Les métaux rares, comme le niobium (Nb), le tantale (Ta), le tungstène (W) et l'étain (Sn), sont définis comme des «ressources stratégiques» ou des «matériaux critiques». Dans cette étude, nous prenons les gisements de Nb de Huangshan et de Ta de Songshugang dans le complexe de Lingshan, province de Jiangxi, en Chine du Sud, comme exemples. Les roches de ce gisement sont classées en deux catégories en fonction de la présence de micas riches en Nb et de la quantité de columbite-tantalites: granites à grain moyen avec des micas riches en Nb et sans columbite-tantalites, et granites à grain fin et pegmatites riches en columbite-tantalites. Ces columbite-tantalites sont riches en Nb et pauvres en Mn, les classant comme columbite. Ces columbites ont des zonations complexes liées à des processus répétitifs. Notre travail indique plutôt que la formation de tels minéraux est liée à des processus de mélanges multiples avec au moins deux types de magmas. Les granites à grain moyen dans la suite Huangshan sont différents des autres granites du complexe de Lingshan par la composition de leurs micas: Li-annite (granite MA) et "protolithionite" (granite MP). Ils sont caractérisés par des teneurs Nb élevées (moyenne de 144 ppm en MP et 158 ppm en MA) et des rapports Nb/Ta très élevés (moyenne 15,3 en MP et 31,2 en MA). Le niobium est principalement hébergé dans les micas, avec une teneur moyenne en Nb de 1347 ppm dans les Li annites, et 884 ppm dans le «protolithionite», concentrations encore jamais mesurées dans les micas d’origine magmatique. Avec un contenu estimé à ~80 kt Nb, les granites de Huangshan représentent un nouveau style potentiel de ressource de Nb. Le granite à albite de Songshugang est localisé dans l'ouest du complexe de Lingshan et est enrichi en Ta. Le granite de Songshugang n’affleure pas et est se trouve sous des couches de granites à feldspath K-topaze, de greisens et de pegmatite. Tous les granites et pegmatites sont fortement peralumineux. Les minéraux de columbite-tantalites, de zircons et de cassitérites sont constants pour chaque type de roches et présentent les mêmes textures bi-phasées. Les caractéristiques pétrographiques indiquent que le stade précoce de columbite et de zircon ont été formés dans un environnement strictement magmatique. Le stade postérieur de ces minéraux a été influencé par des circulations fluides à la transition magmatique-hydrothermale. Les micas montrent également une texture en deux étapes, avec une grande quantité de d’inclusions de columbite-tantalites. L'enrichissement en Rb dans les bordures (Znw-II) est le résultat d’un fractionnement magmatique, comme démontré par la diminution de la teneur en Nb (16,3-108 ppm comparé avec 109-313 ppm pour le coeur). Cependant, les teneurs faibles et invariables du Ta, W et Sn démontrent que le magma résiduel n'a eu aucune influence sur les processus post-magmatiques postérieurs, contrairement aux minéraux de columbite-tantalites. Enfin, les datations U-Pb in-situ sur zircons et columbite-tantalites démontrent que les granites de Huangshan et de Songshugang se sont mis en place vers 130 Ma durant l’épisode tardi-Yanshanien (Crétacé), au même moment que l’ensemble des roches magmatiques formant le complexe de Lingshan. Ce résultat indique que cette période géologique est d’intérêt pour la formation de ressources en Nb-Ta, définissant une nouvelle période géologique prospective pour ces ressources / Rare metals, including niobium (Nb), tantalum (Ta), tungsten (W) and tin (Sn), are defined as “strategic resources” or “critical materials”. For this work, we studied the Huangshan Nb deposit and Songshugang Ta deposit, in the Lingshan complex, Jiangxi Province, South China, as examples. The rocks from Huangshan granite are classified in two categories based on the occurrence of Nb-rich mica and the amount of columbite-tantalites minerals: medium-grained granites with Nb-rich mica and devoided of columbite-tantalites and fine-grained granites and pegmatites rich in columbite-tantalite minerals. Columbite-tantalite minerals are classified as columbite-(Fe), and characterized by complex zonings with various “go and back” processes, indicating that their formation is linked to multi-mixing processes of two different magma sources. The medium-grained granites in the Huangshan suite differed from the other granites of the Lingshan complex by their mica compositions: lithian annite (MA granite) and “protolithionite” (MP granite). They are characterized by elevated Nb contents (average 144 ppm in MP and 158 ppm in MA) and very high Nb/Ta ratios (average 15.3 in MP and 31.2 in MA). Niobium is mainly hosted in the micas, with an average Nb content of 1,347 ppm in the lithian annite, and 884 ppm in the “protolithionite”. Such contents are the highest ever reported in magmatic-related micas. With an estimated content of ~80 kt Nb, the Huangshan granites represent a new style of potential Nb resource. The Songshugang albite granite is found in the west of Lingshan complex and is specifically enriched in Ta. The major Songshugang albite granite is buried and covered by layers of K-feldspar granite, greisen and pegmatite. All the granites are strongly peraluminous. The compositions of columbite-tantalite minerals, the zircons and cassiterites are constant and display a similar two-stage texture. Petrographic features indicate that the early-stage columbite and zircon were formed in magmatic environment, whereas the later-stage of rare-element minerals were influenced by fluid fluxes at the magmatic-hydrothermal transitional stage. Micas also show a two-stage texture. The Rb-enrichment in the margin of the zinnwaldite is the result of magmatic fractionation, as also demonstrated by the decrease of Nb contents (16.3-108 ppm compare with core of 109-313 ppm). The invariable low contents of Ta, W and Sn demonstrate that the residual melt has no influence on later post-magmatic stages, contrary to the columbite minerals. Finally, in-situ U-Pb dating of zircon and columbite-tantalite by SIMS and LA-ICP-MS indicates that both Huangshan and Songshugang granites were emplaced at ca. 130 Ma during Later Yanshanian (or Cretaceous) and contemporary with the formation of the Lingshan complex. This result indicates that the Later Yanshanian is a prospective geological period for Nb-Ta deposits, and this result enlarges the time frame of rare-metal mineralization.

In the LCD display products source section LED light display product is OK to replace the traditional CCFL light display products, especially in the NB computer and computer monitor are almost over two to three years CCFL products will be completely out of the market. The LCD itself does not glow and need another light source to support it. Backlight module can provide light source to LCD display product. In the early the light source of backlight module is CCFL. But LED light source is going to replace CCFL from 2007. Most of all new developments in the field of the NB computer backlight module changes light source from CCFL to LED. Even the computer monitor light source is starting to use LED too. The development technologies and production quality of the LED backlight module are significant challenges in LED backlight module factory. The purpose of this study was to identify development technologies and production technologies factors of bottlenecks, and finding a solution. And can provide some help to LED backlight module industry terms. This study selects ' 8D process ' to be analysis model. And collect 5 backlight module factories development experience and production status data. Hope these data through 8D analysis process can find the major related factors of development technologies and production technologies. In-depth research, look forward to finding out the production technologies relevant factors oppression ' technical specification ' production. This study is expected to be able to find some effect LED backlight module process yield factor, then apply the stratification out product issues and process issues, this study is intended for process issue do take an in-depth look at the problem and solution, but about product issue will be' design solutions ' way to describe. I believe this research can help LED backlight module industry to reduce production cost and improve the development speed.

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Why did the people of New Brunswick fail to accept the agreement between the governments of New Brunswick and Québec to sell NB Power to Hydro-Québec? This research seeks to answer that question by examining the arguments both for and against the proposed sale of NB Power using historical institutionalism. It determines that NB Power is on two concurrent paths that are linked, yet distinct. This research then determines that the agreement to sell NB Power was a critical juncture that failed, since it was never finalized, but succeeded in creating a new momentum for change in New Brunswick.

In response to viral infection, host cells activate various antiviral defence mechanisms to inhibit virus replication. Therefore in order for a virus to replicate efficiently, it must counteract cellular antiviral defence. Promyelocytic leukemia protein (PML) is a cellular protein involved in intrinsic immunity. It inherently forms nuclear bodies (PML-NBs) that assemble at the site of viral genomes. Proteins related to epigenetic regulation are recruited to PML-NBs, and silence viral gene transcription. This study focuses on the role of two herpes simplex virus type 2 (HSV-2) proteins, ICP0 and Us3, in disrupting PML-NBs and counteracting cellular antiviral defence. En passant mutagenesis was used to create recombinant HSV-2 viruses lacking ICP0, Us3, or both ICP0 and Us3. Growth analysis of these recombinants indicates no growth defects for the ICP0Δ virus, while the Us3Δ virus grows to one log lower titres than wild type virus (WT). By contrast, the ICP0Δ virus displays a delay in PML-NB disruption, but the Us3Δ virus is as efficient as WT. However, Us3 is still important for PML-NB disruption, since the ICP0Δ/Us3Δ double mutant exhibits a greater delay than the ICP0Δ single mutant. Although PML is a mediator of the interferon (IFN) response and it was predicted that ICP0 and Us3 interfere with the IFN response through disruption of PML-NBs, my results show that only some HSV-2 Us3Δ clones are hypersensitive to the effects IFN, and others are resistant. Us3 affects more than one cellular pathway, and those cellular pathways are affected by more than one viral protein. I conclude that the activities of multiple viral proteins create a fine balance between activating cellular pathways to promote virus replication, and inhibiting cellular antiviral defence. / Thesis (Master, Microbiology & Immunology) -- Queen's University, 2014-01-23 10:55:16.715

For many years, meanings and interpretations of artefacts that are taken to represent African culture including the Ife bronzes have been predominantly produced and fixed by a team of western curatorial experts (Ciolfi, 2012). Such museum practices have prevented visitors and the people being represented by the artefact from participating in the process of interpretation and meaning-making. In the particular case of the ‘Ife bronzes’, the previous meaning and implications of the Ife ‘bronzes’ as part of ‘the cradle of the world’, according to Yoruba oral traditions, are yet to be given the amount of attention they deserve. For a long time the interpretations and meanings produced by curators were drawn from the writings and accounts of earlier western travellers, explorers and colonial officials whose culture affected how the Ife bronzes have been perceived and interpreted (Coombes, 1997: Vogel, 1999). Today despite the impact of ‘the new museology’, strong traces of such biased interpretations and meanings are still evident in the framing of the Ife bronze head, exhibited at the British Museum Sainsbury African gallery as a ‘funerary object’ in postcolonial times. Such narratives highlight ‘relations of power and not relations of meanings’ (Foucault, 1980:114). These contemporary exhibitionary frames highlight the need for interpretations and meanings that will consider how changing roles, ownership, usage, political situations and geographical location have affected and will affect the Ife bronzes. In this thesis I carry out this work, documenting the social life of the Ife bronzes from pre-colonial Ife to postcolonial digital British Museum. I argue that there is a need for a new space that will encourage rewriting, revising and representing the Ife bronzes in a more capacious way to depict their changing meaning as they journeyed through time. This theory is in line with Hall (1997) and Foucault’s (1980) theories that meanings and interpretations are not static but are affected by time and changing context. The thesis therefore explores the multifaceted political, economical and sociocultural implications of the Ife bronzes. Despite these wider implications of Ife bronzes, they are still only too often shrouded in narratives that tend to validate the supremacy, civilisation and intellectual ‘supremacy’ of the West instead of substantiating the ingenuity, civilisation and intellectual capabilities of Africa. Digitisation is critically considered as offering a potential new space for representing Ife bronzes in a new light that might allow meanings with postcolonial ideology to emerge. Focusing on different periods involving the Ife bronzes (the pre-colonial, colonial and postcolonial) the thesis explores the potentials of digital representation. The thesis concludes that digital representation but only combined with a critical contextual approach, have the potentials of initiating a more thorough decolonisation of the Ife bronzes through an inclusive participatory culture.

This thesis presents a conceptual knot, namely of how to sustain the intentionally temporary. Part of the original contribution of this thesis lies in exploring what it means for an artwork to be temporary, tracing the historical context from the twentieth century onwards, thereby establishing the category of temporary artworks, and providing thoughts on how to care for temporary artworks so that they might be known and experienced by future audiences. On the basis of this research, a practical proposal is developed for what a retrospective of temporary artworks might look like. Temporary artworks should be considered as a category unto their own because of the specific set of constraints which set them apart: they are physical works of art which exist for an intentionally limited amount of time, and are created only once. These specific constraints problematize the engagement of future audiences due to the works’ very limited and singular existence as a physical work. In order to address the issue of how to (re)visit impermanence, I develop the claim that what is passed on from a temporary artwork is contingent on the stakeholders, including the primary audience, who are posited as a group of unintentional archivists holding stock in a type of living archive. After their material unmaking, temporary artworks can be experienced through the notion that ‘the artwork is not present’, a riff on artist Marina Abramović’s retrospective work The Artist is Present (2010). A retrospective of temporary artworks would consist of memories and documents contextualizing their fragmentary nature, highlighting what Severin Fowles discusses as ‘the carnality of absence’. A clarification of what is missing assists in sustaining what I develop and describe as ‘the performance of loss’, a critical part of temporary artworks. Stewarding a temporary artwork into the future thus depends on letting the material object go, and contextualizing its presence, loss, and absence for future audiences.

L'objectif de ce travail était l'élaboration par ablation laser pulsé (PLD) et la caractérisation de couches minces d'oxydes dans le système K-Nb-O, et plus précisément d'une phase de structure bronze de tungstène quadratique (TTB) sous forme de nanorods, potentiellement intéressante dans le contexte de la recherche de nouveaux piézoélectriques sans plomb. Malgré une forte compétition de croissance entre les différentes phases, l'étude approfondie des conditions de dépôt a montré la possibilité d'obtenir les phases KNb3O8, K4Nb6O17, K6Nb10,88O30 (TTB) et KNbO3, en films minces après une phase d’optimisation essentielle. Nous avons déterminé l'influence des conditions de dépôt sur la formation et la nanostructuration de ces composés en couches minces. En particulier, il a été démontré que la température et la composition de la cible PLD avaient une forte influence sur la croissance de la phase de structure TTB. Une étude plus approfondie de ces phases a révélé que toutes avaient une morphologie spécifique liée à leur structure anisotrope, que nous avons pu contrôler par la croissance épitaxiale sur les substrats SrTiO3 orienté (100) et (110). L'existence d'une activité piézoélectrique dans des couches minces de la phase TTB, mise en évidence par PFM, lui confère un intérêt certain. Cette phase TTB a également été obtenue dans le système Na-K-Nb-O, très connu pour ses propriétés piézoélectriques et ferroélectriques, ouvrant la voie sur de nouvelles recherches. / The purpose of this work was the elaboration by pulsed laser deposition (PLD) and the characterization of thin films of oxides in the K-Nb-O system, and more precisely that of a tetragonal tungsten bronze phase (TTB) as nanorods, of potential interest as a new lead free piezoelectric. In spite of a strong growth competition between the different phases, the detailed study of the deposition conditions showed that it is possible to obtain KNb3O8, K4Nb6O17, K6Nb10,88O30 (TTB ) and KNbO3 in thin films form after an important optimization step. We have determined the influence of these deposition conditions on the formation and the nanostructuration of these compounds as thin films. In particular, it was shown that the temperature and the PLD target’s composition has a strong influence on the growth of the TTB structure. A further study of these phases revealed that all have a specific morphology related to their anisotropic structure, that we have controlled by the epitaxial growth on the (100) and (110) SrTiO3 substrates. The existence of a piezoelectric activity in the TTB thin films, evidenced by PFM, gives a great interest to this phase. This TTB phase was also obtained in the Na-K-Nb-O system, well known for its piezoelectric and ferroelectric properties, opening the way to new research.

The thesis aims to develop an understanding of the nature and evolution of brick temple architecture in the subcontinent, focusing in particular on terraced Hindu structures of the fourth to sixth centuries CE. It also seeks to advance understanding of the iconography and artistry of the terracotta relief panels that once graced the outer walls or platforms of Gupta period brick temples. To date, scholarship on Hindu temple architecture of the Gupta period has primarily focused on cave and structural stone temples, while brick temple architecture of the epoch, along with terracotta reliefs and sculptures, have largely been confined to the margins of historical studies. This approach has led to the formation of a somewhat distorted picture of the architectural landscape of the Gupta period. To address this shortcoming, all of the known terraced structures in the subcontinent have been mapped in order to establish an understanding of the development and dissemination of this mode of architecture. The architectural form and relief sculpture of the vast terraced brick Śaiva monument known as ACI or Bhimgaja, situated at the heart of the ancient fortress city of Ahichhatrā in Uttar Pradesh, forms the main case study for the thesis - with architecture being the subject of the first half of the thesis. ACI is compared with a terraced brick Vaiṣṇava structure at Pawāyā in Madhya Pradesh, formerly the Nāga centre of Padmāvatī, and with the only standing brick temple of the Gupta period, at Bhītargāon in Uttar Pradesh. Despite the scale and complexity of the former two monuments, neither has received adequate scholarship. A series of fifth- and early sixth-century CE ornamental terracotta pilaster and frieze fragments from Ahichhatrā, held in the reserve collections of the British Museum, are examined within the context of Gupta period temple architecture; the objective being to determine where each of the fragments would have been positioned on a temple. On the basis of these artefacts and related pieces from the site, it is possible to build up a picture of the type of décor that would have adorned the exterior of ACI. The many intriguing sculptures and relief fragments from Pawāyā and Ahichhatrā are the subject of the second half of the thesis. Some of the reliefs - especially those hailing from ACI - are of great importance since they represent some of the earliest visual depictions of myths contained in the Mahābhārata and other religious texts. These reliefs and sculptures are explored within the broader context of Gupta iconography, with particular attention paid to the numerous and fascinating terracotta reliefs of the era, most of which are divorced from their original settings. Moreover, based on style and scale, some of panels evidently share the same origin and these are collated here. In addition, new interpretations are proposed for several of the plaques.

Through creative practice research this thesis investigates the concept of touch and its application to museums with the process defined as ‘practice of touch’. The main practical outcome of this thesis is an interface between the museum visitor and an untouchable museum object as part of the object interpretation. The implementation of this idea is realised with the ‘Tactual Explorations’ project. The format of this project is a tactile exhibition consisting of virtual and conventional artworks combined. The subject of the study focuses on interaction between museum visitors and exhibits in order to create an accessible and tactile solution around museums’ ‘do not touch’ policy; without being limited to but being especially for blind and partially sighted visitors. The reason behind paying special attention to these members of the audience is the significance of the sense ‘touch’ in communicating with the world around them. While the main objective of this research is to gain more understanding of the concept of ‘touch’, on a deeper level it investigates whether or not a haptic interaction with untouchable visual information can be achieved with the aid of a creative interface between the museum visitor and an untouchable museum exhibit. By using this creative interface, the aim of the research extends to gaining a better understanding of touch through curating with information design and artistic methods. The purpose behind the idea is to form an inclusive museum experience free from assumptions of just one interpreter without rejecting the traditional methods of object interpretation. The practical outcome enhances dialogue with the existing information by paying special attention to tactile properties of a museum object through a set of artworks. The project is supported by other practical experiments in order to understand the value of visual/photographic information attached to an untouchable object and involve other scholars and artists in interpreting this information tactually. While accepting museums’ policy of ‘do not touch’, the praxis of this thesis is proposed as a method of interpretation that aims to bring in the ‘missing interactivity of touch’ through an engaging tactile exhibition of physical and virtual artworks made by various artists. In contrary to more common approaches of involving artists in interpreting museum objects, in this model created works are not inspired by the original, but directly based on its texture information in order to create haptic interaction, without using a direct replica or embossed copies. In other words, this interface is presented as an addition to the object’s formal interpretation, not to replace it. The research adopts creative practice research methodology in general; and realises it with a reflective and participatory approach borrowed from action research within interpretive research paradigm. The main research strategy deployed is practice-led. Rather than staying in the boundaries of qualitative research, the study takes guidance from the manifesto of performative research which is declared as an alternative to the qualitative and quantitative research methodologies, by offering creative approaches to conducting a research project.