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Mendes, Lucas William. "Metagenome of Amazon forest conversion: impacts on soil-borne microbial diversity and functions." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/64/64133/tde-11062014-144747/.
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The Amazon rainforest is considered the world\'s largest reservoir of plant and animal biodiversity, but in recent years has been subjected to high rates of deforestation for the conversion of native areas into agricultural fields and pasture. The understanding of the effects of land-use change on soil microbial communities is essential, taking into account the importance that these organisms play in the ecosystem. In this context, this thesis evaluated the effect of these changes on microorganism communities in soils under different land-use systems. In the first study, the microbial communities were analyzed using the nextgeneration sequencing Illumina Hiseq2000, considering samples from native forest, deforested area, agriculture and pasture. From the analysis of approximately 487 million sequences was possible to show that microbial communities respond differently in each landuse system, with changes in both taxonomic and functional diversity. Also, we suggested that ecosystem function in forest soils is maintained by the abundance of microorganisms, while in disturbed areas such functioning is maintained by high diversity and functional redundancy. In the second study, we assessed the extent to which a particular plant species, i.e. soybean, is able to select the microbial community that inhabits the rhizosphere. From the metagenomic sequencing by the 454 GS FLX Titanium platform we investigated the taxonomic and functional diversities of soil and rhizosphere communities associated to soybean, and also tested the validity of neutral and niche theories to explain rhizosphere community assembly process. The results suggest that soybean selects a specific microbial community inhabiting the rhizosphere based on functional traits, which may be related to benefits to the plant, such as growth promotion and nutrition. This process of selection follows largely the niche -based theory indicating the selection power of the plant and other environmental variables in shaping the microbial community both at the taxonomic and functional level. This thesis highlights the importance of microbial ecology studies in the context of the Amazon to a better understanding of the effects of deforestation on microorganisms, and provides information that can be suitable for future development of sustainable approaches for the ecosystem useA floresta Amazônica é considerada o maior reservatório de biodiversidade vegetal e animal do mundo, porém, nos últimos anos tem sido submetida à altas taxas de desmatamento para a conversão de áreas de mata nativa em campos de agricultura e pastagem. A compreensão sobre os efeitos dessa mudança de uso da terra sobre as comunidades microbianas do solo é fundamental, levando-se em consideração a importância que esses organismos desempenham no ecossistema. Neste contexto, este trabalho de tese avaliou o efeito dessas mudanças sobre as comunidades de micro-organismos em solos sob diferentes sistemas de uso. No primeiro estudo, as comunidades microbianas foram analisadas por meio do sequenciamento de nova geração Illumina Hiseq2000, sendo consideradas amostras de áreas de floresta nativa, área desmatada, agricultura e pastagem. A partir da análise de aproximadamente 487 milhões de sequências foi possível mostrar que as comunidades microbianas respondem diferentemente em cada sistema de uso do solo, com alterações tanto na diversidade taxonômica quanto funcional. Também, sugere-se que o funcionamento do ecossistema em solos de floresta é mantido pela abundância dos micro-organismos presentes, enquanto nas áreas alteradas esse funcionamento é mantido pela alta diversidade e redundância funcional. No segundo estudo foi avaliado até que ponto uma espécie de planta, i.e. soja, é capaz de selecionar a comunidade habitante de sua rizosfera. A partir do sequenciamento metagenômico pela plataforma 454 GS FLX Titanium da Roche foi investigado a diversidade taxonômica e funcional das comunidades de solo e rizosfera associadas à soja, e testou-se a validade das teorias neutras e de nicho para explicar o processo de formação das comunidades microbianas. Os resultados sugerem que a soja seleciona uma comunidade específica que habita sua rizosfera com base em atributos funcionais, os quais podem estar relacionados com benefícios à planta, como promoção do crescimento e nutrição. Esse processo de seleção segue a teoria de nicho, indicando o poder de seleção da planta e de outras variáveis ambientais em moldar as comunidades microbianas tanto de forma taxonômica quanto funcional. Esta tese destaca a importância de estudos em ecologia microbiana no contexto da Amazônia para uma melhor compreensão dos efeitos do desmatamento sobre os microrganismos e disponibiliza informações que podem ser futuramente utilizados para o desenvolvimento de metodologias mais sustentáveis para o uso do ecossistema
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Yang, Y. "Functions of SoxE in direct conversion of mouse embryonic fibroblasts (MEFs) to neurons and neural stem cell (NSC) maintenance." Thesis, University College London (University of London), 2015. http://discovery.ucl.ac.uk/1469500/.
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Proneural transcriptional factor Ascl1 plays essential roles in inducing neuronal differentiation and subtype specification in developing central nerve system. More recently, Ascl1 has been identified as one of the critical factors that are involved in direct reprogramming of fibroblasts to functional neurons. As Ascl1 is essential to activate neuronal specific programme in both neuronal differentiation and direct reprogramming, we hypothesis that identifying common Ascl1 downstream genes allows us to understand molecular mechanisms in both programmes. In this study, genome-wide expression microarrays indicated that Sox8 was involved in both Ascl1-medicate reprogramming and neural stem cell maintenance in vitro. Both Sox8 Gain-of-Function and Loss-of-Function reduced the generation of induced neurons suggested the possibility that Sox8 was transiently expressed during the reprogramming process. Furthermore, ectopic expression of Sox8 or Sox9 inhibited Ascl1-induced neuronal differentiation of neural stem cells in vitro. Sox8 or/and Sox9 Loss-of-Function significantly reduced neural stem cell proliferation in vitro. The observation was also confirmed by genome-wide expression microarray experiments, which identified a number of cell cycle related genes were deregulated by Sox8 or/and Sox9. These data suggested that SoxE (specifically Sox8 and Sox9) activities were essential to maintain neural stem cell proliferation in vitro.
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Gallon, Florian. "Moines aux extrémités de la terre : fonctions et représentations du monachisme dans la péninsule ibérique du haut moyen âge ( VIIIe - XIe siècle)." Thesis, Bordeaux 3, 2014. http://www.theses.fr/2014BOR30047.
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Cette étude vise à analyser la place occupée par les moines et les monastères, d’un double point de vue pratique et idéologique, dans la société hispanique du haut Moyen Âge, à l’exclusion de la Catalogne et d’al-Andalus. Les fonctions remplies par les monastères sont, pour une part, traditionnelles et conformes à celles qu’ils exercent à la même époque dans d’autres régions de l’Occident chrétien. Le développement du monachisme – c’est-à-dire la fondation de monastères, leur enrichissement par donation et leur capacité à se nourrir de nouvelles recrues – s’explique par la croyance en la doctrine du salut, qui incite chacun à œuvrer pour sa rédemption et celle de ses proches. Mais la profusion de monastères dans la chrétienté péninsulaire tient aussi à d’autres facteurs : stratégies économiques, politiques et mémorielles des élites ; capacité de communautés rurales solidaires à faire émaner d’elles-mêmes de modestes établissements monastiques ; progression des royaumes septentrionaux aux dépens d’al-Andalus. La prolifération des monastères est favorisée par la souplesse des cadres normatifs dans lesquels ils s’intègrent ; il en résulte une grande adaptabilité de forme et de contenu, si bien que les monasteria les plus modestes se distinguent mal de simples églises rurales, l’une de leurs fonctions essentielles étant de servir aux nécessités du culte. Les grands monastères contribuent également à l’encadrement socio-pastoral par l’emprise qu’ils exercent sur les fonctions épiscopales, par la célébration de cérémonies liturgiques ouvertes aux laïcs, par le contrôle d’églises rurales, par la réception d’immunités qui les placent à la tête de véritables seigneuries. La situation frontalière qui caractérise la péninsule Ibérique du haut Moyen Âge confère aux monastères une couleur spécifique. Victimes des assauts musulmans, ils s’engagent en retour dans la défense des territoires chrétiens. Une partie de leurs fonctions habituelles se trouve réorientée, dans un tel contexte, en des applications particulières dont témoignent l’attention au sort des captifs ou le développement, à la fin du XIe siècle, d’une liturgie belliqueuse. Les fonctions sociales remplies par les monastères et le prestige attaché au genre de vie monastique justifient que les moines occupent, en pratique, une position centrale dans le fonctionnement de la société. Celle-ci n’apparaît pourtant pas telle qu’elle laisse émerger, dans les discours, l’idée promue à la même époque par les grands monastères du nord des Pyrénées selon laquelle les moines formeraient l’élite d’une société chrétienne hiérarchisée en fonction d’un critère de pureté, et pourraient prétendre, à ce titre, occuper le sommet de l’ordre du monde. Ancré dans une tradition wisigothique qui participe à expliquer une durable imperméabilité aux courants monastiques ultra-pyrénéens, le monachisme hispanique connaît à la fin du XIe siècle un processus de normalisation qui le fait entrer dans une nouvelle phase de son histoireThis study aims to analyse, from a double practical and ideological point of view, the place of monks and monasteries in the early medieval hispanic society, apart from Catalonia and al-Andalus. The functions of monasteries were in part traditional and in keeping with the ones they fulfilled elsewhere in the christian West. The rise of monasticism – that is, the foundation of monasteries, their increase in wealth trough donations, their ability to feed themselves with new recruits – may be explained by the belief in the doctrine of salvation, which incited every one to strive for his own redemption and that of his relatives. However, the abundance of monasteries in the peninsular christendom also depended on other factors : economic, political and memorial strategies of the elite ; ability of rural communities to make appear from themselves small monasteries ; expansion of the northern realms at the expense of al-Andalus. The proliferation of monasteries was boosted by the fluidness of the normative framework in which they took place and which favoured a wide range of formal adaptation, in such a way that many modest monasteria were not easy to distinguish from simple rural churches – one of their essential functions being to serve as places of worship. The big monasteries also took part in the social control and pastoral care, thanks to the hold on the episcopal functions, celebration of liturgical ceremonies opened to lay people, ownership of rural churches and privileges of immunity that put them at the head of authentic seigniories. The border situation of the early medieval Iberian Peninsula gave to monasteries a peculiar tone. As well as they suffered from the muslim assaults, they took part in the defence of the christian territories. In such a context, part of their usual functions were redirected to specific applications, of which the attention to the lot of prisoners or the development of a bellicist liturgy at the end of the 11th century are good examples. The social functions assumed by monasteries and the prestige of the monastic way of life explain that the monks, in practical terms, held a central position in the running of society. However, this role was not enough to make emerge, in discursive terms, the idea – promoted at the same time by some big monasteries north of the Pyrenees – that the monks were the elite of a christian society hierarchically organized by a criterion of purity and claimed, for that very reason, to be at the top of the social order. The visigothic tradition in which hispanic monasticism was rooted may partly explain that it remained for long impervious to the ultra-pyrenean monastic trends. At the end of the 11th century, a process of normalization drove the iberian monasteries into a new phasis of their history
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Дмитриенко, Валерий Дмитриевич, Сергей Юрьевич Леонов, Александр Юрьевич Заковоротный, and Дмитрий Максимович Главчев. "Проблемы преобразования нелинейных систем управления технологическими процессами к эквивалентным линейным в форме Бруновского." Thesis, ВМВ, 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/45506.
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Рассматривается задача линеаризации математических моделей, описывающих технологические процессы, с целью получения удобного инструмента для управления ими. Задача линеаризации решается с помощью геометрической теории управления (ГТУ). Привлекательность ГТУ связана с получением эквивалентных нелинейным моделям линейных моделей, которые удобно использовать для решения задач управления, получая структуры регуляторов или законы управления. После чего осуществляется обратный переход из пространства линейных систем в пространство исходной нелинейной системы. При этом основные аналитические преобразования автоматизированы с помощью специализированного программного обеспечения. Поиск функций преобразования, связывающих переменные линейной и нелинейной моделей, осуществляется с помощью нового конструктивного метода решения системы дифференциальных уравнений в частных производных.The problem of linearization of mathematical models describing technological processes with the purpose of obtaining a convenient tool for managing them is considered. The problem of linearization is solved by means of a geometric control theory (GCT). The attractiveness of GCT is connected, first of all, with obtaining equivalent nonlinear linear models, which are convenient for solving management problems and receiving regulatory structures or control laws. After that performed the reverse transition from the space of linear systems to the space of the original nonlinear system. A wider application of the geometric control theory is hindered by cumbersome analytical transformations connected with the calculation of the derivatives and the Lie brackets, the definition of the involutivity of distributions, and so on, and also the problem of determining the transformation functions connecting the variables of linear models in the form of Brunovsky and initial non-linear models of control objects. The authors developed specialized software that automates the main analytical transformations of GCT. The search for the transformation functions connecting the variables of the linear and nonlinear models is carried out using a new constructive method for solving the system of partial differential equations.
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Lopes, Wagner Sanches. "A importância da utilização de múltiplas representações no desenvolvimento do conceito de função: uma proposta de ensino." Pontifícia Universidade Católica de São Paulo, 2003. https://tede2.pucsp.br/handle/handle/11233.
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This research proposes an evaluation of a didactic sequence introducing the concept of function, in particular the linear functions It is based on the elements proposed by R.Duval and B.J. Caraça. It specifically intends to evaluate the didactic phenomena which happens during the process of problem solving that involves the conversion of the graphic register of a linear functions into the algebraic and vice-versa. This research was developed in an 8th grade class of an elementary public school on the east side of São Paulo. It demonstrates the importance of making use of multiple representations in the process of developing the conceptualization of function, in order to facilitate the coordination of the various pertinent visuals, in the graphic register, and the correspondent category values in the algebraic register
Esta pesquisa constituiu-se em uma proposta de avaliação de uma seqüência didática visando a introdução ao conceito de função em particular da função afim. Fundamenta-se em elementos teóricos propostos R. Duval e B.J. Caraça. De modo mais específico pretende-se avaliar os fenômenos didáticos ocorridos na resolução de problemas envolvendo a conversão do registro gráfico de uma função afim para o algébrico e vice-versa. A proposta foi desenvolvida em uma classe de 8a série do ensino fundamental de uma escola pública na zona leste da cidade de São Paulo. Esta pesquisa revelou a importância da utilização de múltiplas representações no processo de conceitualização de função; favorecendo a coordenação entre as variáveis visuais pertinentes, no registro gráfico, e os correspondentes valores categoriais no registro algébrico
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Yassin, Ali M. "Functional conjugated systems for energy conversion and storage." Angers, 2011. http://www.theses.fr/2011ANGE0080.
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Ce travail intitulé « Systèmes Conjugués Fonctionnelle pour la Conversion et le Stockage de l'Energie » porte sur la conception et la synthèse de nouvelles classes de systems π-conjugués fonctionnels pour la conversion photovoltaïque et le développement de nouveaux matériaux microporeux. Après une présentation générales de la structure et des propriétés électroniques des principales classes de systèmes conjugués et plus particulièrement des molécules conjuguées utilisées comme matériaux donneur dans les cellules solaires organiques (CSO), le second chapitre décrit la synthèse et l'étude d'une série de donneurs moléculaires obtenus par greffage de groupes dicyanovinle sur trois types de blocs conjugués rigides : carbazole cyclopentadithiophène et dithiénopyrrole (DTP). L'évaluation de ce systèmes dans des CSOs de type hétérojonction donneur-accepteur bicouche montre que le DTP conduit aux meilleurs résultats. Une étude de l'évolution des propriétés électroniques d'une série d'oligo-DTPs avec la longueur de la chaîne confirme par ailleurs l'intérêt de ce bloc donneur pour la conception de systèmes conjugués à faible bande interdite. Le chapitre suivant traite de la synthèse d'une série de molécules conjuguées de type donneur-accepteur-donneur (D-A-D) construites autour d'un cœur isoindigo ou alcoxy-cyanobithiophène et décrit une première anlyse de leurs potentialités comme matériaux donneurs dans les CSOs. Le quatrième chapitre porte sur la synhtèse d'une séries de molécules 3D issues du greffage de groupes donneurs sur une cœur quaterthiophène de géométrie quasi-tétraédrique engendrée par effet stérique et étudie les relations entre la structure des molécules la mobilité des charges positives dans les matériaux correspondants et les performances dans des CSOs. Enfin le cinquième et dernier chapitre décrit les premières étapes vers la conception et l'utilisation de molécules conjuguées 3D en vue de développer de nouvelles classes de matériaux électroactifs microporeux par polymérisation de systèmes moléculaires 3D munis de groupes terminaux réactifsThis work entitled « Functional Conjugated Systems for Energy Conversion and Storage » involves the design and synthesis of new classes of functional π-conjugated systems for photovoltaic conversion and the development of new microporous materials. After a general introduction to the structure and electronic properties of the major classes of conjugated systems and more particularly conjugated molecules used as donor material in organic solar cells (OSC), the second chapter describes the synthesis and study of a series of molecular donors obtained by grafting dicyanovinylene on three types of conjugated rigid blocks : carbazole, cyclopentadithiophene and dithienopyrrole (DTP). The evaluation of these systems in donor-acceptor bilayer heterojunction OSCs shows that the DTP leads to best results. A study of the evolution of the electronic properties, of a series of oligo-DTPs, with the chain length further confirms the interest of the donor block for low band gap conjugated systems. The next chapter deals with the synthesis of a series of conjugated molecules of donor-acceptor-donor (D-A-D) type, built around a core of isoindigo, and describes a first evaluation of their potential as donor materials in OSCs. The fourth chapter deals with the synthesis of a series of 3D molecules derived from the grafting of donor groupas on a quaterthiophene core with a quasi-tetrehedral geometry caused by steric effect, and examine the relationship between the structure of the molecules, the mobility of positive charges in these materials and their performance in OSCs. Finally the fift and last chapter describes the first steps towards the design and use of 3D conjugated molecules in order to develop new classes of electro-active materials by polymerization of microporous 3D molecular systems provided with reactive end groups
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Lutz, Jens. "Impact of the Hydrophobic Core on PrP Function and Conversion." [S.l. : s.n.], 2008. http://nbn-resolving.de/urn:nbn:de:bsz:352-opus-61240.
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Amiri, Javad Mohammadian, and Venkata Vinod Kumar Padmanabhuni. "A Comprehensive Evaluation of Conversion Approaches for Different Function Points." Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-3691.
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Context: Software cost and effort estimation are important activities for planning and estimation of software projects. One major player for cost and effort estimation is functional size of software which can be measured in variety of methods. Having several methods for measuring one entity, converting outputs of these methods becomes important. Objectives: In this study we investigate different techniques that have been proposed for conversion between different Functional Size Measurement (FSM) techniques. We addressed conceptual similarities and differences between methods, empirical approaches proposed for conversion, evaluation of the proposed approaches and improvement opportunities that are available for current approaches. Finally, we proposed a new conversion model based on accumulated data. Methods: We conducted a systematic literature review for investigating the similarities and differences between FSM methods and proposed approaches for conversion. We also identified some improvement opportunities for the current conversion approaches. Sources for articles were IEEE Xplore, Engineering Village, Science Direct, ISI, and Scopus. We also performed snowball sampling to decrease chance of missing any relevant papers. We also evaluated the existing models for conversion after merging the data from publicly available datasets. By bringing suggestions for improvement, we developed a new model and then validated it. Results: Conceptual similarities and differences between methods are presented along with all methods and models that exist for conversion between different FSM methods. We also came with three major contributions for existing empirical methods; for one existing method (piecewise linear regression) we used a systematic and rigorous way of finding discontinuity point. We also evaluated several existing models to test their reliability based on a merged dataset, and finally we accumulated all data from literature in order to find the nature of relation between IFPUG and COSMIC using LOESS regression technique. Conclusions: We concluded that many concepts used by different FSM methods are common which enable conversion. In addition statistical results show that the proposed approach to enhance piecewise linear regression model slightly increases model’s test results. Even this small improvement can affect projects’ cost largely. Results of evaluation of models show that it is not possible to say which method can predict unseen data better than others and it depends on the concerns of practitioner that which model should be used. And finally accumulated data confirms that empirical relation between IFPUG and COSMIC is not linear and can be presented by two separate lines better than other models. Also we noted that unlike COSMIC manual’s claim that discontinuity point should be around 200 FP, in merged dataset discontinuity point is around 300 to 400. Finally we proposed a new conversion approach using systematic approach and piecewise linear regression. By testing on new data, this model shows improvement in MMRE and Pred(25).Javad Amiri: Nabshe Kooche 3, Bolvare shadi, Farhangian 2, Qom, Iran, phone: +989127476593 Vinod Kumar: s/o P.V.Kondala Rao, Main Road Khaji Street Rajahmundry. A.P. India pin: 533101 phone: +917396449336
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Huang, Mei-Chu S. "Utterance particles in Taiwanese conversation and their pragmatic functions." Virtual Press, 2002. http://liblink.bsu.edu/uhtbin/catkey/1242144.
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The discourse functions of three Taiwanese particles la, hon and ne are analyzed. These utterance particles occur primarily found in the spoken language, usually conversation. The corpus of the study comprises transcription of recorded face-to-face, telephone, and radio talk show conversation, casual interviews, and church sermons. All three Taiwanese particles express a form of emphasis but in different ways. La has five interrelated functions, depending on the context: 1. To express in an assertion and in an answer to a question; 2. To express a sense of guessing or questioning; 3. To express one's impatience, dislike, or annoyance; 4. To indicate a sense of coaxing; 5. To emphasize each item in an incomplete list. Hon expresses the lowest degree of speaker emphasis of the three particles. It is used to elicit a minimal or a positive response from the addressee. Finally, ne expresses the strongest degree of emphasis of the three. It is usually used to draw the addressee's attention to information that the speaker assumes is new to the hearer.Department of English
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Gulick, Eleanor. "Developing discourse structure analysis for use on conversations that include people with aphasia." Bowling Green State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1594159643173734.
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Zhang, Jiawei. "Multi-functional nanocomposites for the mechanical actuation and magnetoelectric conversion." Phd thesis, INSA de Lyon, 2011. http://tel.archives-ouvertes.fr/tel-00765011.
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Magnetoelectric (ME) interactions in matter correspond to the appearance of magnetization by means of an electric field (direct effect) or the appearance of electric polarization by means of a magnetic field (converse effect). The composite laminates which possess large ME coefficient, have attracted much attention in the field of sensors, modulators, switches and phase inverters. In this thesis, we report on the ME performances of the bi- and tri- layered composites. It is shown that their ME couplings can be achieved by combining magnetostrictive and piezoelectric layers. A model based on a driven damped oscillation is established for the piezoelectric/magnetostrictive laminated composite. It is used to simulate the mechanical coupling between the two layers. In addition, we report that the ME coupling can be achieved without magnetic phase but only with eddy current induced Lorentz forces in the metal electrodes of a piezoelectric material induced by ac magnetic field. The models based on the Lorentz effect inducing ME coupling in PZT unimorph bender, polyvinylidene fluoride (PVDF) film and PZT ceramic disc are thus established. The results show the good sensitivity and linear ME response versus dc magnetic field change. Thus, the room temperature magnetic field detection is achievable using the product property between magnetic forces and piezoelectricity. Besides, we report on the electrostrictive performance of cellular polypropylene electret after high-voltage corona poling. We use the Surface Potential test, Thermal Stimulated Depolarization Current experiment and Differential Scanning Calorimetry experiment to analyse its charge storage mechanism. The result show that the electrostrictive coefficient and relative permittivity of the charged samples increase. Last but not least, in order to explain this phenomenon, a mathematic model based on the charged sample has been established.
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Vanden, Hoek Amanda Lynne. "Novel function of coagulation factor Xa : conversion into a clot-dissolving cofactor." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/36854.
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PLASMIN-MEDIATED CONVERSION OF FXa INTO A CLOT-DISSOLVING COFACTOR.
Factor Xa (FXa) is an essential blood clotting enzyme. A previously identified FXa derivative, Xa33/13, is generated by two distinct cleavages by the clot-dissolving (fibrinolytic) enzyme, plasmin. FXa is first converted to FXaβ by excision of a small C-terminal peptide and then proteolyzed at Lys330 in the autolysis loop to yield Xa33/13, which cannot participate in clotting. Instead, these cleavages confer novel fibrinolytic function to Xa33/13 as a tissue plasminogen activator (tPA) cofactor, thereby accelerating plasmin generation. To understand the importance of each cleavage and the role of individual residues in this functional conversion of FXa, five mutants were generated by mutation of basic residues to glutamine: Lys330 and four residues in the β-peptide region. Mutation at Lys330 prevented autolysis loop cleavage, and this mutant dissolved purified fibrin clots faster than plasma-derived FXa derivatives. Additionally, no basic residue within the β-peptide was uniquely targeted by plasmin and no single-point mutation in this region prevented subsequent autolysis loop cleavage.
FX-DEFICIENT PATIENT.
Factor X (FX) can be activated by two separate protein complexes, known as the initiating (extrinsic) and amplifying (intrinsic) tenases, which are assembled during coagulation. I describe a FX-deficient patient with a novel compound heterozygous mutation associated with differential clotting pathway function. Quantification of plasma FX antigen revealed 15 % of normal, which was consistent with extrinsic pathway activity. Intrinsic pathway activity was reduced to 5 % of normal, suggesting an activatable specific activity 3-fold lower than expected for this branch of the clotting pathway. DNA sequence analysis identified two heterozygous mutations: (1) a previously reported mutation that disrupts the splice site between exons I and II; (2) a novel mutation resulting in an Arg386Cys substitution in the protease domain. I propose that alternate disulfide bond formation and protein folding may reduce circulating FX antigen levels. Additionally, Arg386 may be involved in substrate recognition by the intrinsic tenase complex, providing a possible explanation for the differential effect on the two branches of the coagulation cascade. Recombinant FX mutant studies confirmed our findings in patient plasma and provided further support for these hypotheses.
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Halat, David Michael. "¹⁷O Solid-state NMR spectroscopy of functional oxides for energy conversion." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/270723.
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The main aim of this thesis is the development of $^{17}$O solid-state nuclear magnetic resonance (NMR) spectroscopic techniques to study the local structure and ion dynamics of functional oxide materials for applications in energy conversion, in particular as electrodes and electrolytes in solid oxide fuel cells (SOFCs). Broadly, the work comprises two related areas: (1) application of a combined experimental and computational methodology to enable the first $^{17}$O solid-state NMR studies of paramagnetic oxides, in particular a class of perovskite-derived structures used as mixed ionic-electronic conductors (MIECs) for SOFC cathodes, and (2) further uses of multinuclear variable-temperature NMR spectroscopy, with emphasis on $^{17}$O NMR results, to elucidate mechanistic details of oxide-ion motion and sublattice exchange in a novel family of promising SOFC electrolyte materials based on $\delta$-Bi$_{2}$O$_{3}$. In the first section, $^{17}$O magic-angle spinning (MAS) NMR spectra of the paramagnetic MIEC, La$_{2}$NiO$_{4+\delta}$, are presented and rationalized with the aid of periodic DFT calculations. Advanced NMR pulse programming and quadrupolar filtering techniques are coupled to extract high-resolution spectra. In particular, these data reveal local structural distortions in La$_{2}$NiO$_{4+\delta}$ that arise from incorporation of interstitial oxide defects. Moreover, variable-temperature spectra indicate the onset of oxide-ion motion involving the interstitials at 130 °C, which is linked to an orthorhombic$-$tetragonal phase transition. By analyzing the ion dynamics on the spectral timescale, specific motional mechanisms are elucidated that prove relevant to understanding the functionality and conductivity of this phase. Next, a similar methodology is applied to the Sr-doped analogues, La$_{2-x}$Sr$_{x}$NiO$_{4+\delta}$, in an exploration of the defect chemistry and electronic structure of these phases (0 $\leq {x} \leq$ 1). By following the doping-induced evolution of spectral features assigned to interstitial and equatorial oxygen environments, changes in the ionic and electronic conductivity, respectively, are rationalized. This approach has been extended to the acquisition and assignment of $^{17}$O NMR spectra of isostructural Sm$_{2-x}$Sr$_{x}$NiO$_{4+\delta}$ and Pr$_{2-x}$Sr$_{x}$NiO$_{4+\delta}$ phases, promising SOFC cathode materials that exhibit paramagnetism on the A site (A = Sm, Pr). The final section details the characterization of oxide-ion motion in the fluorite-type phases Bi$_{1-x}$V$_{x}$O$_{1.5+x}$ and Bi$_{1-x}$P$_{x}$O$_{1.5+x}$ ($x$ = 0.087 and 0.148) developed as SOFC electrolytes. Variable-temperature NMR experiments between room temperature and 923 K reveal two distinct mechanisms. For the V-doped phases, an oxide-ion conduction mechanism is observed that involves oxygen exchange between the Bi-O sublattice and rapidly rotating VO$_{4}$ tetrahedral units. The more poorly conducting P-doped phase exhibits only vacancy conduction with no evidence of sublattice exchange, a result ascribed to the differing propensities of the dopants to undergo variable oxygen coordination. These initial insights suggest chemical design rules to improve the next generation of oxide-ion conducting materials.
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Sagaidak, Iryna. "Bi-functional materials combining energy storage and energy conversion from sunlight." Thesis, Amiens, 2019. http://www.theses.fr/2019AMIE0025.
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La nature intermittente de l'énergie solaire est souvent résolue par un couplage entre le PV et une batterie. Notre approche plus fondamentale vise à développer des matériaux capables de combiner ces deux fonctions à l'échelle moléculaire. Des nanocristaux de TiO2 de 5 nm ont été synthétisés dans notre groupe, ce qui a permis une réaction quantitative de photorecharge sous illumination standard. Nous présentons ici une étude originale portant sur l'évolution des propriétés optoélectroniques et de la dynamique du transfert de charge dans une électrode de TiO2 à l'aide d'expériences spectroscopiques in operando effectuées pendant le fonctionnement de la batterie. L'augmentation de la valeur de la bande interdite et de l'absorbance a été observée lors de l'insertion du lithium dans TiO2. Un décalage négatif en énergie de la bande de conduction indique un potentiel plus oxydant des trous photogénérés dans le Li0.6TiO2 par rapport au TiO2 initial. En analysant les processus de recombinaison dans Li0.6TiO2, nous avons établi une compétition entre les processus ultra-rapides (gamme ps) de recombinaison directe et de transfert de charge vers Ti3+ dans Li0.6TiO2, ce qui limite potentiellement le rendement de la réaction de photorécharge. Cette étude a été étendue à d'autres matériaux d'insertion généralement utilisés dans les batteries lithium-ion (Li4Ti5O12, LiCoO2, LiFePO4, MoO3, etc.). Les positions de bord de bande, la bande interdite, le type de porteurs de charge et leur concentration ont été mesurées et rassemblées dans une base de données. Basé sur ces résultats, la possibilité de photorécharge induite par la lumière a été évaluée et les premiers résultats discutésThe problem of intermittent nature of solar energy is often addressed by the traditional coupling of the PV and battery units. Our more fundamental approach targets the development of materials able to combine solar energy conversion and storage at the molecular level. The 5 nm anatase TiO2 nanocrystals were synthesized in our group affording a quantitative photorecharge reaction by a sole contribution of illumination. Here, we present a study of the evolution of the optoelectronic properties and dynamics of charge transfer in TiO2 electrode using in situ / in operando experiments performed during the battery functioning (UV-visible, Mott-Schottky, fluorescence spectroscopy). The increase of the bandgap value and the rise of absorbance are observed upon lithium insertion into TiO2. A negative shift of the conduction band indicates a more oxidizing potential of the photogenerated holes in Li0.6TiO2 compared to TiO2. By analysis of the recombination processes in TiO2 upon lithium insertion, we established a competition of the ultra-fast (ps range) processes of direct recombination and charge transfer towards Ti3+ in Li0.6TiO2, potentially limiting the yield of the photorecharge reaction. This study was extended to other insertion materials typically used in lithium-ion batteries (Li4Ti5O12, LiCoO2, LiFePO4, MoO3, etc.). The measured band edge positions, band gap, charge carrier type and concentration were gathered into a database, based on which the fundamental evaluation of the possibility of the light-induced photorecharge was conducted. The first results of the photoelectrochemical study of chosen materials are also discussed
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Otor, Hope O. "Catalyst Development and Control of Catalyst Deactivation for Carbon Dioxide Conversion." University of Toledo / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1596134702392137.
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Drusiani, Alberto. "Conversione in OCaml della libreria ocaml-gi-gtk." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/23335/.
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L’utilizzo in larga scala della libreria grafica GTK implementata in C ha forzato gli sviluppatori della stessa a rendere semplice la creazione di binding ad essa con linguaggi
di alto livello. Esistono due tipi di binding: manuale e automatico. Il binding automatico permette di svincolarsi dalle modifiche che vengono effettuate a GTK, rendendo
il processo di binding più robusto. OCaml, linguaggio di programmazione emergente e
multi-paradigma, non possiede una libreria di binding automatici per GTK scritta in
OCaml, ma una libreria scritta in Haskell chiamata ocaml-gi-gtk e sviluppata all’interno
dell’Università di Bologna.
Questo progetto ha lo scopo di convertire in OCaml questa libreria, in modo che possa
essere addottata dalla community del linguaggio. È spesso infatti presente una sorta di
tendenza all’autarchia nel mondo dei linguaggi di programmazione, che rende riluttanti
gli utilizzatori di un linguaggio nei confronti di uno simile e "concorrente"
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Lloyd, Davidson A. "The effect of forest to pasture conversion on soil biological diversity and function." Diss., Lincoln University, 2008. http://hdl.handle.net/10182/711.
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Recent declines in returns from primary forest products in New Zealand and projected increases in world food prices have led to the land-use conversion from plantation forest to pastoral farming in many lowland areas. After decades of forest cover the soils are in many cases less than adequate for pastoral farming, as they are acidic, with toxic levels of exchangeable aluminum, and contain low levels of available nitrogen (N), very high carbon (C):N ratio, and are devoid of earthworms and structural integrity. Overcoming the major site limitations of low soil pH and available N was a major priority and a field experiment was established in April 2005 to determine the impact of various rates of lime and N in relation to pasture establishment and production. Concerns about the short and long-term effects of these inputs on biological soil quality gave rise to the present study. The effects of land-use change and establishment inputs were assessed by comparison of selected treatment plots with two adjacent reference sites (long-term pasture and a 60–year Pinus radiata forest) on the same soil type. The effects of lime and N on soil biological quality were investigated under field and controlled environment conditions by determination of: microbial community structure (phospholipid fatty acids - PLFA), microbial biomass (total PLFA), and microbial activity (dehydrogenase activity). Soil physical (percentage water-stable aggregates) and chemical (pH, and total C and N) properties were also determined. Similarly, the effects of earthworm addition on soil biological properties were explored in a short-term glasshouse pot experiment. The role of earthworms as indicators of soil biological quality in the field was assumed by nematodes and these were assessed in field trial plots and the reference sites mentioned above. Land-use change and applications of lime and N contributed to changing the microbial community structure determined by principal component analysis of transformed PLFA data. However, the effect of lime was more pronounced in the field, while N contributed most to changing microbial community structure in the glasshouse. Mean microbial activity in the field increased from 4 µg dwt/hr without lime to 16 and 21 µg dwt/hr where lime was applied at 5 and 10 tons/hectare (t/ha), respectively. Mean microbial activity in the field was markedly higher (7-fold) than in the glasshouse at similar rates of lime. Lime application also increased soil moisture retention in the field, mean gravimetric soil moisture increased from 0.33 in control plots to 0.38 and 0.39 in plots treated with 5 and 10 t/ha lime, respectively. Lime application was associated with greater soil aggregate stability. Soils from test plots treated with 5 and 10 tons/ha lime had 45-50% water-stable aggregates compared to 34% in treatments without lime. After 16 weeks in pots, earthworm treatments increased mean plant dry matter (DM)/pot by at least 19% above the control. The increase was attributed primarily to greater N mineralization in the presence of earthworms. For the duration of the trial the earthworm species tested (Apporectodea caliginosa and Lumbricus rubellus, individually or combined) did not affect any of the measured soil microbial properties. However, the survival rate of A. caliginosa was 83% compared to 25% for L. rubellus. The control not receiving any lime or N and plots treated with 10t/ha lime and 200 kgN/ha had similar nematodes species composition, comprising 40% each of bacterial and fungal feeding nematodes. They differed markedly from the reference sites as the forest soil was dominated by plant associated species (38%) and the long-term pasture had 44% plant parasitic nematodes. Accordingly, the soil food web condition inferred from nematode faunal analysis characterized all test plots as basal, stressed and depleted, while the forest soil was categorized as highly structured and fungal dominated. The findings of this thesis demonstrated that land-use change from forest to pasture can have significant impacts on soil biological properties, earthworms can contribute to pasture productivity even in the short term, and nematode faunal analysis is a robust and reliable indicator of soil biological quality.
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El, Debs Bachir. "Functional single-cell hybridoma screening using droplet-based microfluidics." Strasbourg, 2011. http://www.theses.fr/2011STRA6182.
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µm de diamètre) pour la culture de cellules mammifères. On a utilisé ce système pour sélectionner spécifiquement des cellules hybridomes sécrétant des anticorps inhibant l’Enzyme de Conversion de l’Angiotensine. -1 (ECA-1). L’émulsion contenant les cellules encapsulées dans les gouttes a été incubé pendant 6 heurres pour obtenir une quantité considérable d’anticorps avec l’ECA-1. Ensuite, cette émulsion a été réinjectée dans une puce microfluidique, fusionnée avec des gouttes contenant un mélange réactionnel permettant l’obtention d’un signal fluorescent d° à l’activité de l’ECA-1. Les gouttes ayant une faible intensité de fluorescence ont été triées. Une variance considérable dans le taux d’expression d’anticorps a été constatée au niveau mono-cellulaire au sein d’une même lignée de cellules hybridomes o_ les cellules exprimant un taux élevé d’anticorps ont été isolées et cultivées. Ce système permet le criblage de 5_104 cellules par heure et pourra être utiliser pour le criblage de lymphocytes B non immortaliséesThis thesis describes a microfluidic platform allowing the functional screening of hybridoma cells on the single-cell level. In this system, individual cells from a heterogeneous population are encapsulated into aqueous microdroplets of a water-in-oil emulsion and assayed directly for the release of antibodies inhibiting drug targets. The microfluidic setup comprises a novel fully integrated chip which allows reinjection, fusion and sorting of droplets sufficiently large (~100 µm in diameter) for the cultivation of mammalian cells. We successfully used this device for the specific selection of hybridoma cells releasing antibodies inhibiting angiotensin converting enzyme-1 (ACE-1). After cell encapsulation, the resulting emulsion was incubated off-chip for 6h to obtain significant antibody concentrations. Subsequently, the droplets were reinjected into another chip, fused with a second droplet species containing all components of a fluorescence assay for ACE-1 activity, and droplets with low fluorescence intensity (indicating ACE-1 inhibition) were sorted. A wide variance in antibody expression levels at the single-cell level within a single hybridoma line was observed and high expressors could be sorted and recultivated. The approach enabled screening more than 5_104 cells per hour and should even be applicable to non-immortalized primary B-cells, as no cell proliferation is required
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Fan, Liangdong. "Development and characterization of functional composite materials for advanced energy conversion technologies." Doctoral thesis, KTH, Kraft- och värmeteknologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-134111.
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The solid oxide fuel cell (SOFC) is a potential high efficient electrochemical device for vehicles, auxiliary power units and large-scale stationary power plants combined heat and power application. The main challenges of this technology for market acceptance are associated with cost and lifetime due to the high temperature (700-1000 oC) operation and complex cell structure, i.e. the conventional membrane electrode assemblies. Therefore, it has become a top R&D goal to develop SOFCs for lower temperatures, preferably below 600 oC. To address those above problems, within the framework of this thesis, two kinds of innovative approaches are adopted. One is developing functional composite materials with desirable electrical properties at the reduced temperature, which results of the research on ceria-based composite based low temperature ceramic fuel cell (LTCFC). The other one is discovering novel energy conversion technology - Single-component/ electrolyte-free fuel cell (EFFC), in which the electrolyte layer of conventional SOFC is physically removed while this device still exhibits the fuel cell function. Thus, the focus of this thesis is then put on the characterization of materials physical and electrochemical properties for those advanced energy conversion applications. The major scientific content and contribution to this challenging field are divided into four aspects except the Introduction, Experiments and Conclusions parts. They are: Continuous developments and optimizations of advanced electrolyte materials, ceria-carbonate composite, for LTCFC. An electrolysis study has been carried out on ceria-carbonate composite based LTCFC with cheap Ni-based electrodes. Both oxygen ion and proton conductance in electrolysis mode are observed. High current outputs have been achieved at the given electrolysis voltage below 600 oC. This study also provides alternative manner for high efficient hydrogen production. Compatible and high active electrode development for ceria-carbonate composite electrolyte based LTCFC. A symmetrical fuel cell configuration is intentionally employed. The electro-catalytic activities of novel symmetrical transition metal oxide composite electrode toward hydrogen oxidation reaction and oxygen reduction reaction have been experimentally investigated. In addition, the origin of high activity of transition metal oxide composite electrode is studied, which is believed to relate to the hydration effect of the composite oxide. A novel all-nanocomposite fuel cell (ANFC) concept proposal and feasibility demonstration. The ANFC is successfully constructed by Ni/Fe-SDC anode, SDC-carbonate electrolyte and lithiated NiO/ZnO cathode at an extremely low in-situ sintering temperature, 600 oC. The ANFC manifests excellent fuel cell performance (over 550 mWcm-2 at 600 oC) and a good short-term operation as well as thermo-cycling stability. All results demonstrated its feasibility and potential for energy conversion. Fundamental study results on breakthrough research Single-Component/Electrolyte-Free Fuel Cell (EFFC) based on above nanocomposite materials (ion and semi-conductive composite) research activities. This is also the key innovation point of this thesis. Compared with classic three-layer fuel cells, EFFC with an electrolyte layer shows a much simpler but more efficient way for energy conversion. The physical-electrical properties of composite, the effects of cell configuration and parameters on cell performance, materials composition and cell fabrication process optimization, micro electrochemical reaction process and possible working principle were systematically investigated and discussed. Besides, the EFFC, joining solar cell and fuel cell working principle, is suggested to provide a research platform for integrating multi-energy-related device and technology application, such as fuel cell, electrolysis, solar cell and micro-reactor etc. This thesis provides a new methodology for materials and system innovation for the fuel cell community, which is expected to accelerate the wide implementation of this high efficient and green fuel cell technology and open new horizons for other related research fields.QC 20131122
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Othman, Nur Hidayati Binti. "Micro-structured functional catalytic ceramic hollow fibre membrane reactor for methane conversion." Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/28679.
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The most significant issue associated with the oxidative methane conversion processes is the use of pure oxygen, which is extremely expensive. By using a dense oxygen permeable membrane reactor, a possible decrease in the air separation cost can be expected due to the elimination of oxygen plants. Besides, higher reaction yields can be attained due to the selective dosing of oxygen into the reaction zone. This thesis focuses on the development and potential application of functional micro-structured catalytic ceramic hollow fibre membrane reactor (CHFMR) in oxidative methane conversion to syngas (known as partial oxidation of methane (POM)) and to ethane and ethylene (known as oxidative coupling of methane (OCM)). As the membrane reactor performance is crucially dependant on the oxygen permeation rate and good contact between oxygen and methane, two types of membrane reactor designs were proposed in this study. The first design involves the development of CHFMR that consists of two layers i.e.: an outer oxygen separation layer and an inner catalytic substrate layer, known as dual-layer catalytic hollow fibre membrane reactor (DL-CHFMR). The DL-CHFMR was fabricated via a novel single-step co-extrusion and co-sintering technique, in which the thickness and the composition of each functional layer can be controlled in order to improve reactor performance. The second design involves the development of CHFMR with an outer dense separation layer integrated with conical-shaped microchannels open at the inner surface, created via a viscous fingering induced phase inversion technique. Besides substantially reducing resistance across the membrane, the microchannels can also act as a structured substrate where catalyst can be deposited for the catalytic reaction to take place, forming a catalytic hollow fibre membrane microreactor (CHFMMR). Although the CHFMRs discussed in this study are designed particularly for POM and OCM, there are general advantages of such membrane structures and reactor designs for improving the overall reaction performance. Therefore, these reactor designs can be transferred to other important catalytic reactions.
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Wurtele, Matthew. "Ethane Conversion to Ethylene in a Direct Hydrocarbon Fuel Cell." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/38818.
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Direct hydrocarbon fuel cells are fuel cells than use hydrocarbons directly as fuel instead of the most commonly used fuel in a fuel cell, hydrogen. Studies are being done on direct hydrocarbon fuel cells because they have the potential to be energetically more efficient than hydrogen fuel cells. There are many different hydrocarbons that are available to use as a feed stock and each one reacts at different reaction rates. As the current density of a fuel cell is linked to the reaction rate, it is important to know the energetics of an oxidation reaction that is occurring. Density Functional Theory (DFT) is a technique that can be used to predict the energy states of intermediate reaction steps in a given mechanism. The focus of this study is the using DFT to explore the energetics of the oxidation of ethane to ethylene in a nickel-anode catalyst fuel cell. DFT was used in adsorption runs to optimize the geometries beginning (adsorbed ethane) and end (adsorbed ethylene) of the oxidation reaction. DFT was then used to calculate the energy of transition states by varying bond lengths. It was determined the removal of the second hydrogen from the ethyl radical is the most energy intensive step and, thus, the rate limiting step. Hydrogen, ethane, and ethylene were all explored in this study. The heats of adsorption varied from largest to smallest in the order of ethylene, hydrogen, and ethane. It was determined that the heat of adsorption of hydrogen is sufficient to meet the energy requirements for the dissociation reaction. This may help explain why hydrogen reacts so readily in fuel cells. Conversely, the heats of adsorption for the hydrocarbons did not meet the energy requirements for the dissociation reactions. This may help explain why ethane and ethylene react more slowly in a fuel cell as compared to hydrogen. Also, the oxidation of ethane to ethylene requires two large activation energies. These two additional activation energies may help explain why ethylene reacts more readily than ethane in a fuel cell.
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Xia, Lin. "Formation and function of chromate conversion coating on aircraft aluminum alloy probed by vibrational spectroscopy /." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488196781732277.
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Iyemperumal, Satish Kumar. "Conversion of Carbon Dioxide to Fuels using Dispersed Atomic-Size Catalysts." Digital WPI, 2018. https://digitalcommons.wpi.edu/etd-dissertations/505.
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Record high CO2 emissions in the atmosphere and the need to find alternative energy sources to fossil fuels are major global challenges. Conversion of CO2 into useful fuels like methanol and methane can in principle tackle both these environment and energy concerns. One of the routes to convert CO2 into useful fuels is by using supported metal catalyst. Specifically, metal atoms or clusters (few atoms large in size) supported on oxide materials are promising catalysts. Experiments have successfully converted CO2 to products like methanol, using TiO2 supported Cu atoms or clusters. How this catalyst works and how CO2 conversion could be improved is an area of much research. We used a quantum mechanical tool called density functional theory (DFT) to obtain atomic and electronic level insights in the CO2 reduction processes on TiO2 supported metal atoms and clusters.
We modeled small Cu clusters on TiO2 surface, which are experimentally synthesizable. Our results show that the interfacial sites in TiO2 supported Cu are able to activate CO2 into a bent configuration that can be further reduced. The Cu dimer was found to be the most reactive for CO2 activation but were unstable catalysts. Following Cu, we also identified other potential metal atoms that can activate CO2. Compared to expensive and rare elements like Pt, Au, and Ir, we found several early and mid transition metals to be potentially active catalysts for CO2 reduction. Because the supported metal atom or cluster is a reactive catalyst, under reaction conditions they tend to undergo aggregation and/or oxidation to form larger less active catalysts. We chose Co, Ni, and Cu group elements to study their catalyst stability under oxidizing reaction conditions. Based on the thermodynamics of Cu oxidation and kinetics of O2 dissociation, we found that TiO2 supported Cu atom or a larger Cu tetramer cluster were the likely species observed in experiments. Our work provides valuable atomic-level insights into improving the CO2 reduction activities and predicts potential catalysts for CO2 reduction to valuable fuels.
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Johannesson, Elin. "A model for heterogenic catalytic conversion of carbon dioxide to methanol." Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-167498.
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Since our society became industrialised, the levels of carbon dioxide in our atmosphere have been steadily rising, to the point where it in early 2020 at is 413 ppm. The high concentration is causing several troubling effects worldwide because of the increase in mean temperature that it creates, which causes longer draughts, more severe floods, and rising seawater levels to name a few. There are a few measures that can be taken to reduce carbon dioxide in the atmosphere, among which there are a number of methods that currently are being researched and/or used. The prospect of capturing carbon dioxide and using it as a carbon building block to make methanol is one solution that is particularly interesting, since it in theory could provide a fuel for combustion engines that is net neutral regarding carbon emission. Methanol can be synthesised from carbon dioxide using a heterogeneous catalyst consisting of copper, Cu, and zinc oxide, ZnO. This research is focused on one of the components of the catalyst, the metal oxide ZnO in the form of crystallites or nanoparticles (ZnO)n. Quantum chemistry is a branch of computational chemistry which is centered on solving the Schrödinger equation for molecular systems. Density functional theory, DFT, is an approach to quantum theory which in this study was used to calculate the geometry and energy of the particles. The supercomputer Tetralith in the National Supercomputer Centre, NSC, was used to carry out the calculations. The DFT calculations utilized the functional B3LYP and the basis set 6-31G (d,p). One of the largest particle sizes studied, (ZnO)20, with a structure that has a large, flat surface, was found to be the most energetically favourable. According to studies, the presence of an oxygen vacancy on the surface of ZnO reduces the amount of activation energy required for CO2 to bond to the particle, which increases the chance of forming CO and thus continuing the process of forming methanol. Two structures of (ZnO)20 were investigated in this regard, where oxygen atoms were removed at different locations, creating four versions of Zn20O19 in total. This proved yet again that the version with a large, flat surface yields the lesser amount of energy when an O atom is removed from the centre of its surface. The adsorption of CO2 to the ZnO clusters was studied by calculating the energy of adsorption, and this showed that it was the second version of (ZnO)20, without an O vacancy, that yielded the least amount of energy, thus being the most favourable species to engage in physisorption with CO2. Lastly, the activation energy was investigated, and a diagram of the reaction process of CO2 adsorbing to Zn20O19 forming (ZnO)20 and CO is presented in this paper, which shows that the required activation energy is 127 kJ/mol.
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Garg, Rishabh [Verfasser]. "Niobium and Tantalum Containing Heterometallic Alkoxides and Their Conversion to Functional Ceramics / Rishabh Garg." München : Verlag Dr. Hut, 2019. http://d-nb.info/1196415781/34.
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Olsson, Sverker. "Analyses of Seismic Wave Conversion in the Crust and Upper Mantle beneath the Baltic Shield." Doctoral thesis, Uppsala University, Department of Earth Sciences, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7930.
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Teleseismic data recorded by broad-band seismic stations in the Swedish National Seismic Network (SNSN) have been used in a suite of studies of seismic wave conversion in order to assess the structure of the crust and upper mantle beneath the Baltic Shield. Signals of seismic waves converted between P and S at seismic discontinuities within the Earth carry information on the velocity contrast at the converting interface, on the depth of conversion and on P and S velocities above this depth.
The conversion from P to S at the crust-mantle boundary (the Moho) provides a robust tool to constrain crustal thicknesses. Results of such analysis for the Baltic Shield show considerable variation of Moho depths and significantly improve the Moho depth map. Analysis of waves converted from S to P in the upper mantle reveals a layered lithosphere with alternating high and low velocity bodies. It also detects clear signals of a sharp velocity contrast at the lithosphere-asthenosphere boundary at depths around 200 km.
Delay times of P410s, the conversion from P to S at the upper mantle discontinuity at 410 km depth, were used in a tomographic inversion to simultaneously determine P and S velocities in the upper mantle. The polarisation of P410s was also used to study anisotropy of the upper mantle. Results of these analyses are found to be in close agreement with independently derived results from arrival time tomography and shear-wave splitting analysis of SKS.
The results presented in this thesis demonstrate the ability of converted wave analysis as a tool to detect and image geological boundaries that involve sharp contrasts in seismic properties. The results also show that this analysis can provide means of studying aspects of Earth’s structure that are conventionally studied using other types of seismic data.
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Nisar, Jawad. "Atomic Scale Design of Clean Energy Materials : Efficient Solar Energy Conversion and Gas Sensing." Doctoral thesis, Uppsala universitet, Materialteori, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-179372.
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The focus of this doctoral thesis is the atomic level design of photocatalysts and gas sensing materials. The band gap narrowing in the metal oxides for the visible-light driven photocatalyst as well as the interaction of water and gas molecules on the reactive surfaces of metal oxides and the electronic structure of kaolinite has been studied by the state-of-art calculations. Present thesis is organized into three sections. The first section discusses the possibility of converting UV active photocatalysts (such as Sr2Nb2O7, NaTaO3, SrTiO3, BiTaO4 and BiNbO4) into a visible active photocatalysts by their band gap engineering. Foreign elements doping in wide band gap semiconductors is an important strategy to reduce their band gap. Therefore, we have investigated the importance of mono- and co-anionic/cationic doping on UV active photocatalysts. The semiconductor's band edge position is calculated with respect to the water oxidation/reduction potential for various doping. Moreover, the tuning of valence and conduction band edge position is discussed on the basis of dopant's p/d orbital energy. In the second section of thesis the energetic, electronic and optical properties of TiO2, NiO and β-Si3N4 have been discussed to describe the adsorption mechanism of gas molecules at the surfaces. The dissociation of water into H+ or OH- occurs on the O-vacancy site of the (001)-surface of rutile TiO2 nanowire, which is due to the charge transfer from Ti atom to water molecule. The dissociation of water into OH- and imino (NH) groups is also observed on the β-Si3N4 (0001)-surface due to the dangling bonds of the lower coordinated N and Si surface atoms. Fixation of the SO2 molecules on the anatase TiO2 surfaces with O-deficiency have been investigated by Density Functional Theory (DFT) simulation and Fourier Transform Infrared (FTIR) spectroscopy. DFT calculations have been employed to explore the gas-sensing mechanism of NiO (100)-surface on the basis of energetic and electronic properties. In the final section the focus is to describe the optical band gap of pristine kaolinite using the hybrid functional method and GW approach. Different possible intrinsic defects in the kaolinite (001) basal surface have been studied and their effect on the electronic structure has been explained. The detailed electronic structure of natural kaolinite has been determined by the combined efforts of first principles calculations and Near Edge X-ray Absorption Fine Structure (NEXAFS).
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Kaimaki, Marianna. "Phonetic resources and interactional function in English andGreek conversation : variation and constraints." Thesis, University of York, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.507554.
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Linardopoulou, Elena. "Structure, function and evolution of human subtelomeres /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/8120.
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Li, Qiang. "Density functional theory studies of biomass conversion on metal surfaces: from small to large molecules." Doctoral thesis, Universitat Rovira i Virgili, 2017. http://hdl.handle.net/10803/461081.
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En aquesta tesi s'han proposat i calculat una sèrie de mecanismes de reacció relacionats amb diverses molècules derivades de biomassa sobre models de superficie utilitzant el paquet VASP (Vienna Ab initio simulation package).
S'ha realitzat una investigació multiescala sobre formació d'hidrogen a partir de petites molècules de metanol, etanol, etilenglicol i glicerol. Els càlculs dels alcohols C1 i C2 es realitzaren en superfícies de Cu(111) i Ru(0001), mentre que els de glicerol només sobre Ru(0001). Es van optimitzar les geometries d'enllaç dels intermedis complets, així com s'ha proposat la descomposició detallada i els mecanismes d'hidrogenació relacionats amb dites espècies. S'han analitzat les relacions BEP i TSS i s'ha realitzat també una simulació microcinètica ab initio sota diferents condicions.
Hidrogenació d'àcid levulínic a gamma-valerolactona sobre Ru(0001) i sobre Ru(0001) decorada amb HHDMA. S'ha proposat el mecanisme de formació de l'anell intramolecular sobre la superfície de Ru(0001). S'ha elucidat l'acidesa interfacial i les estructures locals a la interfície HHDMA-Ru(0001) que promouen la velocitat de catàlisi i l'estabilitat front l'oxidació.
Hidrogenació de glucosa i manosa als seus alcohols de sucre a la superfície Ru(0001). Les reaccions dels isòmers lineals i cíclics han estat calculades i comparades entre dues molècules de sucre i amb els resultats experimentals. L'autor va trobar que concentracions de diferents isòmers reactius en la fase líquida, diferents energies d'adsorció i mecanismes de reacció treballen conjuntament per controlar les velocitats de reacció totals.
Descomposició i hidrogenació de lignina a les superfícies Ni(111) i Ni(111)dopades amb Ru. S'han aclarit els mecanismes de descomposició de lignina basats en un model de dimer més complicat. S'han discutit els efectes de l'estereocentre en les seves conversions i també s’han dilucidat els efectes de dopatge de Ru promocionant el comportament dels catalitzadors.En esta tesis se han propuesto y calculado una serie de mecanismos de reacción relacionados con diversas moléculas derivadas de biomasa sobre modelos de superficie usando el paquete VASP (Vienna Ab initio simulation package). Se ha realizado una investigación multiescala sobre formación de hidrógeno a partir de moléculas pequeñas de metanol, etanol, etilenglicol y glicerol. Los cálculos de los alcoholes C1 y C2 se realizaron en superficies de Cu(111) y Ru(0001), mientras que los de glicerol sólo en Ru(0001). Se optimizaron las geometrías de enlace de los intermedios completos, así como se ha propuesto la descomposición detallada y los mecanismos de hidrogenación relacionados con dichas especies. Se han analizado las relaciones BEP y TSS y se ha realizado también una simulación microcinética ab initio en diferentes condiciones. Hidrogenación de ácido levulínico a gamma-valerolactona sobre Ru(0001) y sobre Ru(0001) decorada con HHDMA. Se ha propuesto el mecanismo de formación del anillo intramolecular en la superficie de Ru(0001). Se ha elucidado la acidez interfacial y las estructuras locales en la interfaz HHDMA-Ru(0001) que promueven la velocidad de catálisis y la estabilidad frente a la oxidación. Hidrogenación de glucosa y manosa a sus alcoholes de azúcar sobre la superficie de Ru(0001). Las reacciones de los isómeros lineales y cíclicos se han calculado y comparado entre dos moléculas de azúcar y con los resultados experimentales. El autor encontró que concentraciones de diferentes isómeros reactivos en la fase líquida, diferentes energías de adsorción y mecanismos de reacción trabajan juntos para controlar las velocidades de reacción totales. Descomposición de lignina e hidrogenación sobre superficies de Ni(111) y Ni(111) dopadas con Ru. Se han esclarecido los mecanismos de descomposición de la lignina basados en un modelo de dímero más complicado. Los efectos del estereocentro en sus conversiones se han discutido y los efectos de dopaje de Ru promocionando el comportamiento de los catalizadores también se ha aclarado.
In this thesis, a series of surface reaction mechanisms related with various biomass derived molecules on slab models have been proposed and computed by using the Vienna Ab initio simulation package (VASP). 1 Multiscale investigation of hydrogen releasing from small molecules of methanol, ethanol, ethylene glycol, and glycerol have been studied. C1 and C2 alcohols’ calculations are performed both on Cu(111) and Ru(0001) surfaces and glycerol is on Ru(0001). Complete intermediates binding geometries were optimized, detailed decomposition, hydrogenation mechanisms related with these species have been proposed. BEP and TSS relationship have been analyzed and ab initio microkinetic simulation under different conditions has been also performed. 2 Glucose and mannose hydrogenation to their sugar alcohols on Ru(0001) surface. Reactions from linear and ring isomers have been calculated and compared between two sugar molecules, and compared with experiment results. The author found that concentrations of different reactant isomers in the liquid phase, different adsorption energies and reaction mechanisms work together to control the overall reaction rates. 3 Levulinic acid hydrogenation to gamma-valerolactone on Ru(0001) and HHDMA decorated Ru(0001) surface. Intramolecular ring formation mechanism on Ru(0001) surface has been outlined. Interfacial acidity and local structures in the HHDMA-Ru(0001) interface which promote the catalysis rate and stability against oxidation have been illuminated. 4 Lignin decomposition and hydrogenation on Ni(111) and Ru doped Ni(111) surfaces. Lignin decomposition mechanisms based on more complicated dimer model have been clarified. Stereocenter effects in its conversions have been discussed and the Ru doping effects on promoting the catalysts behavior is also elucidated.
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Pedlow, Robert. "Linguistic politeness in middle childhood : its social functions, and relationships to behaviour and development /." Connect to thesis, 1997. http://eprints.unimelb.edu.au/archive/00000602.
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Nall, Shu Pin. "The functions and the ordering of conditional 'if-clauses' in English : a genre analysis." Virtual Press, 2008. http://liblink.bsu.edu/uhtbin/catkey/1395587.
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The Functions and the Ordering of Conditional `If Clauses' in English---A Genre AnalysisPrevious research studies are in agreement that the canonical order for English if conditionals is sentence-initial rather than final. However, earlier findings regarding the distribution of the ordering between initial and final if-conditionals represent only those patterns specific to the limited number of genres examined. This corpus linguistic study is based on a research approach which includes a larger sampling pool and a selection of representative genres as well as detailed statistical and content analyses. It examines the variations in the distributional patterns between initial and final if-clauses within each individual genre and across different genres. The findings of this study suggest that if-conditionals have significantly different distributional pattern across genres. In contrast to the consensus view in current literature that initial if-clause rather than final is the dominant clause order, in 3 of the genres examined in this study (Letters to the Editor, Recipes and Sports News) final if-clauses occur more frequently than initial. In addition, in 3 other genres (News Reportage, Science Fiction and Romance Fiction) these two clause types are equally distributed. This study thus identifies genre as a significant factor influencing sentential if-conditional placement.The study also argues that in addition to the expression of topic and focus discourse relations, the ordering of the conditional and consequence clauses is often used to convey specific pragmatic effects and to perform functions related to genre-specific needs, including social politeness and showing power deixis, hedging or strengthening a proposition.Department of English
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Zhang, Tianyu. "DENSITY FUNCTIONAL THEORY STUDIES ON THE STRUCTURAL EVOLUTION AND CATALYTIC REACTIVITY OF MOLYBDENUM-BASED CATALYSTS FOR METHANE CONVERSION." OpenSIUC, 2019. https://opensiuc.lib.siu.edu/dissertations/1768.
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Methane is an abundant resource existing in the form of natural and shale gas, and molybdenum-based catalysts, including molybdenum oxides and carbides, are the commonly used components in catalysts for converting methane to value-added chemicals. Therefore, understanding the catalytic mechanism underlying the methane conversion over molybdenum-based catalysts is key to designing highly efficient catalysts and optimizing the operating conditions. In this dissertation, I focus on the structural evolution from oxide to carbides and catalytic reactivity of the molybdenum-based catalysts for methane conversion based on the result from density functional theory (DFT) computational studies.First, the surface chemistry and reactivity of α-MoO3 toward C-H bond activation of methane by breaking the first C-H bond on the MoO3 (010) surface were used to evaluate various functionals of the DFT method. Our results indicate that surface reduction of α-MoO3 (010) occurs preferably through releasing the terminal oxygen atoms, generating oxygen vacancies while exposing the reduced Mo centers. These oxygen vacancies tend to be separated from each other at a higher density due to the repulsive interactions. Furthermore, the reduced α-MoO3 (010) surface promotes methane activation kinetically and thermodynamically by reducing the activation barrier for the first C-H bond breaking and stabilizing the product state as compared with those on the stoichiometric surface. There is a synergy between the reduced Mo active site and surface lattice oxygen for C-H bond cleavage. In addition, the performance of different functionals, including the pure-GGA PBE functional with the semi-empirical vdW correction and the meta-GGA SCAN functional, has been investigated. With the meta-GGA functional, we can predict the bulk structure of α-MoO3 more accurately while reproducing the thermal chemistry of MoO3. On the other hand, the reactivity based on the PBE functional is qualitatively consistent with that from the SCAN functional.We then conducted a systematic study of methane activation and conversion over the Mo-terminated surfaces derived from different phases of Mo2C carbides, i.e. the (001) surface of α-Mo2C and the (100) surface of β-Mo2C. The results show that Mo-terminated Mo2C with lower carburization in its subsurface (β-Mo2C) possesses a superior reactivity toward methane activation, resulting in a complete dissociation of methane to carbon adatom on the surface. This carbon adatom causes further carburization of the surface, lowering the reactivity toward methane activation. Moreover, the carburization occurs more easily in the near surface layers of Mo2C than in the bulk. Although carburization lowers the activities for methane activation, it promotes C-C coupling for dimerization of the (CH)ad species, resulting in (C2H2)ad on the Mo-terminated surfaces. On the deep carburized molybdenum carbide (MoC) surfaces, we mapped out the elementary steps of CH4 dissociation and possible mechanisms for forming the C2 species. The results indicate that the Mo-terminated MoC surfaces derived from different bulk phases (α- and δ-) of MoC possess a similar mechanism to that on the noble-metal surfaces for methane dissociation, i.e., CH4 dissociates sequentially to (CH)ad with both kinetic and thermodynamic feasibilities while breaking the last C-H bond in (CH)ad is highly activated. As such, C-C coupling through dimerization of the (CH)ad species occurs more readily, resulting in (C2H2)ad on the Mo-terminated surfaces. Such (C2H2)ad species can dehydrogenate easily to other C2 adsorbates such as (C2H)ad and (C2)ad. Consequently, these C2 species from CH4 dissociation will likely be the precursors for producing long chain hydrocarbons and/or aromatics on molybdenum carbide based catalysts.
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Ullah, Habib. "First-principles density functional theory study of novel materials for solar energy conversion and environment applications." Thesis, University of Exeter, 2018. http://hdl.handle.net/10871/32949.
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To design an efficient solar energy conversion device, theoretical input is extremely important to provide the basic guideline for experimental scientists, to fabricate the most efficient, cheap, and stable device with less efforts. This desire can be made possible if computational scientist use a proper theoretical protocol, design an energy material, then the experimentalist will only invest weeks or months on the synthetic effort. This thesis highlights my recent efforts in this direction. Monoclinic BiVO4 is has been using as a photocatalyst due to its stability, cheap, easily synthesizable, narrow band gap and ideal VB (-6.80 eV vs vacuum) but inappropriate CB (-4.56 eV vs vacuum) edge position, responsible for its low efficiency. We have carried out a comprehensive experimental and periodic density functional theory (DFT) simulations of the pristine, Oxygen defective (Ov), Se doped monoclinic BiVO4 and heterojunction with Selenium (Se-BiVO4), to improve not only its CB edge position but photocatalytic and charge carrier properties. It is found that Ov (1% Oxygen vacancy) and mild doped BiVO4 (1 to 2% Se) are thermodynamically stable, have ideal band edges ~ -4.30 eV), band gaps (~1.96 eV), and small effective masses of electrons and holes. We have also investigated the contribution of Se to higher performance by effecting morphology, light absorption and charge transfer properties in heterojunction. Finally, it is found that Se makes a direct Z-scheme (band alignments) with BiVO4 where the photoexcited electron of BiVO4 recombine with the VB of Se, consequences electron-hole separation at Se and BiVO4, respectively, as a result, enhanced photocurrent is obtained. Theoretical study of β-TaON in the form of primitive unit cell, supercell and its N, Ta, and O terminated surfaces are carried out with the help of periodic DFT. Optical and electronic properties of all these different species are simulated, which predict TaON as the best candidate for photocatalytic water splitting contrast to their Ta2O5 and Ta3N5 counterparts. The calculated bandgap, valence band, and conduction band edge positions predict that β-TaON should be an efficient photoanodic material. The valence band is made up of N 2p orbitals with a minor contribution from O 2p, while the conduction band is made up of Ta 5d. Turning to thin films, the valence band maximum; VBM (−6.4 eV vs. vacuum) and the conduction band minimum; CBM (−3.3 eV vs. vacuum) of (010)-O terminated surface are respectively well below and above the redox potentials of water as required for photocatalysis. Charge carriers have smaller effective masses than in the (001)-N terminated film (VBM −5.8 and CBM −3.7 eV vs. vacuum). However, due to wide band gap (3.0 eV) of (010)-O terminated surface, it cannot absorb visible wavelengths. On the other hand, the (001)-N terminated TaON thin film has a smaller band gap in the visible region (2.1 eV) but the bands are not aligned to the redox potential of water. Possibly a mixed phase material would produce an efficient photoanode for solar water splitting, where one phase performs the oxidation and the other reduction. Computational study of an optically transparent, near-infrared-absorbing low energy gap conjugated polymer, donor−acceptor−donor (D-A-D) with promising attributes for photovoltaic application is reported herein. The D and A moiety on the polymeric backbone have been found to be responsible for tuning the band gap, optical gap, open circuit (Voc) and short-circuit current density (Jsc) in the polymers solar cells (PSC). Reduction in the band gap, high charge transformation, and enhanced visible light absorption in the D-A-D system is because of strong overlapping of molecular orbitals of D and A. In addition, the enhanced planarity and weak steric hindrance between adjacent units of D-A-D, resulted in red-shifting of its onset of absorption. Finally, PSC properties of the designed D-A-D was modeled in the bulk heterojunction solar cell, which gives theoretical Voc of about 1.02 eV. DFT study has been carried out to design a new All-Solid-State dye-sensitized solar cell (SDSC), by applying a donor-acceptor conjugated polymer instead of liquid electrolyte. The typical redox mediator (I1−/I3−) is replaced with a narrow band gap, hole transporting material (HTM). A unique “upstairs” like band energy diagram is created by packing N3 between HTM and TiO2. Our theoretical simulations prove that the proposed configuration will be highly efficient as the HOMO level of HTM is 1.19 eV above the HOMO of sanitizer (dye); providing an efficient pathway for charge transfer. High short-circuit current density and power conversion efficiency is promised from the strong overlapping of molecular orbitals of HTM and sensitizer. A low reorganization energy of 0.21 eV and exciton binding energy of 0.55 eV, confirm the high efficiency of HTM. Theoretical and experimental studies of a series of four porphyrin-furan dyads were designed and synthesized, having anchoring groups, either at meso-phenyl or pyrrole-β position of a zinc porphyrin based on donor–π–acceptor (D–π–A) approach. The porphyrin macrocycle acts as donor, furan hetero cycle acts as π-spacer and either cyanoacetic acid or malonic acid group acts as acceptor. Optical bandgap, natural bonding, and molecular bonding orbital (HOMO–LUMO) analysis confirm the high efficiency pyrrole-β substituted zinc porphyrins contrast to meso-phenyl dyads. DFT study of polypyrrole-TiO2 composites has been carried out to explore their optical, electronic and charge transfer properties for the development of an efficient photocatalyst. Titanium dioxide (Ti16O32) was interacted with a range of pyrrole (Py) oligomers to predict the optimum composition of nPy-TiO2 composite with suitable band structure for efficient photocatalytic properties. The study has revealed that Py-Ti16O32 composites have narrow band gap and better visible light absorption capability compared to individual constituents. A red-shifting in λmax, narrowing band gap, and strong intermolecular interaction energy (-41 to −72 kcal/mol) of nPy-Ti16O32 composites confirm the existence of strong covalent type interactions. Electron−hole transferring phenomena are simulated with natural bonding orbital analysis where Py oligomers found as donor and Ti16O32 as an acceptor in nPy-Ti16O32 composites. Sensitivity and selectivity of polypyrrole (PPy) towards NH3, CO2 and CO have been studied at DFT. PPy oligomers are used both, in the doped (PPy+) and neutral (PPy) form, for their sensing abilities to realize the best state for gas sensing. Interaction energies and amount of charges (NBO and Mulliken charge analysis) are simulated which reveal the sensing ability of PPy towards these gases. PPy, both in doped and neutral state, is more sensitive to NH3 compared to CO2 and CO. More interestingly, NH3 causes doping of PPy and de-doping of PPy+, providing evidence that PPy/PPy+ is an excellent sensor for NH3 gas. UV-vis and UV-vis-near-IR spectra of nPy, nPy+, and nPy/nPy+-X complexes demonstrate strong interaction of PPy/PPy+ with these atmospheric gases. The applications of graphene (GR) and its derivatives in the field of composite materials for solar energy conversion, energy storage, environment purification and biosensor applications have been reviewed. The vast coverage of advancements in environmental applications of GR-based materials for photocatalytic degradation of organic pollutants, gas sensing and removal of heavy metal ions is presented. Additionally, the presences of graphene composites in the bio-sensing field have been also discussed in this review.
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Jochheim, Jörgen. "The dependence of the conversion performance of different types of diesel catalysts as a function of operation properties." [S.l. : s.n.], 1998. http://deposit.ddb.de/cgi-bin/dokserv?idn=95473792X.
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Wongtschowski, Vânia. "Conversão substancial do negócio jurídico." Pontifícia Universidade Católica de São Paulo, 2008. https://tede2.pucsp.br/handle/handle/8145.
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Previous issue date: 2008-05-26This is a master s dissertation with the objective of analyzing the conversion of legal transactions, as regulated by section 170 of the Civil Code, as follows: section 170. If however a null legal transaction contains the requirements of another, the latter shall survive if the purpose intended by the parties allows the assumption that they would have wanted it had they foreseen nullity . This section was inspired by paragraph 140 of the German Civil Code, section 393 of the Portuguese Civil Code and section 1424 of the Italian Civil Code, and is based upon the principle of maintenance of legal values, thus seeking to safeguard the relevance of transactional declarations and ensure that legal transactions may achieve their social function. Throughout the work, the author defends the idea that the purpose of the conversion of legal transactions should be perceived through a social and objective perspective, therefore removing the need to seek the internal will of the agents of the legal relationship in order to seek the practical effects that would arise out of the legal transaction were it not invalid or ineffective in an objective manner and on the basis of the transactional declaration. As such, based upon the analysis of the effects that would be achieved by such transaction, it is possible to conceive its conversion, causing the invalid or ineffective legal transaction to be perceived under a new label by means of an act of legal characterization so that effect can be given to such legal transaction. The conversion of legal transactions is consistent with the evolvement of civil law and the so-called socialization and functions of private law to the extent that it seeks to cause legal transactions achieve their social function, thus not frustrating the trust or the fair expectation of the other party or society
Trata-se de dissertação de mestrado que visa à análise do instituto da conversão do negócio jurídico, disciplinado no artigo 170 do Código Civil, com o seguinte teor: art. 170. Se, porém, o negócio jurídico nulo contiver os requisitos de outro, subsistirá este quando o fim a que visavam as partes permitir supor que o teriam querido, se tivessem previsto a nulidade . Este artigo foi inspirado no parágrafo 140 do Código Civil alemão, nos artigos 393 do Código Civil português e 1424 do Código Civil italiano, e tem como fundamento o princípio da conservação dos valores jurídicos, procurando salvaguardar a relevância da declaração negocial e garantir que o negócio jurídico possa atingir a sua função social. Sustentamos, ao longo do trabalho, que o instituto da conversão do negócio jurídico deve ser encarado sob uma perspectiva social e objetiva, eliminando-se a necessidade de se buscar a vontade interna dos sujeitos da relação jurídica, para se buscar, em uma base objetiva e tomando por base a declaração negocial, os efeitos práticos que adviriam do negócio jurídico, não fosse a sua invalidade ou ineficácia. Com base, assim, na análise dos efeitos que seriam alcançados por tal negócio, é possível se falar em sua conversão, o que fará com que o negócio inválido ou ineficaz seja encarado com uma outra roupagem, por meio de um ato de qualificação jurídica, a fim de que sejam atribuídos efeitos a tal negócio jurídico. O instituto da conversão do negócio jurídico está em consonância com a evolução do direito civil e com a chamada socialização e funcionalização do direito privado, na medida em que busca fazer com que o negócio possa atingir sua função social, não frustrando a confiança ou a justa expectativa da outra parte ou mesmo da sociedade
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Sundh, Lydia. "The function of teacher questions in EFL classroom activities in Cambodia : A conversation analytic study." Thesis, Stockholms universitet, Engelska institutionen, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-149649.
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The present study aims to examine teacher questions in an English as a foreign language (EFL) classroom with a conversation analytic (CA) approach. Specifically, the study focuses on the sequential position of the teacher questions, and on their function in the management of classroom activities. Two activities in an intermediate leveled English classroom in Cambodia with students aged 20-24 were recorded and subsequently transcribed according to CA conventions. Thereafter, the teacher questions were identified and categorized. The findings showed that there were five categories of questions used by the teacher; that is, understanding checks, activity managing questions, repair regarding understanding and repair regarding accomplishment of task and lastly topic elaboration questions. Each category of question was used in a specific time in order to manage classroom activities, however, the findings also reveal that questions can interfere with the pedagogical focus when they appear out of context and can limit students’ participation in class.
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Sanchez, del Valle Rodrigo. "In vitro direct conversion of somatic cells from the adult human brain into functional neurons by defined factors." Diss., lmu, 2013. http://nbn-resolving.de/urn:nbn:de:bvb:19-153779.
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Yu, Fu-Chen. "Reactivation Mechanism Studies on Calcium-Based Sorbents and its Applications for Clean Fossil Energy Conversion Systems." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1298957301.
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Phoenix, Danielle. "Exploring how males who encounter phenomena they identify as 'Conversion Disorder'/'Functional Neurological Disorder' experience agency in their lives." Thesis, Middlesex University, 2017. http://eprints.mdx.ac.uk/21822/.
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This research investigates the way that males who identify with the diagnostic label ‘conversion disorder/functional neurological disorder (CD/FND)’ experience agency in their lives. The historical developments, controversies and complexities around ‘CD/FND’ form the backdrop of this exploration into the lived experience of agency. A sample of eight participants were recruited via social networking sites and charities, and the data was collected through Skype-based interviews and analysed using the qualitative Interpretative Phenomenological Analysis (IPA) approach. The analysis showed the following five main themes: ‘paradox of control’, ‘living within a dualistic framework’, ‘disconnection from self and others’, ‘engaged in a battle or fight’ and ‘meaning and reality as dependent on other people’. These master themes and their related subordinate themes are presented in light of existing research. The findings highlight the difficulty experienced by participants who identify with a diagnostic label that is at odds with a medicalised approach to understanding and treating illness. The limitations of this study and the potential avenues for future research are also discussed.
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Jeffrey, Sarah Kathering. "Questioning the importance of being earnest : a conversation analysis of the use and function of humour in the serious business of therapy." Thesis, University of Hertfordshire, 2010. http://hdl.handle.net/2299/4538.
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This thesis explores the long-standing debate in the field of psychotherapy around the use of humour in psychotherapy and the shift from outcome to process research in psychotherapy research. In line with the social constructionist framework of this study, the researcher’s position is outlined. The literature review describes the link between language and the construction of both the therapeutic relationship and humour. The functions of humour in psychotherapy are outlined, and the contribution that Conversation Analysis (CA) can make in this evolution. CA, with its focus on the social action of talk, is employed on three audio-tapes of psychotherapy within this research to identify the resources drawn upon by interactants, and to examine the sequential environments in which humour arises and the responses to humorous utterances. Linguistic devices used to create humour included hyperbole, irony in conveying contrasting incongruent frames of reference, repetition, empathic self-disclosure, sarcasm, facetiousness, normalising statements, humorous impersonation and anthropomorphic personification. Humour emerged in the sequential environment of repeating and elaborating on diverging viewpoints outside of therapy. Humour in the context of persuasion and resistance functioned to dismantle client resistance and contrast their competing perspectives. Humour made in the context of uncertainty exaggerated pre-existing conversational disruption, allowing a move into repair. Humour was used to contrast new and old ways of viewing situations in the process of therapeutic change. Therapists used humour strategically to move into therapeutic tasks such as formulation, reinterpretation, lexical substitution, invitation to express emotion, praise for following an intervention and empathy. Results are discussed in relation to humour's potential place in pertinent areas of therapy such as the therapeutic relationship, empathy and emotional connectedness, unconditional positive regard, congruence, resistance, uncertainty and change. Clinical implications are summarised drawing on these concepts. Strengths and limitations of the project are outlined, future research suggested and reflections by the researcher conclude this thesis.
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McAndrew, Paula. "Investigating casual conversation: a systemic functional linguistic and social network model of analysing social reality." Australia : Macquarie University, 2002. http://hdl.handle.net/1959.14/44619.
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"November 2001".Thesis (PhD)--Macquarie University, Division of Linguistics and Psychology, Dept. of Linguistics, 2002.
Bibliography: p. 285-291.
Introduction -- Language from a systemic functional perspective -- Social networks: a review of literature relevant to the Scotland Island study -- Methodology -- Analysing relational ties: a social network perspective -- A systemic functional approach to analysing social reality -- Discussion and conclusion.
This research is concerned with the study of language and the social order. Working within the systemic functional theory of language, and utilising the concept of a social network to model the social order, the primary aim is to put on display the relationship between the linguistic system and social order, between language and culture. Systemic functional grammar (Halliday, 1995; Halliday and Hasasn, 1985/9; Halliday and Matthiesen, 1997; Eggins and Slade 1997), with its emphasis on language as a social semiotic, is used to analyse the language used by a group of four women engaged in casual conversation in a small Australian island community. Here the analysis reveals how the women negotiate their social reality when speaking to each other. It shows how their social relations are shaped within a text (Hasan, 1996), and explores the notion that, despite the seemingly trivial, unconscious nature of casual interactions, power and solidarity are continually being negotiated by the participants (Halliday, 1994; Eggins and Slade, 1997). More specifically, this research examines the notion that through lexico-grammatical and semantic selections participants are able to negotiate dominant positions in interaction. Social Network analysis has been used to examine the relationship between the individual and the group. It offers a quantifiable analytical tool for describing the character of an individual's everyday social relationships (Milroy, 1987). A social network analysis is used in the present study to map the social relationships in the tight-knit network, or speech fellowship, of these women (creating a map of the context of situation in SFL terminology). Change in the social relationships and language choices is modeled by revisiting the participants 15 months later in a contextually similar environment and re-analysing the network and linguistic options. Systemic functional linguistics is then used to highlight the interdependency of language and social order. Through systematic accounts of language and the context in which it is embedded this reciprocal nature is displayed and language and social order can be seen, not as two distinct entities, but rather as one phenomena seen from two different perspectives (Halliday, 1978; Mathiessen, 1993).
Mode of access: World Wide Web.
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Takase, Ryuichi. "Studies on Structure-Function Relationship and Conversion of Coenzyme Requirement in Bacterial α-Keto Acid Reductases Responsible for Metabolism of Acidic Polysaccharides." Kyoto University, 2015. http://hdl.handle.net/2433/200458.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第19195号
農博第2134号
新制||農||1034(附属図書館)
学位論文||H27||N4941(農学部図書室)
32187
京都大学大学院農学研究科食品生物科学専攻
(主査)教授 谷 史人, 教授 保川 清, 准教授 橋本 渉
学位規則第4条第1項該当
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Chen, Xi. "Functional food-related bioactive compounds: effect of sorghum phenolics on cancer cells in vivo and conversion of short- to long-chain omega-3 polyunsaturated fatty acids in duck liver in vivo." Diss., Kansas State University, 2017. http://hdl.handle.net/2097/38244.
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Doctor of PhilosophyDepartment of Human Nutrition
Weiqun Wang
Many functional food related bioactive compounds have been discovered and draw the attention of scientists. This dissertation focused on sorghum phenolic compounds and omega-3 polyunsaturated fatty acids. Study 1: phenolic agents in plant foods have been associated with chronic disease prevention, especially cancer. However, a direct evidence and the underlying mechanisms are mostly unknown. This study selected 13 sorghum accessions and was aim to investigate: (1) the effect of extracted sorghum phenolics on inhibiting cancer cell growth using hepatocarcinoma HepG2 and colorectal adenocarcinoma Caco-2 cell lines; (2) and the underlying mechanisms regarding cytotoxicity, cell cycle interruption, and apoptosis induction. Treatment of HepG2 and Caco-2 cells with the extracted phenolics at 0-200 M GAE (Gallic acid equivalent) up to 72 hrs resulted in a dose- and time-dependent reduction in cell number. The underlying mechanism of cell growth inhibition was examined by flow cytometry, significant inverse correlations were observed between the decreased cell number and increased cell cycle arrest at G2/M or induced apoptosis cells in both HepG2 and Caco-2 cells. The cytotoxic assay showed that the sorghum phenolic extracts were non-toxic. Although it was less sensitive, a similar inhibitory impact and underlying mechanisms were found in Caco-2 cells. These results indicated for the 1st time that a direct inhibition of either HepG2 or Caco-2 cell growth by phenolic extracts from13 selected sorghum accessions was due to cytostatic and apoptotic but not cytotoxic mechanisms. In addition, these findings suggested that sorghum be a valuable functional food by providing sustainable phenolics for potential cancer prevention. Study 2: omega-3 polyunsaturated fatty acids (ω-3 PUFAs) especially long-chain ω-3 PUFAs, have been associated with potential health benefits in chronic disease prevention. However, the conversion rate from short- to long-chain ω-3 PUFAs is limited in human body. This study was aim to assess the modification of fatty acid profiles as well as investigate the conversion of short- to long-chain ω-3 PUFAs in the liver of Shan Partridge duck after feeding various dietary fats. The experimental diets substituted the basal diet by 2% of flaxseed oil, rapeseed oil, beef tallow, or fish oil, respectively. As expected, the total ω-3 fatty acids and the ratio of total ω-3/ ω-6 significantly increased in both flaxseed and fish oil groups when compared with the control diet. No significant change of total saturated fatty acids or ω-3 fatty acids was found in both rapeseed and beef tallow groups. Short-chain ω-3 α-linolenic acid (ALA) in flaxseed oil-fed group was efficiently converted to long-chain ω-3 docosahexaenoic acid (DHA) in the duck liver. This study showed the fatty acid profiling in the duck liver after various dietary fat consumption, provided insight into a dose response change of ω-3 fatty acids, indicated an efficient conversion of short- to long-chain ω-3 fatty acid, and suggested alternative long-chain ω-3 fatty acid-enriched duck products for human health benefits. In conclusion, the two studies in this dissertation provided a fundamental understanding of anti-cancer activity by sorghum phenolic extracts and the conversion of short- to long-chain ω-3 PUFAs in duck liver, contribute to a long term goal of promoting sorghum and duck as sustainable phenolic and ω-3 PUFAs sources as well as healthy food products for human beings.
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Sharma, Vishist. "Sparse-Matrix support for the SkePU library for portable CPU/GPU programming." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-129687.
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In this thesis work we have extended the SkePU framework by designing a new container data structure for the representation of generic two dimensional sparse matrices. Computation on matrices is an integral part of many scientific and engineering problems. Sometimes it is unnecessary to perform costly operations on zero entries of the matrix. If the number of zeroes is relatively large then a requirement for more efficient data structure arises. Beyond the sparse matrix representation, we propose an algorithm to judge the condition where computation on sparse matrices is more beneficial in terms of execution time for an ongoing computation and to adapt a matrix's state accordingly, which is the main concern of this thesis work. We present and implement an approach to switch automatically between two data container types dynamically inside the SkePU framework for a multi-core GPU-based heterogeneous system. The new sparse matrix data container supports all SkePU skeletons and nearly all SkePU operations. We provide compression and decompression algorithms from dense matrix to sparse matrix and vice versa on CPU and GPUs using SkePU data parallel skeletons. We have also implemented a context aware switching mechanism in order to switch between two data container types on the CPU or the GPU. A multi-state matrix representation, and selection on demand is also made possible. In order to evaluate and test effectiveness and efficiency of our extension to the SkePU framework, we have considered Matrix-Vector Multiplication as our benchmark program because iterative solvers like Conjugate Gradient and Generalized Minimum Residual use Sparse Matrix-Vector Multiplication as their basic operation. Through our benchmark program we have demonstrated adaptive switching between two data container types, implementation selection between CUDA and OpenMP, and converting the data structure depending on the density of non-zeroes in a matrix. Our experiments on GPU-based architectures show that our automatic switching mechanism adapts with the fastest SkePU implementation variant, and has a limited training cost.
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Horodyska, Justyna [Verfasser]. "The impact on meat quality of strategies to improve feed conversion efficiency in pigs and the functional networks underpinning the relationship / Justyna Horodyska." Bonn : Universitäts- und Landesbibliothek Bonn, 2018. http://d-nb.info/1199005355/34.
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Beyazit, Selim. "Functional nanoparticles for biomedical applications." Thesis, Compiègne, 2014. http://www.theses.fr/2014COMP2163.
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Cette thèse décrit le développement de nouvelles méthodes pour obtenir des nanoparticules fonctionnelles polyvalentes qui peuvent potentiellement être utilisées pour des applications biomédicales telles que la vectorisation de médicaments, des essais biologiques et la bio-imagerie. Les nanomatériaux sont des outils polyvalents qui ont trouvé des applications comme vecteurs de médicaments, la bio-imagerie ou les biocapteurs. En particulier, les nanoparticules de type core-shell ont attiré beaucoup d'attention en raison de leur petite taille, une relation surface/volume élevée, et une biocompatibilité. Dans ce contexte, nous proposons dans la première partie de la thèse (Chapitre 2), une nouvelle méthode pour obtenir des nanoparticules core-shell via la polymérisation radicalaire en émulsion et vivante combinées. Des particules cœurs de polystyrène de 30 à 40 nm, avec une distribution de taille étroite et portant à la surface des groupements iniferter ont été utilisés pour amorcer la polymérisation supplémentaire d'une couche de polymère. Des nanoparticules core-shell ont été préparées de cette façon. Différents types d’enveloppes : anionique, zwitterioniques, à empreintes moléculaires, thermosensibles, ont ainsi été greffées. Notre méthode est une plate-forme polyvalente permettant d'ajouter des fonctionnalités multiples soit dans le noyau et/ou l'enveloppe pour les études d'interaction cellulaire et de toxicité, ainsi que des matériaux récepteurs pour l'imagerie cellulaire. Dans la deuxième partie de la thèse (Chapitre 3), nous décrivons un procédé nouveau et polyvalent pour la modification de surface des nanoparticules de conversion ascendante (UCP). Ce sont des nanocristaux fluorescents dopés de lanthanides qui ont récemment attiré beaucoup d'attention. Leur fluorescence est excitée dans le proche infrarouge, ce qui les rend idéales comme marqueurs dans des applications biomédicales telles que les tests biologiques et la bio-imagerie, l'auto-fluorescence étant réduite par rapport à des colorants organiques et les quantum dots. Cependant, les UCP sont hydrophobes et non-compatible avec les milieux aqueux, donc une modification de leur surface est essentielle. La stratégie que nous proposons utilise l'émission UV ou visible après excitation en proche infrarouge des UCP, comme source de lumière secondaire pour la photopolymérisation localisée de couches minces hydrophiles autour les UCP. Notre méthode offre de grands avantages comme la facilité d'application et la fonctionnalisation de surface rapide pour fixer divers ligands, et fournit une plateforme pour préparer des UCP encapsulée de polymères pour des différentes applications. Des hydrogels stimuli-sensibles sont des matériaux qui changent leurs propriétés physicochimiques en réponse à des stimuli externes tels que la température, le pH ou la lumière. Ces matériaux intelligents jouent un rôle critique dans des applications biomédicales telles que la vectorisation de médicaments ou l'ingénierie tissulaire. La troisième partie de cette thèse (Chapitre 4) propose un nouveau procédé de préparation d'hydrogels photo et pH sensible. Deux composantes, l'un photosensible à base dl'acide 4-[(4-méthacryloyloxy) phénylazo] benzoïque et l'autre cationic contenant des unités 2-(diéthylamino)éthyl méthacrylate, ont été synthétisés. Leur association donne des particules monodispersées de 100 nm photo et pH sensibles. Ces nanoparticules peuvent être potentiellement utilisées pour la vectorisation de médicaments, en particulier de biomolécules telles que protéines ou siARN. En conclusion, nous avons conçu plusieurs nouvelles méthodes efficaces, polyvalentes, génériques et facilement applicables pour obtenir des nanoparticules et nanocomposites de polymères fonctionnels qui peuvent être appliqués dans de différents domaines biomédicaux comme la vectorisation de médicaments, les biocapteurs, les tests biologiques et la bio-imagerieThis thesis describes the development of novel methods to obtain versatile, functional nanoparticles that can potentially be used for biomedical applications such as drug delivery, bioassays and bioimaging. Nanomaterials are versatile tools that have found applications as drug carriers, bioimaging or biosensing. In particular, core-shell type nanoparticles have attracted much attention due to their small size, high surface to volume ratio and biocompatibility. In this regard, we propose in the first part of the thesis (Chapter 2), a novel method to obtain core-shell nanoparticles via combined radical emulsion and living polymerizations. Polystyrene core seeds of 30-40 nm, with a narrow size distribution and surface-bound iniferter moieties were used to further initiate polymerization of a polymer shell. Core-shell nanoparticles were prepared in this way. Different types of shells : anionic, zwitterionic, thermoresponsive or molecularly imprinted shells, were thus grafted. Our method is a versatile platform with the ability to add multi-functionalities in either the core for optical sensing or/and the shell for cell interaction and toxicity studies, as well as receptor materials for cell imaging. In the second part of the thesis (Chapter 3), we describe a novel and versatile method for surface modification of upconverting nanoparticles (UCPs). UCPs are lanthanide-doped fluorescent nanocrystals that have recently attracted much attention. Their fluorescence is excitated in the near infrared, which makes them ideal as labels in biomedical applications such as bioimaging and bioassays, since the autofluorescence background is minimized compared to organic dyes and quantum dots. However, UCPs are hydrophobic and non-compatible with aqueous media, therefore prior surface modification is essential. The strategy that we propose makes use oft he UV or Vis emission light of near-infrared photoexcited upconverting nanoparticles, as secondary light source for the localized photopolymerization of thin hydrophilic shells around the UCPs. Our method offers great advantages like ease of application and rapid surface functionalization for attaching various ligands and therefore can provide a platform to prepare polymeric-encapsulated UCPs for applications in bioassays, optical imaging and drug delivery. Stimuli responsive hydrogels are materials that can change their physico-chemical properties in response to external stimuli such as temperature, pH or light. These smart materials play critical roles in biomedical applications such as drug delivery or tissue engineering. The third part of the thesis (Chapter 4) proposes a novel method for obtaining photo and pH-responsive supramolecularly crosslinked hydrogels. Two building blocks, one containing photoresponsive 4-[(4-methacryloyloxy)phenylazo] benzoic acid and the other, consisting of cationic 2-(diethylamino)ethyl methacrylate units, were first synthesized. Combining the two building blocks yielded photo and pH responsive monodisperse 100-nm particles. These nanoparticles can be eventually utilized for drug delivery, especially delivery of biomolecules such as siRNAs or proteins. In conclusion, we have designed several new efficient, versatile, generic and easily applicable methods to obtain functionalized polymer nanoparticles and nanocomposites that can be applied in various biomedical domains like drug delivery, biosensing, bioassays and bioimaging
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Martínez, López Juan Pablo. "Reactivity of fullerenes, endohedral metallofullerenes, and nanotubes, and their possible application in solar energy conversion." Doctoral thesis, Universitat de Girona, 2016. http://hdl.handle.net/10803/398997.
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The physical and chemical properties of fullerenes and nanotubes can be conveniently tuned by the attachment of different functional groups to them. Therefore, the systematic understanding of different problems such as chemical reactivity, catalysis, and even charge transfer can be achieved. In the current thesis, these challenges are faced transcending in interesting outcomes. That is to say, the covalent junction between chemical species and carbon nanostructures are explained in detail, thus providing a characterization of the experimentally observed products. In a second part of the thesis, the role of fullerene C60 in chemical reactions catalyzed by transition metals is elucidated. Finally, the potential applications of derivatives of fullerene C60 in the design of solar cells are illustrated. The thesis is widely supported by quantum chemistry methodology and conclusions were corroborated through experimental evidenceLes propietats físiques i químiques dels ful·lerens i nanotubs poden ser convenientment modificades mitjançant la unió de diferents grups funcionals. Per tant, és possible aconseguir la comprensió sistemàtica de diferents problemes com ara la reactivitat química, catàlisi, i fins i tot de transferència de càrrega. A la tesi actual, aquests reptes s'afronten donant lloc a resultats interessants. És a dir, la unió covalent entre espècies químiques i nanoestructures de carboni s'expliquen detalladament, proporcionant així una caracterització dels productes observats experimentalment. En una segona part de la tesi, es descriu el paper de ful·lerè C60 en les reaccions químiques catalitzades per metalls de transició. Finalment, s'il·lustren les aplicacions potencials dels derivats de ful·lerè C60 en el disseny de cèl·lules solars. La tesi és àmpliament fonamentada per metodologia de la química quàntica i les conclusions van ser corroborades a través d'evidències experimentals
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Göransson, Cornelia, and Victoria Karlsson. "Patienters uppfattning av att samtala om sexuell funktion efter stroke." Thesis, Uppsala universitet, Institutionen för folkhälso- och vårdvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-365812.
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Bakgrund: Sexuell dysfunktion kan se olika ut för personer som drabbats av stroke och kan påverka bland annat lust och sexuell tillfredsställelse hos båda könen. Patienter med stroke har uttryckt att sexualitet är ett viktigt ämne att behandla i rehabilitering efter stroke, dock har det framkommit att det är den funktionsnedsättning som ofta förbisetts av sjukvårdspersonal. Syfte: Studien syftar till att undersöka huruvida strokepatienter uppfattat att de fått samtala om sexuell funktion samt vilka faktorer som är viktiga för patienten i samband med ämnet. Detta för att identifiera eventuella förbättringsbehov gällande samtal om sexuell funktion hos patienter efter stroke. Metod:Studien gjordes utifrån en deskriptiv tvärsnittsdesign där urvalen väntrumsundersökning och systematiskt urval användes. Studien bestod av en kvantitativ enkätstudie där totalt 42 respondenter deltog. Studien har följt EPNs forskningsetiska riktlinjer. Studien genomfördes som en del av förbättringsarbetet på Rehabiliteringsmedicinska mottagningen, Akademiska sjukhuset, Uppsala. Huvudresultat: Respondenterna i studien var positiva till samtal om sexuell funktion, men endast 19% hade fått frågan. De flesta respondenter önskade att ämnet togs upp redan i slutenvården för att möjliggöra vidareutveckling av samtalet senare under rehabiliteringen. Slutsats: Det krävs mer forskning för att kunna generalisera resultatet, men utifrån den här studien kan det ses att ämnet är efterfrågat. Sjukvårdspersonal bör skapa riktlinjer för samtalets genomförande för att underlätta individanpassning samt att det ska bli en naturlig del inom omvårdnaden så att varken yngre eller äldre patienter förbises.Background:Sexual dysfunction in stroke survivors is individually and will affect, among other things, the desire and sexual satisfaction of both sexes. Stroke patients have expressed that sexuality is an important subject to treat in stroke rehabilitation, but it has been found that it is one of the disabilities that is often overlooked by healthcare professionals. Aim: The study aims to investigate whether stroke patients experienced that they have received conversations about sexual function with health care professionals and which elements that are important. This study helps to identify needs of improvements regarding conversations about sexual function in patients after stroke. Method:The study was based on a descriptive cross-sectional design using the sample study among visitors and systematic selection. The study consisted of a quantitative survey study involving a total of 42 participants. The study has followed EPN's ethical guidelines. The study was conducted as part of the improvement work at the medical rehabilitation center, Akademiska sjukhuset, Uppsala. Main result: The patients were positive about having a conversation about sexual intercourse, but only 19% of the respondents had received the question. Most respondents wanted the subject to be addressed in the early phase of acute hospitalization in order to continue working on the subject later in the rehabilitation. Conclusion:In order to generalize the results, more research is needed, but from this study it is evident that the subject is requested. Healthcare professionals should establish guidelines for conversations in order to personalize and to make it a natural part of nursing so that either young or elderly patients will be overlooked.
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Paiva, Joice Helena 1985. "Estrutura, função e estabilidade de hidrolases gicosídicas pertencentes à família GH5 com potencial aplicação na conversão de biomassa lignocelulósica em açúcares fermentáveis = Structure, function and stability of the glycosyl hidrolases that belong to GH5 family with potencial application in the conversion of lignocellulosic biomass in fermentable sugars." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/314546.
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Orientador: Mário Tyago MurakamiTese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
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Doutorado
Bioquimica
Doutora em Biologia Funcional e Molecular