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1

Wade, A. A. "Optimising BFWA networks." Thesis, Cardiff University, 2005. http://orca.cf.ac.uk/55997/.

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2

Molony, Mary Carolyn. "Confessions: A BFA Exhibition." Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/honors/154.

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The artist discusses her Bachelor of Fine Arts Exhibition, Confessions, held at the Tipton Gallery, from November 14th to November 25th. The exhibit portrays how the artist responds to issues such as organized religion, war, and politics. Being drawn to art from the Renaissance to Baroque era, the work encorporates an "old world" aesthetic, also with an emphasis on Gothic architecture.
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3

Frazier, Jane. "Exploring the BA and BFA Curriculum." VCU Scholars Compass, 2008. http://scholarscompass.vcu.edu/etd/1554.

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This thesis is a picture of my journey as an educator. I taught at the University level from Fall 2001 – Summer 2006 before I became a graduate student at Virginia Commonwealth University in Theatre Pedagogy where I continued to teach until 2008. My education and real life experiences over the last seven plus years have contributed to my teaching methodology which is ever evolving. There were several trials and tribulations as I progressed as an educator and this is an exploration of my experience teaching in the BA and BFA curriculums.
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4

Mourão, Daniela Bastos. "Perfil de citocinas produzidas por macrófagos na presença de intimina e bundlina (BfpA) de Escherichia coli enteropatogênica." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/9/9136/tde-23082013-103356/.

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Escherichia coli enteropatogênica (EPEC) é um dos principais agentes etiológicos da diarreia infantil tanto em países desenvolvidos como em países em desenvolvimento. Esta bactéria possui dois fatores de virulência comprovadamente envolvidos na patogênese, intimina e bundle-forming pilus (BFP). Este patotipo está dividido em EPEC típica e EPEC atípica, ambos apresentam uma ilha de patogenicidade cromossomal denominada locus of enterocyte effacement (região LEE) onde está localizado o gene eae (E. coli attachment effacement), que codifica a intimina, uma proteína de membrana externa que medeia a adesão íntima da bactéria ao enterócito. Diferente da EPEC típica, as cepas de EPEC atípica não possuem o plasmídeo EAF (EPEC adherence factor) no qual encontra-se o operon bfp (bundle forming pilus) constituído por 14 genes incluindo bfpA o qual codifica a bundlina (BfpA), principal subunidade da fímbria Bfp, que possibilita a agregação bacteriana. Na infecção por EPEC ocorre grave disfunção da barreira epitelial, e uma das conseqüências é a inflamação. Na literatura, é bem descrito a interação entre as proteínas efetoras de EPEC com as células epiteliais e os processos iniciais da interação bactéria à célula hospedeira. Entretanto, poucos são os estudos que analisam a produção de citocinas em infecções por EPEC ou suas moléculas efetoras com relação a ativação de macrófagos, fundamentais para o controle do processo inflamatório e geração da resposta imune durante esta infecção. A análise das citocinas produzidas constitui uma parte importante da resposta imune e representa a tentativa do hospedeiro em lidar com um determinado microrganismo. Em função disto analisou-se o papel da intimina e do BfpA na capacidade de ativar a resposta inata mediada por macrófagos in vitro, onde avaliou-se a produção de citocinas pró-inflamatórias (TNF-α, IL-1, IL-6 e IL-12), citocina antiinflamatória (IL-10) e quimiocina (MCP-1). Os resultados demonstraram que as proteínas recombinantes intimina e BfpA são potentes ativadores de macrófagos, de forma dose dependente, produzindo TNF-α, IL-12 e IL-6, IL-10 e MCP-1, mas não IL-1β. Neste estudo não foi observado efeito sinérgico na produção de citocinas pró-inflamatórias ao associar intimina e BfpA, entretanto em dose mais elevada potenciou a produção de IL-10, um mediador antiinflamatório. O efeito imune obtido foi atribuído majoritariamente a estas proteínas uma vez que o tratamento destas com polimixina B não alterou a produção de TNF-α. Conclui-se que intimina e BfpA são potentes ativadores de macrófagos durante a resposta inata podendo colaborar para o controle do processo inflamatório durante a infecção por EPEC.
Enteropathogenic Escherichia coli (EPEC) is a common cause of childhood diarrhea in developed countries as well as developing countries. This bacterium has two proven virulence factors involved in pathogenesis, intimin and bundle-forming pilus (BFP). This pathotype EPEC is divided into typical and atypical EPEC, both having a chromosomal pathogenicity island called locus of enterocyte effacernent (LEE region) which contains the gene eae (E. coli attachment effacement). eae encodes intimin, an outer membrane protein that mediates the intimate adherence of bacteria to the enterocyte. Unlike typical EPEC, atypical EPEC strains do not possess the plasmid EAF (EPEC adherence factor) which is in the operon bfp (bundle forming pilus) consisting of 14 genes including bfpA, which encodes bundlin (BfpA), the main subunit of BFP allowing bacterial aggregation. EPEC infection occurs in severe dysfunction of the epithelial barrier, and one consequence is inflammation. In the literature, the interaction between effector proteins of EPEC and epithelial cells and the initial processes of bacterial interaction with the host cell are well described. However, there are few studies that have examined cytokine production in EPEC infections or their effector molecules with respect to macrophage activation, essential for controlling inflammation and immune response during this infection. The production of cytokines is an important part of the immune response and represents the host\'s attempt to deal with a particular microorganism. Therefore, we examined in vitro the role of intimin and BfpA in the ability to activate the innate response mediated by macrophages, where we analyzed the production of the proinflammatory cytokines TNF-α, IL-1, IL-6 and IL-12, and the antiinflammatory cytokine IL-10 and chemokine MCP-1. The results show that recombinant intimin and BfpA are potent activators of macrophages in a dose-dependent manner, where the stimulated cells produce TNF-α, IL-12 and IL-6, IL-10 and MCP-1, but not IL-1β. In this study, no synergistic effect was observed in the production of proinflammatory cytokines by combining BfpA and intimin, although production of IL-10, an antiinflammatory mediator, was potentiated at a higher dose. The effect obtained was largely attributed to these proteins, as the treatment of proteins with polymyxin B did not alter the production of TNF-α. We conclude that intimin and BfpA are potent activators of macrophages during the innate response and may contribute to the control of inflammation during infection with EPEC.
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5

von, Walden Karl-Fredrik. "BFA Essay : The human and the machine." Thesis, Konstfack, Institutionen för Konst (K), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:konstfack:diva-6073.

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6

Ingram, Jacob. "No Place Like It - A BFA Exhibition." Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/honors/42.

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Bachelor of Fine Arts Exhibition, No Place Like It, held at Tipton Street Gallery, 126 Spring Street, Downtown Johnson City, TN, from April 2nd to April 6th. The show exhibit consists largely of drawings mostly done in graphite or charcoal, an installation piece, a quilt and found objects completed between the summer of 2010 and spring of 2012. The work uses family photos and Jackalopes to show the relationship to the artist as well as ideas about family, isolation, and identity.
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7

Legrand, Frédéric. "Synthèses totales de deux analogues de la Bréfeldine A : la 15-nor-Me-BFA et la 4-epi-15-nor-Me-BFA." Nantes, 2008. http://www.theses.fr/2008NANT2041.

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La bréfeldine A (BFA) est une lactone macrocyclique isolée en 1958 d’un champignon phytopathogène Penicillium decumbens . Elle possède de nombreuses propriétés biologiques. Elle inhibe en particulier le transport des protéines du réticulum endoplasmique vers l’appareil de Golgi selon un mécanisme d’action original (inhibition interfaciale par reconnaissance d’une protéine G et de son effecteur) qui pourrait ouvrir une nouvelle voie de recherche pour la conception de médicaments. La synthèse de nouveaux analogues structuraux de la BFA qui conserveraient la même activité que la molécule naturelle, en étant moins toxiques, a dès lors été envisagée. Ce mémoire décrit les synthèses totales de la 15-nor-Me-BFA et de son épimère en C4, la 4-épi-15-nor-Me-BFA, selon une stratégie développée précédemment au laboratoire pour la synthèse de la BFC (bioprécurseur de la BFA). Ces deux analogues ont été préparés chacun en 24 étapes avec un rendement global de 2,9 %. Les résultats des tests biochimiques réalisés sur la BFA et les deux analogues nous ont permis de mieux comprendre le mécanisme d’inhibition interfaciale caractéristique de ces macrolactones bicycliques
Brefeldin A (BFA) is a macrocyclic lactone first isolated from Penicillium decumbens in 1958. Early studies showed that BFA exhibits a wide range of biological activities including the inhibition of proteins transport from the endoplasmic reticulum to the Golgi apparatus. BFA acts in a specific and unusual manner following an interfacial inhibition process (BFA recognizes both a small G protein and its protein effector) that could inspired new conceptions for drug design. The utility of BFA is hampered however by its toxicity so that the synthesis of active, but less toxic, analogues, is highly desirable. We report herein on the total synthesis of 15-nor-Me-BFA along with its C4 epimer (4-epi-15-nor-Me-BFA) following a strategy that was previously developed in our laboratory for the synthesis of BFC, the non-hydroxylated analogue of BFA at carbon C7. These two analogues have been prepared in 24 steps in a 2. 9 % overall yield. The results of biochemical tests, realized on both BFA and its synthetic analogues, have allowed us to better understand the mode of action of these bicyclic macrolactones
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8

Chemburkar, Kirti. "Performance of BFSA Based Anti-Collision Protocols for RFID Networks Supporting Identical Tags." UNF Digital Commons, 2011. http://digitalcommons.unf.edu/etd/124.

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Radio Frequency Identification (RFID) is a powerful emerging technology widely used for asset tracking, supply chain management, animal identification, military applications, payment systems, and access control. Over the years, RFID has emerged as a popular technology in various industries because of its ability to track moving objects. As RFID is becoming less expensive and more robust, many companies and vendors are developing tags to track objects. Multiple vendors manufacture RFID tags worldwide. Therefore, it is quite possible that they manufacture tags with the same identification code (ID) as vendor ID code data sets may not be synchronized or may be subject to tag id errors. Due to this drawback, there is the possibility that non-unique tags exist along with unique tags in the same RFID system. As existing implementations optimize the performance of RFID systems performance based on the assumption of unique tags, it is important to study the effect of non-unique tags on RFID systems. This thesis focuses on a formal analysis of the Basic Frame Slotted ALOHA (BFSA) Muting RFID system with non-unique tags. An RFID network was modeled with OPNET Modeler 14.5. An evaluation model was built to measure the total census delay, optimal frame size, and network throughput for an RFID network based on a BFSA protocol for non-unique tags and support for muting. The evaluation results are in agreement with results obtained from the evaluation of a similar model for unique tags [Kang08]. Comparing total census delay for unique and non-unique tags for variable frame sizes showed an increase in total census delay with an increase in the number of tags. Comparing minimum network throughput, mean network throughput, and maximum network throughput for unique and non-unique tags for variable frame sizes showed a decrease in network throughput with an increase in the number of tags.
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9

Mazzucato, Nicolo' <1992&gt. "PSO and BFO: two alternative metaheuristics for portfolio optimization problem." Master's Degree Thesis, Università Ca' Foscari Venezia, 2019. http://hdl.handle.net/10579/14538.

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As part of Modern Portfolio Theory, Portfolio management is a subject introduced by Markowitz back in 1950s. In Chapter 1 of this paper, we describe the Mean- Variance portfolio selection model proposed by Markowitz. Since its introduction, this model has been considered as the standard model. Although it has many advantages, with the years passing and the increased complexity of the markets, the model showed all its limits. The main drawbacks arises from the unrealistic assumptions at the base of the model. In other words, the assumptions are not able to present the real world and the risk measure used. Therefore, there was the need of a new class of risk measures, coherent risk measure, suitable for financial portfolios. The coherent measure of risk that belongs to this class chosen for this paper is the two-sided risk measure introduced by Chen and Wang in 2008. Chapter 2 describes the metaheuristics and in particular focuses on those chosen for this paper. Metaheuristic can be describe as trial and error optimization techniques able to find high level solutions to complex problems. Those high-level solutions, although high quality solutions, are not the optimal ones. However, metaheuristics find good solutions in a reasonable amount of time. In this paper we decided to choose bio-inspired metaheuristics, in particular Particle Swarm Optimization and Bacterial Foraging Optimization. In Chapter 3 we presented an alternative model to the one introduced by Markowitz, that is the realistic portfolio proposed by Corazza, Fasano and Gusso. This strategy allows to make the analysis more realistic by overcoming the limits of the model described in Chapter 2. However, in order to effectively solve the NP-hard problem that arises from the use of the two-sided risk measure combined with the realistic portfolio chosen, we applied an exact penalty method, which allows to transform the constrained problem into an unconstrained one. Finally, in Chapter 4, we applied PSO and BFO to solve the portfolio selection problem presented in the previous chapter. For this application, the data used are the daily closing prices of DAX 30 index from March 2014 to November 2018. The periods considered are eight, and each one consists of 8 in-sample months and 3 out-of-sample. In addition, we also analyzed the respect of the monotonicity property of the risk measure. Lastly, we carried out a comparison between the given respectively between PSO and BFO.
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10

Bhogal, Varun. "Analysis of BFSA Based Anti-Collision Protocol in LF, HF, and UHF RFID Environments." UNF Digital Commons, 2014. http://digitalcommons.unf.edu/etd/511.

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Over the years, RFID (radio frequency identification) technology has gained popularity in a number of applications. The decreased cost of hardware components along with the recognition and implementation of international RFID standards have led to the rise of this technology. One of the major factors associated with the implementation of RFID infrastructure is the cost of tags. Low frequency (LF) RFID tags are widely used because they are the least expensive. The drawbacks of LF RFID tags include low data rate and low range. Most studies that have been carried out focus on one frequency band only. This thesis presents an analysis of RFID tags across low frequency (LF), high frequency (HF), and ultra-high frequency (UHF) environments. Analysis was carried out using a simulation model created using OPNET Modeler 17. The simulation model is based on the Basic Frame Slotted ALOHA (BFSA) protocol for non-unique tags. As this is a theoretical study, environmental disturbances have been assumed to be null. The total census delay and the network throughput have been measure for tags ranging from 0 to 1500 for each environment. A statistical analysis has been conducted in order to compare the results obtained for the three different sets.
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Rizzo, Michael <1992&gt. "PSO e BFO per la gestione di hedge funds: il caso DeltaHedge." Master's Degree Thesis, Università Ca' Foscari Venezia, 2018. http://hdl.handle.net/10579/13804.

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L'obiettivo del presente lavoro è quello di risolvere un reale problema di ottimizzazione vincolata che mi è stato proposto durante lo stage svolto presso la società DeltaHedge. In particolare, mi è stato chiesto di determinare l'allocazione ottima di un determinato capitale all'interno del programma Styx, il quale investe in 9 strategie di trading contrarian su FX futures. Per la risoluzione di tale problema sono state utilizzate due metaeuristiche bio-ispirate: la Particle Swarm Optimization (PSO) e la Bacterial Foraging Optimization (BFO).
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12

Chan, Mei-lan, and 陳美蘭. "Notions of language dominance, language preference and language choicein the study of bilingual first language acquisition (BFLA)." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45163893.

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13

Du, Nan. "Beyond "More than Moore": Novel applications of BiFeO3 (BFO)-based nonvolatile resistive switches." Doctoral thesis, Universitätsbibliothek Chemnitz, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-202508.

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The size reduction of transistors has been the main reason for a successful development of semiconductor integrated circuits over the last decades. Because of the physically limited downscaling of transistors, alternative technologies namely the information processing and nonvolatile resistive switches (also termed memristors) have come into focus. Memristors reveal a fast switching speed, long retention time, and stable endurance. Nonvolatile analog bipolar resistive switching with a considerable large On/Off ratio is reported in BiFeO3 (BFO)-based resistive switches. So far resistive switches are mainly applied in memory applications or logic operations. Given the excellent properties of BFO based memristors, the further exploration of functionalities for memristive devices is required. A new approach for hardware based cryptographic system was developed within the framework of this dissertation. By studying the power conversion efficiencies on BFO memristor at various harmonics, it has been shown that two sets of clearly distinguishable power ratios are achievable when the BFO memristor is set into high or into low resistance state. Thus, a BFO-based binary encoding system can be established. As an example the unrecoverable seizure information from encoded medical data suggests the proper functioning of the proposed encryption system. Aside from cryptographic functionality, the single pairing spike timing dependent plasticity (STDP) in BFO-based artificial synapses is demonstrated, which can be considered as the cornerstone for energy-efficient and fast hardware-based neuromorphic networks. In comparison to the biological driven realistic way, only single one pairing of pre- and postsynaptic spikes is applied to the BFO-based artificial synapse instead of 60-80 pairings. Thus, the learning time constant of STDP function can be reduced from 25 ms to 125 us
In den letzten Jahrzehnten war die Größenreduktion von Transistoren einer der Hauptgründe für die Leistungssteigerung von integrierten Halbleiterschaltungen. Aufgrund des physikalisch beschränkten Skalierungspotentials, werden alternative Technologien für Halbleiterschaltungen entwickelt. Dazu zählen neuartige Widerstandsschalter, sogenannte Memristoren, welche wegen ihrer schnellen Schaltgeschwindigkeit, langen Speicherzeit und stabilen Haltbarkeit in den Fokus der Forschung gerückt sind. Das nichtflüchtige analoge bipolare Schalten des Widerstandwertes mit einem On/Off Verhältnis größer als 100 wurde in BiFeO 3 (BFO)-basierten Widerstands-schaltern beobachtet. Bisher wurden Widerstandsschalter hauptsächlich als Speicher oder in rekonfigurierbaren Logikschaltungen verwendet. Aufgrund der ausgezeichneten Eigenschaften von BFO-basierten Memristoren, ist die Untersuchung weiterer neuer Funktionalitäten vielversprechend. Als neuer Ansatz für ein Hardware-basiertes Kryptosystem wird in der vorliegenden Arbeit die Ausnutzung des Leistungsübertragungskoeffizienten in BFO Memristoren vorgeschlagen. Mit Hilfe der unterschiedlichen Oberschwingungen, welche von einem BFO Memristor im ON und OFF Zustand generiert werden, wurde ein Kryptosystem zum Kodieren binärer Daten entwickelt. Ein Test des Hardware-basierten Kryptosystems an Biodaten ergab, dass die kodierten Biodaten keine vorhersagbare Korrelation mehr enthielten. In der vorliegenden Arbeit wurden darüberhinaus BFO-basierte künstliche Synapsen mit einer Aktionspotentials-Intervall abhängigen Plastizität (STDP) für Einzelpulse entwickelt. Diese Einzelpuls-STDP legt den Grundstein für energieffiziente und schnelle neuromorphe Netzwerke mit künstlichen Synapsen. Im Vergleich zu biologischen Synapsen mit einer 60-80-Puls-STDP und einem Lernfenster auf der ms-Zeitskale, konnte das Lernfenster von BFO-basierten künstlichen Synapsen von 25 ms auf 125 μs reduziert werden. Solch ein schnelles Lernen ermöglicht auch die extreme Reduzierung des Leistungsverbrauchs in neuromorphen Netzwerken
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HENRIQUES, João Paulo Carvalho. "Sistema de Controle Preditivo Multimodelos Fuzzy TS-BFO embarcado em um Controlador Lógico Programável." reponame:Repositório Institucional da UNIFEI, 2014. http://repositorio.unifei.edu.br:8080/xmlui/handle/123456789/303.

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Made available in DSpace on 2016-01-26T12:21:55Z (GMT). No. of bitstreams: 1 dissertacao_henriques_2014.pdf: 9149740 bytes, checksum: 9212df54268d0b66cf8ba4058e3ed7e3 (MD5) Previous issue date: 2014-08
Este trabalho aborda o problema da identificação e controle de sistemas industriais não-lineares através de um algoritmo de controle preditivo que utiliza multimodelos lineares. Algoritmos de controle preditivo baseados em modelos (MBPC - Model Based Predictive Controller) utilizam o modelo do processo para a determinação do conjunto de previsões de saída e desta forma determinar qual a ação de controle ótima a ser adotada. Neste contexto, a proposta deste trabalho é implementar um sistema de controle preditivo em um controlador lógico programável (CLP), utilizando para a representação dos sistemas não-lineares modelos fuzzy Takagi-Sugeno (TS) com base de funções ortonormais nos consequentes das regras. As bases de funções ortonormais apresentam características estruturais interessantes para representação de sistemas dinâmicos, com destaque para a ausência de realimentação de saída, característica de suma importância em algoritmos de controle preditivo. Dentre as bases de funções ortonormais utilizadas na modelagem de sistemas dinâmicos, destacam-se as bases de funções ortonormais generalizadas (GOBF) com funções internas em estrutura Ladder. Com a utilização de tais funções o sistema dinâmico sob análise é parametrizado utilizando somente valores reais, independente da natureza de seus polos. Os modelos fuzzy TS-GOBF neste trabalho são obtidos através de amostras da entrada e saída do sistema. Os antecedentes das regras fuzzy são determinados através da técnica de agrupamento fuzzy (fuzzy clustering), sendo o número ideal de grupos obtido através de critérios de avaliação de agrupamento fuzzy. Os parâmetros dos consequentes das regras, formados por GOBFs, são inicialmente obtidos utilizando-se o método dos mínimos quadrados locais. Determinados os modelos fuzzy TS-GOBF inicial, são utilizadas técnicas de simplificação da base de regras fuzzy e um algoritmo para a otimização dos parâmetros do modelo TS-GOBF, como as funções de pertinência nos antecedentes das regras e os parâmetros nos consequentes. Obtido o modelo fuzzy TS-GOBF otimizado, os controladores preditivos lineares que atuarão nos modelos locais são embarcados no CLP, juntamente com a base de regras fuzzy e com os parâmetros das GOBFs. A ação de controle global é obtida através da combinação ponderada das ações dos controladores locais. A cada ciclo do CLP a ação de controle global é atualizada e aplicada no processo sob controle. A abordagem proposta neste trabalho apresenta vantagens com relação a outras metodologias de controle não-linear utilizadas na indústria, uma vez que o sistema de controle em questão pode ser implementado em CLPs comerciais de baixo custo utilizando a linguagem Texto Estruturado. Para ilustrar a proposta dessa dissertação, são apresentados, no final deste trabalho, exemplos de modelagem e controle de processos reais.
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Elagab, Omer Yousif. "The legality of non-forcible counter-measures in international law." Thesis, University of Oxford, 1986. https://ora.ox.ac.uk/objects/uuid:bbb45168-8338-447a-bf4a-fe4e47834e3e.

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The object of this thesis is to examine the legality of nonforcible counter-measures in bilateral contexts. The major questions addressed are as follows: (i) do counter-measures constitute an autonomous category of justification for wrongful conduct? (ii) if so, what are the conditions of the legality of that category? (iii) what are the more significant collateral constraints on the legality of countermeasures? and (iv) what is the extent to which policy considerations contribute towards the determination of the legality of counter-measures? The study begins with an Introduction which indicates the scope and the outline of the thesis, the terminology employed, and the approach adopted. Chapters One and Two deal with the historical development of the law of reprisals with special reference to non-forcible counter-measures. Chapter Three is entitled "The status of non-forcible counter-measures in customary international law since 1945: a preliminary sketch". Chapters Four, Five,and Six are devoted to examining the conditions of the legality of non-forcible counter-measures, viz., (i) breach, (ii) prior demand for reparation; and (iii) proportionality. Chapter Seven examines some of the more significant collateral constraints on the legality of counter-measures. In Chapter Eight an attempt will initially be made to examine the circumstances in which the performance of obligations under a treaty may be withheld as a counter-measure. The conclusions reached will then be compared and contrasted with the regime established by the Vienna Convention on the Law of Treaties. Chapter Nine considers the legality of counter-measures in the context of a commitment to peaceful settlement. Chapter Ten is concerned with the legality of economic coercion, and also with whether the legality of that concept has a bearing on the question of lawful counter-measures. The final Chapter summarises the major characteristics of the existing legal regime of counter-measures.
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16

Sunderland, A. M. "Fibrewise CoHopf spaces." Thesis, University of Oxford, 1992. http://ora.ox.ac.uk/objects/uuid:d8d5d5d3-e761-46af-bf6a-d0b70a2007e4.

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A fibrewise coHopf space X over a base B is a sectioned space for which the diagonal map X —> X x BX may be compressed into X VBX up to fibrewise pointed homotopy. Such spaces have been investigated by I. M. James in the case where X is a sphere bundle over a sphere. The purpose of this thesis is to demonstrate some of the properties of fibrewise coHopf spaces over more general bases. Particular attention is given to sphere bundles and fibrations with spherical fibre. The fibrewise reduced suspension of a sectioned fibrewise space with closed sec- tion is fibrewise coHopf with associative comultiplication (up to fibrewise pointed homotopy) and a fibrewise inversion. Examples of fibrewise coHopf spaces not of this form are exhibited, and sufficient conditions are given to ensure that a fibrewise coHopf space has the primitive fibrewise pointed homotopy type of a fibrewise re- duced suspension, in terms of the dimension and connectivity of the space, its base and the fibres. It is shown that these conditions may be relaxed if the fibrewise coHopf structure on the space is assumed to be homotopy-associative. An example of a non-associative fibrewise coHopf sphere bundle is given. It is shown that, if q > 1 is odd, a sectioned orientable q-sphere bundle over a finite connected complex is fibrewise coHopf if and only if its fibrewise localisation at the prime 2 is fibrewise coHopf. Moreover, the fibrewise rationalisation of an odd-dimensional sphere bundle over a finite polyhedron whose fibrewise unreduced suspension is fibrewise coHopf is shown to be a trivial fibration. As an application, it is shown that new fibrewise coHopf spherical fibrations may be constructed by mixing. The Thorn space is used to determine the cohomology ring of the total space of a fibrewise coHopf sphere bundle in terms of that of its base, and a generalised Hopf invariant is constructed which vanishes on fibrewise coHopf sphere bundles.
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Heymans, Catherine. "Weak gravitational lensing and intrinsic galaxy alignments." Thesis, University of Oxford, 2003. http://ora.ox.ac.uk/objects/uuid:c86f8783-47b1-4cd0-bffa-0bc948b67974.

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This thesis describes an investigation into weak gravitational lensing, a unique and powerful astronomical tool for the study of dark matter on large scales. Lensing distorts background images, inducing correlations in the observed ellipticities of galaxies, and these correlations can be used to estimate many characteristics of the Universe. Key to all weak lensing studies is a reliable and unbiased method to detect weak lensing distortions from observed galaxy images that are contaminated by Earth and telescope-based shearing and smearing distortions. A new galaxy model-fitting technique is presented that has been developed in order to satisfy this requirement, which will also permit future signal-to-noise optimised measurements of weak lensing shear. Model-fitting provides a good alternative to the standard scite{KSB} method (KSB), and comparisons between the two techniques are drawn from an analysis of deep {it R} band imaging from the COMBO-17 survey, revealing strong evidence for the presence of bias in KSB galaxy shape measurement. With the galaxy model-fitting technique, an investigation into the effectiveness of the Oxford Dartmouth Thirty degree survey (ODT) for gravitational lensing studies is presented, resulting in the detection of weak gravitational lensing by large scale structure, or `cosmic shear', in 0.7 square degrees of the best seeing ODT images. One concern for all cosmic shear studies is that the weak lensing signal, manifest in the weakly correlated ellipticities of distant galaxies, is contaminated by the intrinsic alignment of close galaxy pairs, potentially induced during galaxy formation by physical interactions such as tidal forces. This contamination is investigated theoretically, through numerical simulations, and observationally, with an analysis of the COMBO-17 survey and the study of published results from the Red-sequence Cluster survey and the VIRMOS-DESCART survey, concluding that the intrinsic alignment effect is at the lower end of the range of theoretical predictions. The impact of intrinsic galaxy alignments on cosmological parameter estimation is investigated, with an analysis of the weak lensing results from the COMBO-17 survey. When marginalising over the observationally constrained intrinsic alignment signal, the amplitude of the matter power spectrum sigma_8 is reduced by ~0.03 to sigma_8(Omega_m / 0.27)^{0.6} = 0.71 pm 0.11, where Omega_m is the matter density parameter. With distance information from either spectroscopy or photometric redshifts, the down-weighting of nearby galaxy pairs in weak lensing analysis can be optimised to virtually eliminate the systematic errors in the shear signal arising from intrinsic galaxy alignments, leaving a much smaller, largely statistical error. This method is applied to the photometric redshift sample of the COMBO-17 survey. Weak lensing measurements from the forthcoming SuperNova/Acceleration Probe weak lensing survey (SNAP), and the Canada-France-Hawaii Telescope Legacy survey, are expected to be contaminated on scales >1 arcminute by intrinsic alignments at the level of ~ 1% and ~2% respectively. Division of the SNAP survey for lensing tomography significantly increases the contamination in the lowest redshift bin to ~7% and possibly higher. Removal of the intrinsic alignment effect by the downweighting of nearby galaxy pairs will therefore be vital for the lensing tomography studies of SNAP.
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18

Rodriguez, Lopez Juan-Pablo. "The possibility of social critique : between critical social theory and social movements." Thesis, University of Bristol, 2018. http://hdl.handle.net/1983/2d7edd90-e0d7-498b-bf1a-6fc0d727b5a8.

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The global wave of mobilisations that took place after the 2008 financial crisis prompted social movement scholars and radical thinkers to highlight the ability of social actors to resist capitalism and develop new forms of radical democracy. This initial moment of 'effervescence' has been followed by a longer period of balance and critical evaluation. In this context, critical theorists have welcomed the renewal of social critique after a long period of withdrawal and the enunciation of a post-critical era. However, this renewal has taken place at the expense of critical theory's social significance. In this work, I propose a productive cross-fertilisation of the various realms in which the social critique of capitalism has (separately) taken place: critical social theory and practices of social criticism carried out by social movements. Drawing on Fredric Jameson's notion of an 'aesthetic of cognitive mapping' and on Luc Boltanski's critical sociology, the thesis argues that the affinities between the two forms of critique provide a basis upon which a politically and theoretically productive articulation might be built. In the first part, I explore four different styles of theoretical critique - from David Harvey to Luc Boltanski - highlighting their merits and limitations. In the second part, I delve into the practices of criticism of capitalist society carried out by two Chilean social movements: the pobladores' movement and the student movement, respectively, in order to explore how social critique is performed in the context of concrete social struggles. Pobladores and students have been resisting, mapping, and contesting neoliberal policies in Chile since the beginning of the 2000s, actualising old practices of resistance in a new and fragmented social context. By disclosing the affinities between the practices of social critique at both levels, I contend that critical theorists can learn from social movements' descriptions and explanations, and thus rehabilitate its political emancipatory dimension.
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19

Prabhakar, Rahul. "Varieties of regulation : how states pursue and set international financial standards." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:eba01ce6-e081-447e-bf2a-73790e83c916.

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What explains the form and substance of international financial standards? Form refers to the legal or non-legal bindingness of an international standard. Substance refers to how significantly the standard changes the international status quo. The form and substance of international standards on bank capital adequacy, hedge funds, “bail-in” resolution, and insurance capital adequacy challenge the predictions of major rationalist, realist, and two-level perspectives. I propose a novel theory and present original evidence to test two central claims. First, the structure of domestic institutions and strategic interaction within a state incentivizes an actor from that state to prefer and pursue a certain form of international standard: legally or non-legally binding. The state actor, as a first mover, aims to propose a standard at an appropriate international institution which produces standards of its preferred form. Second, the state actor must bargain with representatives of other states according to certain decision-making rules at the international standard-setting institution. The type of decision-making rule used in bargaining—not the market power or other characteristics of key players—explains the substance of the final standard. More restrictive decision-making rules, which use majority or supermajority voting, lead to greater change than open rules, which are based on consensus or unanimity voting. My empirical findings remove the veneer of technocratic legitimacy associated with international standard-setting to reveal intense distributional battles. In pursuing the Basel capital standards, the US Federal Reserve has been motivated more by turf wars with other US bank regulators than by its publicly stated desire to create a “level playing field” for internationally active banks. Supported by domestic collaboration between regulators and industry, French officials set a legally binding and deep de facto international standard for hedge fund managers over the vigorous objections of the City of London. By pursuing a soft standard on bail-in, the Bank of England has sought not only to protect taxpayers from costly bailouts, but also to keep Her Majesty’s Treasury at arm’s length. The lack of international insurance regulation is due not to the lack of effort by the UK Financial Services Authority and its European partners, but to open decision-making rules that allow US state regulators, albeit fragmented and under-resourced, to protect the international status quo. In each of these cases, I specify how domestic and international institutional settings provide enduring opportunities and constraints for key players in global finance.
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20

Winship, Paul Colin Michael. "The development and applications of the Lewis acid-mediated osmium-catalysed oxidative cyclisation." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:e4c42be0-bfea-451f-8af3-890b141423c9.

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The acid-mediated osmium-catalysed oxidative cyclisation of 1,2-diols bearing a pendent alkene has been shown to be a powerful method for the formation of cis-2,5-disubstituted tetrahydrofurans. This thesis describes the development of this methodology to broaden the scope of the general reaction, followed by applying the oxidative cyclisation to the synthesis of tetrahydrofuran containing natural products. Introduction: This section reports a range of ractions that osmium oxo-species will facilitate, namely the formation of carbon-oxygen and carbon-nitrogen bonds in a selective manner. In addition to this a variety of similar metal-mediated oxidative cyclisations are discussed. Results and Discussion: The process for optimising the oxidative cyclisation is documented, along with examples which directly compare newly developed methodology with existing methodology. The incorporation of a catalytic amount of a Lewis acid is shown to be more effective than using an excess of a Brønsted acid, with osmium catalyst loading being reduced to 0.2 mol%. Subsequently, this methodology is shown to facilitate the successful oxidative cyclisation of vinyl silanes to form silyl-substituted tetrahydrofurans, along with methodology to “unmask” the silane, as a potential route to lactols. Finally, the application of this methodology to synthesis is demonstrated, with the successful synthesis of neodysiherbaine A being achieved in 7 steps and the C21-30 fragment of pectenotoxin-4 in 12 steps.
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21

Hung, Ying-Lin. "Sourness, sweetness, bitterness and spiciness : diaspora narratives and shifting identites amongst Taiwanese people living in the UK." Thesis, University of Bristol, 2010. http://hdl.handle.net/1983/47e77fff-dd43-417c-bf5a-91475fdb9389.

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The sense of my shifting diasporic identity prompted a curiosity about how other Taiwanese diaspora change their identities. In order to unravel the mysterious identity shifting, I recruited a group of Taiwanese people, who have lived in the UK for various reasons for three years minimum, from the internet and real life to conduct my study. By using the methodology of collective biography/collective memory-work, which is developed from Germany, Australia then to the UK, and from German to English, my participants are required to have literacy skills of English and Chinese. After four workshops of doing collective memory-work, I had collected stories of four different environmental settings of the workshops, the writings from all participants and email exchanges amongst us. To make the diaspora narratives more complete, I supplemented my autoethnography with the collective biography. This study focused on two main factors - language and culture. Linguistics, however, was excluded in this case, and alternatively, I drew attention to how the relation between language proficiency and self confidence impacted upon our diasporic identities. In addition, I also explored the relationship between writing and identity, which played a crucial role in collective biography, even the whole study. As this was a participant-oriented study, under the big umbrella of culture, I chose certain aspects that had been stressed during the workshops. Our awareness of cultural difference had been shown in food, space, weather, greetings, attitudes and values, which all affected our diasporic identities in terms of emotional, cultural and geographical displacement. In the last chapter, I inspected my reflexive musing about the whole study and thoughts about the feasibility of collective biography for Taiwanese people in the future.
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22

Bregman, Tom P. "The impacts of human land-use change on avian diversity and associated ecosystem functions." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:b0364847-0949-4d9f-bf2a-2cca62a988a7.

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Understanding the impacts of land-use change on biodiversity and the ecosystem services that it provides is of great importance given unprecedented growth of the human population. Past studies attempting to explore these impacts have described the overall structure of communities (i.e. species richness and trait diversity) across gradients of local scale degradation and fragmentation, and have sought to identify whether the loss of species following land-use change is non-random. Yet, despite a wealth of research we still lack a generalised understanding of how land-use change impacts on traits responsible for determining species sensitivity and their role within ecosystems, particularly for vertebrates. Moreover, despite the importance of niche-based processes in the assembly of communities, we have not yet elucidated whether these are important in mediating the collapse of communities in human-dominated landscapes. To fill these existing research gaps, I collated comprehensive avian species inventories from fragmented and degraded forests and compared their structure with communities existing in continuous forests. In Chapter 2, I tested whether sensitivity of species to forest fragmentation varies between the temperate zone and the tropics and whether there are key differences in the size of fragments required to maintain ecosystem processes in these regions. I found that sensitivity to fragmentation varies according to functional group and body mass, with the prevalence of insectivores and large frugivores declining in relation to fragment size, particularly in tropical fragments smaller than 100 ha. In Chapter 3, I tested whether functional diversity and the mean position of trait diversity of insectivores and frugivores, changed across a gradient of intensifying land-use change. I found a decline in the functional diversity of forest species and a shift in the mean community traits for both forest and non-forest species. In Chapter 4, I tested whether the structure of tropical bird communities are influenced by species interactions in a fragmented landscape. I found increasing over-dispersion in functional and phylogenetic trait relatedness among species with decreasing fragment size, suggesting that competitive interactions are important in the disassembly of avian communities. In Chapter 5, I modelled the impact of forest cover change on ecosystem function across the Brazilian Amazon, focusing on seed dispersal by birds. Furthermore, I tested whether ecosystem function declined linearly with decreased forest cover after accounting for differences in the underlying pools of species. I found the lowest levels of functional diversity along the southern arc of deforestation and that the dispersal of large seeds showed some resilience to declining forest cover. Taken together, my results suggest that the loss of species from communities in degraded and fragmented landscapes is strongly non-random. Insectivores and large frugivores are most sensitive to land-use change, with species located in the densest parts of trait space being most threatened by a decline in forest patch size, suggesting that species interactions regulate the collapse of avian diversity in human-modified forests. I conclude that land-use change has important implications for the provisioning of ecosystem services, including seed dispersal and the control of insect herbivores. The impact of future land-use change is likely to be mediated by the composition of the original pool of species and the amount of redundancy in the ecosystem services that they provide. I discuss the relevance of my findings to land-use management strategies and policy interventions, and in particular conclude that these should, where possible, maintain pristine forest patches above 1000 ha, improve connectivity among habitat patches, and ensure greater protection for logged and burnt forests. Future studies should focus on clarifying the link between shifts in vertebrate community structure and the functioning of forest ecosystems.
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23

Champion, Clement Henry Martin. "The genetic control of microtubule-mediated tip-growth stability in the liverwort Marchantia polymorpha." Thesis, University of Oxford, 2017. http://ora.ox.ac.uk/objects/uuid:c693ef49-3733-4577-bf6a-86429248467b.

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Polar growth is an important mechanism for plant cell morphogenesis. Tip-growth represents an extreme mode of polar growth where cell expansion is stably restricted to a narrow domain of the cell periphery resulting in the formation of a tubular cell projection. The microtubule cytoskeleton controls the stable positioning of the growth region in tip-growing cells of flowering plants and mosses. I show that this holds true in the earliest diverging clade of land plants, the liverworts. In Marchantia polymorpha, pharmacological destabilization of the microtubule cytoskeleton leads to the formation of wavy or bifurcating rhizoids, a tip-growing cell type analogous to root hairs of flowering plants and to caulonema cells of mosses. Characterization of the organisation of the microtubule cytoskeleton in growing rhizoids of Marchantia polymorpha revealed longitudinally oriented microtubules that grow towards and converge into the apical dome. Because microtubule-associated proteins (MAPs) control the organisation of the microtubule cytoskeleton I generated the first de novo genome assembly of Marchantia polymorpha and compared the MAP repertoire of the liverwort model with that of existing model organisms of the green lineage. A mutant screen in Marchantia polymorpha identified the function of MpWAVE DAMPENED LIKE (MpWDL) and MpNIMA-RELATED KINASE (MpNEK) in microtubule-mediated tip-growth stability. MpWDL localizes preferentially to microtubules in the shank of growing rhizoids, where it promotes the longitudinal orientation of the microtubule cytoskeleton. These results are discussed in the context of the evolution of microtubule-mediated tip-growth stability and the tentative hypothesis that the underlying mechanism differs between flowering plants and bryophytes is proposed.
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24

Theophilo, Klara Rhaissa Burlamaqui. "Estudo das propriedades dielétricas e magnéticas da matriz compósita: SrBi2Nb2O9(SBN)X-BaFe12O9(BFO)1-X." reponame:Repositório Institucional da UFC, 2011. http://www.repositorio.ufc.br/handle/riufc/19952.

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THEOPHILO, K. R. B. Estudo das propriedades dielétricas e magnéticas da matriz compósita: SrBi2Nb2O9(SBN)X-BaFe12O9(BFO)1-X. 2011. 104 f. Dissertação (Mestrado em Física) - Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2011.
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In this work we studied the properties of composites based in M-type barium hexaferrites BFO (BaFe12O19) and ferroelectric ceramic SBN (SrBi2Nb2O9). M-type barium hexaferrites (BaFe12O19) come out as a new alternative for the low cost production of ferrofluids, magnetic record media and sensors. Some of its characteristics are high magnetic saturation, high coercivity and good resistance to corrosion. Besides, the SBN (SrBi2Nb2O9) is a ceramic with uncountable applications in devices where ferro-piezoeletrics materials are needed. This material shows a good fatigue resistance, being one of the most liable substitutes for the Lead Zirconate Titanate (PZT) in the ferroelectrics random access memory (FERAM). The magneto-dielectric matrix composite (SrBi2Nb2O9)x(BaFe12O19)100-x, where x stands for 0,25,50,75 and 100 wt% were prepared by a new procedure in the solid state route. Also, it was done a study in the effects of a group of organic (TEOS, PVA and glycerin) binders in the structural properties of the ceramic matrix composites. The composite was analyzed with X-ray diffraction, Raman and Infrared spectroscopy, Mössbauer spectroscopy and scanning electron microscope (SEM) for a better understanding of the microstructural properties. Radiofrequency (RF) dielectric measurements and Impedance analysis, magnetic and electric hysteresis loops, microwave dielectric measures and monopole antenna measures and simulation are discussed as well.
Nesse trabalho, estudamos as propriedades da matriz compósita baseada na hexaferrita de bário do tipo M BFO (BaFe12O19) e da cerâmica ferroelétrica SBN (SrBi2Nb2O9). As hexaferritas de bário do tipo M despontaram como uma nova opção para a produção de baixo custo de ferrofluidos, meios de gravação magnética e sensores. Algumas de suas características são alta magnetização de saturação, alta coercividade e boa resistência à corrosão. Além disso, o SBN (SrBi2Nb2O9) é uma cerâmica com incontáveis aplicações em dispositivos onde materiais ferro-piezoeletricos são necessários. Esse material apresenta uma boa resistência à fadiga sendo um dos principais substitutos do Titanato Zirconato de Chumbo (PZT) nas memórias ferroelétricas de acesso aleatório (FERAM’s). A matriz cerâmica magneto-dielétrica (SrBi2Nb2O9)x(BaFe12O19)100-x, onde x = 25, 50, 75 e 100% do peso, foi preparada pela rota de estado sólido, com moagem e calcinação. Também, foi feito um estudo do efeito de um grupo de ligantes orgânicos (TEOS, PVA, Glicerina) nas propriedades estruturais do material. O compósito foi analisado com difração de raios-X, espectroscopia Raman e do infravermelho, espectroscopia Mössbauer e Microscopia eletrônica de Varredura, para uma melhor compreensão das propriedades estruturais do material. Medidas dielétricas na região de radiofreqüência e microondas, bem como histereses elétricas e magnéticas foram realizadas. Espectroscopia de impedância com variação de temperatura, medidas e simulação de antenas monopolo também foram estudadas nesse trabalho.
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25

Nish, Adrian. "Studies on optical characterisation of carbon nanotube suspensions." Thesis, University of Oxford, 2008. http://ora.ox.ac.uk/objects/uuid:1ecd4f04-0178-4d8b-bf3a-cd6f8d744b92.

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This thesis reports studies done on single-walled carbon nanotubes (SWNTs) using optical spectroscopy as the primary investigative technique. It focuses on advances in sample preparation which have been made possible through improvements to the method of photo-luminescence excitation (PLE) mapping of nanotubes. An introduction to the field and some theoretical models are presented initially to provide a background to the experimental chapters which follow. A description of the standard procedure for sample preparation in aqueous surfactants is then followed by a detailed introduction to PLE mapping, including modeling of SWNT spectra. The next chapter discusses improvements to the sample preparation method by using organic polymer solutions instead of aqueous surfactants for suspending the nanotubes. The results show reductions in the distribution of SWNT species which are solubilised, leading to significant improvements in the resolution of the optical absorbance spectra and an increased photoluminescence yield. Two experiments which were performed on the novel polymer-SWNT systems are then described. The first shows (via PLE mapping) that energy is transfered to the SWNTs when the polymer is photo-excited. The possible mechanisms behind this, as well as the implications for using carbon nanotubes as an additive in polymer photovoltaics, are discussed. The second experiment details a recent magneto-PL study of SWNTs embedded in films produced from the polymer solutions. Here, the improved optical signatures and absence of strain at low temperatures have revealed a previously unseen high field intensity dependence. The behavior has been explained by the magnetic field induced mixing of the excitonic states.
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26

Krarup, Anders. "The lectin pathway of complement activation." Thesis, University of Oxford, 2007. http://ora.ox.ac.uk/objects/uuid:46255854-bfba-4d57-9185-3e6ed970a2db.

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The complement system is an important immune system mechanism involved in both the recognition and elimination of invading pathogens. It is activated by three different pathways: The classical pathway, which relies on binding of C1, and results in the cleavage of C4 and C2 through activation of C1r and C1s; the alternative pathway that relies on the spontaneous hydrolysis of C3 and the lectin pathway. The lectin pathway is activated by binding of Mannan-binding lectin (MBL) or the ficolins (L-ficolin, H-ficolin and M-ficolin) to microbial binding motifs, and the subsequent activation of the MBL-associated serine proteases (MASP) 1/ 2/ 3. Of these MASP2 has been identified as the enzyme responsible for the activation of complement by C4 and C2 cleavage. The work presented here will focus on four different aspects of the lectin pathway: specificity and stoichiometry of the L-ficolin protein complex, expression of H-ficolin, substrate characterization for MASP1 and investigation of the prothrombin activation potential of MASP2. L-ficolin binding specificity was investigated using glycan array technology, and it was found that L-ficolin, instead of recognizing single monosaccharides like MBL, instead binds to extended oligosaccharide structures. The binding to these was dependent not only on the presence of acetyl groups, but also on their orientation in space. It was also found that L-ficolin in serum is found as a multimeric protein complex composed of 18 polypeptide chains and associated with one MASP dimer. The expression of H-ficolin resulted in the generation of a stable mammalian cell line producing oligomerized and biologically functional H-ficolin. MASP1 substrate specificity was investigated by two different procedures. Firstly fractionated plasma was subjected to MASP1 treatment in an attempt to identify a plasma protein substrate. This did not yield any substrate candidates, since only cleavage of the protease inhibitor α-2-macroglobulin could be detected. Additionally the thrombin-like activity of MASP1 was investigated through cleavage experiments done with factor XIII and fibrinogen. These experiments showed that the factor XIII cleavage site for MASP1 and thrombin is identical. This was also found for the fibrinogen β-chain but not for the α-chain showing that MASP1 interaction with fibrinogen is distinct from that of thrombin. An earlier observation that MASP2 was capable of activating prothrombin and generating thrombin was further characterized. Here it was shown that the activation of prothrombin by MASP2 is identical to that by factor Xa, which is the enzyme undertaking this role in the coagulation system, and that the activation can result in deposition of fibrin on the surface upon which MASP2 is bound. The prothrombin activation potential of MASP2 was also utilized to develop a new MASP2 activity assay, which was shown to be capable of measuring MASP2 activity, when MASP2 is bound, via MBL (or L-ficolin) to appropriate surfaces.
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27

Bäumer, Dirk. "Functional genetic analysis of motor neuron disease." Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:859016f8-5eff-4a8e-bfda-48afb8695646.

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Amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA) are the commonest motor neuron diseases of adult- and childhood onset. Alterations of the RNA binding protein TDP-43 are associated with most cases of ALS, while SMA is caused by deletion of the Survival Motor Neuron (SMN1) gene. SMN has been well characterised in its role in the assembly of the cellular machinery that carries out splicing of pre-mRNA, but is thought to have other functions in RNA metabolism unrelated to pre-mRNA splicing. It is conceivable that specific aspects of RNA handling are disrupted in both SMA and ALS. A variety of genetic, molecular and neuropathological approaches were applied to investigate a potential common pathway in these diseases. The spectrum of genetic mutations underlying motor neuron disorders were explored by screening patient DNA. Cell culture and mouse models were used to test the hypothesis that altered pre-mRNA splicing causes motor neuron death. Human neuropathological specimens were examined for changes in proteins involved in RNA metabolism. The results indicate that altered pre-mRNA splicing is a late occurrence in disease and more likely to be a consequence rather than the cause of motor neuron degeneration. However, the notion that RNA metabolism is highly relevant to motor neuron diseases was strengthened by the discovery of mutations in another RNA binding protein, FUS, in cases of ALS without TDP-43 pathology. Overall the findings highlight the need to consider disruption of mRNA transport and regulation of mRNA translation in future motor neuron disease research.
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Pogna, Edgar Allan. "Phosphorylation and distribution of High-Mobility Group protein HMGN1 in the context of Immediate-Early (IE) gene induction." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:5b39d964-fd81-4534-bfba-76a32bb60f4e.

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Eukaryotic genomes are highly organized and packaged into chromatin, a complex structure formed of proteins and DNA, in which the basic repeating unit is the nucleosome. Chromatin can be arranged in condensed or relaxed structures influencing accessibility of proteins that regulate transcription, replication, recombination and repair. One class of transiently chromatin-associated proteins is the High-Mobility Group (HMG) protein family. HMG proteins are subdivided into three subgroups: HMGA, HMGB and HMGN. HMGN1, the subject of this study, is a prominent member of the HMGN (High-Mobility Group Nucleosome-binding) protein family, the only HMG proteins that specifically binds to the nucleosomes. HMGNs are maintained in dynamic balance between nucleosome-associated and nucleosome-free pools. Regulation of chromatin involves several enzymatic activities that modify specific residues on chromatin proteins, which may influence these interactions. While associated with nucleosomes, HMGNs can interfere with some modifications of histone tails. Modification of HMGN1 on specific residues and post-translational modification (PTM) of histones are concomitantly regulated by the complex signalling networks associated with the induction of immediate early (IE) genes. Induction of IE genes is associated with phosphorylation of HMGN1 which has been suggested to increase the rate of dissociation of HMGN1 from the nucleosome, thus allowing access and modification of histone tails. My research has been focused on characterizing HMGN1 isoforms present in different cellular compartments and at different time-points during IE gene induction with various stimuli, including epidermal growth factor (EGF), anisomycin (An) and 12-O-tetradecanoylphorbol-13-acetate (TPA). Furthermore, I investigated the localization of HMGN1 within the nucleus and at specific IE gene loci, especially at sites where post-translationally modified histones are localised. In my analysis only the phosphorylation at serine 6 of HMGN1 shows a correlation with gene induction. Analysis of DNA sequences from chromatin immunoprecipitation (ChIP) has shown that HMGN1 is present at equal levels in active and inactive genes. It appears that HMGN1 localization on DNA is not dictated by a particular preference for any gene elements such as promoters, exons, introns or gene termination sequences.
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Trypogeorgos, Dimitrios. "Periodically driven atomic systems." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:93785d4c-76d0-41c3-bf0a-5551108d8189.

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This thesis is concerned with a variety of topics grouped together under the general theme of periodically driven atomic systems. Periodic driving is ubiquitous in most techniques used in atomic physics, be it laser cooling, ion trapping or AC magnetic fields. An in-depth understanding of the behaviour of such systems can be provided through Floquet theory which will develop as a central theme in the following chapters. The thesis is divided in two parts: neutral atoms, and ions and biomolecules. In the first part I discuss a new 41K-87Rb mixture experiment, built during the first year of my DPhil. This species combination has some very broad and low-loss interspecies Feshbach resonances that are instrumental for carrying out the experiments discussed in the first chapter. Unfortunately, the mixture experiment had to be put aside and our attention was shifted to Time-Averaged Adiabatic Potentials (TAAPs) and how these can be extended using multiple Radio-Frequency (RF) fields. This technique opens up the way for precise interferometric measurements. Lastly, the peculiar behaviour of Modulation Transfer Spectroscopy (MTS) of 39K is investigated and a linearising transformation for four-wave mixing processes is presented. In the second part we turn our attention to charged ions and biomolecules and the techniques of ion trapping. We propose a novel technique for co-trapping charged particles with vastly different mass-to-charge ratios and thoroughly explore its consequences. The behaviour of the trap and the stability of equations with periodic coefficients in general is studied using Floquet theory. The normal modes and symmetries of the system also need to be considered in relation to the effectiveness of the sympathetic cooling of the ions. Small systems were simulated using a Molecular Dynamics (MD) approach in order to capture the effect of micromotion and other heating processes.
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Meagher, Caitlin. "Make yourself at home : dreams and realities in a Japanese sharehouse." Thesis, University of Oxford, 2018. http://ora.ox.ac.uk/objects/uuid:729fa4e2-bfda-43c5-912d-c7eff445bfd8.

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Despite the historical associations of shared living with economically and socially marginalised populations, contemporary sharehouses in Japan are seen and marketed as a new foreign lifestyle import that offers an alternative to living alone or in the family home. Based primarily on nine months of intensive fieldwork during residence in a sharehouse, interviews with sharehouse professionals, and discourse analysis of marketing materials, the present work discusses the gaps and consonances amongst the promises set forth in sharehouse marketing, my housemates' desires and expectations, and the realities of living with strangers for the first time and in the absent a template for social etiquette. The thesis considers the contemporary 'sharehouse boom' in the context of social and economic change. It considers what the desire for an experimental lifestyle indicates about young people's beliefs about their personal futures and the future of Japanese society, and considers the extent to which their desires and expectations are fulfilled.
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Ofrath, Avner. "Demarcating the cité française : exclusion and inclusion in colonial Algeria, 1870-1938." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:60b46cc6-763f-4b3b-bf6a-8357a249c2ab.

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This thesis discusses the unmaking of republican citizenship in colonial Algeria and the reverberations of this process in the metropole under the Third Republic, as well as demands and contestations by various populations in the colony concerning participation and rights. The attempt to establish a regime of privileges for settlers and to exclude the Muslim majority led politicians, jurists, and administrators to rely on religion and ethnicity as legal criteria to demarcate the boundaries of French citizenship. In their quest to legitimise the political exclusion of the Muslim population, politicians and legal experts from the late nineteenth century onwards portrayed Islam as an immobile and unmodern religion. Reiterated in mainland France whenever the demand for political reform in Algeria was raised, such theories gave rise to the widely-held view that being Muslim was inherently irreconcilable with being French. At the same time, the thesis examines colonial reform movements and moments of asymmetrical negotiation between populations in Algeria and the state on the demarcation of French citizenry. Both the naturalisation of the Algerian Jews and the backlash against it are re-interpreted here to highlight the pivotal role played by the local and the settler populations. In a similar vein, the thesis discusses debates sparked in the early twentieth century by Algerian Muslim campaigns for political rights, debates which yielded alternative visions of participation in the Republic. The failure of such attempts to accommodate religious difference on the eve of collapse of the Third Republic re-affirmed the colonial order in Algeria and the deep imprint it had left on conceptions of French citizenship.
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Du, Nan, Mahdi Kiani, Christian G. Mayr, Tiangui You, Danilo Bürger, Ilona Skorupa, Oliver G. Schmidt, and Heidemarie Schmidt. "Single pairing spike-timing dependent plasticity in BiFeO3 memristors with a time window of 25ms to 125µs." Universitätsbibliothek Chemnitz, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-171458.

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Memristive devices are popular among neuromorphic engineers for their ability to emulate forms of spike-driven synaptic plasticity by applying specific voltage and current waveforms at their two terminals. In this paper, we investigate spike-timing dependent plasticity (STDP) with a single pairing of one presynaptic voltage spike and one postsynaptic voltage spike in a BiFeO3 memristive device. In most memristive materials the learning window is primarily a function of the material characteristics and not of the applied waveform. In contrast, we show that the analog resistive switching of the developed artificial synapses allows to adjust the learning time constant of the STDP function from 25ms to 125μs via the duration of applied voltage spikes. Also, as the induced weight change may degrade, we investigate the remanence of the resistance change for several hours after analog resistive switching, thus emulating the processes expected in biological synapses. As the power consumption is a major constraint in neuromorphic circuits, we show methods to reduce the consumed energy per setting pulse to only 4.5 pJ in the developed artificial synapses.
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Onchoi-Stenmark, Kim. "Fysisk aktivitet i klassrummet- RunRabbit." Thesis, Umeå universitet, Designhögskolan vid Umeå universitet, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-137764.

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Vi vet att fysisk aktivitet är någonting som är bra för våran hälsa både fysiskt och psykiskt. Detta är någonting som många studier bekräftar. Detta arbete handlar om att hitta ett koncept som hjälper läraren att ha fysisk aktivitet i det teoretiska klassrummet när det är lektion eller när klassen behöver ta en liten paus från lektionen. Konceptet är baserat på Motion Control Gaming och är en vision på hur ett det skulle funka, både som system, interface och produkt.
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Di, Matteo Clara. "Metodi numerici senza derivate per problemi di ottimizzazione black-box con variabili miste intere." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/20850/.

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In questa tesi si è voluto approfondire la risoluzione numerica di una particolare classe di problemi di ottimizzazione i cosiddetti problemi “black-box” con variabili miste intere. Il nome “black-box” deriva dal fatto che la funzione obiettivo agisce come una scatola nera, è possibile cioè studiarne il comportamento analizzando gli input e gli output, senza conoscerne il suo funzionamento interno. Spesso queste difficoltà derivano dal fatto che questi problemi sono ottenuti da procedure numeriche o mediante misurazioni sperimentali. Questi sono spesso caratterizzati dalla mancata conoscenza delle derivate della funzione obiettivo e dall'elevato costo computazionale della sua valutazione di funzione. Questo tipo di problemi sono molto frequenti nelle applicazioni. In questa tesi abbiamo analizzato numericamente il problema LEED (Low Energy Electron Diffraction) un vero e proprio problema “black-box” derivante dallo studio della struttura superficiale in scala atomica. Data la frequenza di questi tipi di problemi è stata sviluppata una classe di metodi numerici, detta “derivate-free”, ossia che non fa uso delle derivate della funzione obiettivo. I vantaggi di questi metodi sono l'affidabilità, la semplicità e la loro flessibilità: funzionano bene nella pratica e sono facili da implementare, inoltre hanno bisogno di pochi parametri. Tra i metodi derivative free abbiamo analizzato tre algoritmi noti in letteratura: BFO, DFL e NOMAD. Questi tre metodi cercano di trovare le soluzioni di minimo locale del problema partendo da un dato punto iniziale e andando a sondare i punti vicini seguendo delle direzioni che li caratterizzano. Del BFO è stata introdotta una nuova versione BFO-Relax che sfrutta la strategia di rilassamento delle variabili. Tutti i metodi sono stati analizzati sia dal punto di vista algoritmico che numerico su un'ampia classe di problemi test e sul problema reale LEED.
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Bally, Julia. "Synthèse et repliement des protéines dans les chloroplastes : effets collatéraux de l'expression massive d'un transgène." Thesis, Lille University of Science and Technology, 2008. https://ori-nuxeo.univ-lille1.fr/nuxeo/site/esupversions/112079bf-330d-489a-bfba-85ebc0c2c48c.

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Plastid genome engineering is an emerging technology which is being considered for the improvement of plant agronomic traits as well as for the molecular farming of biomaterials and therapeutic proteins. In the first part of this work, the potential of these organelles of prokaryotic origin to correctly fold and accumulate a disulfide bond containing enzyme has been investigated. Unlike a normal bacterial cytosol, the stroma of tobacco chloroplasts was found to support the formation of a recombinant alkaline phosphatase from Escherichia coli, whose activity and stability depend on the presence of two intra-molecular disulfide bonds. Targeting this enzyme to the thylakoid lumen via the Sec pathway resulted in stronger accumulation levels and higher specific activity. Complementary approaches have been initiated in tobacco using bacterial chaperones involved in the catalysis of disulfide bond formation, and a redox sensitive green fluorescent protein. These findings shed some light on the folding properties within chloroplasts, and have important biotechnological implications for the production in plants of many therapeutic proteins. Recombinant chloroplasts have the capacity to accumulate massive amounts of recombinant protein. The second part of this work focused on the consequences on the plant fitness and physiology of such extreme expression levels. We have analyzed tobacco plastid transformants accumulating alkaline phosphatase, a green fluorescent protein, and a bacterial hydroxyphenyl pyruvate dioxygenase. These lines exhibited a normal wild-type growth rate, and no significant perturbation of the chloroplast transcriptome was observed. In contrast, a proteomic approach on leaves revealed some differences, in particular a massive drop in the amount of Rubisco. The impact of recombinant protein expression on plant metabolism is discussed.
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Bally, Julia. "Synthèse et repliement des protéines dans les chloroplastes : effets collatéraux de l'expression massive d'un transgène : Protein synthesis and folding in chloroplasts : collateral effects of transgene massive expression." Thesis, Universite Des Sciences Et Technologies De Lille - Lille I, 2008. https://ori-nuxeo.univ-lille1.fr/nuxeo/site/esupversions/112079bf-330d-489a-bfba-85ebc0c2c48c.

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Du, Nan [Verfasser], Oliver [Akademischer Betreuer] Schmidt, Oliver [Gutachter] Schmidt, Christian [Gutachter] Mayr, and Heidemarie [Gutachter] Schmidt. "Beyond "More than Moore": Novel applications of BiFeO3 (BFO)-based nonvolatile resistive switches / Nan Du ; Gutachter: Oliver Schmidt, Christian Mayr, Heidemarie Schmidt ; Betreuer: Oliver Schmidt." Chemnitz : Universitätsbibliothek Chemnitz, 2016. http://d-nb.info/1213815185/34.

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38

Atkinson-Sheppard, Sally. "The Gangs of Bangladesh : exploring organised crime, street gangs and exploited child workers in Dhaka." Thesis, King's College London (University of London), 2015. http://kclpure.kcl.ac.uk/portal/en/theses/the-gangs-of-bangladesh(3ba577aa-cb23-412b-bf4a-19daeeadf873).html.

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This thesis presents a study of street children’s involvement as workers in Bangladeshi organised crime groups, based on a three-year ethnographic study in Dhaka. The study focuses on the views and experiences of 22 children from the streets and slums. Drawing on participant observation and group interviews with the children, the study explores how these children perceived organised crime and why young people become involved in these groups. It argues that children’s perspectives are essential, even when the subject under discussion is the adult world of organised crime. The study also utilises data drawn from interviews with 80 criminal justice practitioners, NGO workers and community members and three years of participant observation of the Bangladesh criminal justice system and wider society. This thesis offers five main contributions to knowledge. Firstly, the study documents the ways that Bangladeshi organised crime groups – the mastaans – operate. It explores how these groups are structured, the crimes they commit and their subculture. Secondly, the study demonstrates that mastaans are ‘mafia-type’ organisations that operate in a market for social protection and are involved in a range of criminal activities. Thirdly, the study explains how street children work as labourers within these crime groups. They are hired to carry weapons, sell drugs, collect extortion money, participate in ‘land grabbing’, conduct contract killings and commit political violence. It argues that mastaan groups offer street children a way to earn money and access patronage, protection and inclusion. The study concludes that these children are neither victims nor offenders; they are instead ‘active social agents’, doing what they can to protect themselves and survive on the streets. Finally, the study contributes to literature on research methodologies, because it was the first to employ an empirical case study design to explore the relationship between street children and organised crime in Bangladesh.
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Pooley, Oliver James. "Electron transport in InSb/AlInSb semiconductor heterostructures." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/electron-transport-in-insbalinsb-semiconductor-heterostructures(42798359-2505-4a29-bfea-a32283c84fc6).html.

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InSb has the lowest bulk electron effective mass and the narrowest band gap of the III-V semiconductors, as well as a large dielectric constant and Lande g-factor, as a result of strong spin orbit coupling. These properties make it an exciting candidate for many different applications including high speed electronics and spintronics.This thesis presents a series of investigations on InSb/AlInSb quantum well (QW) heterostructures. The nature of transport through samples is characterised using magneto-transport measurements including Hall measurement, quantum Hall measurement, and Shubnikov de Haas oscillations. The QW 2 dimensional electron gas (2DEG) carrier densities and mobilities are extracted along with carrier densities and mobilities for transport parallel to the 2DEG. The mobilities are explained in terms of the various scattering mechanisms postulated to be present. The importance of thermally generated carriers in the lower AlInSb barrier material and the role of screening by carriers within the delta-doping plane are considered. A surface gate incorporating a gate dielectric is shown to significantly modify the transport properties and results in an increased mobility over ungated structures with the same carrier density.The measurement and analysis of transport into a 2DEG (Schottky barrier) is also presented and this transport modelled in the thermionic emission regime (by incorporation of an ideality factor) and the tunnelling regime. Gate electrodes are then used to confine the electrons in the 2DEG further to 1D. Conductance measurements are presented on split gates, demonstrating well formed conductance quantisation steps. The sensitivity of the steps presented suggest that split gates on InSb/AlInSb heterostructures could make suitable charge detectors in an electron spin qubit, an application which pushes InSb into being a practical candidate for quantum information devices.
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Senate, University of Arizona Faculty. "Faculty Senate Minutes February 6, 2012." University of Arizona Faculty Senate (Tucson, AZ), 2012. http://hdl.handle.net/10150/215449.

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41

Al-Shaghdari, Mohammed A. "The evaluation of time-dependent flow in swirl burners." Thesis, University of South Wales, 1997. https://pure.southwales.ac.uk/en/studentthesis/the-evaluation-of-timedependent-flow-in-swirl-burners(e2caff50-bfda-4bc9-85f4-e91182d53bd7).html.

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Swirl burners are widely used in industry. Recent environmental concerns, particularly on emissions from combustion processes, have introduced the requirement to modify these processes to reduce emissions whilst at the same time maintaining combustion efficiency. This thesis presents details of experimental and computational studies into the flowfield structures of swirl burners. Previous investigators have concentrated on the time-average flows, but it has become apparent that these are insufficient to enable pollutant emissions to be accurately predicted. Knowledge of the time-temperature and species history is needed to obtain better predictions. Pivotal to this is a detailed determination of the time-dependent structure of the flow. In this study, series of experiments were carried out at different inlet configurations and conditions. The flowrate and swirl number were varied as well as the injection mode, inlet length and exit geometry. The burner flow was characterised by measuring axial, tangential and radial velocities using a Laser Doppler Anemometer. A Computational Fluid Dynamics modelling package, FLUENT was used to produce two and three-dimensional computational models to predict the flowfield structures of the burners in isothermal and combustion cases. Four turbulence models were evaluated in the prediction: the k-e Model, the Algebraic Stress Model (ASM), the Reynolds Stress Model (RSM) and the Re-normalisation Group Model (RNG). Constant velocity scaling of the 100 and 500 kW burner was examined in both experimental and computational studies. The experimental results show that the flowfield structures in both burners are nonaxisymmetric and develop three-dimensional time-dependent coherent structures in the flow. The experimental results have been compared with the computational model predictions. The comparisons reveal very good agreement between the time average measurement and the predictive values, especially downstream of the burner exit. This work was extended to investigate the following novel phenomena: a). The computational prediction of the flowfield structure was extended to include different inlet boundary conditions with both the RSM and the RNG turbulence models. The model was also extended to investigate the time-dependent flows. b). The influence of varying the inlet and exit geometries and conditions on the flow patterns and the reverse flow zone was examined in detail. A 500 kW swirl burner with scroll inlet was designed and characterized with time-dependent flows to simulate the Precessing Vortex Core. This investigation showed very good agreement with experimental velocity data with less constrained boundary conditions that had previously obtained. The time-dependent simulation was limited by the computer speed and processing capability but identified that such analysis is possible when computer power allows and has the potential to model the flow in greater detail yielding more accurate data on pollution emissions.
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Sarsfield, Donal Robert. "Portfolio of original compositions and analytical commentary." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/portfolio-of-original-compositions-and-analytical-commentary(805142f6-b06e-499f-bfaa-371362235972).html.

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This portfolio of original compositions investigates how a concentrated perspective on one particular sound source has the potential to develop a perceptual link between the listener, the work and the world in which we live. To this end a contradictory approach to organising sound is employed; sounds are chosen for their intrinsic properties but are never fully removed from their referential identity. This approach is framed within a broad awareness of cultural listening, which recognises the value of the sound sources in society, but within the confines of the work these sounds operate with neutral symbolic function in order to emphasise their morphological identity. The commentary discusses the main issues arising relating to the composition of the six works in the portfolio, namely the recording, transformation and organising of recorded sound.
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43

Holmsten, Jenny. "Future Forests - Vision 2030 : Bachelor Thesis Report - Jenny Holmsten." Thesis, Umeå universitet, Designhögskolan vid Umeå universitet, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-106634.

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Forests cover about 30% of the earth surface and is a vital resource as a habitat for plants, animals and humans. Today climate change and global warming is a fact and something must be done. We burn massive amounts of fossil fuels and during this combustion carbon dioxide is created. To help eliminate this global change we need to start caring about the forests. The forests have a major role in climate change and global warming. It currently contributes to about one-sixth of the global carbon emissions. But today deforestation is a real environmental threat. The world trees are being cut down too quickly for the earth to regenerate new forests. And while the society is moving into a more bio-based economy the pressure of a efficient forest industry and forest regrowth is increasing drastically. A new way of reforestation must happen, a sustainable and natural method must be im plemented. In Sweden and the Scandinavian area the method has had a stagnant development. Is done manually with a standardized procedure not taking natural properties into account. Money often goes over quality. My project will focus on developing a concept that can live up to the upcoming future demands and the environmental aspects that needs to be taken in account to ensure a healthy and sustainable forest. The final result performs an efficient and precise reforestation and enables for a detailed planning and analysis of the area in advanced.
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Yuan, Shuai. "Essays in auditor regulation : evidence from the EU." Thesis, King's College London (University of London), 2018. https://kclpure.kcl.ac.uk/portal/en/theses/essays-in-auditor-regulation-evidence-from-the-eu(62e11867-bfca-4964-b97c-06e133159217).html.

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With the publication of Directive 2006/43/EC, a system of public oversight over the audit profession was implemented across the European Union. This thesis analyses the resulting costs and benefits of national external audit monitoring systems, and evaluates the efficiency and effectiveness of public oversight practices in Europe. First, it reviews the development of audit regulation in Europe, both before and after the release of Directive 2006/43/EC. It then reviews previous studies on the effects of regulation and cost-benefit analyses. Besides, it reviews studies specifically on public oversight systems, mainly in the United States (US), with a small number outside the US. The literature suggests there is mixed evidence for the efficiency and effectiveness of the public oversight system in the US, and further research is needed on public oversight systems, particularly in institutional settings outside the US. The two empirical chapters explore the audit pricing and quality consequences of the inspection regime, at pan-European and UK levels. Both studies find an increase in audit prices but no apparent impact on audit quality associated with audit inspection practice. This thesis contributes to the literature on audit regulation and has implications for policy making by auditing regulators.
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Wague, Baba. "Matériaux sans plomb micro structurés pour la récupération d'énergie." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEC003/document.

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Avec le développement des circuits intégrés à très faible consommation d'énergie, la nécessité de réduire les coûts d'exploitation des dispositifs électroniques embarqués et l'utilisation des piles usagées constituant une menace pour l'environnement, le concept de récupération d'énergie a acquis un nouvel intérêt. La récupération d'énergie couvre le piégeage de nombreuses sources d'énergie ambiantes perdues et leur conversion en énergie électrique. Une large gamme de dispositifs de récupération d'énergie des vibrations mécaniques a été développée. Une configuration commune consiste en un système de masse-ressort avec un matériau piézoélectrique en parallèle avec le ressort pour convertir une partie de l'énergie mécanique pendant les oscillations en énergie électrique. Jusqu'à présent, le matériau le plus utilisé pour la récupération d'énergie piézoélectrique est le titano-zirconate de plomb (PbZr1-xTixO3) (PZT). Le PZT est le matériau de référence pour les applications microsystème électromécanique-MEMS (MechanoElectroMechanicalSystems) dans le domaine de la récupération d'énergie. Les matériaux piézoélectriques à base de plomb tels que le PZT et niobate-titanate de plomb-magnésium (PMN-PT) offrent des facteurs de couplage piézoélectriques supérieurs à ceux d'autres matériaux. Cependant, malgré ses excellentes propriétés électriques (diélectriques, ferroélectriques et piézoélectriques), le PZT et d'autres matériaux à base de plomb devraient bientôt être remplacés par des composés sans plomb, à cause des problèmes environnementaux. Notre travail vise à développer des matériaux sans plomb de haute performance pour la récupération d'énergie par vibration mécanique. Nous nous sommes intéressés à la fabrication et la caractérisation des dispositifs MEMS pour la récupération d'énergie en utilisant les matériaux piézoélectriques sans plomb tels que le nitrure d'aluminium (AIN), le titanate de baryum BaTiO3 (BTO) et la ferrite de bismuth BiFeO3 (BFO). Les matériaux piézoélectriques PZT (utilisé comme référence à cause ses coefficients piézoélectriques élevés), BTO, BFO et AIN ont été déposés en utilisant des méthodes de dépôt telles que la pulvérisation cathodique et le dépôt sol-gel, conduisant à des films minces à grande échelle, homogènes et de haute densité, avec une épaisseur contrôlée avec précision. Le dépôt de films de 300 nm d'épaisseur par pulvérisation cathodique ou par Sol-Gel a été réalisé sur du substrat de SrTiO3 (STO) recouvert d'une électrode inférieure de SrRuO3 (SRO), qui est le substrat de référence pour les oxydes fonctionnels (PZT, BTO et BFO), et sur un substrat de silicium recouvert de platine, qui est le modèle industriel classique. Quels que soient les matériaux piézoélectriques, nous avons obtenu des films épitaxiés sur substrat de STO et texturés sur substrat de silicium. Des mesures structurales, électriques et piézoélectriques sur les films de BTO, AIN et PZT montrent qu'ils ont de bonnes propriétés physiques en accord avec la littérature
With the development of ultra-low-power integrated circuits, the need to reduce operating costs for embedded electronic devices, and since used batteries pose a threat to the environment, the concept of energy harvesting has gained a new relevance. Energy harvesting covers the scavenging of many lost ambient energy sources and their conversion into electrical energy. A broad range of energy harvesting devices has been developed to scavenge energy from mechanical vibrations. A common configuration consists of a spring-mass system with a piezoelectric material in parallel with the spring to convert some of the mechanical energy during oscillations into electrical power. So far the most used material for piezoelectric energy harvesting is the Lead Zirconate Titanate (PbZr1-xTixO3) (PZT). PZT is the reference material for MEMS (MechanoElectroMechanicalSystems) applications in the field of energy harvesting. Lead-based piezoelectric materials such as PZT and lead magnesium niobate-lead titanate (PMN-PT) offer incomparable piezoelectric coupling factors to other materials. However, despite its excellent electrical properties (dielectric, ferroelectric and piezoelectric), PZT and other Lead based materials should be replaced shortly by leadfree compounds, due to environmental issues. Our work aims at developing lead-free high performance vibration energy-harvesting. We focus on the fabrication and characterization of aluminum nitride (AlN), Barium titanate BaTiO3 (BTO) and Bismuth ferrite BiFeO3 (BFO) devices for energy harvesting. PZT (as a reference because it’s high piezoelectric coefficients), BTO, BFO and AlN have been deposited using sputtering methods, leading to high homogeneous, large scale thin films with a precisely controlled thickness. The deposition of 300nm-thick films by sputtering or spin coating was performed on SrTiO3 (STO) substrate with SrRuO3 (SRO) bottom electrode, which is the reference substrate for the functional oxides (PZT, BTO and BFO), and platinum coated silicon substrate, which is the classic industrial template. Whatever the piezoelectric materials, we obtained epitaxial films on STO substrate and textured films on silicon substrate. Structural, electrical and piezoelectric measurements on the BTO, AlN and PZT films show that they have good physical properties in agreement with the literature
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Cook, Elizabeth. "Bereaved family activism in the aftermath of lethal violence." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/bereaved-family-activism-in-the-aftermath-of-lethal-violence(2a1689e2-c5e5-4aa4-bfca-60a495c11cfd).html.

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The boundaries of victimhood have received increasing attention in criminology, particularly considering the recent proliferation in 'trauma talk' or 'trauma creep'. Noting the connections between victims and trauma, there is now increasing recognition of the impact of victimisation, not only on individuals, but upon families, communities and cultures with its effects extending across time, place and person. Following David Garland's assertion of the 'return of the victim' 15 years ago, the interests of victims have moved to centre stage of the criminal justice system with the experiences of some taken to be representative of others. While this has encouraged an appreciation of the extent of suffering in victimisation, it is easy to understand how we might 'lose sight of the individual victim'. This research presents a qualitative study of the phenomenon of bereaved family activism. Findings presented in this thesis are based upon 15 in-depth interviews and participant observations with Mothers Against Violence: a Manchester-based charity that emerged in response to an intense period of gun violence and ensuing community outcry in the 1990s. The aim of this thesis was to explore how victims have confronted and mobilised their experiences of lethal violence to promote acknowledgment and prompt recognition. By refocusing on the individual and foregrounding the victim, this thesis asked how those involved understand, make sense of and give value to their experience in light of their role in Mothers Against Violence. Data collected was analysed through thematic analysis, remembering the embedded nature of such stories in cultural, historical and biographical contexts, communities and the research exchange. Findings are presented as a way of following the stories of individuals to the moment of collective action. The primary contributions of this thesis can be summarised under the following headings; firstly, applications of 'trauma' in victimology; secondly, understanding victim movements such as Mothers Against Violence as spaces for emotional, social and practical learning; thirdly, conceptualising victimisation as one moment in a series of 'turning points'; and fourthly, the role of stories in prompting recognition, encouraging identification and assembling communities.
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Capes, Renalt Edward. "The development of satellite radar interferometry for geohazard application." Thesis, University of Portsmouth, 2017. https://researchportal.port.ac.uk/portal/en/theses/the-development-of-satellite-radar-interferometry-for-geohazard-application(304e4685-39e5-4d0f-bfca-c37b2194ebaf).html.

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This thesis for a PhD by Publication attempts to demonstrate the author’s contribution towards the development of terrestrial satellite radar interferometry (InSAR) for geohazard applications between 1995 and 2016. The author’s role is shown by reference to six peer-reviewed articles, and five ‘documents of influence’ that demonstrate key pieces of work that helped progress the application of InSAR technology. The work included ranged from the first InSAR-related contract to be funded by ESA, through the introduction of InSAR into the CEO’s Disaster Management Support project that influenced both the Space Charter for Major Disasters and the Global Monitoring for Environment and Security programme, to the widespread exploitation and standardisation of InSAR seen in the Terrafirma and FP7 PanGeo projects. The author’s contributions have resulted in a wider-spread InSAR awareness and expertise, direct support to the European Space Agency’s flagship application of the time, the inclusion of InSAR within Copernicus services, and support to the mission-design of Sentinel-1a/b.
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48

Larsson, Caroline. "Topi - How can we ease allergy vaccination for children in the age of 5-12?" Thesis, Umeå universitet, Designhögskolan vid Umeå universitet, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-135760.

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30% of children and youths in Sweden have some form of allergy disease and for many people medicines are not sufficient. If so, there is a possibility of an allergy vaccination, a three to five-year process where the patients receive 50-80 injections. So what is the main problem? In fact, it is important to understand that the vaccination is something that affects the child in greater extent than just the moment when the syringe is provided. At present, the patient must stay to ensure that he/she does not get an allergic reaction and is feeling well enough to go home. They are constantly questioned about how they feel. But how does a child determine this? How good is good enough? Topi is a system that increases the involvement and transfer responsibilities from the child by keeping track of their well-being and surroundings - while making treatments more fun and safe. The project is funded by Swedish Asthma and Allergy Association´s Research Foundation
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Wei, Jianfei. "Effect of hydrogen on the corrosion performance of zirconium alloys." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/abstracteffect-of-hydrogen-on-the-corrosion-performance-of-zirconium-alloys(b6683f8b-9286-4ebd-bf8a-d240c62b7a79).html.

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This study is part of the multidisciplinary research program funded by the EPSRC aimed at further understanding the mechanisms behind the oxidation, transition and breakaway of zirconium alloys. The current study concentrates on the effect of artificially introduced hydride rich rim region upon the corrosion performance of zirconium alloys. The methodology of cathodic hydrogen charging of zirconium specimen has been described. The intention is to create a hydride rich rim similar to observation made in end-of-life fuel claddings from nuclear reactor. The overall hydrogen levels in the samples were determined via inert gas fusion and the local hydride volume fractions via laboratory x-ray diffraction. The residual stress state in the rim was investigated by synchrotron x-ray diffraction. The rim was determined to have local hydrogen levels about 11,000 wt.ppm and predominantly δ-hydrides. Hydrided samples and their references were tested in autoclaves simulating primary water environment. Reference samples exhibited typical corrosion kinetics with a change from pre- to post-1st transition. The duration before 1st transition varies with alloy chemistry and heat treatment conditions. Hydrided samples generally experienced accelerated corrosion while the extent to which the material was affected depends on alloy chemistry. Parabolic rather than cubic oxide growth with a very slow early corrosion rate was recorded in hydrided alloys. Both hydrided and reference samples of three Zr-Sn-Nb alloys, ZIRLOTM, low tin ZIRLO and X2 with tin concentration ranging from 0.14 to 0.92 wt.% became the gravity of further characterisations since they exhibited improved corrosion performance with decreasing tin content. The microstructure of the oxide was investigated via cross-sectional Scanning Electron Microscope (SEM). The residual stress state in tetragonal and monoclinic phases as well as tetragonal phase fraction were studied via synchrotron x-ray diffraction, showing high in-plane compressive stresses in the oxide of different levels depending on the phase and alloy. The presence of a hydride rim lowered the residual stress. White oxide in hydrided samples displays lower residual stress level, smaller tetragonal phase fraction and higher degree of oxide grain misorientation when compared to black oxide regions of reference and hydrided samples. It was also found that the hydride rim region undergoes local depletion of hydrides in alloy with low Sn content during the early stage of aqueous corrosion. Finally a model was given to describe the different roles played by individual oxide and hydride phases during the oxidation of zirconium alloys.
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Smith, Paul. "Exploring the role of technology acceptance in business buying of tax technology." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/exploring-the-role-of-technology-acceptance-in-business-buying-of-tax-technology(7dd62167-266f-4372-bf8a-c189fb235fd6).html.

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This study developed and empirically examined a model to help understand how key individuals in businesses decide on whether or not to buy and utilise technology in the context of managing their obligations in relation to business taxes. In restricting the frame of reference to a taxation context, it enabled a link to be made to individual decision making, as it is ordinarily the case that one lead buyer is evident in the context of tax and technology in organisations. The model was developed from a review of extant literature in the areas of technology acceptance, behavioural intention, and consumer and business buying models. The overall model was built on a framework that has at its core the Augmented Technology Acceptance Model (Taylor & Todd, 1995a). A correspondence between attitude to use of the technology and product quality is theorised, allowing a connection to a wider model of purchase intention. The initial model was developed with thirteen hypotheses, ultimately leading to an examination of intention to buy tax technology. After an initial pilot study, in the main study a questionnaire was designed to capture empirical data for measurements related to the model. Data collected from 125 informants (i.e. senior tax staff in large organisations) about tax technology buying decisions they were currently considering was used to empirically test the model, using Structural Equation Modelling. The low sample size caused a need to simplify the original model to retain statistical power. This had the result of reducing the number of hypotheses to ten. The analysis was performed testing the measurement model and the model fit and thereby investigating its underlying hypotheses. The results supported the key hypotheses and the overall explanatory power of the model in examining intention to buy tax technology was strong. The use of technology acceptance principles as core to helping explain buying intention for tax technology was strongly supported. Only one hypothesis was not supported, relating to a proposed positive relationship between Relationship Quality and Intention to Buy constructs. Potential explanations for this finding with regard to relationship quality were introduced. The general research contributions and implications of the study were also discussed.
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