802 resultados para REGENERATED SILK FIBROIN


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Xinjiang, once described by Owen Lattimore as the "pivot of Asia", has played a strategically important role in China's national defense and security. Historically linked on the famous Silk Road with Central Asia, Xinjiang was crucial to East-West economic and cultural exchanges. During the period of Russian/Soviet expansion into Central Asia and Sino-Soviet rivalry, China's need for Xinjiang's defense and territorial integrity became paramount, and consequently Xinjiang's economy was relegated to the periphery.^ The demise of the Soviet Union--which resulted in the independence of five Central Asian states--and China's reform suggest dramatic new possibilities for Xinjiang's regional development as well as interregional cooperation. As China has begun to shift regional emphasis to the interior, Xinjiang's economic development will be accelerated. With the growth of Sino/Xinjiang-Central Asian relations, Xinjiang's importance will not only be borne out in terms of defense and security, but more significantly in terms of trade and economics. At the century's end and the beginning of the 21st century, Xinjiang will likely move away from the periphery and play an increasingly pivotal role in the economy. ^

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Protein coding genes are comprised of protein-coding exons and non-protein-coding introns. The process of splicing involves removal of the introns and joining of the exons to form a mature messenger RNA, which subsequently undergoes translation into polypeptide. The spliceosome is a large, RNA/protein assembly of five small nuclear RNAs as well as over 300 proteins, which catalyzes intron removal and exon ligation. The selection of specific exons for inclusion in the mature messenger RNA is spatiotemporally regulated and results in production of an enormous diversity of polypeptides from a single gene locus. This phenomenon, known as alternative splicing, is regulated, in part, by protein splicing factors, which target the spliceosome to exon/intron boundaries. The first part of my dissertation (Chapters II and III) focuses on the discovery and characterization of the 45 kilodalton FK506 binding protein (FKBP45), which I discovered in the silk moth, Bombyx mori, as a U1 small nuclear RNA binding protein. This protein family binds the immunosuppressants FK506 and rapamycin and contains peptidyl-prolyl cis-trans isomerase activity, which converts polypeptides from cis to trans about a proline residue. This is the first time that an FKBP has been identified in the spliceosome. The second section of my dissertation (Chapters IV, V, VI and VII) is an investigation of the potential role of small nuclear RNA sequence variants in the control of splicing. I identified 46 copies of small nuclear RNAs in the 6X whole genome shotgun of the Bombyx mori p50T strain. These variants may play a role in differential binding of specific proteins that mediate alternative splicing. Along these lines, further investigation of U2 snRNA sequence variants in Bombyx mori demonstrated that some U2 snRNAs preferentially assemble into high molecular weight spliceosomal complexes over others. Expression of snRNA variants may represent another mechanism by which the cell is able to fine tune the splicing process.

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Fossil fuels constitute a significant fraction of the world's energy demand. The burning of fossil fuels emits huge amounts of carbon dioxide into the atmosphere. Therefore, the limited availability of fossil fuel resources and the environmental impact of their use require a change to alternative energy sources or carriers (such as hydrogen) in the foreseeable future. The development of methods to mitigate carbon dioxide emission into the atmosphere is equally important. Hence, extensive research has been carried out on the development of cost-effective technologies for carbon dioxide capture and techniques to establish hydrogen economy. Hydrogen is a clean energy fuel with a very high specific energy content of about 120MJ/kg and an energy density of 10Wh/kg. However, its potential is limited by the lack of environment-friendly production methods and a suitable storage medium. Conventional hydrogen production methods such as Steam-methane-reformation and Coal-gasification were modified by the inclusion of NaOH. The modified methods are thermodynamically more favorable and can be regarded as near-zero emission production routes. Further, suitable catalysts were employed to accelerate the proposed NaOH-assisted reactions and a relation between reaction yield and catalyst size has been established. A 1:1:1 molar mixture of LiAlH 4, NaNH2 and MgH2 were investigated as a potential hydrogen storage medium. The hydrogen desorption mechanism was explored using in-situ XRD and Raman Spectroscopy. Mesoporous metal oxides were assessed for CO2 capture at both power and non-power sectors. A 96.96% of mesoporous MgO (325 mesh size, surface area = 95.08 ± 1.5 m2/g) was converted to MgCO 3 at 350°C and 10 bars CO2. But the absorption capacity of 1h ball milled zinc oxide was low, 0.198 gCO2 /gZnO at 75°C and 10 bars CO2. Interestingly, 57% mass conversion of Fe and Fe 3O4 mixture to FeCO3 was observed at 200°C and 10 bars CO2. MgO, ZnO and Fe3O4 could be completely regenerated at 550°C, 250°C and 350°C respectively. Furthermore, the possible retrofit of MgO and a mixture of Fe and Fe3O 4 to a 300 MWe coal-fired power plant and iron making industry were also evaluated.

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Protein coding genes are comprised of protein-coding exons and non-protein-coding introns. The process of splicing involves removal of the introns and joining of the exons to form a mature messenger RNA, which subsequently undergoes translation into polypeptide. The spliceosome is a large, RNA/protein assembly of five small nuclear RNAs as well as over 300 proteins, which catalyzes intron removal and exon ligation. The selection of specific exons for inclusion in the mature messenger RNA is spatio-temporally regulated and results in production of an enormous diversity of polypeptides from a single gene locus. This phenomenon, known as alternative splicing, is regulated, in part, by protein splicing factors, which target the spliceosome to exon/intron boundaries. The first part of my dissertation (Chapters II and III) focuses on the discovery and characterization of the 45 kilodalton FK506 binding protein (FKBP45), which I discovered in the silk moth, Bombyx mori, as a U1 small nuclear RNA binding protein. This protein family binds the immunosuppressants FK506 and rapamycin and contains peptidyl-prolyl cis-trans isomerase activity, which converts polypeptides from cis to trans about a proline residue. This is the first time that an FKBP has been identified in the spliceosome. The second section of my dissertation (Chapters IV, V, VI and VII) is an investigation of the potential role of small nuclear RNA sequence variants in the control of splicing. I identified 46 copies of small nuclear RNAs in the 6X whole genome shotgun of the Bombyx mori p50T strain. These variants may play a role in differential binding of specific proteins that mediate alternative splicing. Along these lines, further investigation of U2 snRNA sequence variants in Bombyx mori demonstrated that some U2 snRNAs preferentially assemble into high molecular weight spliceosomal complexes over others. Expression of snRNA variants may represent another mechanism by which the cell is able to fine tune the splicing process.

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This work is an investigation into collimator designs for a deuterium-deuterium (DD) neutron generator for an inexpensive and compact neutron imaging system that can be implemented in a hospital. The envisioned application is for a spectroscopic imaging technique called neutron stimulated emission computed tomography (NSECT).

Previous NSECT studies have been performed using a Van-de-Graaff accelerator at the Triangle Universities Nuclear Laboratory (TUNL) in Duke University. This facility has provided invaluable research into the development of NSECT. To transition the current imaging method into a clinically feasible system, there is a need for a high-intensity fast neutron source that can produce collimated beams. The DD neutron generator from Adelphi Technologies Inc. is being explored as a possible candidate to provide the uncollimated neutrons. This DD generator is a compact source that produces 2.5 MeV fast neutrons with intensities of 1012 n/s (4π). The neutron energy is sufficient to excite most isotopes of interest in the body with the exception of carbon and oxygen. However, a special collimator is needed to collimate the 4π neutron emission into a narrow beam. This work describes the development and evaluation of a series of collimator designs to collimate the DD generator for narrow beams suitable for NSECT imaging.

A neutron collimator made of high-density polyethylene (HDPE) and lead was modeled and simulated using the GEANT4 toolkit. The collimator was designed as a 52 x 52 x 52 cm3 HDPE block coupled with 1 cm lead shielding. Non-tapering (cylindrical) and tapering (conical) opening designs were modeled into the collimator to permit passage of neutrons. The shape, size, and geometry of the aperture were varied to assess the effects on the collimated neutron beam. Parameters varied were: inlet diameter (1-5 cm), outlet diameter (1-5 cm), aperture diameter (0.5-1.5 cm), and aperture placement (13-39 cm). For each combination of collimator parameters, the spatial and energy distributions of neutrons and gammas were tracked and analyzed to determine three performance parameters: neutron beam-width, primary neutron flux, and the output quality. To evaluate these parameters, the simulated neutron beams are then regenerated for a NSECT breast scan. Scan involved a realistic breast lesion implanted into an anthropomorphic female phantom.

This work indicates potential for collimating and shielding a DD neutron generator for use in a clinical NSECT system. The proposed collimator designs produced a well-collimated neutron beam that can be used for NSECT breast imaging. The aperture diameter showed a strong correlation to the beam-width, where the collimated neutron beam-width was about 10% larger than the physical aperture diameter. In addition, a collimator opening consisting of a tapering inlet and cylindrical outlet allowed greater neutron throughput when compared to a simple cylindrical opening. The tapering inlet design can allow additional neutron throughput when the neck is placed farther from the source. On the other hand, the tapering designs also decrease output quality (i.e. increase in stray neutrons outside the primary collimated beam). All collimators are cataloged in measures of beam-width, neutron flux, and output quality. For a particular NSECT application, an optimal choice should be based on the collimator specifications listed in this work.

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For the SNO+ neutrinoless double beta decay search, various backgrounds, ranging from impurities present naturally to those produced cosmogenically, must be understood and reduced. Cosmogenic backgrounds are particularly difficult to reduce as they are continually regenerated while exposed to high energy cosmic rays. To reduce these cosmogenics as much as possible the tellurium used for the neutrinoless double beta decay search will be purified underground. An analysis of the purification factors achievable for insoluble cosmogenic impurities found a reduction factor of $>$20.4 at 50\% C.L.. During the purification process the tellurium will come into contact with ultra pure water and nitric acid. These liquids both carry some cosmogenic impurities with them that could be potentially transferred to the tellurium. A conservative limit is set at $<$18 events in the SNO+ region of interest (ROI) per year as a result of contaminants from these liquids. In addition to cosmogenics brought underground, muons can produce radioactive isotopes while the tellurium is stored underground. A study on the rate at which muons produce these backgrounds finds an additional 1 event per year. In order to load the tellurium into the detector, it will be combined with 1,2-butanediol to form an organometallic complex. The complex was found to have minimal effect on the SNO+ acrylic vessel for 154 years.

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This project is about Fast and Female, a community-based girls’ sport organization, that focuses on empowering girls through sport. In this thesis I produce a discourse analysis from interviews with six expert sportswomen and a textual analysis of the organization’s online content – including its social media pages. I ground my analysis in poststructural theory as explained by Chris Weedon (1997) and in literature that helps contextualize and better define empowerment (Collins, 2000; Cruikshank, 1999; Hains, 2012; Sharma, 2008; Simon, 1994) and neoliberalism (Silk & Andrews, 2012). My analysis in this project suggests that Fast and Female develops a community through online and in-person interaction. This community is focused on girls’ sport and empowerment, but, as the organization is situated in a neoliberal context, organizers must take extra consideration in order for the organization to develop a girls’ sport culture that is truly representative of the desires and needs of the participants rather than implicit neoliberal values. It is important to note that Fast and Female does not identify as a feminist organization. Through this thesis I argue that Fast and Female teaches girls that sport is empowering – but, while the organization draws on “empowerment,” a term often used by feminists, it promotes a notion of empowerment that teaches female athletes how to exist within current mainstream and sporting cultures, rather than encouraging them to be empowered female citizens who learn to question and challenge social inequity. I conclude my thesis with suggestions for Fast and Female to encourage empowerment in spite of the current neoliberal situation. I also offer a goal-setting workbook that I developed to encourage girls to set goals while thinking about their communities rather than just themselves.

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In June 2015, legal frameworks of the Asian Infrastructural Investment Bank were signed by its 57 founding members. Proposed and initiated by China, this multilateral development bank is considered to be an Asian counterpart to break the monopoly of the World Bank and the International Monetary Fund. In October 2015, China’s Central Bank announced a benchmark interest rate cut to combat the economic slowdown. The easing policy coincides with the European Central Bank’s announcement of doubts over US Fed’s commitment to raise interest rates. Global stock markets responded positively to China’s move, with the exception of the indexes from Wall Street (Bland, 2015; Elliott, 2015). In the meantime, China’s ‘One Belt, One Road’ (or New Silk Road Economic Belt) became atopic of discourse in relation to its growing global economy, as China pledged $40 billion to trade and infrastructure projects (Bermingham, 2015). The foreign policy aims to reinforce the economic belt from western China through Central Asia towards Europe, as well as to construct maritime trading routes from coastal China through the South China Sea (Summers, 2015). In 2012, The Economist launched a new China section, to reveal the complexity of the‘meteoric rise’ of China. John Micklethwait, who was then the chief editor of the magazine, said that China’s emergence as a global power justified giving it a section of its own(Roush, 2012). In July 2015, Hu Shuli, the former chief editor of Caijing, announced the launch of a think tank and financial data service division called Caixin Insight Group, which encompasses the new Caixin China Purchasing Managers Index (PMI). Incooperation with with Markit Group, a principal global provider of PMI, the index soon became a widely cited economic indicator. One anecdote from November’s Caixin shows how much has changed: in a high-profile dialogue between Hu Shuli and Kevin Rudd, Hu insisted on asking questions in English; interestingly, the former Prime Minister of Australia insisted on replying in Chinese. These recent developments point to one thing: the economic ascent of China and its increasing influence on the power play between economics and politics in world markets. China has begun to take a more active role in rule making and enforcement under neoliberal frameworks. However, due to the country’s size and the scale of its economy in comparison to other countries, China’s version of globalisation has unique characteristics. The ‘Capitalist-socialist’ paradox is vital to China’s market-oriented transformation. In order to comprehend how such unique features are articulated and understood, there are several questions worth investigating in the realms of media and communication studies,such as how China’s neoliberal restructuring is portrayed and perceived by different types of interested parties, and how these portrayals are de-contextualised and re-contextualised in global or Anglo-American narratives. Therefore, based on a combination of the themes of globalisation, financial media and China’s economic integration, this thesis attempts to explore how financial media construct the narratives of China’s economic globalisation through the deployment of comparative and multi-disciplinary approaches. Two outstanding elite financial magazines, Britain’s The Economist, which has a global readership and influence, and Caijing, China’s leading financial magazine, are chosen as case studies to exemplify differing media discourses, representing, respectively, Anglo-American and Chinese socio-economic and political backgrounds, as well as their own journalistic cultures. This thesis tries to answer the questions of how and why China’s neoliberal restructuring is constructed from a globally-oriented perspective. The construction primarily involves people who are influential in business and policymaking. Hence, the analysis falls into the paradigm of elite-elite communication, which is an important but relatively less developed perspective in studying China and its globalisation. The comparing of characteristics of narrative construction are the result of the textual analysis of articles published over a ten-year period (mid-1998 to mid-2008). The corpus of samples come from the two media outlets’ coverage of three selected events:China becoming a member of the World Trade Organization, its outward direct investment, and the listing of stocks of Chinese companies in overseas exchanges, which are mutually exclusive in sample collection and collectively exhaustive in the inclusion of articles regarding China’s economic globalisation. The findings help to understand that, despite language, socio-economic and political differences, elite financial media with globally-oriented readerships share similar methods of and approaches to agenda setting, the evaluation of news prominence, the selection of frame, and the advocacy of deeply rooted neoliberal ideas. The comparison of their distinctive features reflects the different phases of building up the sense of identity in their readers as global elites, as well as the different economic interests that are aligned with the corresponding readerships. However, textual analysis is only relevant in terms of exploring how the narratives are constructed and the elements they include; textual analysis alone prevents us from seeing the obstacles and the constrains of the journalistic practices of construction. Therefore, this thesis provides a brief discussion of interviews with practitioners from the two media, in order to understand how similar or different narratives are manifested and perceived, how the concept of neoliberalism deviates from and is justified in the Chinese context, and how and for what purpose deviations arise from Western to Chinese contexts. The thesis also contributes to defining financial media in the domain of elite communication. The relevant and closely interlocking concepts of globalisation, elitism and neoliberalism are discussed, and are used as a theoretical bedrock in the analysis of texts and contexts. It is important to address the agenda-setting and ideological role of elite financial media, because of its narrative formula of infusing business facts with opinions,which is important in constructing the global elite identity as well as influencing neoliberal policy-making. On the other hand, ‘journalistic professionalism’ has been redefined, in that the elite identity is shared by the content producer, reader and the actors in the news stories emerging from the much-compressed news cycle. The professionalism of elite financial media requires a dual definition, that of being professional in the understanding of business facts and statistics, and that of being professional in the making sense of stories by deploying economic logic.

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This article intends to study the evolution of the European Union foreign policy in the Southern Caucasus and Central Area throughout the Post-Cold War era. The aim is to analyze Brussels’ fundamental interests and limitations in the area, the strategies it has implemented in the last few years, and the extent to which the EU has been able to undermine the regional hegemons’ traditional supremacy. As will be highlighted, the Community’s chronic weaknesses, the local determination to preserve sovereignty and an increasing international geopolitical competition undermine any European aspiration to become a pre-eminent actor at the heart of the Eurasian continent in the near future.

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The Lagrangian progression of a biological community was followed in a filament of the Mauritanian upwelling system, north-west Africa, during offshore advection. The inert dual tracers sulfur hexafluoride and helium-3 labelled a freshly upwelled patch of water that was mapped for 8 days. Changes in biological, physical, and chemical characteristics were measured, including phytoplankton productivity, nitrogen assimilation, and regeneration. Freshly upwelled water contained high nutrient concentrations but was depleted in N compared to Redfield stoichiometry. The highest rate of primary productivity was measured on the continental shelf, associated with high rates of nitrogen assimilation and a phytoplankton community dominated by diatoms and flagellates. Indicators of phytoplankton abundance and activity decreased as the labelled water mass transited the continental shelf slope into deeper water, possibly linked to the mixed layer depth exceeding the light penetration depth. By the end of the study, the primary productivity rate decreased and was associated with lower rates of nitrogen assimilation and lower nutrient concentrations. Nitrogen regeneration and assimilation took place simultaneously. Results highlighted the importance of regenerated NHC 4 in sustaining phytoplankton productivity and indicate that the upwelled NO3 pool contained an increasing fraction of regenerated NO3 as it advected offshore. By calculating this fraction and incorporating it into an f ratio formulation, we estimated that of the 12:38Tg C of annual regional production, 4:73Tg C was exportable.

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The Lagrangian progression of a biological community was followed in a filament of the Mauritanian upwelling system, north-west Africa, during offshore advection. The inert dual tracers sulfur hexafluoride and helium-3 labelled a freshly upwelled patch of water that was mapped for 8 days. Changes in biological, physical, and chemical characteristics were measured, including phytoplankton productivity, nitrogen assimilation, and regeneration. Freshly upwelled water contained high nutrient concentrations but was depleted in N compared to Redfield stoichiometry. The highest rate of primary productivity was measured on the continental shelf, associated with high rates of nitrogen assimilation and a phytoplankton community dominated by diatoms and flagellates. Indicators of phytoplankton abundance and activity decreased as the labelled water mass transited the continental shelf slope into deeper water, possibly linked to the mixed layer depth exceeding the light penetration depth. By the end of the study, the primary productivity rate decreased and was associated with lower rates of nitrogen assimilation and lower nutrient concentrations. Nitrogen regeneration and assimilation took place simultaneously. Results highlighted the importance of regenerated NHC 4 in sustaining phytoplankton productivity and indicate that the upwelled NO3 pool contained an increasing fraction of regenerated NO3 as it advected offshore. By calculating this fraction and incorporating it into an f ratio formulation, we estimated that of the 12:38Tg C of annual regional production, 4:73Tg C was exportable.

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Gas phase photoreforming of methanol using a Pt/TiO2 photocatalyst has been performed under flow conditions at elevated temperatures. Comparing the activity of the reforming process as a function of temperature under dark and irradiated conditions shows a significant enhancement in the rate of H2 production using the photo-assisted conditions at temperatures between 100-140 °C. At higher temperatures, the effect of irradiation is small with the process dominated by the thermal process. Deactivation of the catalyst was observed under irradiation but the catalyst was easily regenerated using an oxygen treatment at 120 °C. Diffuse Reflectance Infra-red Fourier Transform Spectroscopy (DRIFTS) showed that the activity of the catalyst could be correlated with the presence of the photogenerated trapped electrons. In addition, lower amounts of CO adsorbed on Pt, compared to those observed in the dark reaction, were found for the UV-irradiated systems. It is proposed that CO and adsorbed intermediates, such as formate, can act as inhibitors in the photoreforming process and this is further supported by the observation that, before and after the regeneration process in O2, the CO and surface adsorbed organic intermediate products are removed and the activity is recovered.

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À la fin du 19e siècle, Dr. Ramón y Cajal, un pionnier scientifique, a découvert les éléments cellulaires individuels, appelés neurones, composant le système nerveux. Il a également remarqué la complexité de ce système et a mentionné l’impossibilité de ces nouveaux neurones à être intégrés dans le système nerveux adulte. Une de ses citations reconnues : “Dans les centres adultes, les chemins nerveux sont fixes, terminés, immuables. Tout doit mourir, rien ne peut être régénérer” est représentative du dogme de l’époque (Ramón y Cajal 1928). D’importantes études effectuées dans les années 1960-1970 suggèrent un point de vue différent. Il a été démontré que les nouveaux neurones peuvent être générés à l’âge adulte, mais cette découverte a créé un scepticisme omniprésent au sein de la communauté scientifique. Il a fallu 30 ans pour que le concept de neurogenèse adulte soit largement accepté. Cette découverte, en plus de nombreuses avancées techniques, a ouvert la porte à de nouvelles cibles thérapeutiques potentielles pour les maladies neurodégénératives. Les cellules souches neurales (CSNs) adultes résident principalement dans deux niches du cerveau : la zone sous-ventriculaire des ventricules latéraux et le gyrus dentelé de l’hippocampe. En condition physiologique, le niveau de neurogenèse est relativement élevé dans la zone sous-ventriculaire contrairement à l’hippocampe où certaines étapes sont limitantes. En revanche, la moelle épinière est plutôt définie comme un environnement en quiescence. Une des principales questions qui a été soulevée suite à ces découvertes est : comment peut-on activer les CSNs adultes afin d’augmenter les niveaux de neurogenèse ? Dans l’hippocampe, la capacité de l’environnement enrichi (incluant la stimulation cognitive, l’exercice et les interactions sociales) à promouvoir la neurogenèse hippocampale a déjà été démontrée. La plasticité de cette région est importante, car elle peut jouer un rôle clé dans la récupération de déficits au niveau de la mémoire et l’apprentissage. Dans la moelle épinière, des études effectuées in vitro ont démontré que les cellules épendymaires situées autour du canal central ont des capacités d’auto-renouvellement et de multipotence (neurones, astrocytes, oligodendrocytes). Il est intéressant de noter qu’in vivo, suite à une lésion de la moelle épinière, les cellules épendymaires sont activées, peuvent s’auto-renouveller, mais peuvent seulement ii donner naissance à des cellules de type gliale (astrocytes et oligodendrocytes). Cette nouvelle fonction post-lésion démontre que la plasticité est encore possible dans un environnement en quiescence et peut être exploité afin de développer des stratégies de réparation endogènes dans la moelle épinière. Les CSNs adultes jouent un rôle important dans le maintien des fonctions physiologiques du cerveau sain et dans la réparation neuronale suite à une lésion. Cependant, il y a peu de données sur les mécanismes qui permettent l'activation des CSNs en quiescence permettant de maintenir ces fonctions. L'objectif général est d'élucider les mécanismes sous-jacents à l'activation des CSNs dans le système nerveux central adulte. Pour répondre à cet objectif, nous avons mis en place deux approches complémentaires chez les souris adultes : 1) L'activation des CSNs hippocampales par l'environnement enrichi (EE) et 2) l'activation des CSNs de la moelle épinière par la neuroinflammation suite à une lésion. De plus, 3) afin d’obtenir plus d’information sur les mécanismes moléculaires de ces modèles, nous utiliserons des approches transcriptomiques afin d’ouvrir de nouvelles perspectives. Le premier projet consiste à établir de nouveaux mécanismes cellulaires et moléculaires à travers lesquels l’environnement enrichi module la plasticité du cerveau adulte. Nous avons tout d’abord évalué la contribution de chacune des composantes de l’environnement enrichi à la neurogenèse hippocampale (Chapitre II). L’exercice volontaire promeut la neurogenèse, tandis que le contexte social augmente l’activation neuronale. Par la suite, nous avons déterminé l’effet de ces composantes sur les performances comportementales et sur le transcriptome à l’aide d’un labyrinthe radial à huit bras afin d’évaluer la mémoire spatiale et un test de reconnaissante d’objets nouveaux ainsi qu’un RNA-Seq, respectivement (Chapitre III). Les coureurs ont démontré une mémoire spatiale de rappel à court-terme plus forte, tandis que les souris exposées aux interactions sociales ont eu une plus grande flexibilité cognitive à abandonner leurs anciens souvenirs. Étonnamment, l’analyse du RNA-Seq a permis d’identifier des différences claires dans l’expression des transcripts entre les coureurs de courte et longue distance, en plus des souris sociales (dans l’environnement complexe). iii Le second projet consiste à découvrir comment les cellules épendymaires acquièrent les propriétés des CSNs in vitro ou la multipotence suite aux lésions in vivo (Chapitre IV). Une analyse du RNA-Seq a révélé que le transforming growth factor-β1 (TGF-β1) agit comme un régulateur, en amont des changements significatifs suite à une lésion de la moelle épinière. Nous avons alors confirmé la présence de cette cytokine suite à la lésion et caractérisé son rôle sur la prolifération, différentiation, et survie des cellules initiatrices de neurosphères de la moelle épinière. Nos résultats suggèrent que TGF-β1 régule l’acquisition et l’expression des propriétés de cellules souches sur les cellules épendymaires provenant de la moelle épinière.

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In 2009 Avella created a series of innovative fabrics for the Yves St Laurent (YSL) collection, deploying techniques from vehicle engineering to generate new materials for a range of garments. Studying the bonding of layers of material in ceramic plate thermobonding technology, Avella conducted a series of experiments with textiles such as flannel, silk and synthetics, and material such as leather, layered with polyamide foam and textile substrate to create new, textured and insulating fabrics with beautiful surfaces and interesting forms. The lightweight properties of the foam enabled the maximum insulation/weight ratio, and the panel moulding technology brought new forms of draping prêt-a-porter fashion design. Exclusive to YSL, this technique was patented and then shown at the Premiere Vision textiles trade fair in 2010. Much documented in specialist journals this innovation also breached the trade-culture barrier and was reported and documented in mainstream newspapers (New York Herald Tribune). Avella’s background in textile workshop studio experimentation at the RCA brought to YSL textiles research for manufacture, the innovative collaboration between fashion couture and engineering laboratory experiments from vehicle design.

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Thesis (Ph.D.)--University of Washington, 2016-08