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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.
1071

A??o de polissacar?deos sulfatados de Fucus Vesiculosus na Hemostasia e no sistema complemento

Azevedo, Tarciana Carvalho Gurgel de 18 July 2006 (has links)
Made available in DSpace on 2014-12-17T14:03:41Z (GMT). No. of bitstreams: 1 TarcianaCGA.pdf: 634423 bytes, checksum: 54bd90fdc2abea42aaa8c6e698915963 (MD5) Previous issue date: 2006-07-18 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Fucans are a family of sulfated homo and teropolysaccharides respectively, composed mainly of a- (1?2) and a- (1?3) linked by L-fucose residues. Properties such as the ability to act as an anti-contraceptive, to reduce cholesterol levels, and to act as an anti-tumor agent are much related. We have focused our attention on the anticoagulant properties, platelet aggregation, hemorrhagic activity and complement system in vitro of commercial fucoidan (F) and their purified fractions (F1, F2 and F3) from Fucus vesiculosus obtained from fractionation of the fucoidan with different concentrations of acetone 1, 2 and 3v. These compounds were chemically characterized and the fucoidan (F) was modified by desulfation. The anticoagulant activity of the compounds was assessment by activated partial thromboplastin time (APTT) and prothrombine time assay (PT) using citrated normal human plasma. The results of APPT test showed that F, F1 and F2 have high anticoagulants activities 240.0 s (5 ?g). The F3 showed 73.7 s in the same concentrations. The results obtained with PT test to F, F1, F2 and F3 were 81.5 s, 120.0 s, 57.1 and 32.5 s respectively with 50 ?g. The dessulfated polymer showed a decrease in the anticoagulant activity in these two tests. Platelet aggregation assay was measured turbidimetrically with platelet aggregometer by method of Born. The aggregation platelet with F and fractions F1, F2 and F3 exhibited a two-phase answer in the concentration of 5 mg/mL with maximum aggregation of 76.36 ? 10.3% ; 69.54 ? 9.40%; 75.94 ? 9.01%; 51.13 ? 9.59% respectively. However, was observed a hipoaggregate profile F (15.17 ? 5.2%), F1 (7.40 ? 3.04 %), F2 (19.1 ? 5.41%) and F3 (5.09 ? 3.02%) at 0.1 mg/mL. The hemorrhagic activity assay was carried in Wistar rats and showed that these compounds have low hemorrhagic effect when compared to heparin. The complement system ( alternative pathway was made using non-sensibilized rabbit red blood cells The results of complement system essay showed that F , F2 and F3 have action inhibitory in relation to the group control 0.544, 0.697, 0.622 and 0.958 respectively The results showed that these compounds have action on this system. Interaction of the polisaccharides with proteins C3 and C4 showed that the fraction F1 stimulated the activity assay hemolytic using red blood cells / Fucanas s?o uma fam?lia de homo e hetero polissacar?deos sulfatados, formadas por uma cadeia central com liga??es α-(1→2) ou α-(1→3) unidas atrav?s de res?duos de L-fucose. Propriedades como a habilidade para agir como um anticoncepcional, reduzir n?veis de colesterol, e agir como um agente anti-tumoral foram relatadas. N?s focalizamos nossa aten??o nas propriedades anticoagulantes, agrega??o plaquet?ria, atividade anti-hemost?tica e sistema de complemento in vitro do fucoidan comercial e das fra??es F1, F2 e F3 de Fucus vesiculosus obtidas atrav?s do fracionamento do fucoidan por precipta??o com acetona (1, 2 e 3v). A atividade anticoagulante dos compostos foi avaliada pelo tempo de tromboplastina parcial ativado (APTT) e o tempo de protrombina (PT) usando plasma humano citratado. Os resultados do teste de APPT mostraram que o Fucoidan (F) e as fra??es F1 e F2 t?m altas atividades anticoagulantes 240,0 s (5 ?g), enquanto que a F3 mostrou 73,7s nas mesma concentra??o. Os resultados obtidos com PT para o F, F1, F2 e F3 foram 81,5 s, 120,0 s, 57,1 e 32,5 s respectivamente usando a massa de 50 ?g. A dessulfata??o do Fucoidan demonstrou uma diminui??o da atividade anticoagulante nos dois testes. O ensaio de agrega??o plaquet?ria foi realizado no agregometro de acordo com o m?todo de Born. A agrega??o plaquet?ria induzida pelo fucoidam e pelas fra??es de F1, F2 e F3 exibiram uma resposta bif?sica na concentra??o de 5 mg/mL com amplitude m?xima de agrega??o de 76,36% ? 10,3%; 69,54% ? 9,40%; 75,94% ? 9,01%; 51,13% ? 9,59% respectivamente. Por?m, na concentra??o 0,1 mg/mL foi observada um perfil hipoagregante para o Fucoidan (15,17% ? 5,2) e para as fra??es F1 (7,4% ? 3,04%), F2 (19,1% ? 5,41) e F3 (5,09% ? 3,02%). A atividade anti-hemost?tica foi realizada com ratos machos da linhagem Wistar e demonstrou que estes compostos t?m efeito hemorr?gico residual menor do que o da heparina. A a??o dos polissacar?deos fucosilados sulfatados na via alternativa do sistema complemento foi realizada atrav?s da utiliza??o de eritr?citos de coelhos n?o sensibilizados. Os resultados para o Sistema Complemento mostraram que o F, F2 e F3 t?m a??o neste sistema, apresentando efeito inibit?rio em rela??o ao grupo controle 0,544, 0,697, 0,622 e 0,958 respectivamente. Intera??es dos polissacar?deos com as prote?nas C3 e C4 demonstraram que a fra??o F1 estimula a atividade hemol?tica do complemento usando eritr?citos de coelho. Conclu?mos que estes a??cares t?m atividade anticoagulante e atuam como inibidores do sistema complemento sendo uma valiosa droga que pode ser empregada em doen?as relacionadas com inflama??o e coagula??o sang??nea
1072

Agrega??o familiar e resultados maternos e perinatais da pr?-ecl?mpsia severa em popula??o do Rio Grande do Norte

Bezerra, Patr?cia Costa Fonseca Meirelles 28 November 2007 (has links)
Made available in DSpace on 2014-12-17T14:13:21Z (GMT). No. of bitstreams: 1 PatriciaCFMB.pdf: 373126 bytes, checksum: 359c5249b6f868d7e2bf1418acaf9bec (MD5) Previous issue date: 2007-11-28 / To determine whether there is familiar aggregation of severe preeclampsia in a Brazilian population from Rio Grande do Norte and to characterize the maternal and perinatal outcomes in the studied population. Methods: A case control study was performed with 412 participants who were admitted at Maternidade Escola Janu?rio Cicco (MEJC) for medical care. Of these, 264 subjects presented normal blood pressure and 148 were cases. Cases were composed of eclampsia (n=47), HELLP Syndrome (n=85) and Eclampsia associated with HELLP syndrome (n=16). The diagnosis of these illness were based on the citeria developed by National High Blood Pressure Education Program Working (2000). An interview was performed with each subject and questions related to personal and familiar history of hypertension, preeclampsia, HELLP syndrome and eclampsia. Statistical analysis was performed and comparison of median and mean between cases and controls were performed, with the level of significance of 5%. The Odds-Ratio was determined to estimate the risk of preeclampsia within the families. Results: There were no difference in the demographic data between cases and controls. Previous history of chronic hypertension and preeclampsia was more frequent in the case group. Headaches were more frequent in eclampsia and epigastric pain in the HELLP syndrome cases. Bleeding and oliguria were more frequently found in the eclampsia associated with HELLP syndrome cases. Acute Renal insufficiency was a common complication in the case group, but these cases did not evolve to chronic renal insufficiency. The maternal mortality was 0.4% and the perinatal mortality was high, 223 per 1,000 live births. The 111 risk of a woman to develop preeclampsia whose mother has hypertension or had preeclampsia was respectively 2.5 and 3.5. This risk was increased 5 times, when a sibling has hypertension and 6 times when both sibling and mother had previous history of preeclampsia. Conclusions: This study confirms that there is familiar aggregation of preeclampsia in this Brazilian population. The potential for cardiovascular complications due to development of chronic hypertension indicates the need of closely follow up of women who develop preeclampsia / Determinar a agrega??o familiar na pr?-ecl?mpsia severa em popula??o brasileira do Rio Grande do Norte e caracterizar os resultados maternos e perinatais desta popula??o. M?todos: Estudo de caso controle, no qual foram arroladas 412 pacientes internadas na Maternidade Escola Janu?rio Cicco (MEJC). Dessas, 264 pacientes normotensas, grupo controle, e 148 com pr?-ecl?mpsia severa, grupo dos casos. Os casos foram compostos por ecl?mpsia (n=47), s?ndrome HELLP (n=85) e por ambas, ecl?mpsia e s?ndrome HELLP (n=16). O diagn?stico, destas doen?as, foram baseados nos crit?rios adotados pelo National High Blood Pressure Education Program Working (2000). Foi realizado inqu?rito familiar quanto ? agrega??o familiar, sendo questionadas informa??es a respeito de antecedentes de hipertens?o cr?nica, pr?-ecl?mpsia, ecl?mpsia e s?ndrome HELLP. An?lise estat?stica foi realizada para avaliar associa??es e correla??es entre vari?veis, bem como compara??o de m?dias ou medianas, adotando-se um n?vel de signific?ncia de 5%. O Odds-Ratio foi calculado para estimar o risco da pr?-ecl?mpsia severa nas fam?lias. Resultados: N?o houve diferen?a nos par?metros demogr?ficos entre casos e controles. A hist?ria pr?via de hipertens?o cr?nica e pr?-ecl?mpsia foram mais frequentes nas pacientes com pr?-ecl?mpsia severa. A cefal?ia foi o sintoma mais freq?ente na ecl?mpsia e a epigastralgia na s?ndrome HELLP. A hemorragia e a olig?ria foram mais presentes quando associado ecl?mpsia e s?ndrome HELLP. A insufici?ncia renal aguda foi uma complica??o freq?ente, sem, no entanto, evoluir para a insufici?ncia renal cr?nica. A mortalidade xii materna foi baixa 0,4% e a mortalidade perinatal alta de 223 por 1000 nascidos vivos. O risco de uma mulher, cuja m?e teve hipertens?o ou pr?-ecl?mpsia, vir a ter pr?-ecl?mpsia ?, respectivamente, 2,5 e 3,5 vezes. Esse risco aumenta para cinco vezes, quando a irm? tem antecedente de hipertens?o e seis vezes quando, tanto a m?e quanto a irm? t?m antecedentes de pr?-ecl?mpsia. Conclus?es: Este estudo confirma a agrega??o familiar da pr?-ecl?mpsia em popula??o brasileira. O risco aumentado para doen?as cardiovasculares e hipertens?o cr?nica nestas mulheres, indica a necessidade de seguimento das pacientes que desenvolvem pr?-ecl?mpsia
1073

Sistemas de informa??o geogr?fica e an?lise espacial de dados como ferramentas para determina??o de agrega??o espacial de doen?as: a hansen?ase como modelo

Queiroz, Jos? Wilton de 05 October 2009 (has links)
Made available in DSpace on 2014-12-17T14:13:35Z (GMT). No. of bitstreams: 1 JoseWQ_TESE.pdf: 1778874 bytes, checksum: 7ff2c9f470b5b3873803d39a321ee362 (MD5) Previous issue date: 2009-10-05 / This work demonstrates the importance of using tools used in geographic information systems (GIS) and spatial data analysis (SDA) for the study of infectious diseases. Analysis methods were used to describe more fully the spatial distribution of a particular disease by incorporating the geographical element in the analysis. In Chapter 1, we report the historical evolution of these techniques in the field of human health and use Hansen s disease (leprosy) in Rio Grande do Norte as an example. In Chapter 2, we introduced a few basic theoretical concepts on the methodology and classified the types of spatial data commonly treated. Chapters 3 and 4 defined and demonstrated the use of the two most important techniques for analysis of health data, which are data point processes and data area. We modelled the case distribution of Hansen s disease in the city of Mossor? - RN. In the analysis, we used R scripts and made available routines and analitical procedures developed by the author. This approach can be easily used by researchers in several areas. As practical results, major risk areas in Mossor? leprosy were detected, and its association with the socioeconomic profile of the population at risk was found. Moreover, it is clearly shown that his approach could be of great help to be used continuously in data analysis and processing, allowing the development of new strategies to work might increase the use of such techniques in data analysis in health care / O presente trabalho demonstra a import?ncia do uso de ferramentas relacionadas ? sistemas de informa??o geogr?fica (SIG) e an?lise espacial de dados (AED) em estudos de doen?as infecciosas. M?todos de an?lise foram usados para descrever de forma mais abrangente a distribui??o espacial de doen?as a partir da incorpora??o do elemento geogr?fico na an?lise. No Cap?tulo 1 relata-se a evolu??o hist?rica da aplica??o destas t?cnicas no campo da sa?de humana e elege-se a hansen?ase no estado do Rio Grande do Norte como exemplo de aplica??o. No Cap?tulo 2 introduzem-se alguns conceitos te?ricos b?sicos sobre a metodologia e classificam-se os tipos de dados espaciais comumente tratados. Os Cap?tulos 3 e 4 definem e demonstram a utiliza??o das mais importantes t?cnicas de an?lise para os dois principais tipos de dados encontrados na sa?de, quais sejam dados de processos pontuais e dados de ?rea, focalizando como estudo de caso a hansen?ase na cidade de Mossor? RN. Na an?lise, ? priorizada a utiliza??o do sistema R, disponibilizando-se scripts de rotinas e procedimentos de an?lise desenvolvidos pelo autor que podem ser facilmente utilizados por pesquisadores de diversas ?reas. Como resultados pr?ticos, importantes ?reas de risco da hansen?ase em Mossor? foram detectadas e sua forte associa??o com o perfil socioecon?mico da popula??o sob risco foi constatada. Al?m disso, estima-se que este trabalho possa vir a incrementar a utiliza??o de tais t?cnicas na an?lise de dados na ?rea de sa?de
1074

Conservação e viabilidade do plasma rico em plaquetas de coelhos sob refrigeração

Silva, Lucas Vilela Perroni 26 June 2015 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / In the development of this research, 15 New Zealand rabbits were used, with the aim of storing platelet-rich plasma (PRP) during 30 days refrigerated at 4-6oC. There was a preparation of 30 samples of PRP which were sorted in three equal groups. Every three days a sample would be removed for evaluation, before and after storage, for the number of platelets, mean platelet volume (MPV), pH of the plasma, aggregation post addition of calcic thromboplastin and for the presence of bacterial and fungal contamination. In the variables of number of platelets, there was no linear relationship in function of time, when comparing the number of platelets before x after storage, a statistical difference was observed. The hemogram MPV variables, before and after storage also did not relate with time, however there was a statistical difference in the comparisons of MPV on blood count x MPV before storage and of MPV before storage x MPV post storage. On the evaluation of the pH there was no influence of time on the variables, but statistical differences were found in the samples after storage in between the periods of 30 and 6; 30 and 24; 30 and 27 days. Platelet aggregation occurred within twenty seconds in all samples independent of storage time. There was no growth of bacteria or yeast in any sample, however mold growth occurred in the samples 21 days of storage on group one and three. It can be concluded that platelet-rich plasma of rabbits can be stored under refrigeration of 4 to 6 °C for maintaining the number of platelets, without significant pH alteration and absence of bacterial or fungal contamination during 18 days. / Utilizou-se 15 coelhos da raça Nova Zelândia para o desenvolvimento da pesquisa, com o objetivo de armazenar plasma rico em plaquetas (PRP) durante 30 dias sob refrigeração de 4-6ºC. Preparou-se 30 amostras de PRP que foram divididas em três grupos iguais. A cada três dias uma amostra foi retirada para avaliação antes e após o armazenamento quanto ao número de plaquetas, volume plaquetário médio (VPM), pH do plasma, agregação pós adição de tromboplastina cálcica e presença de contaminação bacteriana e fúngica. Nas variáveis número de plaquetas, não houve relação linear em função do tempo, na comparação do número de plaquetas pré x pós armazenamento, observou-se diferença estatística. As variáveis de VPM do hemograma, pré e pós armazenamento também não apresentaram relação com o tempo, porém obteve-se diferença estatística nas comparações VPM no hemograma x VPM pré armazenamento e VPM pré-armazenamento x VPM pós armazenamento. Na avaliação do pH não houve influência do tempo nas variáveis, mas houve diferença estatística nas amostras pós armazenamento entre os períodos 30 e 6; 30 e 24; 30 e 27 dias. A agregação plaquetária ocorreu dentro de vinte segundos em todas as amostras independente do tempo de estocagem. Não houve crescimento bacteriano e de leveduras em nenhuma amostra, porém ocorreu crescimento de bolores nas amostras 21 dias de armazenamento dos grupos um e três. Pode-se concluir que o plasma rico em plaquetas de coelhos pode ser armazenado sob refrigeração de 4 a 6ºC por manter o número de plaquetas, sem alteração significativa do pH e ausência de contaminação bacteriana e fúngica durante18 dias. / Mestre em Ciências Veterinárias
1075

Caracterização funcional da BaltMTx, uma miotoxina isolada da peçonha de Bothrops alternatus

Pereira, Déborah Fernanda da Cunha 30 June 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / CAPÍTULO II: Peçonhas de serpentes são uma mistura complexa de compostos orgânicos e inorgânicos, proteínas e peptídeos, tais como as aminotransferases, acetilcolinesterases, hialuronidases, L-aminoácido-oxidases, fosfolipases A2, metaloproteases, serinoproteases, lectinas, desintegrinas, entre outros. As fosfolipases A2 influenciam direta ou indiretamente no efeito fisiopatológico no envenenamento, pois além de sua participação na digestão das presas, elas apresentam várias outras atividades como ação hemolítica indireta, neurotoxicidade, cardiotoxicidade, ação agregadora de plaquetas, atividades anticoagulante, edematogênica, miotóxica e inflamatória. Neste trabalho, descrevemos a caracterização funcional de BaltMTx, uma PLA2 de Bothrops alternatus que inibe a agregação plaquetária e apresenta efeito bactericida. A purificação de BaltMTx foi realizada por uma combinação de três passos cromatográficos (cromatografia de troca iônica em DEAE-Sephacel, seguido de cromatografia de interação hidrofóbica em Phenyl-Sepharose, e cromatografia de afinidade em Heparina HiTrap™ HP). A proteína foi purificada até à homogeneidade, tal como avaliado pelo seu perfil de migração em SDS-PAGE, corado com azul de Coomassie, que mostrou uma massa molecular de cerca de 15 kDa sob condições redutoras e cerca de 25 kDa em condições não redutoras. BaltMTx mostrou um efeito inibidor específico sobre a agregação plaquetária induzida por epinefrina em plasma humano rico em plaquetas, de uma maneira dose dependente. Todavia, apresentou pouco ou nenhum efeito sobre a agregação plaquetária induzida por colágeno e adenosinadifosfato. BaltMTx, também, mostrou atividade antibacteriana contra Staphylococcus aureus e Escherichia coli. Altas concentrações de BatlMTx estimulou a proliferação de Leishmania (Leishmania) infantum e Leishmania (Viania) braziliensis. BaltMTx induziu a produção de mediadores inflamatórios tais como IL-10, IL-12, TNF-α e NO. BaltMTx apresenta grande interesse médico, tanto como uma nova ferramenta para o desenvolvimento de novos agentes terapêuticos para a prevenção e tratamento de distúrbios trombóticos, quanto como agente bactericida. / CHAPTER II: Snake venoms are a complex mixture of organic and inorganic compounds, proteins and peptides such as aminotransferases, acetylcholinesterase, hyaluronidases, L-amino acid oxidase, phospholipase A2, metalloproteases, serine proteases, lectins, disintegrins, and others. Phospholipase A2 directly or indirectly influence the pathophysiological effect on envenomation, as well as their participation in the digestion of the prey. They have several other activities such as hemolytic indirect action, cardiotoxicity, aggregating of platelets, anticoagulant, edema, myotoxic and inflammatory activities. In this work, we describe the functional characterization of BaltMTx, a PLA2 from Bothrops alternatus that inhibits platelet aggregation and present bactericidal effect. The purification of BaltMTx was carried out through three chromatographic steps (ion-exchange on a DEAE-Sephacel column, followed by hydrophobic chromatography on Phenyl–Sepharose and affinity chromatography on HiTrap™ Heparin HP). The protein was purified to homogeneity as judged by its migration profile in SDS–PAGE stained with coomassie blue, and showed a molecular mass of about 15 kDa under reducing conditions and approximately 25 kDa in non-reducing conditions. BaltMTx showed a rather specific inhibitory effect on platelet aggregation induced by epinephrine in human platelet-rich plasma in a dose-dependent manner, whereas it had little or no effect on platelet aggregation induced by collagen or adenosine diphosphate. BaltMTx also showed antibacterial activity against Staphylococcus aureus and Escherichia coli. High concentrations of BatlMTx stimulated the proliferation of Leishmania (Leishmania) infantum and Leishmania (Viania) braziliensis. BaltMTx induced production of inflammatory mediators such as IL-10, IL-12, TNF-α and NO. BaltMTx could be of medical interest as a new tool for the development of novel therapeutic agents for the prevention and treatment of thrombotic disorders as well as bactericidal agent. / Dissertação (Mestrado)
1076

Da produção ao consumo de vinho orgânico no brasil : limitações, significado e perspectivas

Araujo, Marcos Vinícius January 2017 (has links)
Adotando novos hábitos de consumo, os consumidores passaram a ser mais exigentes e conscientes de que suas práticas de consumo impactam na dinâmica ambiental, social e econômica, de forma a explorar o uso de recursos e quantidade de resíduos descartados na natureza. Essas mudanças são práticas do consumo consciente e responsável, o que é tido como politização do consumo. Percebendo isso, empresas de vários segmentos se adaptaram para fornecer produtos e serviços que atendam a essas exigências dos consumidores. Dentro dessa dinâmica, incluem-se os alimentos orgânicos, biodinâmicos, naturais e com práticas sustentáveis integradas em seus processos produtivos. Nessa perspectiva, vinícolas brasileiras iniciaram a produção de uvas orgânicas para produção de vinhos e, posteriormente, para produção de suco de uva. Contudo, devido às dificuldades climáticas e limitações de técnicas produtivas, essas vinícolas depararam-se com obstáculos para o fornecimento do vinho orgânico, seja pela questão técnica do sistema orgânico, ou mesmo pela forma de relacionamento de mercado, que faz com que o valor de orgânico e sustentável não chegue integralmente aos públicos de interesse. A partir da realidade produtiva do vinho orgânico, questiona-se, então, qual o panorama atual e futuro para o vinho orgânico. Nesse sentido, o objetivo desse trabalho é compreender a dinâmica da produção e consumo desse produto, a partir da implementação e manutenção de valor, descrição e análise das limitações produtivas, percepção de valor e análise do atual e futuro panorama do setor. Para a realização desse estudo, desenvolveu-se uma pesquisa exploratória com os principais atores dessa cadeia. Foram entrevistadas e visitadas 05 (cinco) vinícolas, sendo 04 (quatro), das 06 (seis) existentes no Brasil, que produzem suco e vinho orgânicos e que possuem mix completo de produtos convencionais e a vinícola que produziu o primeiro vinho fino orgânico brasileiro, um representante do setor vitivinícola, um intermediário de comercialização e 20 (vinte) consumidores, além de busca de evidências em visitas a supermercados e internet. Os dados foram analisados a partir do cruzamento dos dados coletados, com análise de conteúdo simples, para então retirar temas que surgiram nas entrevistas com esses atores. Os resultados mostram que as vinícolas ainda têm dificuldade na implementação e comunicação do valor do vinho orgânico, bem como apresenta limitações nos processos produtivos, sobretudo por questões técnicas e climáticas. Contudo, já existem esforços para solucionar essas questões, como pesquisas e atividades para colaborar com os produtores de uva, principalmente em busca de técnicas para a produção orgânica. Com relação ao consumidor final, verifica-se que o valor ainda não chega a ele em sua integralidade, especialmente no que se refere a outras ações de sustentabilidade realizadas pelas vinícolas. Por outro lado, os consumidores percebem como um vinho de má qualidade, principalmente devido à variedade de uva utilizada para sua elaboração, levando à discussão sobre a adoção de práticas sustentáveis e fornecimento de um produto intermediário, entre orgânico e convencional, para em um futuro próximo se chegar à produção de um vinho fino orgânico que satisfaça a expectativa do consumidor final. / Adopting new consumption habits, consumers have became more demanding and conscious that their consumption practices impact on the environmental, social and economic dynamics, in order to worry about the exaggerated use of resources and quantity of waste used and discarded in nature. These are practices of conscious and responsible consumption, which are part of the politicization of consumption. Aware of this, companies from various segments have adapted to provide products and services that meet these consumer demands, in this dynamic, including organic, natural, biodynamic foods and that have sustainable practices integrated into their processes of production. In this perspective, Brazilian wineries began the production of organic grapes for wine production and later for the production of organic grape juice. However, due to the climatic difficulties and limitations of productive techniques, there were obstacles in the supply of this product, either by the technical question of the organic system or even by the form of market relationship, which does not reach there target public. It is questioned, therefore, from the organic wine production reality, its present and future panorama, in order to understand the dynamics of the production and consumption of this product, from the implementation and maintenance of value, description and analysis of the productive limitations, value perception and analysis of the current and future panorama of the sector. To carry out this study, an exploratory research was developed with the main actors of this chain, interviewing and visiting 05 (five) wineries, 04 (four) of 06 (six) existing in Brazil, that produce organic juice and wine and have a complete chain of conventional products and 01(one) interview with the winery that produced the first Brazilian organic fine wine, interview with 01 (one) representative of the sector, 01 (one) marketing intermediary and 20 (twenty) consumers, as well as search for evidences in visits to supermarkets and internet. The data were analyzed from the cross-tabulation of the data collected, using simple content analysis, and then themes emerged during the interviews with these actors. The results show that the wineries still have difficulty in implementing and communicating the value of this product, it has limitations in the productive processes, mainly due to technical and climatic issues. However, there are already efforts to address these issues, such as research and activities to collaborate with producers, mainly in search of techniques for organic production. On the other hand, the value still does not reach the final consumer, especially with regard to other sustainability actions carried out by the wineries. On the other hand, consumers still perceive as a product of poor quality, with regard to the taste and variety of grapes, which leads to a discussion on the adoption of sustainable practices and to provide an intermediate product, between organic and conventional, in the near future to obtain the production of an organic fine wine (from Vitis Vinifera grapes) that meets the expectations of the final consumer.
1077

Apport de l’analyse temps-fréquence combinée à l’analyse de formes pour le traitement ISAR

Corretja, Vincent 30 January 2013 (has links)
Dans le cadre de la surveillance maritime, les opérationnels ont de plus en plus recours à l'imagerie radar pour classifier à grande distance un objet marin. Le traitement ISAR (Inverse Synthetic Aperture Radar) répond à ce besoin. Il repose en particulier sur l'analyse des mouvements propres de l'objet marin. Une fois l'objet détecté, il s'agit d'afficher sur la console tactique la représentation de la fréquence Doppler en fonction de la distance, aussi appelée image range-Doppler. Le travail présenté dans ce mémoire s'inscrit dans une perspective d'évolution opérationnelle de la chaîne de traitement existante. Il vise à produire de manière automatique la « meilleure » image range-Doppler. Dans cette thèse, nos contributions s'appuient sur l'idée de reconsidérer la chaîne de traitement en tenant compte de l'a priori que l'objet marin est un objet rigide dont la géométrie structure l'évolution du signal radar. Ainsi, dans une première contribution, nous proposons une nouvelle méthode d'analyse temps-fréquence du signal radar afin d'obtenir une image instantanée où l'opérationnel peut distinguer « au mieux » les superstructures de l'objet marin. Cette dernière est fondée sur la fusion de plusieurs représentations temps-fréquence issues de la classe de Cohen en faisant l'hypothèse que les composantes temps-fréquence sont des trajectoires structurées 2D dans le plan temps-fréquence, contrairement aux termes d'interférences induits par la propriété de bilinéarité des membres de cette classe. Une étude comparative sur données synthétiques et ISAR est menée pour confirmer la pertinence de notre approche, notamment du point de vue de la résolution temps-fréquence et de la suppression des termes d'interférences.Dans une seconde contribution, nous établissons une nouvelle procédure pour qualifier chaque image range-Doppler, obtenue à l'issue de l'analyse temps-fréquence, avec des mesures d'irrégularité de formes que nous fusionnons à l'aide d'un opérateur d'agrégation. Des simulations sur données réelles sont réalisées. Les résultats concordent avec une analyse subjective menée par des opérationnels, ce qui confirme l'efficacité de notre méthode. / In maritime surveillance, radar imaging plays a key role to classify a maritime object. ISAR processing is one of the solutions, which takes advantage of the object rotational motion to provide a range-Doppler image.The work, presented in this report, is an evolution of the existing ISAR processing chain. Therefore, our contributions are based on the processing chain reconsideration by taking into account the fact that the maritime object is a rigid object, the geometry of which influences the radar signal evolution.In a first contribution, we propose a new time-frequency analysis method based on the aggregation of some time-frequency representations obtained with Cohen class members. It consists in differentiating the signal, assumed to be characterized by 2-D near-linear stable trajectories in the time-frequency plane, and the cross-terms, assumed to be geometrically unstructured. A comparative study is then carried out on ISAR synthetic data to confirm the efficiency of our approach.In a second contribution, we present a new procedure to characterize each range-Doppler image, obtained from a time-frequency analysis, by means of shape irregularity measures that are combined with a fuzzy logic operator. To validate our approach, simulations on real data are done. The results are compared to a subjective analysis carried out with practionners.
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Athérosclérose : approche translationnelle de la détection, caractérisation, et du traitement de la plaque athéromateuse / Atherosclerosis : translational approach of the detection, characterization, and treatment of atheromatous plaque

Didier, Romain 21 June 2018 (has links)
L’athérosclérose est une pathologie artérielle chronique évoluant sur plusieurs années ou dizaines d’années. Sa traduction clinique est variable, pouvant rester longtemps asymptomatique, ou induire des symptômes d’effort directement lié à la réduction du calibre de l’artère (angor, claudication des membres inférieurs). Malgré cette évolution en apparence lente et progressive, les manifestations cliniques aiguës de cette pathologie sont souvent de survenue brutale. La formation de thrombus en regard des lésions athéromateuses dites déstabilisées représente la composante physiopathologique la plus fréquemment rencontrée. Cette complication aigüe de la plaque athéromateuse est responsable d’événements cardio-vasculaires majeurs impactant la morbi-mortalité, représentés par les syndromes coronariens aigus, les accidents vasculaires cérébraux ischémiques, et les ischémies aigues de membre inférieur. Après une revue des connaissances actuelles sur la plaque athéromateuse, nous étudierons à l’aide d’un modèle animal d’athérosclérose, son évolution, ses caractéristiques morphologiques, et nous testerons l’impact d’un traitement au long cours par statine en prévention primaire sur les plaques athéromateuses et sur les composants de la paroi vasculaire. Puis, dans une approche clinique, nous nous intéresserons à la durée optimale du traitement par double antiagrégant plaquettaire instauré après un traitement par angioplastie percutanée de plaque athéromateuse. Dans un second temps, nous détaillerons l’évolution des pratiques d’angioplastie coronaire en analysant les facteurs ayant contribué à limiter l’utilisation des stents non actifs (dit nus) au cours des 10 dernières années. Enfin, nous étudierons les principaux facteurs restant associés à la survenue d’un accident vasculaire cérébral post angioplastie percutanée, correspondant à l’une des principales complications majeures de ces procédures. / Atherosclerosis is a chronic arterial disease that progresses over several years or decades. Its clinical translation is variable, and may remain asymptomatic for a long time, or induce symptoms of stress directly related to the reduction in size of the artery (angina, chronic limb ischemia). Despite this seemingly slow and progressive evolution, the acute clinical manifestations of this pathology often occur suddenly. Thrombus formation in regard to the “destabilized” atheromatous lesions is the most frequently physiopathological components. This acute complication of atheromatous plaque is responsible of major cardiovascular events impacting the morbi-mortality, mostly represented by acute coronary syndromes, ischemic strokes, and acute lower limb ischemia. After a review of current knowledge on atheromatous plaque, we will study using an animal model of atherosclerosis, its evolution, its morphological characteristics, and we will test the impact of a long-term statin treatment in primary prevention on atheromatous plaques and on vascular wall components. Then, in a clinical approach, we will look at the optimal duration of double platelet antiaggregant after angioplasty. In a second step, we will detail the evolution of coronary angioplasty practices by analyzing the main factors that have contributed to limiting the use of bare metal stent over the past 10 years. Finally, we will analyze the major factors still associated with the occurrence of a stroke after percutaneous angioplasty.
1079

On Social Choice in Social Networks

Becirovic, Ema January 2017 (has links)
Kollektiva beslut blir en del av vardagen när grupper av människor står inför val. Vi anpassar ofta våra personliga övertygelser med hänsyn till våra vänner. Vi är naturligt beroende av lyckan hos dem som står oss nära. I det här exjobbet undersöker vi en befintlig empatimodell som används för att välja en vinnare från en uppsättning alternativ genom att använda poängbaserade omröstningsprocedurer. Vi visar att en liten modifikation av modellen är tillräcklig för att kunna använda överlägsna omröstningsprocedurer som bygger på parvisa jämförelser av alternativen. Sammanfattningsvis visar vi att det i grunden inte finns någon anledning att använda poängbaserade omröstningsprocedurer i de föreslagna modellerna, eftersom ett mer önskvärt resultat uppnås genom att använda de överlägsna omröstningsprocedurerna. / Social choice becomes a part of everyday life when groups of people are faced with decisions to make. We often adjust our personal beliefs with the respect to our friends. We are inherently dependent on the happiness of those near us. In this thesis, we investigate an existing empathy model that is used to select a winner in a set of alternatives by using scoring winner selection methods. We show that a slight modification of the model is enough to be able to use superior winner selection methods that are based on pairwise comparisons of alternatives. We show that there is essentially no reason to use scoring winner selection methods in the models proposed as a more desirable result is achieved by using superior winner selection methods.
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Modélisation de hiérarchies complexes dans les entrepôts de données XML et traitement des problèmes d'additivité dans l'analyse en ligne XOLAP / Modeling complex hierarchies in XML data warehouses and solving summarizability problems in XOLAP

Hachicha, Marouane 26 November 2012 (has links)
Depuis son apparition en 1998, le langage XML (eXtensible Markup Language) est devenu un standard pour la modélisation et l'échange de données. En effet, XML permet de modéliser des structures de données qui ne sont pas facilement représentées dans les systèmes relationnels. Dans ce contexte, les entrepôts de données XML représentent aujourd'hui la base de plusieurs applications décisionnelles qui exploitent des données hétérogènes (peu structurées et provenant des sources multiples) aux structures complexes comme par exemple des hiérarchies complexes.Dans ce mémoire, nous proposons une nouvelle solution XOLAP (XML-OLAP) en temps réel qui traite les problèmes d'additivité dus aux hiérarchies complexes. Tout d'abord, nous proposons un nouveau modèle de données : les arbres de données multidimensionnels, qui permet de modéliser les faits, les dimensions, les mesures et les hiérarchies complexes d'un entrepôt de données XML. Pour pouvoir interroger les arbres de données multidimensionnels, nous modélisons les requêtes utilisateur à l'aide de modèles d'arbre XML. Nous proposons ensuite un nouvel algorithme de regroupement et d'agrégation pour la résolution en temps réel des problèmes d'additivité dans les hiérarchies complexes. Nous généralisons enfin cet algorithme à un nouvel opérateur XOLAP de forage vers le haut (roll-up).Finalement, nous validons nos propositions de manière expérimentale. Pour cela, nous étendons le banc d'essais XWeB en introduisant des hiérarchies complexes dans son schéma. La comparaison de notre approche à une approche de référence montre que la surcharge due à l'exécution en temps réel de notre approche est tout à fait acceptable et que nos algorithmes sont susceptibles de passer à l'échelle. / Since its inception in 1998, the eXtensible Markup Language (XML) has emerged as a standard for data representation and exchange over the Internet. XML provides an opportunity for modeling data structures that are not easily represented in relational systems. In this context, XML data warehouses nowadays form the basis of several decision-support applications exploiting heterogeneous data (little structured and coming from various sources) bearing complex structures, such as complex hierarchies. In this thesis, we propose a novel XOLAP (XML-OLAP) approach that automatically detects and processes summarizability issues at query time, without requiring any particular expertise from the user. Thus, at the logical level, we choose XML data trees, so-called multidimensional data trees, to model the multidimensional structures (facts, dimensions, measures and complex hierarchies) of XML data warehouses. In order to query multidimensional data trees, we model user queries as XML pattern trees. Then, we introduce a new aggregation algorithm to address summarizability issues in complex hierarchies. On the basis of this algorithm, we propose a novel XOLAP roll-up operator. Finally, we experimentally validate our proposal and compare our approach with the reference approach for addressing summarizability issues in complex hierarchies. For this sake, we extend the XML warehouse benchmark XWeB with complex hierarchies to generate XML data warehouses with scalable complex hierarchies. The results of our experiments show that the overhead induced by managing hierarchy complexity at run-time is totally acceptable and that our approach is expected to scale up well.

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