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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Finding, extracting and exploiting structure in text and hypertext / Att finna, extrahera och utnyttja strukturer i text och hypertext

Ågren, Ola January 2009 (has links)
Data mining is a fast-developing field of study, using computations to either predict or describe large amounts of data. The increase in data produced each year goes hand in hand with this, requiring algorithms that are more and more efficient in order to find interesting information within a given time. In this thesis, we study methods for extracting information from semi-structured data, for finding structure within large sets of discrete data, and to efficiently rank web pages in a topic-sensitive way. The information extraction research focuses on support for keeping both documentation and source code up to date at the same time. Our approach to this problem is to embed parts of the documentation within strategic comments of the source code and then extracting them by using a specific tool. The structures that our structure mining algorithms are able to find among crisp data (such as keywords) is in the form of subsumptions, i.e. one keyword is a more general form of the other. We can use these subsumptions to build larger structures in the form of hierarchies or lattices, since subsumptions are transitive. Our tool has been used mainly as input to data mining systems and for visualisation of data-sets. The main part of the research has been on ranking web pages in a such a way that both the link structure between pages and also the content of each page matters. We have created a number of algorithms and compared them to other algorithms in use today. Our focus in these comparisons have been on convergence rate, algorithm stability and how relevant the answer sets from the algorithms are according to real-world users. The research has focused on the development of efficient algorithms for gathering and handling large data-sets of discrete and textual data. A proposed system of tools is described, all operating on a common database containing "fingerprints" and meta-data about items. This data could be searched by various algorithms to increase its usefulness or to find the real data more efficiently. All of the methods described handle data in a crisp manner, i.e. a word or a hyper-link either is or is not a part of a record or web page. This means that we can model their existence in a very efficient way. The methods and algorithms that we describe all make use of this fact. / Informationsutvinning (som ofta kallas data mining även på svenska) är ett forskningsområde som hela tiden utvecklas. Det handlar om att använda datorer för att hitta mönster i stora mängder data, alternativt förutsäga framtida data utifrån redan tillgänglig data. Eftersom det samtidigt produceras mer och mer data varje år ställer detta högre och högre krav på effektiviteten hos de algoritmer som används för att hitta eller använda informationen inom rimlig tid. Denna avhandling handlar om att extrahera information från semi-strukturerad data, att hitta strukturer i stora diskreta datamängder och att på ett effektivt sätt rangordna webbsidor utifrån ett ämnesbaserat perspektiv. Den informationsextraktion som beskrivs handlar om stöd för att hålla både dokumentationen och källkoden uppdaterad samtidigt. Vår lösning på detta problem är att låta delar av dokumentationen (främst algoritmbeskrivningen) ligga som blockkommentarer i källkoden och extrahera dessa automatiskt med ett verktyg. De strukturer som hittas av våra algoritmer för strukturextraktion är i form av underordnanden, exempelvis att ett visst nyckelord är mer generellt än ett annat. Dessa samband kan utnyttjas för att skapa större strukturer i form av hierarkier eller riktade grafer, eftersom underordnandena är transitiva. Det verktyg som vi har tagit fram har främst använts för att skapa indata till ett informationsutvinningssystem samt för att kunna visualisera indatan. Huvuddelen av den forskning som beskrivs i denna avhandling har dock handlat om att kunna rangordna webbsidor utifrån både deras innehåll och länkarna som finns mellan dem. Vi har skapat ett antal algoritmer och visat hur de beter sig i jämförelse med andra algoritmer som används idag. Dessa jämförelser har huvudsakligen handlat om konvergenshastighet, algoritmernas stabilitet givet osäker data och slutligen hur relevant algoritmernas svarsmängder har ansetts vara utifrån användarnas perspektiv. Forskningen har varit inriktad på effektiva algoritmer för att hämta in och hantera stora datamängder med diskreta eller textbaserade data. I avhandlingen presenterar vi även ett förslag till ett system av verktyg som arbetar tillsammans på en databas bestående av “fingeravtryck” och annan meta-data om de saker som indexerats i databasen. Denna data kan sedan användas av diverse algoritmer för att utöka värdet hos det som finns i databasen eller för att effektivt kunna hitta rätt information. / AlgExt, CHiC, ProT
2

Contribui??o ao desenvolvimento de ontologias para processos petroqu?micos : estudo de caso em uma planta DEA

Diniz, Anthony Andrey Ramalho 03 September 2010 (has links)
Made available in DSpace on 2014-12-17T14:08:41Z (GMT). No. of bitstreams: 1 AnthonyARD_DISSERT.pdf: 2982432 bytes, checksum: 71a6d988a19819a67932642761ac3dda (MD5) Previous issue date: 2010-09-03 / In the last decades, the oil, gas and petrochemical industries have registered a series of huge accidents. Influenced by this context, companies have felt the necessity of engaging themselves in processes to protect the external environment, which can be understood as an ecological concern. In the particular case of the nuclear industry, sustainable education and training, which depend too much on the quality and applicability of the knowledge base, have been considered key points on the safely application of this energy source. As a consequence, this research was motivated by the use of the ontology concept as a tool to improve the knowledge management in a refinery, through the representation of a fuel gas sweetening plant, mixing many pieces of information associated with its normal operation mode. In terms of methodology, this research can be classified as an applied and descriptive research, where many pieces of information were analysed, classified and interpreted to create the ontology of a real plant. The DEA plant modeling was performed according to its process flow diagram, piping and instrumentation diagrams, descriptive documents of its normal operation mode, and the list of all the alarms associated to the instruments, which were complemented by a non-structured interview with a specialist in that plant operation. The ontology was verified by comparing its descriptive diagrams with the original plant documents and discussing with other members of the researchers group. All the concepts applied in this research can be expanded to represent other plants in the same refinery or even in other kind of industry. An ontology can be considered a knowledge base that, because of its formal representation nature, can be applied as one of the elements to develop tools to navigate through the plant, simulate its behavior, diagnose faults, among other possibilities / Nas ?ltimas d?cadas, o segmento de ?leo & g?s e petroqu?mica tem registrado uma s?rie de grandes acidentes. Influenciadas por esse contexto, as empresas tem sentido a necessidade de se engajar em processos de prote??o do ambiente externo, que se traduz na preocupa??o ecol?gica. No caso particular da ind?stria nuclear mundial, a educa??o sustent?vel e o treinamento, que dependem muito da qualidade e utilidade da base de conhecimento, t?m sido considerados pontos chave para utiliza??o desse tipo de energia com seguran?a. Dessa forma, a motiva??o dessa pesquisa foi aplicar o conceito de ontologia como ferramenta para melhorar a gest?o do conhecimento em uma refinaria, atrav?s da representa??o de uma planta de ado?amento de g?s combust?vel, condensando os v?rios tipos informa??es associados com o seu modo de opera??o normal. Em termos de metodologia, este estudo pode ser classificado como uma pesquisa aplicada e descritiva, em que foram analisadas, classificadas e interpretadas informa??es que possibilitaram criar a ontologia descritiva de uma planta real. A modelagem da planta DEA foi realizada de acordo com os fluxogramas de processo, fluxogramas de tubula??o e instrumenta??o, documentos descritivos de seu modo de opera??o e a rela??o de alarmes associados, que foram complementadas com uma entrevista n?o estruturada de um especialista em seu modo de opera??o. A valida??o aconteceu atrav?s da compara??o de grafos montados a partir da ontologia com a documenta??o original e debatidos com o grupo de trabalho. Os conceitos utilizados nesta pesquisa podem ser expandidos para representar outras plantas da pr?pria refinaria ou mesmo de outras ind?strias. A ontologia pode ser considerada uma base de conhecimento, que devido ao seu car?ter formal, pode ser aplicada como um dos elementos no desenvolvimento de ferramentas de navega??o da planta, simula??o de comportamento, diagn?stico de falhas, dentre outras possibilidades
3

Etude de la phosphorylation et de l'internalisation des r¨¦cepteurs VPAC.

Langlet, Christelle 24 June 2005 (has links)
Le VIP (ou vasoactive intestinal peptide) est un neuropeptide actif au niveau du syst¨¨me nerveux central et p¨¦riph¨¦rique (syst¨¨mes cardiovasculaire, respiratoire, tractus gastro-intestinal¡­). Il agit sur ces tissus cibles par interaction avec les r¨¦cepteurs VPAC1 et VPAC2, pour lesquels il poss¨¨de une haute affinit¨¦. Ces r¨¦cepteurs appartiennent ¨¤ la classe II des r¨¦cepteurs ¨¤ 7 h¨¦lices transmembranaires coupl¨¦s aux prot¨¦ines G, distincte de celle des r¨¦cepteurs apparent¨¦s ¨¤ la rhodopsine. En r¨¦ponse au VIP, ils stimulent pr¨¦f¨¦rentiellement l'ad¨¦nylate cyclase. Seul le r¨¦cepteur VPAC1 est capable, lorsqu'il est exprim¨¦ ¨¤ haute concentration, d¡¯augmenter les concentrations de calcium intracellulaire : G*i participe ¨¤ cette interaction. L'exposition des deux r¨¦cepteurs au VIP n'aboutit pas seulement ¨¤ leur activation : elle induit une succession de m¨¦canismes cellulaires intrins¨¨ques responsables d'une diminution de la capacit¨¦ du r¨¦cepteur ¨¤ r¨¦pondre ¨¤ un agoniste : la d¨¦sensibilisation. Diff¨¦rents processus peuvent contribuer ¨¤ la d¨¦sensibilisation d¡¯un r¨¦cepteur : le d¨¦couplage du r¨¦cepteur de la prot¨¦ine G, la s¨¦questration du r¨¦cepteur, ou encore leur "down regulation", r¨¦sultat ¨¤ plus long terme de la perte d'une partie du pool total de r¨¦cepteurs. Les m¨¦canismes impliqu¨¦s d¨¦pendent du r¨¦cepteur consid¨¦r¨¦ et de l'¨¦quipement prot¨¦ique de la cellule. Il a ¨¦t¨¦ r¨¦cemment montr¨¦ que le r¨¦cepteur VPAC1 humain ¨¦tait phosphoryl¨¦ (en position S447) en r¨¦ponse ¨¤ l¡¯agoniste, que la ¦Â-arrestine ¨¦tait transloqu¨¦e ¨¤ la membrane plasmique et que l¡¯internalisation qui s¡¯en suivait induisait un ph¨¦nom¨¨ne dynamine-d¨¦pendant. Aucune information plus pr¨¦cise n¡¯est r¨¦f¨¦r¨¦e dans la litt¨¦rature. Ce travail de th¨¨se a donc consist¨¦ en une ¨¦tude plus approfondie de la phosphorylation, l¡¯internalisation et la r¨¦cup¨¦ration du r¨¦cepteur VPAC1 humain. Dans un premier temps, nous nous sommes consacr¨¦ ¨¤ l¡¯¨¦laboration d¡¯un anticorps monoclonal sp¨¦cifique anti-r¨¦cepteur afin de visualiser le r¨¦cepteur. Nous avons eu recours ¨¤ l¡¯immunisation g¨¦n¨¦tique qui consiste ¨¤ injecter l¡¯antig¨¨ne sous forme d¡¯ADN. Une majorit¨¦ des souris immunis¨¦es ont produit des anticorps. L¡¯une d¡¯entre-elle a permis de g¨¦n¨¦rer un anticorps monoclonal, lequel a ¨¦t¨¦ compl¨¨tement caract¨¦ris¨¦ : les r¨¦sultats obtenus par FACS montrent qu¡¯il est sp¨¦cifique, s¨¦lectif et que son ¨¦pitope est localis¨¦e au sein de l¡¯extr¨¦mit¨¦ amino-terminale du r¨¦cepteur (figure 1). Il n¡¯interf¨¨rent pas avec la liaison du ligand et ne modifie en rien l¡¯activation du r¨¦cepteur par celui-ci. Cet anticorps monoclonal ne permet pas de d¨¦tecter le r¨¦cepteur par Western Blott, mais est capable de l¡¯immunopr¨¦cipiter. Dans un second temps, nous avons abord¨¦ l¡¯¨¦tude de la phosphorylation, de l¡¯internalisation et du trafficking du r¨¦cepteur VPAC1 humain.
4

An?lise de componentes prot?ticos conceito switching : conformidade de adapta??o e teste mec?nico de fadiga

Bondan, Jo?o Lopes 01 September 2017 (has links)
Submitted by PPG Odontologia (odontologia-pg@pucrs.br) on 2017-10-03T18:59:24Z No. of bitstreams: 1 JOAO_LOPES_BONDAN_TES.pdf: 2172429 bytes, checksum: ffea0ba74b477c238faf42ea29d200db (MD5) / Rejected by Caroline Xavier (caroline.xavier@pucrs.br), reason: Devolvido devido ? falta de capa institucional no arquivo PDF. on 2017-10-04T13:38:51Z (GMT) / Submitted by PPG Odontologia (odontologia-pg@pucrs.br) on 2017-10-05T17:15:31Z No. of bitstreams: 1 JOAO_LOPES_BONDAN_TES.pdf: 2360015 bytes, checksum: b0622efe2634c60233691e20bf7f7283 (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-10-06T12:13:53Z (GMT) No. of bitstreams: 1 JOAO_LOPES_BONDAN_TES.pdf: 2360015 bytes, checksum: b0622efe2634c60233691e20bf7f7283 (MD5) / Made available in DSpace on 2017-10-06T12:16:18Z (GMT). No. of bitstreams: 1 JOAO_LOPES_BONDAN_TES.pdf: 2360015 bytes, checksum: b0622efe2634c60233691e20bf7f7283 (MD5) Previous issue date: 2017-09-01 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The aim of this study was to analyze both the adaptation conformity of switching platform prosthetic components and their behavior in fatigue mechanical tests. The subject was split into two manuscripts according to the scope of two specific journals in the area of oral rehabilitation. The manuscript 1 presents a literature review that enlightened concepts related to the usage of the switching platform and its biological benefits demonstrated in the literature. However, factors associated with the biomechanical stability provided by this new concept have shown to be a coarsely explored area by science. Thus, such factors need to be better understood and confirmed by studies evaluating biomechanical issues of this platform. After demonstrating this shortage in the literature review, a laboratory study started, aiming at responding questions linked to the long term prosthetic stability. The manuscript 2 assessed the adaptation conformity of switching components confronted to mechanical cycling tests. The methodology was based on 40 prosthetic components for unity rehabilitations on implants standard HE 4.1 RP, being divided in four groups: 10 components UCLA 4.1 mm (group UC 4.1), 10 components UCLA 3.6 mm (group UC 3.6) , 10 components type conic abutment 4.1 mm (group AC 4.1) and 10 conic abutment 3.6 mm (group AC 3.6) on the respective implant standard RP HE 4.1 mm. The groups have been evaluated by Energy Dispersive Spectroscopy (EDS) to confirm the manufacture standard of the samples. Scanning electronic microscopy (SEM) was used to evaluate the adaptation in the vertical (FV) and horizontal (DH) directions. For the statistical analysis of the FV data, Kruskal-wallis and Crosstabs were used. One-way analysis of variance (ANOVA) and Tukey (5%) were used for the DH data. The four groups of components (UC 4.1, UC 3.6, AC 4.1, AC 3.6 ) were prepared according to the ISO 14801: 2007 standard and submitted to 1,000,000 cycles, with a load of 100 N and frequency of 1 Hz in a universal fatigue testing machine. Results indicated conformity of adaptation (FV) among components varying from 70% to 90%. Concerning DH, the two groups of switching components (UC 3.6 and AC 3.6) presented a negative gap of 7.07% and 5.36% respectively in relation to the regular platform, while the RP groups (UC 4.1 and AC 4.1) presented a negative gap of 1.21% and 0% (p?0.05). The loss of torque after the cycling test were: 25% (UC 4.1), 39% (UC 3.6), 38% (AC 4.1) and 51% (AC 3.6), (p? 0.01). Hence, the result of the present study indicate that the switching platform components present a favorable short-term biological behavior according to the literature, but limited biomechanical behavior. In adaptation factor, there is a strong degree of precision in almost all samples in terms of FV. DH is noticed in all groups. It is also noticeable that in the platform switching groups the loss of torque after mechanical cycling test was larger. / O estudo objetivou analisar a conformidade de adapta??o de componentes prot?ticos de padr?o switching e o comportamento dos mesmos frente a teste mec?nico de fadiga, dispostos em dois manuscritos de acordo com a norma e perfil de publica??o de duas revistas espec?ficas da ?rea de reabilita??o oral. No manuscrito 1 foi realizada uma revis?o liter?ria, que elucidou conceitos relacionados ? utiliza??o da filosofia switching e seus benef?cios biol?gicos evidenciados pela literatura. No entanto, fatores relacionados com estabilidade biomec?nica associados a esse novo conceito demonstraram-se constituir uma tem?tica pouco explorada e evidenciada pela ci?ncia, necessitando, serem melhor compreendidos e confirmados por estudos que avaliem quest?es biomec?nicas sobre esta filosofia. Atrav?s dessa car?ncia demonstrada pela revis?o liter?ria, passou-se a etapa de estudo laboratorial, objetivando buscar respostas a quest?es envolvendo a estabilidade prot?tica de longo prazo. O manuscrito 2 avaliou a conformidade de adapta??o de componentes switching e seu comportamento frente a testes de ciclagem mec?nica, tendo como metodologia o uso de 40 componentes prot?ticos para reabilita??es unit?rias sobre implantes padr?o Hex?gono Externo 4,1 Plataforma Regular, sendo divididos em quatro grupos: 10 componentes UCLA de 4,1 mm (grupo UC 4,1), 10 componentes UCLA de 3,6 mm (grupo UC 3,6) , 10 componentes tipo pilares c?nicos de 4,1 mm (grupo AC 4,1) e 10 pilares c?nicos de 3,6 mm (grupo AC 3,6) sobre referido implante padr?o RP Hex?gono Externo 4,1 mm. Os grupos foram avaliados por Espectroscopia de Energia Dispersiva (EDS) para confirmar o padr?o de manufatura das amostras, e tamb?m comparada a adapta??o com aux?lio de Microscopia Eletr?nica de Varredura (MEV) quanto a Fenda Vertical (FV) e Discrep?ncia Horizontal (DH). Para a an?lise estat?stica dos dados de FV, aplicou-se os testes de Kruskal-wallis e Crosstabs, e para DH o procedimento de an?lise de Vari?ncia (Anova-Oneway) e de Tukey, ao n?vel de signific?ncia de 5%. Os quatro grupos de componentes (UC 4,1, UC 3,6, AC 4,1, AC 3,6 ) foram preparados conforme norma ISO 14801: 2007 e submetidos ? 1.000.000 de ciclos, com carga de 100 N e frequ?ncia de 1 Hz em m?quina de simula??o de fadiga. Resultados indicaram conformidade de adapta??o de fenda entre componentes variando de 70% a 90%. Quanto ? DH os dois grupos com componentes Switching (UC 3,6 e AC 3,6) apresentaram degrau negativo de 7,07 % e 5,36% respectivamente em rela??o a plataforma regular, enquanto os grupos de padr?o regular (UC 4,1 e AC 4,1) degrau negativo de 1,21% e 0 % (p?0,05). Em rela??o ? perda de torque ap?s a ciclagem foram obtidos os graus percentuais em cada grupo de 25% (UC 4,1), 39% (UC 3,6), 38% (AC 4,1) e 51% (AC 3,6), (p? 0,01). Desse modo, resultados do presente estudo indicam que os componentes com padr?o switching apresentam-se com comportamento biol?gico favor?vel de curto prazo de acordo com a literatura consultada, mas comportamento biomec?nico limitado. Em fator de adapta??o h? um grau de marcante precis?o em quase todas as amostras em termos de FV. A DH ? notada em maior ou menor grau, tanto em amostras regulares, quanto em padr?o switching. Observou-se que quanto maior o degrau negativo de discrep?ncia horizontal, maior ? o grau de perda de torque ap?s a ciclagem mec?nica. Foi observada tamb?m uma tend?ncia de que quanto mais marcada a aplica??o do conceito switching, maior a perda de torque associada.
5

O funk e a leitura dial?gica de sujeitos na perspectiva bakhtiniana da linguagem

Silva, Manuella Queiroz da 29 March 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-11-06T21:09:53Z No. of bitstreams: 1 ManuellaQueirozDaSilva_DISSERT.pdf: 3438439 bytes, checksum: ea831553438a91b03d4fa9677e4112ed (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-11-20T23:07:16Z (GMT) No. of bitstreams: 1 ManuellaQueirozDaSilva_DISSERT.pdf: 3438439 bytes, checksum: ea831553438a91b03d4fa9677e4112ed (MD5) / Made available in DSpace on 2017-11-20T23:07:16Z (GMT). No. of bitstreams: 1 ManuellaQueirozDaSilva_DISSERT.pdf: 3438439 bytes, checksum: ea831553438a91b03d4fa9677e4112ed (MD5) Previous issue date: 2017-03-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O presente trabalho, que envolve os alunos do 9? ano do Ensino Fundamental, prop?e uma busca do (re)conhecimento do sujeito social representado nas letras do funk que s?o utilizadas como instrumentos para a reflex?o no ambiente escolar. O estudo em quest?o tem como aporte te?rico Mikhail Bakhtin (2011), juntamente com as discuss?es que envolvem o conhecido C?rculo de Bakhtin. Partindo das leituras feitas e por meio das atividades constantes do prot?tipo de ensino, a discuss?o na turma, nas rodas de conversa, aborda o sujeito social encontrado nas letras das m?sicas do g?nero discursivo funk. Entendendo que a dialogicidade discursiva tamb?m se perfaz no ato da leitura, este estudo procura compreender o enunciado concreto, permeado pelo g?nero discursivo literomusical funk, na tentativa de (re)conhecer as vozes existentes, bem como de onde v?m essas vozes, que valores as representam e se elas se comunicam e se identificam com as vozes dos alunos envolvidos na pesquisa. O trabalho tamb?m toma por base as formula??es feitas por Rojo (2015) sobre prot?tipos de ensino, bem como estudos sobre a leitura em sala de aula, segundo Geraldi (1997). O produto dos estudos realizados originou um prot?tipo de ensino usando o g?nero funk. Nesse sentido, os alunos produziram textos que envolvem a reflex?o sobre o g?nero discursivo funk. Com isso, tomaram posi??o ativa frente ?s quest?es das letras de m?sica trabalhadas em sala de aula. Esta pesquisa procura contribuir para a forma??o de leitores cr?ticos e responsivos, capazes de usar a linguagem em qualquer situa??o comunicativa e, antes de tudo, cidad?os conscientes e minimamente proficientes na leitura. / In the search of the underlying message of the social subject represented on funk music lyriccs and their use as an analytical instrument whthin the academic environment, we have performed this study with students of the 9th Grade of Primary Education. The study takes into consideration the theoretical contribution of Mikhail Bakhtin (2011), and discussions that ensued within the Bakhtin Circle. Starting from a class reading of funk music lyrics, the participants extensively discussed the social subject found in this discursive genre through different teaching prototype activities. Considering that the discursive dialogue is also present in the act of reading, our goal is to understanding the core message embedded within the literomusical funk genre, in an attempt to identify the existing voices, as well as to understand where those voices come from, which values they represent and whether they communicate and relate to the voices of the study participants. Our work is also inspired by the studies conducted by Roxane Rojo (2015) through teaching prototypes recommended by her, and by studies concerning reading in the classroom by Geraldi (1997). As a result, we have established through this study a teaching prototype using the funk music genre as background. The students have written essays about the discursive genre funk in which they have actively positioned themselves about topics present in the lyrics analyzed in classroom. This study seeks to contribute to the formative process of minimally proficient readers, those capable of using language in any communicative format and, ultimately, to transform these readers in critical, responsive, and conscious citizens.
6

Caracteriza??o da interface entre cilindros de pilares de implante e ligas fundidas de Co-Cr com diferentes t?cnicas de fundi??o

Rodrigues Neto, Dimas Jo?o 19 January 2017 (has links)
Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-06-26T14:53:16Z No. of bitstreams: 1 TES_DIMAS_JOAO_RODRIGUES_NETO_PARCIAL.pdf: 405454 bytes, checksum: d48967a61777e3e773d5a2112997ee13 (MD5) / Made available in DSpace on 2017-06-26T14:53:16Z (GMT). No. of bitstreams: 1 TES_DIMAS_JOAO_RODRIGUES_NETO_PARCIAL.pdf: 405454 bytes, checksum: d48967a61777e3e773d5a2112997ee13 (MD5) Previous issue date: 2017-01-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / For a satisfactory clinical performance, pre-fabricated Co-Cr cylinders must have metallurgical compatibility to Co-Cr based cast alloys. A uniform interface with adequate union and resistance, with absence of interfacial reaction and porosities must be obtained. The present in vitro study aimed to evaluate the metallurgical compatibility at the interface between pre-fabricated Co-Cr cylinders and alloys for Co-Cr compound casting applying different casting techniques. In manuscript 2 the metallurgical compatibility and the interface between implant and alloy cylinders were evaluated for Co-Cr casting with different melting temperatures. Methodology: Three pre-fabricated Co-Cr prosthetic implant cylinders (Neodent, Pi-Br?nemark, Dentium) were subjected to casting with Co-Cr alloy using different casting techniques (Flame Torch, Induction / Centrifugation, Induction / Vacuum). Optical microscopy and Scanning Electron Microscopy (SEM) were used to characterize the obtained microstructures. The elementary composition of the cylinders and diffusion characteristics in the interfacial region between molten alloy and cylinder were determined by dispersive energy spectroscopy (EDS). Vickers microhardness was measured at interface, cylinder and cast alloy. The ANOVA and Tukey test were used to evaluate microhardness values. In the manuscript 2 cylinders based on Co-Cr were overfused with alloys with different melting temperatures and all microstructural analysis and microhardness tests were performed. Results: In the manuscript 1 a union between pre-fabricated cylinders and Co-Cr based alloys was observed microstructurally. An ideal interface was obtained with absence of interfacial reaction or significant porosities with the casting with the induction techniques (centrifugation and vacuum), but excess of porosities and failures were observed with the Torch casting technique. In manuscript 2 a microstructural bond was observed between the alloys and the cylinder, evidencing that both high melt alloy and low melt alloy presented compatibility with the Co-Cr cylinder. Microhardness values, both in manuscript 1 and in manuscript 2 also proved to form a satisfactory interface. Conclusions: It was concluded from manuscript 1 and 2 that both high and low melt temperature Co-Cr have metallurgical compatibility to pre-fabricated Co-Cr cylinders, showing an ideal interface. However, the technique of casting applied is relevant, and the torch technique has been shown to be less indicated due to the lack of standardization of the obtained results. / Para um bom desempenho clinico, cilindros de pilares pr? fabricados de Co-Cr devem apresentar compatibilidade metal?rgica a ligas de sobrefundi??o a base de Co-Cr. Uma interface uniforme com adequada uni?o e resist?ncia, com aus?ncia de rea??o interfacial e porosidades devem ser obtidas. O presente estudo, in vitro, objetivou atrav?s do manuscrito 1 avaliar a compatibilidade metal?rgica na interface entre cilindros pr? fabricados de Co-Cr e ligas para sobrefundi??o de Co-Cr com diferentes t?cnicas de fundi??o. No manuscrito 2, foi avaliado a compatibilidade metal?rgica e a interface entre cilindro de implante e ligas para sobrefundi??o de Co-Cr com diferentes temperaturas de fus?o. Metodologia: Tr?s cilindros pr?-fabricados para pr?tese sobre implantes em Co-Cr (Neodent, Pi-Br?nemark, Dentium) foram sorefundidos com liga de Co-Cr com diferentes t?cnicas de fundi??o (Ma?arico, Indu??o/centrifuga??o, Indu??o/v?cuo). Microscopia ?ptica e Microscopia eletr?nica de varredura (MEV) foram usadas para caracteriza??o das microestruturas. A composi??o elemental dos cilindros e caracter?sticas de difus?o na regi?o interfacial entre liga fundida e cilindro foram determinadas atrav?s de espectroscopia por energia dispersiva (EDS). Microdureza de Vickers foi aplicada na interface, cilindro e liga fundida. Foi aplicado o teste de ANOVA e Tukey para avalia??o dos valores microdureza. No manuscrito 2, cilindros a base de Co-Cr foram sobrefundidos com ligas com diferentes temperaturas de fus?o e foi realizada toda analise microestrutural e testes de microdureza. Resultados: No manuscrito 1 observou-se microestruturalmente uma uni?o entre cilindros pr? fabricados e ligas a base de Co-Cr. Foi obtida uma interface ideal com aus?ncia de rea??o interfacial ou porosidades significantes com a fundi??o com as t?cnicas por indu??o (centrifuga??o e v?cuo), por?m excesso de porosidades e falhas foram observados com a t?cnica de fundi??o ? ma?arico. No manuscrito 2 observou-se uma uni?o microestrutural entre as ligas e o cilindro avaliado, evidenciando que tanto liga de alta fus?o, quanto de baixa fus?o apresentam compatibilidade ao cilindro de Co-Cr. Valores de microdureza, tanto no manuscrito 1 como no manuscrito 2 tamb?m comprovaram a forma??o de uma interface satisfat?ria. Conclus?es: Concluiu-se atrav?s do manuscrito 1 e 2 que ligas de alta e baixa temperatura de fus?o a base de Co-Cr apresentam compatibilidade metalurgica a cilindros pr? fabricados de Co-Cr apresentando uma interface ideal. Por?m, a t?cnica de fundi??o aplicada ? relevante, sendo que a t?cnica ? ma?arico se mostra a menos indicada devido a falta de padroniza??o dos resultados obtidos.
7

Aplica??o da astronomia ao ensino de f?sica e biologia

Dos Santos, Iran?ia Campos 18 December 2017 (has links)
Submitted by Verena Pereira (verenagoncalves@uefs.br) on 2018-07-16T21:58:45Z No. of bitstreams: 1 DISSERTA??O FINAL 2018 - I_Iraneia.pdf: 8376499 bytes, checksum: 3d565609f591304bfbc372d0f241281c (MD5) / Made available in DSpace on 2018-07-16T21:58:45Z (GMT). No. of bitstreams: 1 DISSERTA??O FINAL 2018 - I_Iraneia.pdf: 8376499 bytes, checksum: 3d565609f591304bfbc372d0f241281c (MD5) Previous issue date: 2017-12-18 / Recognizing the importance of the insertion of Astronomy in our daily life, this dissertation has as main characteristic, to promote a holistic and interdisciplinary learning to the contents of Physics and Biology in classes of 1st and 2nd year of the High School of the Lu?s Eduardo Magalh?es Model School in Feira de Santana. The problems related to the problems and difficulties in teaching science in high school are noted through reports cited in IDEB and PISA Research Against the background of the recommendations of the PCN +, supported by a STEM approach, support the proposal of this work, aimed at the development of activities promoting Science Teaching, anchored in technological and astronomical themes. Concerned with the legitimacy of distinguishing skills through the students' cognitive levels, the Marzano and SOLO Taxonomies were used for a hierarchical organization of cognitively organized learning objectives Following a contextualization of this theme, the activities were organized in structured tests of interest in the Research (ROSE); research and in-house study on relevant scientific topics in Astronomy and its related fields; survey of interdisciplinary issues related to Astronomy and Natural Sciences and their Technologies; development of support material structured in the form of Didactic Sequences; development of the Ares Project and culminating in the holding of the Science Fair; and creation of the interactive page on Facebook to publicize events and activities. As a result of more than two years of project development, statistical analyzes were performed for the validation of quantitative results, while a qualitative analysis is used for evaluations of cognitive taxonomic development. Both evaluations significantly showed that the project interventions produced a qualitatively and quantitatively relevant transformation in the learning and cognitive understanding process of the students, showing the relevance of the incorporation of contextualized S & T topics as motivating elements in the learning process / Reconhecendo a import?ncia da inser??o da Astronomia em nosso cotidiano, esta disserta??o tem como principal caracter?stica, promover uma aprendizagem hol?stica e interdisciplinar aos conte?dos de F?sica e Biologia em turmas de 1? e 2? anos do Ensino M?dio do Col?gio Modelo Lu?s Eduardo Magalh?es em Feira de Santana. A problem?tica relacionada ao problemas e dificuldades no ensino de Ci?ncias no Ensino M?dio s?o notadas atrav?s de relatos citados nas Pesquisas IDEB e PISA. Tendo como pano de fundo as recomenda??es dos PCN+, suportada por uma abordagem com metodologia STEM, suportam a proposta deste trabalho, destinado ao desenvolvimento de atividades promotoras do Ensino de Ci?ncias, ancoradas em temas tecnol?gicos e astron?micos. Preocupada com a legitimidade de distinguir habilidades atrav?s dos n?veis cognitivos dos estudantes foram empregadas as Taxonomias Marzano e SOLO para uma organiza??o hier?rquica dos objetivos de aprendizagem organizados cognitivamente. Seguindo uma contextualiza??o dessa tem?tica, as atividades foram organizadas em testes de interesse estruturados na Pesquisa (ROSE); pesquisa e estudo em sala sobre temas cient?ficos relevantes de Astronomia e suas ?reas afins; levantamento de quest?es interdisciplinares relacionado ? Astronomia e as Ci?ncias da Natureza e suas Tecnologias; desenvolvimento de material de suporte estruturados na forma de Sequ?ncias Did?ticas; desenvolvimento do Projeto Ares e culminando com a realiza??o de Feira de Ci?ncias; e cria??o da p?gina interativa no Facebook para divulga??o de eventos e atividades. Como resultados decorrentes dos mais de dois anos de desenvolvimento do projeto foram realizadas an?lises estat?sticas para a valida??o dos resultados quantitativos, enquanto que uma an?lise qualitativa ? usada para as avalia??es de desenvolvimento cognitivo taxon?mico. Ambas as avalia??es constataram significantemente que as interven??es do projeto produziram uma transforma??o relevante quali e quantitativamente no processo de aprendizagem e de compreens?o cognitiva dos estudantes, mostrando a relev?ncia da incorpora??o de tem?ticas contextualizadas em C&T como elementos motivadores no processo de aprendizagem
8

��tude du r��le de la prot��ine kinase LegK2 dans la virulence de Legionella pneumophila

Hervet, ��va 14 October 2011 (has links) (PDF)
Legionella pneumophila est la bact��rie responsable de la l��gionellose, une pneumonie atypique dans les pays industrialis��s. Les souches pathog��nes sont issues de notre environnement apr��s multiplication �� l'int��rieur d'amibes, sont diss��min��es par la technologie humaine, puis peuvent infecter les macrophages alv��olaires humains. Ce travail vise �� caract��riser une famille d'effecteurs du syst��me de s��cr��tion de type IV Dot/Icm transloqu��s dans le cytoplasme de la cellule h��te, des prot��ine kinases, et en particulier �� ��tablir le r��le de la prot��ine kinase LegK2 dans la virulence. L'analyse in silico et des tests de phosphorylation in vitro ont permis d'identifier 5 prot��ine kinases fonctionnelles, LegK1-LegK5, cod��es par la souche ��pid��mique L. pneumophila Lens. Des tests de translocation ont montr�� qu'�� l'exception de LegK5, les prot��ine kinases de Legionella sont transloqu��es dans la cellule h��te de fa��on Icm/Dot d��pendante. LegK2 joue un r��le cl�� dans la virulence, comme d��montr�� par inactivation de g��ne. Les vacuoles contenant le mutant legK2 pr��sentent un recrutement moins efficace de reticulum endoplasmique, ce qui entraine une r��plication intracellulaire retard��e. Un mutant de substitution d��ficient pour l'activit�� kinase pr��sente les m��mes d��fauts de virulence, ce qui d��montre le r��le central de la phosphorylation dans le contr��le de ce processus. Les m��canismes mol��culaires contr��l��s par LegK2 sont actuellement recherch��s par identification de partenaires et/ou substrats prot��iques.
9

Mod??lisation d'un syst??me de lib??ration d'un peptide d??riv?? de la BMP-9 et ??tude m??canistique comparative entre la BMP-9 et la BMP-2

Lauzon, Marc-Antoine January 2014 (has links)
Le vieillissement croissant de la population canadienne aura une incidence, dans les ann??es ?? venir, sur les risques de fractures ost??oporotiques et autres pathologies de l'os. Parmi ces risques, les fractures avec pertes osseuses pr??sentent des d??fis consid??rables et causent un lourd fardeau ??conomique. La soci??t?? Ost??oporose Canada estime que plus de 30 milliards de dollars seront d??pens??s pour le traitement de l???ost??oporose et de leurs fractures associ??es d???ici 2018. La m??thode de comblement des pertes osseuses standard actuelle, soit l'autogreffe, est limit??e et pr??sente des risques pour le patient. ?? titre d'alternative, deux strat??gies ont ??t?? jusqu'?? maintenant ??tudi??es: les syst??mes de lib??ration de facteurs de croissance (?? growth factor delivery systems ??, GFDS) et le d??veloppement de mat??riaux biomim??tiques. Ces deux strat??gies ont comme point commun l'utilisation de facteurs de croissance ost??og??niques comme les prot??ines morphog??n??tiques osseuses (BMPs), telles la BMP-2 (r??f??rence commerciale) et la BMP-9. Malgr?? leur effet important, les BMPs restent couteuses ?? produire. Le laboratoire de N. Faucheux a d??velopp?? un peptide (pBMP-9) d??riv?? de la BMP-9 qui poss??de un effet ost??og??nique d??montr??, mais dont les m??canismes d???action et le comportement en syst??me de lib??ration restent ?? ??tre ??tudi??s. Les objectifs de ce projet de recherche ont donc port?? sur l?????tude du comportement de cellules osseuses pr??ost??oblastes murins (MC3T3-E1) face ?? ces facteurs de croissance ainsi que sur le suivi et la mod??lisation des cin??tiques de lib??ration du pBMP-9 ?? partir d???une matrice de collag??ne, utilis??e actuellement en clinique. Le m??moire poss??de ainsi trois volets. Le premier volet de ces travaux a consist?? ?? faire une revue de la litt??rature sur le processus de r??g??n??ration osseuse endochondrale afin de bien comprendre le r??le jou?? par les facteurs de croissance et cerner les d??fis de conception d???un GFDS utilis?? en r??g??n??ration osseuse. Les nouvelles approches de GFDS ont ??t?? revues en d??tail ainsi que les principaux mod??les math??matiques d??velopp??s et appliqu??s aux mol??cules th??rapeutiques. Cette revue de la litt??rature a ??t?? publi??e dans Journal of Controlled Release. Le second volet de ces travaux s???est pench?? sur l?????tude et la mod??lisation math??matique des cin??tiques de lib??ration du pBMP-9 ?? partir d???hydrogels de collag??ne. Les r??sultats exp??rimentaux ont men?? ?? la r??daction d???un article qui vient d?????tre accept?? dans la revue Journal of Controlled Release. Cette ??tude consistait ?? ??valuer les m??canismes de transfert de masse impliqu??s dans la lib??ration pour diff??rentes concentrations de pBMP-9 ?? partir d'hydrogels de collag??ne. Les cin??tiques de lib??ration ont ??t?? mod??lis??es et ont montr?? la pr??sence d'interactions importantes entre le pBMP-9 et les fibres de collag??ne. Le troisi??me volet a consist?? ?? d??terminer l'effet dose de la BMP-9 et de la BMP-2 sur la capacit?? des MC3T3-E1 ?? se diff??rencier en pr??sence ou en absence de s??rum de veau foetal (?? foetal bovine serum ??, FBS). Ces travaux ont conduit ?? la r??daction d???un article qui vient d?????tre accept?? dans la revue Tissue Engineering Part A. La BMP-9 ??tant jusqu'alors mal comprise, l'??tude s'est pench??e sur cette prot??ine tout en ayant comme objectif de transposer les connaissances au pBMP-9. Les r??sultats ont d??montr?? que les m??canismes d'action de la BMP-9 ??taient tr??s diff??rents de ceux de la BMP-2 en pr??sence de FBS. Les r??sultats ont ??galement permis d'??tablir que, ?? l'instar de la BMP-2, la pr??sence de FBS potentialise fortement l'effet ost??og??nique de la BMP-9. Cet effet a d???ailleurs pu ??tre r??cr???? par l???IGF-2. Les conclusions de ce travail favoriseront le d??veloppement de syst??mes de lib??ration ost??og??niques plus efficaces.
10

Mod??lisation d'un syst??me de lib??ration d'un peptide d??riv?? de la BMP-9 et ??tude m??canistique comparative entre la BMP-9 et la BMP-2

Lauzon, Marc-Antoine January 2014 (has links)
Le vieillissement croissant de la population canadienne aura une incidence, dans les ann??es ?? venir, sur les risques de fractures ost??oporotiques et autres pathologies de l'os. Parmi ces risques, les fractures avec pertes osseuses pr??sentent des d??fis consid??rables et causent un lourd fardeau ??conomique. La soci??t?? Ost??oporose Canada estime que plus de 30 milliards de dollars seront d??pens??s pour le traitement de l???ost??oporose et de leurs fractures associ??es d???ici 2018. La m??thode de comblement des pertes osseuses standard actuelle, soit l'autogreffe, est limit??e et pr??sente des risques pour le patient. ?? titre d'alternative, deux strat??gies ont ??t?? jusqu'?? maintenant ??tudi??es: les syst??mes de lib??ration de facteurs de croissance (?? growth factor delivery systems ??, GFDS) et le d??veloppement de mat??riaux biomim??tiques. Ces deux strat??gies ont comme point commun l'utilisation de facteurs de croissance ost??og??niques comme les prot??ines morphog??n??tiques osseuses (BMPs), telles la BMP-2 (r??f??rence commerciale) et la BMP-9. Malgr?? leur effet important, les BMPs restent couteuses ?? produire. Le laboratoire de N. Faucheux a d??velopp?? un peptide (pBMP-9) d??riv?? de la BMP-9 qui poss??de un effet ost??og??nique d??montr??, mais dont les m??canismes d???action et le comportement en syst??me de lib??ration restent ?? ??tre ??tudi??s. Les objectifs de ce projet de recherche ont donc port?? sur l?????tude du comportement de cellules osseuses pr??ost??oblastes murins (MC3T3-E1) face ?? ces facteurs de croissance ainsi que sur le suivi et la mod??lisation des cin??tiques de lib??ration du pBMP-9 ?? partir d???une matrice de collag??ne, utilis??e actuellement en clinique. Le m??moire poss??de ainsi trois volets. Le premier volet de ces travaux a consist?? ?? faire une revue de la litt??rature sur le processus de r??g??n??ration osseuse endochondrale afin de bien comprendre le r??le jou?? par les facteurs de croissance et cerner les d??fis de conception d???un GFDS utilis?? en r??g??n??ration osseuse. Les nouvelles approches de GFDS ont ??t?? revues en d??tail ainsi que les principaux mod??les math??matiques d??velopp??s et appliqu??s aux mol??cules th??rapeutiques. Cette revue de la litt??rature a ??t?? publi??e dans Journal of Controlled Release. Le second volet de ces travaux s???est pench?? sur l?????tude et la mod??lisation math??matique des cin??tiques de lib??ration du pBMP-9 ?? partir d???hydrogels de collag??ne. Les r??sultats exp??rimentaux ont men?? ?? la r??daction d???un article qui vient d?????tre accept?? dans la revue Journal of Controlled Release. Cette ??tude consistait ?? ??valuer les m??canismes de transfert de masse impliqu??s dans la lib??ration pour diff??rentes concentrations de pBMP-9 ?? partir d'hydrogels de collag??ne. Les cin??tiques de lib??ration ont ??t?? mod??lis??es et ont montr?? la pr??sence d'interactions importantes entre le pBMP-9 et les fibres de collag??ne. Le troisi??me volet a consist?? ?? d??terminer l'effet dose de la BMP-9 et de la BMP-2 sur la capacit?? des MC3T3-E1 ?? se diff??rencier en pr??sence ou en absence de s??rum de veau foetal (?? foetal bovine serum ??, FBS). Ces travaux ont conduit ?? la r??daction d???un article qui vient d?????tre accept?? dans la revue Tissue Engineering Part A. La BMP-9 ??tant jusqu'alors mal comprise, l'??tude s'est pench??e sur cette prot??ine tout en ayant comme objectif de transposer les connaissances au pBMP-9. Les r??sultats ont d??montr?? que les m??canismes d'action de la BMP-9 ??taient tr??s diff??rents de ceux de la BMP-2 en pr??sence de FBS. Les r??sultats ont ??galement permis d'??tablir que, ?? l'instar de la BMP-2, la pr??sence de FBS potentialise fortement l'effet ost??og??nique de la BMP-9. Cet effet a d???ailleurs pu ??tre r??cr???? par l???IGF-2. Les conclusions de ce travail favoriseront le d??veloppement de syst??mes de lib??ration ost??og??niques plus efficaces.

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