Tesi sul tema "Preservation"
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1
Attia, Magdy. "Improved preservation techniques for organ preservation". Thesis, University of Leeds, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.396549.
Testo completo
2
Branan, Kenyon Garrett. "Relationship preservation". Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/120671.
Testo completoAbstract (sommario):
Thesis: Ph. D. in Linguistics, Massachusetts Institute of Technology, Department of Linguistics and Philosophy, 2018.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 329-351).
This thesis deals with a number of puzzles related to word order, in which the co-occurence of two elements in the same clause imposes a restriction on the distribution of these elements. I suggest that elements involved in Agree relationships [Chomsky (2000, 2001)] are subject to a requirement that they be aligned with the left or right edge of a prosodic phrase, following work done in Richards (2016). I argue that there is a restriction on the opaque satisfaction of this requirement, and show that this provides a unified solution to these word order puzzles. Chapters 1 and 2 deal with movement phenomena, primarily in left-headed languages. In chapter 1, I show that some languages allow A-movement of subjects across other DPs, whereas others do not. I note that this appears to be determined by which edge of a prosodic phrase they require phrases in Agree relationships to be aligned with, and show that this is a consequence of the proposed restriction on opaque satisfaction of the alignment requirement. Chapter 2 builds on the results of chapter 1. I show that A-movement of a subject may cross another nominal in all languages, but only if there is a phase boundary between the launch site and landing site, and show how this falls out from the proposed restriction on opacity. I show also that languages that do not allow A-movement of subjects across other DPs display a similar restriction in wh-questions, and argue that this too is a result of the proposed restriction on opacity. Chapters 3 and 4 deal with the distribution of wh-phrases in languages that allow them to remain in-situ. Chapter 3 deals with co-occurance restrictions between foci and wh-phrases. I argue that these restrictions emerge as a result of a conflict between a prosodic strategy that languages might use to satisfy the alignment requirement, called Grouping, and the proposed restriction on opaque satisfaction of this requirement. Chapter 4 deals with Grouping more generally. I show that languages with Grouping have a particular prosodic signature which marks phonological phrases that contain wh-phrases, whereas languages that lack Grouping do not, and explore the consequences of this for the architecture developed in this thesis.
by Kenyon Garrett Branan.
Ph. D. in Linguistics
3
Monzel, Daniel Robert. "Fabricated Preservation". Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/98492.
Testo completoAbstract (sommario):
"Fabricated Preservation" aims to push the boundaries with traditional theses, creating a multi-layered experience that blends fact and fiction through a performance that centers around environmental storytelling in virtual reality. The experience questions the balance of theatrical elements in traditional storytelling which forefront text and human characters over architecture, props, and environment, and critically examines how an environment can play a crucial role in a narrative. The narrative itself focuses on one question: if a genealogy company had access to past environments via time travel, what new information could we learn about our ancestors?
The normal perceptions of a "game" are challenged, introducing real world elements to trick the audience and subtly influence how they navigate a virtual space. A complex fictional character is introduced through the performance and developed through the environment, with the hopes that the audience will gain some emotion toward them: either connecting with the character as if they were a close friend, or feeling unsettled that they observed the character's realistic personal space. This voyeuristic theme weaves its way through each layer of the storytelling, poking at the audience's morals with the hopes that they will question the experience around them.
Above all, the main goal of Fabricated Preservation is to challenge the audience to mentally engage with the virtual experience, by paying attention to the details of their environment and constructing their own version of a narrative from those details.Master of Fine Arts
Fabricated Preservation examines how an environment can play a crucial role in a narrative. An environmental story was created that centers around a fictional character, influenced by a close friend's life. Virtual reality was used to allow the audience to immerse themselves more within a virtual bedroom environment, using virtual props to convey the personality of the character. A fictional genealogy company called The Fifth Turning was also created to convey that environmental story through a different perspective to the audience. There are two main stories that go hand in hand with this experience: the primary story is the life of a college girl in the 1990s. The secondary story is of the fictional company, the Fifth Turning, which uses time travel technology to access the bedroom environment of the college girl to obtain more personalized genealogy information.
4
Brohman, Stephanie Anne. "(Self) Preservation". Thesis, University of Iowa, 2016. https://ir.uiowa.edu/etd/3053.
Testo completoAbstract (sommario):
Creatures of the sea, creating wearable adornment to protect the body and unique materials, inspire my artwork. Through research and examination of sea creatures, I look to their defense mechanisms and imagine what it would be like if humans had similar qualities or if we could borrow from these beings and transform the way we physically protect our bodies. Through mixed materials I form adornment that acts as armor and the human being and the sea creature merge. The following pages will give you access to my thought process, accounts of technical experimentation, and my body of work.
5
Hart, Nils Arnaud 't. "Improving liver preservation new strategies in liver procurement and preservation /". [S.l. : Groningen : s.n. ; University Library Groningen] [Host], 2007. http://irs.ub.rug.nl/ppn/30406856X.
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6
Tharian, Suzanna. "Tourism and preservation". Kansas State University, 1996. http://hdl.handle.net/2097/36074.
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7
Carvalho, Beatriz Trinchão Andrade de. "Image-based appearance preservation". reponame:Repositório Institucional da UFPR, 2013. http://hdl.handle.net/1884/34698.
Testo completoAbstract (sommario):
Orientadora : Profª Drª Olga Regina Pereira BellonCoorientador : Prof.Dr. Luciano Silva
Tese (doutorado) - Universidade Federal do Paraná, Setor de Ciencias Exatas, Programa de Pós-Graduação em Informática. Defesa: Curitiba, 11/10/2013
Inclui bibliografia
Resumo: A preservação tridimensional digital de objetos reais compreende dois aspectos: a preservação da forma do objeto e a preservação de sua aparência. Esta tese tem como foco a preservação da aparência de objetos reais baseada em imagens e provê uma série de contribuições sobre o tema. A primeira contribuição consiste em dois grupos de experimentos, onde cada um trabalha uma abordagem diferente na preservação da aparência baseada em imagens. Esses experimentos são baseados em conceitos fundamentais relacionados ao comportamento da luz e em uma compilação de trabalhos que visam preservar a aparência de objetos reais usando diferentes tipos de imagens. O primeiro grupo de experimentos tenta desconsiderar ao máximo a inuência da luz. O segundo vai um passo além e considera uma única fonte de luz. Estes experimentos são a base e motivação para o desenvolvimento da principal contribuição desta tese, que é um novo método de preservação da aparência baseado em imagens que considera todo o ambiente como fonte de luz. Ele apresenta como novidade o fato de estimar a luz vinda de todo o ambiente para cada ponto em uma região na superfície de um objeto. Até onde foi pesquisado neste trabalho, nenhum método existente adota essa abordagem. Considerar todo o ambiente como fonte de luz permite configurações flexíveis durante a aquisição e, já que reproduz o que acontece na realidade, recupera informações potencialmente mais confiáveis sobre a iluminação incidente. Esta tese apresenta este método e sua aplicação em ambientes reais e sintéticos. Conclusões sobre este trabalho são apresentadas e direções.
Abstract: The three-dimensional digital preservation of real objects comprises two main aspects: the preservation of the shape of the object and the preservation of its appearance. This thesis focuses on the image-based appearance preservation of real objects and provides a set of contributions on the theme. The first contribution consists in two groups of experiments, where each one of them targets one different image-based appearance preservation approach. These experiments are based in fundamental concepts related to the behavior of light and in a compilation of works that aim to preserve the appearance of real objects using different types of images. The first group of experiments attempts to disregard as much as possible the inuence of the environment light. The second one goes one step further and considers a single light source. These experiments were the basis and motivation for the development of the main contribution of this thesis, which is a novel image-based appearance preservation method that considers the whole environment as a source of light. It presents as novelty the fact that it estimates the incoming light from the whole environment to each point in an object surface patch. At the best knowledge of this work, none of the current existing methods adopts this approach. Considering the whole environment as source of light allows exible acquisition setups and, as it reproduces what happens in reality, potentially retrieves more reliable information about the incident lighting. This thesis presents this method and its application on real and synthetic environments. Conclusions about this work are presented and future research directions are discussed.
8
Jamieson, N. V. "Liver preservation for transplantation". Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.605054.
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9
York, Audrey K. "Indiana farm structure preservation". Virtual Press, 2005. http://liblink.bsu.edu/uhtbin/catkey/1314227.
Testo completoAbstract (sommario):
Agriculture has played and continues to play a vital role in the livelihood of Indiana; therefore, farm structures are present in nearly every section of the state. However, with advances in technology and commercial and residential development, historic farm structures are quickly being lost to demolition and neglect. Although Indiana is known as a leader in historic preservation, historic farm structures of the state do not receive the attention that they deserve from preservationists. This thesis serves to inform preservationists of the importance of Indiana's historic farm structures and to present suggestions on ways that the current programs and activities could be improved. This is accomplished by discussing the history and current state of farming in Indiana, by examining farm structure preservation organizations in Indiana and across the nation, and by presenting farmland preservation and the documentation of rural historic districts as two alternative tools to protect historic farm structures.Department of Architecture
10
Witt, Sarah (Sarah Elizabeth). "Preservation of a species". Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/68417.
Testo completoAbstract (sommario):
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, September 2011."September 2011." Cataloged from PDF version of thesis.
Includes bibliographical references (p. 141-142).
To put it simply, humans are going extinct. I identify the source of the problem as an imperceptible societal trend to eliminate the experience that authenticates us as a living species: failure. We've unanimously designated its unattainable opposite as the standard of success: perfection. This quality is a requisite of our accelerated culture, the achievement manifested in an exponentially growing inventory of artifacts that are "faster, sleeker, better." And humans are becoming some of them. In the search for ever-increasing modes of efficiency and precision, humans have adapted their posture to the rigidity of architecture and adopted proliferate technological mediators as prosthetics. The overwhelming pressure to occupy a flawless state of being is a symptom of society, generated by the ego and aggravated by our continual exposure to environments that boast aesthetic and functional attributes exceeding our own. In a competitive fashion, we've subjected ourselves to a mechanical and agitated lifestyle that demands instantaneous reaction, shaping us into receivers and transmitters that function at impeccable and unsustainable speeds. My artistic practice is a critical investigation of human behavior as it is informed and manipulated by the prescriptive streamlined circumstances we've constructed and similarly inhabit in our digitally saturated culture. Instinctual impulses and organic chaos are suppressed in the automatic and regulated state incited by our technoutopian environments. I use performance to explore three general interfaces that I've located as antagonistic towards natural human behavior: architecture, technology and codes of regulation. Primarily employing myself as a subject, I design situations in which I contend with the three aforementioned interfaces, and subsequently have developed a catalogue of responses that strive to mitigate the external forces governing human behavior.
by Sarah Witt.
S.M.
11
Poliachik, Sandra Louise. "Transplant organ preservation cooler". Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/41591.
Testo completoAbstract (sommario):
A method for preserving transplant organs for extended periods of time has been developed in the transplant organ preservation cooler. The preservation cooler enhances organ viability by maintaining a temperature controlled organ bath and pumping perfusate through the transplant organ.
The emphasis on the transplant organ preservation cooler is to provide a simple and portable system which will be powered by boiled off oxygen from a liquid oxygen source. The design of the preservation cooler pump and temperature control system are presented. Results of tests proving the successful operation of the preservation cooler prototype are also presented.Master of Science
12
Ying, Daniel B. "Divine preservation in salvation". Theological Research Exchange Network (TREN), 1999. http://www.tren.com.
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13
Henken, Helen Elizabeth. "Preservation of the faith". Online full text .pdf document, available to Fuller patrons only, 2003. http://www.tren.com.
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14
Efhamisisi, Davood. "Preservation of plywood against biological attack with low environmental impact using tannin-boron preservative". Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS235/document.
Testo completoAbstract (sommario):
Une étude expérimentale a été menée afin de protéger des attaques biologiques des contreplaqués faits d'essences non durables (hêtre et peuplier), et ce, avec un faible impact environnemental. Des produits de protection à base de tannins et de bore, nouvellement développés afin de réduire le lessivage du bore, ont été sélectionnés pour ce but. Ce système a été utilisé pour protéger les contreplaqués selon deux approches : (1) au niveau de la colle pour remplacer les adhésives à base de formaldéhyde et coller les plis, (2) en traitement des plis avec des formulations plus diluées, les plis étant collés avec des adhésifs mélamine-urée-formaldéhyde. Les données expérimentales de cette thèse peuvent être classées en trois grands groupes : essais chimiques et thermomécaniques des colles tannin-bore, mesure des propriétés physiques et mécaniques, de la résistance biologique avant et après vieillissement des différents panneaux. Les essais chimiques sur les colles tannin/hexamine ont montré que l'addition de bore sous forme d'acide borique peut contribuer à plus de liaisons inter-flavonoids et à ouvrir les cycles pyranes ce qui accélère les réactions de polymérisation. Des analyses thermomécaniques sur les colles contenant des tannins de mimosa et de quebracho ont confirmé que l'addition d'acide borique (1) abaissait le temps et la température de prise, et (2) augmentait les valeurs du module d'élasticité de la colle. L'addition d'une quantité optimale d'acide borique dans la colle à base de tannin augmente les propriétés physiques et la résistance au cisaillement. Une charge excessive d'acide borique (10%) dans la colle est la cause de pertes de propriétés mécaniques et physiques. Bien qu'en faible quantité, l'introduction de l'acide borique dans la colle de tannin amène une protection efficace contre l'attaque fongique, même après un lessivage selon l'EN 1250-2. Les résultats des essais termites montrent que l'acide borique contenu dans la colle cause le plus faible taux de survie des insectes et de perte de masse, mais présentent un fort degré d'attaque selon une cotation visuelle. Aucune amélioration n'a été obtenue lors d'un essai de choix après lessivage. Les contreplaqués faits de plis traités par des solutions tannin-bore ont montré des résistances au cisaillement plus faibles, mais toujours dans les gammes requises pour des applications en atmosphère humide. Des résultats satisfaisants ont été obtenus par les réseaux polymères de tannins, même après une lessivage sévère, vis-à-vis de l'attaque fongique. Les contreplaqués faits de plis traités à l'acide borique seul ont présenté une sensibilité importante à l'attaque biologique après un lessivage. Les résultats des essais termites ont montré un faible taux de survie des insectes et de perte de masse, même après un lessivage sévère, pour les contreplaqués avec des plis traités par des systèmes tannin-bore. Les résultats d'un essai de choix a montré que les termites préféraient se nourrir des témoins quand l'alternative proposée était des échantillons traités avec des systèmes tannin-boreAn experimental investigation was conducted to protect plywood panels made of perishable wood species (beech and poplar) against biological attacks with low environmental impact. The newly developed tannin-boron preservative which was proposed to reduce the leaching of borates was selected for this purpose. This system was used to protect plywood with two approaches: (1) in the glue line to replace formaldehyde based adhesives and gluing wood veneers, (2) pretreatment of wood veneers with the diluted formulations and bonded with melamine-urea-formaldehyde resin The research data in this thesis were obtained from three main groups of experiments: chemicals and thermomechanical testing on the tannin-boron resin, measuring physical and mechanical properties, and different biological tests before and after leaching processes. The chemicals testing on the tannin/hexamine adhesive showed that the addition ofboron, in the form of boric acid, can contribute more inter-flavonoid linkages and the opening of pyran rings which leads to the acceleration of polymerization reactions. Thermomechanical analysis on the adhesives of mimosa and quebracheo tannins confirmed that the addition of boric acid (1) lowered time and temperature of hardening, (2) and increased modulus of elasticity values of the adhesive. The addition of optimal boric acid into the tannin adhesive upgraded physical properties and tensile shear strength. An excess loading of boric acid (10%) in the glue line caused imperfect physical and mechanical features. Despite the low uptake of boric acid but its addition into the tannin glue provided effective resistance against fungal attack even after mild leaching test according to the EN 1250-2. The results of termites test showed that increase in the boric acid content of the adhesive caused the lower survival rate and the weight loss but samples underwent the high level of attack. No improvement against termite attack was obtained after leaching by a choice feeding test. The plywoods made of pretreated veneers by tannin-boron solutions showed partially lower tensile shear strength but still in the range of standards requirements for the humid applications. The satisfactory results were obtained even after severe leaching test against fungal attack with a strong polymeric network of tannin. The control plywoods made of pretreated veneers with boric acid alone solutions presented significant sensitivity against biological attack after leaching test. The results of termite tests showed the lower survival rate and the weight loss even after severe leaching test for the plywoods made of pretreated veneers with tannin-boron systems. The results of choice feeding test showed that termites preferred feeding from the controls when alternative samples were treated with the tannin-boron system. In general the evidence from this study suggests that tannin-boron system can significantly slow down the leaching of boron and it rendered high potential to preserve plywood
15
Quaresma, Patrícia Jorge Marques. "Chocolate milk preservation by hyperbaric storage, a new and environmentally friendlier preservation technology". Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/21246.
Testo completoAbstract (sommario):
Mestrado em BiotecnologiaO principal objetivo deste trabalho centrou-se no estudodo efeito do armazenamento hiperbárico (AH) à temperatura ambiente, em leite achocolatado, de modo a evitar a sua deterioração a nível microbiológico e físico-químico, tentando assim aumentar o prazo de validade do produto comparativamente ao método de armazenamento mais tradicional, a refrigeração. O AH foi estudado e comparado com o armazenamento refrigerado e armazenamento à temperatura ambiente (0.1 MPa). Assim, diferentes temperaturas (4 e15-25 °C) e níveis de pressão (0.1, 30, 50 e 100 MPa) foram utilizados durante um período de 30 dias. Algumas amostras foram inoculadas com Listeria innocua e Escherichia coli de forma a aferir o efeito do AH para nestes microrganismos.Um segundoestudo foi também realizado com amostras embaladas de duas diferentes formas, com ar e sem ar no seu interior, numa tentativa de concluirsobre possíveis diferenças a nível microbiológico e físico-químicopotenciadas pela presença de ar na embalagem quando armazenadas sob pressão.Em ambos estudos realizaram-se análises microbiológicas (mesófilos totais, Enterobacteriaceae, coliformes epsicrófilos) e físico-químicas (pH, Aw, cor e conteúdo em lactose e açúcares redutores), para além de visualização do produto emmicroscopia eletrónica. Foram obtidosmelhores resultados no AH comparativamente à refrigeração, ocorrendo inibição de crescimento microbiano a 50 MPa e inativação de microrganismos a 100 MPa, sendo os mesofilos totais e os psicrófilos os microrganismos menos suscetíveis à pressão. No que respeita a parâmetros físico-químicos, o AHrevelou resultados semelhantes ou até melhores que a refrigeração. Assim, o AHà temperatura ambiente demonstrou ser uma possível alternativa à refrigeração para leite achocolatado, sendo esta uma metodologia amiga do ambiente uma vez que só é necessária energia na fase de compressão e descompressão, não sendo requerida para controlo de temperatura.
The main goal of this work was to study the effect of hyperbaric storage (HS) at room temperature (RT)in a chocolate milk beverage, in order to avoid its deterioration at the microbiological and physicochemical level, trying at the same time to increase its shelf life without refrigeration. HS was studied and compared with refrigeration (RF) and RT storage (0.1 MPa). The chocolate milk was stored at different temperatures (4 and 15-25 ºC) and pressure levels (0.1,30,50,100 MPa) over 30 days. Some samples were inoculated with Listeria innocua and Escherichia coli in order to study the HS effect on those microorganisms. In addition, a second study was carried out with samples packed with and without air to observe possible microbiological and physicochemical differences empowered by the presence of air. For both studies,microbiological (total aerobic mesophiles, Enterobacteriaceae, coliforms, psychrophiles), physicochemical (pH, Aw, colour, lactose and reducing sugars content) and SEM analyses were performed. HSallowed to obtain better results than RF, with a microbial growth inhibition at 50 MPa and a microbial inactivation at 100 MPa. The total aerobic mesophiles and psychrophileswere the microorganisms less susceptible to pressure. Regarding the physicochemical parameters analysed, HS showed similar or even better results than RF. Therefore, food storage under pressure (HS) at RT, demonstrated to be a possible alternative to RF for chocolate milk, being this preservation methodology environmentally friendly, since energy is only required during compression/decompression phases, not being needed for temperature control.
16
Bharadwaj, Vrushali J. "Palm Cottage Garden Historic Preservation". FIU Digital Commons, 2004. http://digitalcommons.fiu.edu/etd/1571.
Testo completoAbstract (sommario):
Historic landscapes are vital elements of our nation's cultural continuum and must be protected as a part of living fabric of the community. This thesis addressed the preservation of historic landscape gardens, focusing on design strategies that can make historic time legible in landscape. It proposed a landscape plan for the preservation of Palm Cottage Garden in Gotha, Florida, a significant historic landscape resource.
To determine the criteria used to establish how and to what period the estate should be restored, the Secretary of the Interior's Guidelines for the Treatment of Cultural Landscapes was followed. This process involved documenting the current site conditions and evaluating natural and cultural resources.
For the garden to continue to keep its historic fabric, rehabilitation was selected. The garden was designed to preserve existing features and make efficient contemporary use of the garden possible. The landscape plan focused on strategies that reveal the site's significant past through new design elements while adapting to current and future needs.
17
Imber, C. J. "Normothermic preservation of porcine livers". Thesis, University of Cambridge, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.604924.
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18
蘇立全 e Li-chuan John So. "Preservation of community during redevelopment". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1990. http://hub.hku.hk/bib/B31979774.
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Kennelly, Nicole Marie. "Historic Preservation in Lafayette, Louisiana". Thesis, University of Louisiana at Lafayette, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1557559.
Testo completoAbstract (sommario):
Historic Preservation is a continuous movement. Preservationists are responsible for the expansion of the National Register of Historic Places, as well as the care of historic buildings already listed on the National Register. This thesis explores historic preservation in Lafayette, Louisiana. The thesis is a two-part process. First, the individually listed properties on the National Register were re-evaluated to ensure that their condition is current in the nomination. Secondly, historic preservation involves discovering potential new historic properties. This process involved surveying a historic neighborhood or property. For this thesis, the survey included the historic neighborhood known locally as Freetown. The process of re-evaluation led to the discovery that certain historic buildings were altered or moved, and others are endangered. The surveys revealed an intact historic neighborhood with a sense of community that could one day be a National Historic District.
20
Odom, N. J. "Lung preservation in the rat". Thesis, University of Newcastle Upon Tyne, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234476.
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Muhammed, Suhaimi Bin. "Preservation characteristics of Malaysian timbers". Thesis, University of Aberdeen, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385151.
Testo completoAbstract (sommario):
Factors influencing the application of copper(II) and boron-based preservatives to four commercially important timbers of Malaysia viz rubberwood (Hevea brasiliensis), (Koompassia malaccensis), keruing (Dipterocarpus spp.), and dark red meranti (Shorea spp.) were studied. Of the four, only kempas contains a significant amount of extractives; the ethanol-soluble extract reacts with copper(II) solutions to form insoluble Cu(II) complexes. The anatomical features which might influence the penetrability of preservative were shown by optical and electron microscopy to be starch grains, silica grains, gums and gum ducts, tyloses and the nature of pitting on various elements. Among the boron compounds studied, the trimethyl borate-methanol azeotrope gave better impregnation and relatively higher boric acid concentration. Both gas and liquid phase treatment of rubberwood gave a relatively high concentration of boric acid near the surface and a relatively low concentration in the interior. The distribution of copper in the four woods was established by atomic absorption spectrometry and scanning electron microscopy-energy dispersive X-ray analysis. The distribution is similar to that of boric acid in rubberwood. The distribution of copper(II) and the solvent in rubberwood during drying was revealed by X-radiography and chemical analysis. It involves movement of the liquid phase and not simply of the vapour phase. The way in which the treated wood is dried greatly influences the distribution of copper. Drying via the radial and tangential faces results in a relatively high concentration of copper at the periphery leaving the centre with a relatively low concentration.
22
Wong, Debra Gail. "Modelling historic preservation tax incentives". Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/78809.
Testo completoAbstract (sommario):
Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1985.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH
Supervised by Philip B. Herr. Vita.
Includes bibliographical references (leaves 43-44).
by Debra Gail Wong.
M.C.P.
23
Manciet, Lorraine Hanna. "Microvascular dysfunction during cardiac preservation". Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184944.
Testo completoAbstract (sommario):
Heart transplantation is, for certain types of cardiovascular disease, the only form of treatment resulting in patient survival. Its clinical application is, however, limited by the shortage of donor organs. This shortage is largely due to the inability to consistently preserve adequate myocardial function over prolonged ischemic periods. It is the goal of this research to provide information which may contribute to techniques for heart preservation, thus improving graft survival following preservation and transplantation. Current methods for myocardial preservation generally involve the arrest and immersion of the heart in cold cardioplegic solution, the composition of which is designed to provide for the reduced metabolic demands of the cold, arrested muscle. These methods have extended the preservation period to approximately 6 hours; however, hearts cannot be held longer than this period because, although metabolism has been slowed by hypothermia, alterations take place which compromise functional recovery upon reperfusion. A variety of perfusates and perfusion techniques have been developed to protect the myocardium from the damage thought to occur as a consequence of ischemic storage of the isolated heart. However, a consistently successful technique for long-term preservation of the heart remains undefined. A growing body of knowledge has led to the hypothesis that injury to the microcirculation may result in myocardial ischemia during preservation and decreased contractile function following preservation. To test this hypothesis, standard Langendorff techniques for the measurement of left ventricular function were combined with biochemical, histological and morphological techniques to determine: (1) whether loss of microvascular function occurs in isolated hearts hypothermically perfused with an oxygenated solution; (2) the impact of microvascular dysfunction during the preservation period on the functional recovery of hearts; and (3) which mechanisms contribute to decreased microvascular function during preservation. This experimental approach will allow for characterization of the role of the microvasculature in decreased contractility of preserved hearts and will provide information regarding the contribution of specific mechanisms to the compromised contractility of preserved hearts. Systematic evaluation of mechanisms thought to be responsible for decreased contractility of isolated hearts could contribute to improved myocardial preservation techniques that can be applied to clinical transplantation.
24
Butz, Peter, e Bernhard Tauscher. "Emerging Technologies Towards Food Preservation". Revista de Química, 2017. http://repositorio.pucp.edu.pe/index/handle/123456789/100669.
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25
Shpak, K. "Environmental preservation or economic development?" Thesis, Вид-во СумДУ, 2006. http://essuir.sumdu.edu.ua/handle/123456789/11811.
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Muscente, Anthony Drew. "Contributions to Exceptional Fossil Preservation". Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/79659.
Testo completoAbstract (sommario):
Exceptionally preserved fossils—or fossils preserved with remains of originally non-biomineralized (i.e. soft) tissues—constitute a key resource for investigating the history of the biosphere. In comparison to fossils of biomineralized skeletal elements, which represent the majority of the fossil record but only a fraction of the total diversity that existed in the past, exceptionally preserved fossils are comparatively rare because soft tissues are rapidly destroyed in typical depositional environments.
Assemblages of such fossils, nonetheless, have received special attention among scientists in multiple fields of Earth and life sciences because they represent relatively 'complete' windows to past life. Through such windows, researchers are able to reconstruct original biological features (e.g. soft tissue anatomies) of extinct organisms and to describe the structures and compositions of ancient soft-bodied paleocommunities. To accomplish these goals, however, researchers must incorporate background information regarding the pre- and post-burial histories of exceptionally preserved fossils. In this context, my dissertation focuses on the environmental settings, diagenetic conditions, geomicrobiological activities, and weathering processes, which influence the conservation of original biological features within exceptionally preserved fossils and control their occurrences in time and space. An improved understanding of these critical factors involved in exceptional fossil preservation will ultimately our advance our knowledge regarding the history of the biosphere and the Earth system as a whole.
Each chapter of original research in this dissertation includes an innovative and distinct approach for studying exceptional fossil preservation. The second chapter describes environmental and geologic overprints in the exceptional fossil record, as revealed by a comprehensive statistical meta-analysis of a global dataset of exceptionally preserved fossil assemblages. Moving from global to specimen-based perspectives, the second and third chapters focus on minerals (products of geomicrobioloigcal, diagenetic, and weathering processes) and carbonaceous materials replicating exceptionally preserved fossils. The third chapter examines the causes of preservational variations observed among organophosphatic tubular shelly Sphenothallus fossils in the lower Cambrian of South China using an experimental approach. (Although Sphenothallus is not an exceptionally preserved fossil sensu stricto, its conservation of original organic matrix tissues in South China provides key insights into the preservation of carbonaceous material within fossils.) Lastly, the fourth chapter presents data acquired using various in situ nanoscale analytical techniques to test the hypothesis that microstructures within exceptionally preserved microfossils of the Ediacaran Doushantuo Formation of South China are some of the oldest putative cylindrical siliceous demosponge spicules in the fossil record. Collectively, these chapters describe environmental, authigenic, diagenetic, and weathering processes that affect exceptional fossil preservation, and highlight innovative methods and approaches for testing major paleobiologic and geobiologic hypotheses regarding exceptionally preserved fossils.Ph. D.
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Spencer, Maximilian. "Fuel Cell for Food Preservation". Thesis, KTH, Skolan för kemivetenskap (CHE), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-207105.
Testo completoAbstract (sommario):
As foodstuffs are being produced, transported and stored in greater quantities than ever before in human history and with an alarming amount of food products being lost to spoilage every year, new, environmentally friendly ways of preserving food products are being actively researched and developed in today’s world. Oxygen is a key pathway towards food decay and destruction, due to its dual roles as a source of respiration for the multitude of microorganisms that can cause food spoilage and through direct destruction through oxidation reactions within food products that cause oxidative deterioration. Fuel cells have the theoretical potential to be an energy efficient and environmentally friendly way of preserving food, such as fish, fruit and vegetables. Because of their nature to consume oxygen through the electrochemical reactions that produces their electrical power, they have the potential to be used to reduce localised oxygen content for the storage and transportation of foods, minimising their spoilage, as well as potentially providing electrical energy for other components in potential control systems for the fuel cell. The purpose of this project is to design and build a PEM fuel cell and examine its potential for lowering of oxygen concentrations at the gas output at the cathode. The outcome of these experiments are designed to validate the theoretical capacity of fuel cells to reduce output oxygen concentrations to levels that are able to aid in the preservation of foodstuffs. It is hoped that this study, in conjunction with the researched literature, can be used as a guide for future food shipping and storage methods. The experimental stage of this diploma work was unsatisfactory. The fuel cell was unable to produce a voltage and the reactant gases were unable to flow through the fuel cell due to a design flaw. Therefore the effectiveness of a fuel cell for depletion of oxygen to levels able to preserve food is based on the theoretical basis of the internal PEM fuel cell reactions, as well as studying past literature and patents. If the theoretical ability of the fuel cell is proven, it can be asserted that PEM fuel cells have the potential to be a real contender in the field of food preservation in shipping and storage, as well as offering greater levels of control for supplies for how and when they can ship their product. However this will require more independent research development work on the effects of low oxygen concentrations on a fuel cell operation as well as the preservation effects on a greater variety of foodstuffs. Furthermore, more research is required for more efficient and cheaper fuel cell catalysts or innovative designs are required to avoid concentration losses that arise from oxygen reduction at low oxygen levels.
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Timpson, Kellee C. "Local land preservation in Washington /". Online version, 2009. http://content.wwu.edu/cdm4/item_viewer.php?CISOROOT=/theses&CISOPTR=311&CISOBOX=1&REC=11.
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Runardotter, Mari. "On organizing for digital preservation". Doctoral thesis, Luleå : Luleå University of Technology, 2009. http://pure.ltu.se/ws/fbspretrieve/2743215.
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Fisher, Jeffrey R. "Farmland preservation in Thurston County". Online pdf file accessible through the World Wide Web, 2009. http://archives.evergreen.edu/masterstheses/Accession86-10MES/Fisher_J%20MESThesis%202009.pdf.
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So, Li-chuan John. "Preservation of community during redevelopment". Hong Kong : University of Hong Kong, 1990. http://sunzi.lib.hku.hk/hkuto/record.jsp?B25796446.
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Cloonan, Michele, e Shelby Sanett. "The Preservation of Digital Content". Johns Hopkins University Press, 2005. http://hdl.handle.net/10150/106050.
Testo completoAbstract (sommario):
The authors are conducting a three-part study to evaluate current trends in the preservation
of digital content, with an emphasis on electronic records. The study emanated from the authorsâ
work on the Preservation Task Force of the International Research on Permanent Authentic Records
in Electronic Systems (InterPARES) project. This article incorporates the findings of both the survey
and individual key-informant interviews that we conducted from August 2001 through February
2003, as round 2 of the study. Round 2 builds on the 2000â 2001 round 1 survey that sought to
identify and describe strategies for preserving electronic records. In this second round the authors
found that progress has been made in some areas while it is still lags in others.1 The full study
consists of three phases: round 1 identified and surveyed 13 institutions, projects, and programs
in North America, Australia, and Europe. Round 2 surveyed eight of the 13 institutions again to
follow up on their progress. Additionally, we interviewed 18 key informants, including archivists
and librarians. In round 3 the authors will each conduct one case study drawn from the survey
participants in rounds 1 and 2. By the end of the three rounds, the authors will have studied a
continuum of activities (over a six-year period) that constitutes a range of digital preservation
strategies. The study will have charted the change in technological developments over this periodâ
developments that have occurred in our survey institutions to meet the requirements of their
mandates to preserve digital content for as long as needed.
33
Ng, Kwok Wah 1957. "Food preservation by ionizing radiation". Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276680.
Testo completoAbstract (sommario):
The application of ionizing radiation as a preservation method for food is described and examined. The prospects and problems of introducing radiation technology for food preservation are discussed under the following aspects: (1) technical feasibilities; (2) irradiator design requirements; (3) facilities' cost analysis, and (4) legislation. Within the specified limits, ionizing radiation provides an efficacious food preservation treatment which will not lead to radioactivity induction or prejudice the safety and wholesomeness of the food. A brief introduction and description of the design approach of an industrial scale irradiator is given with an illustrative example. Assessments of the cost of radiation treatment of food of some commercially available irradiators are cited and analyzed. The international regulatory efforts and the present status of clearance, standardization and legislation of food irradiation is reviewed and discussed. It is concluded that food irradiation is ready for commercial applications and could be effectively regulated by pertinent health and safety authorities.
34
Hart, A. M. "Gauging preservation : the effects of oxidising conditions in soils on the preservation of archaeological material data". Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.603798.
Testo completoAbstract (sommario):
The development of a comparative database (CDB) based on the relative deposition of iron oxide in soils, and how this relates to variations in oxidising conditions, provides a platform for identifying differing hydrological environments within archaeological sites. The CDB is developed by using geophysical, geochemical and soil micromorphological analyses on non-archaeological sites, representing four major soil/geology types and environments. Oxidation experiments were carried out on these samples to asses the variation between differing rates of oxidation and seasonality influences. Once constructed the CDB was tested using samples taken from archaeological sites of similar soil/geology type, and includes sites ranging from the Mesolithic to the Romano-British period. Archaeological samples were collected from various features and buried soils from five sites: the Late Bronze Age enclosure at Over, the Iron Age ringwork at Wandlebury, the Iron Age enclosures at Sutton Common, the Romano-British site at Marcham-Frilford and the Bronze Age field systems at Shovel Down. The results of this project indicate that the deposition of iron oxide as identified through soil micromorphological analysis has great potential as a tool for gauging preservation of organic material in archaeological sites throughout Britain. The use of the CDB to improve the understanding of preservation and conservation issues in Britain, and beyond, will be an essential element to any future research in this field. This work will form an important part of all archaeological curators’ repertoires for assessing preservation conditions on a site, and therefore, a gauge of the appropriate level of archaeological importance and response.
35
Ingles, Maria Elena A. "Identity preservation of grain in elevators /". Search for this dissertation online, 2005. http://wwwlib.umi.com/cr/ksu/main.
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Jensen, Ryan P. "New considerations for farmland preservation techniques". Muncie, Ind. : Ball State University, 2009. http://cardinalscholar.bsu.edu/703.
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37
Olsson, Krister. "From preservation to creation of value". Doctoral thesis, KTH, Infrastructure, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3618.
Testo completoAbstract (sommario):
This report asks the question how to balance thepreservation of cultural built heritage against other publicand private interests in local planning. The aim of the studyis to contribute to knowledge about how different actors valuethe built heritage and how they interact in planning. The studydiscusses how this knowledge can be taken into account inplanning practice. As society develops further into a knowledgesociety, the valuation of local environmental qualities seemsto be more complex than during previous decades. For thatreason the maintenance of cultural built heritage is moredifficult to handle than before. The planning process has bytradition been characterised by a strong public sectorinvolvement and by strict procedural links to the regulationsystem. However, private initiatives have come to play anincreasingly important role in the planning process. Thesechanges have led to a situation where decision-making becomesinformal. The question is if planning functions in such waythat all values represented by different interests areconsidered carefully when decisions are made for preservation,renewal or change of the builtenvironment. There are reasonsto question the notion of citizen representation by localpoliticians and experts of various kinds. The theoreticalfoundation for the study is economic valuation theory, andespecially environmental economics, in combination withnegotiation theory and planning theory. These theories are usedas a starting point for an analysis of different actorsunderstanding of the cultural built heritage, their incentivesfor participating in planning, and, hence, for understandingthe interaction which determines preservation practice.Empirical findings are based on a case study of planning andheritage management in the municipality of Umeå. Itincludes studies of five recently completed planning processesconcerning specific real estate properties, as well as, aquestionnaire directed to a random selection of 1000inhabitants in the municipality. The study concludes that theoutcome of planning to a substantial part is depending of theinteraction and relations between the stakeholders, and, hence,structured by what has developed as the intellectual traditionand context of the city. The study shows that the builtenvironment seen as a public good in general is not fullyacknowledged and understood. Consequently, the private goodcharacteristic of the built environment is stressed inplanning, not only by private actors, but also by the publicsector. Furthermore, the study concludes that one importantissue in the management of the cultural built heritage is todraw on the actorsincentives for preservation, hence,paying more attention to the question of future direct andindirect use of the built heritage. An actor who primarilyfocuses on existence value runs the risk of being situated inthe margin of planning, with no real influence on decisionsconcerning heritage management.
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As'ad, Hala. "Binaural Beamforming with Spatial Cues Preservation". Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/33168.
Testo completoAbstract (sommario):
In binaural hearing aids, several beamforming algorithms can be used. These beamformers aim to enhance the target speech signal and preserve the binaural cues of the target source (e.g. with constraints on the target). However, the binaural cues of the other directional sources as well the background noise are often lost after processing. This affects the global impression of the acoustic scene, and it limits the perceptual separation of the sources by the hearing aids users. To help the hearing aids users to localize all the sound sources, it is important to keep the binaural cues of all directional sources and the background noise. Therefore, this work is devoted to find the best trade-off between the noise/interferers reduction and the cues preservations not only for the directional interferers but also for the background noise based on selection and mixing processes. In this thesis, some classification decision algorithms, which are based on different criteria such as the power, the power difference, and the coherence, are proposed to complete the selection and mixing processes. Simulations are completed using recorded signals provided by a hearing aid manufacturer to validate the performance of the proposed algorithm under different realistic acoustic scenarios. After detailed testing using different complex acoustic scenarios and different beamforming configurations, the results indicate that some of the proposed classification decision algorithms show good promise, in particular the classification decision algorithm based on coherence.
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Anilkumar, Nishtha. "ETD for Preservation : A case study". Universidad Peruana de Ciencias Aplicadas (UPC), 2012. http://hdl.handle.net/10757/622615.
Testo completoAbstract (sommario):
Conferencia realizado del 12 al 14 de setiembre en Lima, Peru del 2012 en el marco del 15º Simposio Internacional de Tesis y Disertaciones Electrónicas (ETD 2012). Evento aupiciado por la Universidad Nacional Mayor de San Marcos (UNMSM) y la Universidad Peruana de Ciencias Aplicadas (UPC).One of the reasons that we know so little of ancient life is because much of written history of those times has been lost. We can only speculate what really happened. If only we had not lost all the treasures…If only we had preserved that knowledge somewhere else or in some other medium, then probably mankind need not have to start all over again re-discovering knowledge. The loss of knowledge is due to three reasons - Disasters, Media Deterioration, and Alternative Formats & Obsolete Technology A clear idea about what could be lost will only lead us to take precautionary steps or to lessen the damage. Within a library and information service (LIS), the most likely disasters are fire or flood, but those caused by wind, earthquakes and other natural phenomena can also happen. Acts of sabotage or terrorism may occur which can destroy, or seriously disrupt the LIS. And with more and more information being held in electronic format, computer disasters, whether caused by system failure or unauthorized access and hacking into files, are becoming more common. Information is necessarily recorded on some kind of medium. All media deteriorate over time, at different rates and for different reasons. When information is provided in alternative formats – for example microforms or digitized form - equipment for using them must not only be provided, but also kept maintained in good working condition. Preserving long-term access to digital information resources is one of the key challenges facing libraries and information centers today. The paper iterates what steps have been taken by Physical Research Laboratory, Library to overcome this challenge.
40
Butler, David Stewart Barksdale. "An urban model of applied preservation". [Tampa, Fla.] : University of South Florida, 2007. http://purl.fcla.edu/usf/dc/et/SFE0002093.
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Mak, Hin-shing Ian. "Rehabilitate Sai Ying Pun through preservation". Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B39707428.
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Elliott, Jennifer. "Studies on the preservation of flowers". Thesis, University of St Andrews, 2002. http://hdl.handle.net/10023/2693.
Testo completoAbstract (sommario):
A known method for the preservation of green foliage was adapted in order to preserve floral tissues, retaining the colour and texture, thereby providing a method suitable for the preservation of whole flowers. Initially, the effects of the existing foliage preservation process on floral tissues were studied and the resulting problems of limp sticky petals and colour loss were identified. Subsequently, with a knowledge of basic plant anatomy and of the properties of the main floral pigments, the anthocyanins, a series of experiments on petals and whole flowers were carried out in an attempt to rectify these problems and to incorporate the remedies into a method for preserving whole flowers. The problem of improving the texture and firmness of flower heads was tackled by investigating the effects of adding bulking or setting ingredients to the process fluid and establishing their optimum concentrations. In the case of flower colour, the addition of acid was required in order to maintain the bright anthocyanin colours and a range of acids was investigated. Furthermore, since it is known that in nature the anthocyanin pigments are stabilised by metal ions and copigments, the use of these agents in the preservation process was also considered. This empirical work was then validated by confirming the identity of the main pigments involved and by studying various aspects of the new preservation process. Factors examined included acid concentration, temperature, solvent composition and the addition of metal ions and copigments to solutions of petal extracts containing anthocyanin pigments. Physical changes resulting from processing, including process fluid content and the moisture absorption properties of processed petals were also measured. Finally, the application of a selection of coating materials was assessed in an attempt to increase the life span of the processed flowers by providing extra protection against environmental stresses.
43
Reddy, Srikanth. "Strategies for normothermic preservation of livers". Thesis, Oxford Brookes University, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.501963.
Testo completoAbstract (sommario):
Cold preservation is currently the basis of organ preservation. However, prolonged duration of cold storage or preservation of marginal organs leads to inferior outcome. Primary non-function of liver occurs in 3.5-6% of patients requiring retransplantation. Many marginal organs such as severely steatotic livers and non-heart-beating donor livers are either not retrieved or discarded after retrieval due to concerns regards viability. A better method of preservation could enable utilisation of many of these organs and increase the donor pool. This thesis describes and demonstrates successful preservation of livers at body temperature using normothermic perfusion. It aims to make preservation physiological, improve outcomes following transplantation and increase the number of donor livers that can be transplanted by allowing use of more marginal livers.
44
San, Wai-yin, e 辛偉賢. "Community: preservation in North Point Estate". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31986754.
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Yu, Kin-ying, e 余見英. "Long term preservation of electronic documents". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B30073200.
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46
麥衍成 e Hin-shing Ian Mak. "Rehabilitate Sai Ying Pun through preservation". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B39707428.
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47
Tam, Yee-mei Agnes, e 譚懿媚. "Preservation of home of Malaysian Chinese". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/193563.
Testo completoAbstract (sommario):
The study of diaspora dictates a yearning to return home which finds its Chinese equivalent in the notion of louye-guigen ( 落葉歸根) - returning to the roots. However, reality is that diaspora comes to an end after settlement for two to three generations. We do see the prevailing trend of luodi-shenggen (落地生根) – the planting of permanent roots in the soils of different countries of Chinese overseas. In some Chinese communities, luodi-shenggen turns out to be a total assimilation while others developed a uniquely Chinese identity.
This dissertation seeks to examine how the Sinophone as ennuciative tactic to afford a sense of homeliness to the Malaysian Chinese – Mahua (馬華) who maintain a practice of Sinitic languages in their daily life for generations while they unmistakably identify themselves as Malaysian. Such identification situates them in an inbetweenness where they engage in constant dialog to engender new speech act.
Through the study of Chinese street names in George Town, Penang and the Sinophone cultural troupe Dongdiyin (動地吟), I argue that Sinitic languages afford the Malaysian Chinese a sense of home and that Sinitic languages are employed as a tactic in face of the grand narratives of their mother Chinese culture and the Malaysian national discourse, and to displace them.published_or_final_version
Literary and Cultural Studies
Master
Master of Arts
48
Ogden, Sharon Kay. "Preservation of meat by organic acids". Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339579.
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Goulding, Helen Claire. "Genesis and preservation of metalliferous sediments". Thesis, University of Southampton, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266611.
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Wheeldon, Dereck Ronald. "Donor heart preservation for heart transplantation". Thesis, Open University, 1997. http://oro.open.ac.uk/57723/.
Testo completoAbstract (sommario):
Heart transplantation has enjoyed a spectacular success over the past 25 years. Prior to 1980 less than 350 operations were carried out with an overall one year survival of less than 60%. In 1995 more than 3,000 transplants were performed with a one year survival of 83%. However, growth and improved survival have both plateaued over the last few years; the former because of the falling donor supply and the latter, in part, because of the use of less suitable donors in an effort to offset the problem of supply. Much attention has been focused on the drama of the surgery and the intricacies of immunological manipulation whilst little effort has been devoted to the area of donor management, despite the fact that primary graft failure is responsible for as many post transplant deaths as either infection or rejection. Optimum preservation of the donor heart has also provided a difficult challenge, such that, despite a considerable scientific effort little advance has been achieved to extend the 4 hour safe storage limit which has remained in place over the past 20 years. In this dissertation the problem has been approached by combining laboratory based preservation models with an objective regime of donor management. A sensitive isolated small animal working heart model was developed and used to characterise cardioplegic induction. Subsequently, the model was used to examine the interaction of oxygen content with the mode of delivery, during preservation. Finally, a number of representative solutions were combined with the most promising oxygen delivery method. These studies served to illustrate the utility of controlled laboratory studies and offer the prospect of more than doubling post storage function. The development of a rigorous donor management regime was also shown to be capable of reducing the variance in haemodynamic parameters by up to 44% whilst safely increasing the donor pool by approximately 30%. It is the contention of this thesis that the only prospect of improving the current impasse with the supply of donor hearts in sufficient quantity and of acceptable quality, is by the combination of appropriate laboratory models with controlled clinical trials.