoral, estadiamento e presença de mestástases. A sobrevida global em cinco anos para o grupo estudado foi de 48,1%. As análises de sobrevida em relação ao polimorfismo de TP53 revelaram que os pacientes cujos tumores apresentaram o genótipo p53Pro/Pro tiveram sobrevida inferior (30%), quando comparados ao grupo de pacientes com os genótipos p53Arg/Arg (45%) e p53Arg/Pro (54,9%). Entretanto, essa diferença não foi estatisticamente significativa (p = 0,444). Sabese que a isoforma p53Arg apresenta função apoptótica mais marcante. Esta característica pode conferir ao paciente um melhor prognóstico da doença. No presente trabalho, contudo, não pudemos verificar que esta variante esteve associada a um prognóstico mais favorável em pacientes adultos com SPMs.
26

Analyse des interactions entre les racines d'hévéa (Hevea brasiliensis Muel. Arg.) et de cultures intercalaires dans les jeunes plantations du Nord-Est de la Thaïlande

Gonkhamdee, Santimaitree 01 July 2010 (has links) (PDF)
Pour d'évidentes raisons agronomiques et environnementales, être en mesure de concevoir et mettre en place des systèmes de culture dans lesquels les plantes accèdent aux ressources de manière optimale revêt une importance cruciale pour tous les intervenants impliqués dans la production agricole. Les techniques d'intensification telles que la mise en place de cultures d'inter-rang et l'agro-foresterie visent à accroître la productivité globale des terres tout en assurant la durabilité des agro-écosystèmes, via une optimisation de l'utilisation des ressources environnementales (lumière, eau et nutriments) par les plantes et une préservation des cycles géochimiques. En théorie, les moyens d'atteindre ces objectifs sont nombreux mais en pratique, les interactions souterraines sont complexes et difficiles à mesurer, de sorte que les progrès réalisés dans la conception d'agro-écosystèmes améliorés et durables demeurent modestes. Dans ce contexte, l'objectif de ce travail a été d'évaluer, au travers de mesures racinaires detaillées en rhizotron et au champ, les effets des cultures d'inter-rang sur la croissance des jeunes hévéas. La dynamique des interactions souterraines a été étudiée, tant au niveau de la racine individuelle qu'à celui du système racinaire entier, sur la base, notamment, de descriptions numériques détaillées. Une telle approche a permis de proposer, en outre, une voie novatrice pour l'analyse de la dynamique racinaire à l'echelle du systeme racinaire entier, à savoir l'analyse des trajectoires de croissance. Dans le cas de l'association maïs-hévéa, les expérimentations en rhizotron ont permis de mettre en evidence que les interactions souterraines entre ces deux plantes peuvent induire des modifications de la croissance de leurs racines, à la fois à l'échelle de la racine individuelle et à celle du système racinaire entier. Toutefois, une telle coordination des dynamiques racinaires des plantes associées n'a pas pu être confirmée dans le cas des traitements manioc-hévéa et arachide- hévéa. Les expérimentations au terrain ont fourni, de manière assez prévisible, une image complexe des interactions souterraines entre hévéa et cultures d'inter-rang. Toutefois, un premier résultat obtenu par le biais de la mise en place de 'pièges à racines' dans un traitement niébé-hévéa, a été de montrer que ces deux plantes n'avaient pas un comportement compétitif marqué l'une vis-à-vis de l'autre. Il est également apparu que les hévéas paraissent 'investir' dans des racines 'coûteuses', car de faible longueur spécifique, probablement pour assurer une certaine durabilité de ces organes, tandis que les cultures d'inter-rang favorisent l'allocation des assimilâts vers des racines de longueur spécifique élevée, de construction moins 'coûteuses', probablement en réponse a un impératif de croissance plus rapide (suggéré par les taux d'élongation racinaire mesurés au cours des expérimentations en rhizotron). Enfin, excepté le cas du manioc, l'introduction de cultures d'inter-rang telles que le maïs et l'arachide n'a pas eu d'impact significatif sur le développement des jeunes hévéas, comme en attestent l'évolution de leur circonférence, hauteur et développement foliaire. Ce résultat de terrain est compatible avec les résultats des expérimentations en rhizotron qui n'ont démontré aucun effet inhibiteur des cultures d'inter-rang sur le développement de la partie aérienne des hévéas. Bien que les travaux présentés dans ce rapport, ne permettent pas, à eux seuls de conclure de manière définitive sur la façon dont les espèces cultivées en association peuvent se compléter mutuellement sur le plan fonctionnel, ils apportent des éléments de réponse préliminaires à cette question complexe ainsi que des méthodes permettant de les obtenir. Au total, ce travail représente donc une contribution à la conception des agro-écosystèmes durables qui deviennent de plus en plus indispensables dans le contexte d'une demande mondiale croissante en produits alimentaires et matières premières. En outre, certains des résultats obtenus dans le cadre de cette thèse ouvrent des perspectives pour des recherches plus approfondies, avec une finalité agronomique appliquée
27

Biophysical properties of the turnip yellow mosaic virus explored by coat protein mutagenesis

Powell, Joshua D. 05 April 2012 (has links)
Plant viruses have been instrumental in our understanding of the biophysical properties pertaining to non-enveloped icosahedral virus particles. A substantial amount of research has been performed over five decades on Turnip yellow mosaic virus (TYMV), arguably one of the most extensively studied icosahedral plant viruses and the type-member of the Tymovirus plant virus genus. Even with a substantial body of published scientific literature, little is known about the role of specific coat protein (CP) residues in TYMV assembly, disassembly and disencapsidation. We have shown through our mutagenesis studies that the N-terminal region of the CP that is involved in the formation of an annulus structure and is disordered in A-subunit pentamers is not essential in vivo, but annulus-forming residues are critical in ensuring virion stability and low accessibility after virus is purified (Chapter 2). We have shown that a range of amino acid residue types is tolerated within the CP N-terminus in vivo, although they can greatly affect the stability of virions and empty particles, most notably at low pH (Chapter 3). Unlike full-length CP, N-terminal deletion and substitution mutants fail to reassemble into particles in vitro (Chapter 2, 3) suggesting a critical determinant for the N-terminus in reassembly (discussed Chapter 7). This is the first documented in vitro reassembly reported for a member of the Tymoviridae family and should provide a framework for further studies. We have identified a new way to create empty artificial top component (ATC)-particles through treatment with EDTA (Chapter 6) and we also show that tymoviruses can be engineered with altered pH-dependent enhanced stability (Chapter 4). In collaboration with the Qian Wang laboratory from the University of South Carolina we have shown that an RGD (Arg-Gly-Asp) motif can be genetically engineered within the CP of TYMV, resulting in infectious particles with attractive stem-cell adhesion properties (Chapter 5). With focus on basic viral mechanisms, we have crystallized the TYMV virion and ATC particle at pH 7.7 and collected data to less than 5 Å resolution (Chapter 4, supplementary). These structures represent the first tymovirus-based structures solved above pH 5.5 and will provide insight into the N-terminal conformations within the TYMV particle. Finally, we have characterized an N-terminal CP cleavage seen after ATC formation (Chapter 4) suggesting an additional and yet uncharacterized feature associated with decapsidation. / Graduation date: 2012
28

Det var en gång en normal familj... : En normkritiskt komparativ studie av familjekonstellationer i bilderböcker. / Once upon a time there was a family... : A norm-ciritcal comparative study of family constellations in picture books.

Danielsson, Julia January 2018 (has links)
Detta arbetes syfte är att se vilka olika familjekonstellationer som existerar i ett urval av bilderböcker som utkommit mellan 1989 och 2015. Dessa familjekonstellationers framställning har jämförts med hjälp av ett normkritiskt perspektiv, analyserats utifrån rådande normer som gäller familj och familjeliv i samhället och den statistik som tagits fram över olika familjeformer i Sverige under början av 2000-talet. Resultatet visar att de fyra olika bilderböckernas familjer alla på något sätt går emot normen, men att den familj som stämmer bäst överens med bilden om hur kärnfamiljen ska se ut är den nyaste av de fyra utvalda bilderböckerna. / The aim of this study is to explore the different family constellations that exists in a selection of children’s picture books published between the years of 1989 and 2015. The representations of these family constellations have been compared by critically investigating norms that applies to families and they have been analyzed by these norms and the statistics that existed in society at the beginning of the 21th century. The result shows that all of the four chosen picture-books goes against the norm on some point, but that the newest of the four books is the one that most resembles the picture of a nuclear family.
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ARG-MATEE Automated Pipeline for Detection of Antimicrobial Resistance in WGS Data Collected from Pig Farms and Surrounding Communities / Tracking Antimicrobial Resistance at Pig Farms

Halstead, Holly January 2020 (has links)
As part of recognizing the interconnected nature of different sectors in relation to health, AMR (antimicrobial resistance) has emerged as an issue of high global importance. E. coli isolates were taken from pig farms in Thailand, which serves as a point of interest in the study of ARGs (antimicrobial resistance genes) in emerging economies. The fecal samples were collected from pigs, humans who came in contact with the pigs, and humans who did not have contact with pigs to be analyzed for ARGS, virulence genes, and plasmids. Data was analyzed with an automated pipeline in the form of ARG-MATEE, the Antimicrobial Resistance Gene Multi-Analysis Tool for Enteric E. coli, a tool designed in this study to be used here and in future investigations. ARG-MATEE regulates and records internal software versions in a produced report which also includes data tables for all non phylogeny results in Boyce–Codd normal form and data visualizations for plasmids, ARGs, virulence genes, and phylogeny. Through the use of ARG-MATEE, the iss virulence gene was seen to be significantly different between testing groups as it is present in only human testing groups, suggesting the loss of function of the iss gene in pigs, showing host specialization.
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A Phenomenology of Fostering Learning: Alternate Reality Games and Transmedia Storytelling

Wakefield, Jenny S. 05 1900 (has links)
This dissertation presents the essence of the experience of instructional designers and instructors who have used alternate reality games (ARGs) and transmedia storytelling (TS) for teaching and learning. The use of game-like narratives, such as ARGs and TS, is slowly increasing. However, we know little about the lived experiences of those who have implemented such transmedia experiences in formal or informal learning. The data consists of written transcripts from interviews with 11 co-researchers in the United States and Europe. Phenomenology was the guiding methodology. The study begins by reviewing storytelling and the use of games in learning, leading up to exploring the tradition of using ARGs and TS in learning contexts. The analysis was one of reduction leading to codes, summary stories, themes, and the essence of the experience. Co-researchers used many techniques to enlighten their learners including problem-solving, critical thinking, collaboration, encouragement, disruption, and connection-making. When successful, connection-making facilitates learner agency development by providing learners with the power to act by their own initiative. Action came through the communicated narratives and games that closely tied to real-world problems. In the context of these efforts, this study's co-researchers emerged as educational life-world learning-coaches, "sensei", who were each using strategies and techniques to move students toward meaningful real-world learning and the ability to make a difference in the world. The dissertation closes by exploring implications of this study for instructional designers and instructors interested in using alternate reality games and transmedia storytelling for teaching and learning purposes.

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