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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.
461

Estudo da fauna fitonematológica na Mata Atlântica do estado de São Paulo e na Floresta Amazônica do estado do Mato Grosso / Study of the plant parasitic nematode fauna in the Atlantic Forest from São Paulo state and the Amazon Forest from Mato Grosso state, Brazil

Silva, Rosangela Aparecida da 04 April 2008 (has links)
Realizou-se estudo da fauna de fitonematóides em dois municípios do estado de São Paulo (Pariquera-Açu e Cananéia) sob domínio da Mata Atlântica e dois do estado do Mato Grosso (Nova Maringá e Guarantã do Norte) sob domínio da Floresta Amazônica, com o objetivo de conhecer a diversidade de fitonematóides desses biomas e avaliar o efeito do uso agrícola do solo sobre a comunidade de fitonematóides. Para tanto, foram efetuadas amostragens em áreas de vegetação primária e em áreas próximas cultivadas. Para cada amostra, foram extraídos os nematóides de 200 cm³ de solo e em 10 gramas de raízes pela técnica de peneiramento combinada com flutuação em centrífuga com solução de sacarose. Em seguida, os espécimes foram mortos pelo calor e fixados em formalina. Os nematóides foram posteriormente quantificados, para determinação da abundância de cada táxon, sendo as identificações taxonômicas realizadas com base em características morfológicas e morfométricas. Os dados foram analisados com base na abundância, freqüência e índices de similaridade (Jaccard e Bray e Curtis). Assinalaram-se 34 gêneros e as identificações específicas foram efetuadas para 22 táxons. Para a espécie Aorolaimus banoae foram apresentadas novas características morfológicas e morfométricas. Observou-se que, com a retirada da vegetação primária e a implantação dos cultivos de plantas perenes ou anuais, houve intenso processo de redução da diversidade de fitonematóides e da introdução de novos táxons, o que resultou em baixa similaridade entre os locais de vegetação primária e aqueles cultivados, demostrando-se elevada influência da atividade agrícola sobre a comunidade de fitonematóides. / A study about plant parasitic nematode fauna was conducted in two municipalities from São Paulo State (Pariquera-Açu and Cananéia in the Atlantic Forest) and two from Mato Grosso State (Nova Maringá and Guarantã do Norte in the Amazon Forest), Brazil. The aims of this study were to evaluate the diversity of plant-parasitic nematode fauna in locations of primary and to evaluate the effect of agricultural land use on the plant parasitic nematode communities. Nematodes were extracted from 200 cm³ of soil and 10 grams of roots by a sieving and sugar flotations technique and fixed with formalin. Nematodes were counted for determination of abundances of each taxon and the taxonomic identification was based on morphological and morphometric features. The following variables were obtained: abundance, frequency and similarity indexes (Jaccard and Bray e Curtis). A total number of 34 genera were recorded and 22 taxons were identified at species level. Concerning Aorolaimus banoae species, new morphological and morphometric features were presented. It was observed that, after removal of primary vegetation and implantation of perennial or annual crops, occurred a conspicuous reduction of plant parasitic nematode diversity, associated with introduction of exotic species, resulting in low similarity between location of primary vegetation and the cultivated ones. The results demonstrated that the agricultural practices affect strongly the plant parasitic nematode communities.
462

Latenciação de hidroximetilnitrofural com derivados de quitosana, potencialmente ativos em leishmaniose e doença de Chagas / Latentiation of hidroximetilnitrofural derivative chitosan, potentially active in leishmaniasis and Chagas disease

Santos, Katia Solange Cardoso Rodrigues dos 16 May 2005 (has links)
Leishmaniose e doença de Chagas são parasitoses endêmicas causadas, respectivamente, pelos protozoários Leishmania spp. e Trypanosoma cruzi. Ante à escassez de quimioterápicos, à elevada toxicidade dos fármacos disponíveis e à baixa eficácia destes no combate às formas intracelulares, replicantes, dos parasitos há necessidade de buscar novas alternativas quimioterápicas. A atividade tripanomicida do hidroximetilnitrofural, base de Mannich do nitrofural, já era conhecida. O presente trabalho mostra que este derivado também apresenta atividade leishmanicida, quando ensaiado em formas promastigotas de L. amazonensis, L. chagasi e L. baziliensis. Com o objetivo de obter pró-fármacos potencialmente ativos em doença de Chagas e leishmanioses visceral e mucocutânea, planejaram-se e foram sintetizados derivados hidrossolúveis de hidroximetilnitrofural e quitosana, polissacarídeo que apresenta, também, atividade imunomoduladora. Para a aplicação tópica em leishmaniose cutânea sintetizaram-se membranas de quitosana ligada ao hidroximetilnitrofural. Membranas de quitosana copolimerizadas com enxertos de ácido acrílico e metacrilato de hidroxietila foram sintetizadas e avaliadas quanto à biocompatibilidade - trombogenicidade, citotoxicidade e potencial hemolítico. Aquelas com maior teor em metacrilato de hidroxietila não se mostraram citotóxicas, tampouco hemolíticas; aquelas com maior proporção em ácido acrílico, por sua vez, apresentaram excelentes características de intumescimento, mas certo grau de citotoxicidade e hemólise, possivelmente devido à presença de monômeros que não reagiram no material. A ligação do hidroximetilnitrofural à quitosana, por meio de espaçante succínico, produziu prófármaco com propriedades filmogênicas para a aplicação tópica. Os derivados obtidos pró-fármacos e transportadores (quitosanas modificadas) - foram analisados no infravermelho, por ressonância magnética nuclear (RMN 1H e RMN 13C) e por análise térmica - OMTA, TG, OSC. Ensaios de atividade tripanomicida e leishmanicida dos pró-fármacos poliméricos e membranas serão posteriormente efetuados. / Leishmaniasis and Chagas\' disease are endemic parasitosis provoked by the protozoa Leishmania spp and Trypanosoma cruzi, respectively. Due to the scarce chemotherapy, to the high toxicity of the available drugs and to their low effectiveness, mainly in the treatment of intracellular replicant forms of those parasites, the search for new chemotherapeutic alternatives is extremely important. Hydroxymethylnitrofurazone, a nitrofurazone Mannich basis, has proven to be active against trypanomicide before and its activity in cultures of L. amazonensis, L. chagasi and L. braziliensis promastigotes was determined in this work. With the purpose of obtaining prodrugs potentially active in Chagas\' disease and visceral and mucocutaneous leishmaniases, hydrosoluble hydroxymethylnitrofurazone prodrugs have been designed and synthesized using chitosan, a polysaccharide showing immunomudulatory activity, as the carrier. Membranes from chitosan linked with hydroxymethylnitrofurazone have been synthesized for topical administration in cutaneous leishmaniasis. Membranes were obtained by graft copolymerization of hydroxyethy/methacrylate and acrylic acid onto chitosan and their biocompatibility - trombogenicity, citotoxicity and hemolysis potential - was evaluated. Those membranes with higher content of hydroxyethylmethacrylate showed to be neither cytotoxic nor hemolytic; those with higher content of acrylic acid showed good swelling properties, although a certain level of cytotoxicity and haemolysis has been detected, due to the presence of non-reacted monomers. The linkage of hydroxymethylnitrofurazone to chitosan by a succinyl spacer group led to a prodrug with filmogenic properties for topic administration. The derivatives obtained - prodrugs and carriers (modified chitosans) - were analyzed by infrared, nuclear magnetic resonance (1H NMR and 13C NMR) and by thermal analysis - DMTA, TG and DSC. Tests of trypanomicide and leishmanicide activity with polymer prodrugs and membranes will be further developed.
463

Forma y función de los juegos fónicos en el habla juvenil de Puebla (México)

Boyer, Julie 07 1900 (has links)
Dans le parler des jeunes du Mexique, on retrouve, entre autres formes de vitalité linguistique, un usage fréquent de jeux phoniques qui transforment ou substituent des lexèmes et syntagmes sans qu'il y ait altération significative du signifié. Ce phénomène linguistique utilise trois procédés phoniques: la suffixation parasitaire, la substitution lexicale basée sur la similitude phonique et l'enchaînement en écho. Le présent mémoire contribue à remplir un vide dans la littérature scientifique et faire connaître ce phénomène peu étudié en explorant les aspects formels linguistiques et les fonctions sociales. Nous cherchons à établir les relations qui existent entre la structure linguistique et les fonctions linguistiques et sociales inhérentes à l'usage de jeux phoniques. L'étude empirique menée dans la ville de Puebla (Mexique) a permis la collecte d'un corpus de plus de deux cents jeux phoniques et la réalisation d'entrevues sociolinguistiques avec dix-huit jeunes de Puebla usagers des expressions étudiées. Nous proposons une classification du corpus de jeux phoniques basée sur la structure formelle afin d'apprécier que le phénomène réponde à des patrons fixes de construction. Suite à une analyse thématique des entrevues que nous appuyons d'exemples de jeux phoniques, nous verrons que l'usage de jeux phoniques joue principalement une fonction poétique, ludique ainsi qu'une fonction de cohésion sociale et une fonction identitaire. La présente étude confirme que le caractère non normatif et cryptique intrinsèque aux jeux de mots sert à renforcer ces fonctions sociales, à la manière d'un parler argotique. / In the youth speech of Mexico a frequent use of phonic wordplays that transform or substitute lexemes and phrases without significant alteration of the signifier are found among linguistic vitality signs. This linguistic phenomenon uses three phonic techniques: parasitic suffixation, lexical substitution based on phonic similarity and echo chaining. This report contributes by filling a void in the scientific literature and to expose this overlooked phenomenon by exploring its formal linguistic aspects and social functions. The aim of this study is to establish the relationship between linguistic structure and linguistic and social functions inherent to phonic wordplay use. The empiric study conducted in Puebla (Mexico) allowed the collection of a corpus of more than two hundred phonic wordplays and the realization of sociolinguistic interviews with eighteen Puebla youth, who employ the studied expressions. This work proposes a classification of the corpus based on their formal structure in order to highlight that the phenomenon conforms to fixed patterns of construction. After a thematic analysis of the interviews, with an emphasis on phonic wordplay examples, we observe that the use of phonic wordplays mainly accomplishes poetic and ludic, as well as social cohesion and identity functions. This study confirms that the non-normative and cryptic characteristics intrinsic to phonic wordplays help to reinforce the aforementioned social functions as an argotic speech. / En el habla de los jóvenes de México encontramos, entre otras muestras de vitalidad lingüística, un uso frecuente de juegos fónicos que transforman o sustituyen lexemas y sintagmas sin que haya alteración significativa del significado. Este fenómeno lingüístico utiliza tres recursos fónicos: la sufijación parasitaria, la sustitución léxica por similitud fónica y el encadenamiento en eco. La presente memoria contribuye a llenar un vacío en la literatura científica y dar a conocer este fenómeno poco estudiado, explorando los aspectos formales lingüísticos y las funciones sociales. Buscamos establecer las relaciones que existen entre la estructura lingüística y las funciones lingüísticas y sociales inherentes al uso de los juegos fónicos. El estudio empírico que se llevó a cabo en la ciudad de Puebla (México) permitió la recolección de un corpus de más de doscientos juegos fónicos y la realización de entrevistas sociolingüísticas con dieciocho jóvenes poblanos usuarios de las expresiones estudiadas. Proponemos una clasificación del corpus de juegos fónicos basada en la estructura formal para apreciar que el fenómeno responde a patrones fijos de construcción. Tras un análisis temático de las entrevistas, que apoyamos con ejemplos de juegos fónicos, veremos que el uso de juegos fónicos cumple principalmente una función poética, lúdica, así como una función de cohesión social y una función identitaria. El presente estudio confirma que el carácter no normativo y críptico intrínseco a los juegos fónicos sirve para reforzar estas funciones sociales, a modo de habla argótica.
464

System Interconnection Design Trade-offs in Three-Dimensional (3-D) Integrated Circuits

Weerasekera, Roshan January 2008 (has links)
Continued technology scaling together with the integration of disparate technologies in a single chip means that device performance continues to outstrip interconnect and packaging capabilities, and hence there exist many difficult engineering challenges, most notably in power management, noise isolation, and intra and inter-chip communication. Significant research effort spanning many decades has been expended on traditional VLSI integration technologies, encompassing process, circuit and architectural issues to tackle these problems. Recently however, three- dimensional (3-D) integration has emerged as a leading contender in the challenge to meet performance, heterogeneous integration, cost, and size demands through this decade and beyond. Through silicon via (TSV) based 3-D wafer-level integration is an emerging vertical interconnect methodology that is used to route the signal and power supply links through all chips in the stack vertically. Delay and signal integrity (SI) calculation for signal propagation through TSVs is a critical analysis step in the physical design of such systems. In order to reduce design time and mirror well established practices, it is desirable to carry this out in two stages, with the physical structures being modelled by parasitic parameters in equivalent circuits, and subsequent analysis of the equivalent circuits for the desired metric. This thesis addresses both these issues. Parasitic parameter extraction is carried out using a field solver to explore trends in typical technologies to gain an insight into the variation of resistive, capacitive and inductive parasitics including coupling effects. A set of novel closed-form equations are proposed for TSV parasitics in terms of physical dimensions and material properties, allowing the electrical modelling of TSV bundles without the need for computationally expensive field-solvers. Suitable equivalent circuits including capacitive and inductive coupling are derived, and comparisons with field solver provided values are used to show the accuracy of the proposed parasitic parameter models for the purpose of performance and SI analysis. The deep submicron era saw the interconnection delay rather than the gate delay become the major bottleneck in modern digital design. The nature of this problem in 3-D circuits is studied in detail in this thesis. The ubiquitous technique of repeater insertion for reducing propagation delay and signal degradation is examined for TSVs, and suitable strategies and analysis techniques are proposed. Further, a minimal power smart repeater suitable for global on-chip interconnects, which has the potential to reduce power consumption by as much as 20% with respect to a traditional inverter is proposed. A modeling and analysis methodology is also proposed, that makes the smart repeater easier to amalgamate in CAD flows at different levels of hierarchy from initial signal planning to detailed place and route when compared to alternatives proposed in the literature. Finally, the topic of system-level performance estimation for massively integrated systems is discussed. As designers are presented with an extra spatial dimension in 3-D integration, the complexity of the layout and the architectural trade-offs also increase. Therefore, to obtain a true improvement in performance, a very careful analysis using detailed models at different hierarchical levels is crucial. This thesis presents a cohesive analysis of the technological, cost, and performance trade-offs for digital and mixed-mode systems, outlining the choices available at different points in the design and their ramifications / QC 20100916
465

Fast wave heating and current drive in tokamaks

Laxåback, Martin January 2005 (has links)
This thesis concerns heating and current drive in tokamak plasmas using the fast magnetosonic wave in the ion cyclotron range of frequencies. Fast wave heating is a versatile heating method for thermonuclear fusion plasmas and can provide both ion and electron heating and non-inductive current drive. Predicting and interpreting realistic heating scenarios is however difficult due to the coupled evolution of the cyclotron resonant ion velocity distributions and the wave field. The SELFO code, which solves the coupled wave equation and Fokker-Planck equation for cyclotron resonant ion species in a self-consistent manner, has been upgraded to allow the study of more advanced fast wave heating and current drive scenarios in present day experiments and in preparation for the ITER tokamak. Theoretical and experimental studies related to fast wave heating and current drive with emphasis on fast ion effects are presented. Analysis of minority ion cyclotron current drive in ITER indicates that the use of a hydrogen minority rather than the proposed helium-3 minority results in substantially more efficient current drive. The parasitic losses of power to fusion born alpha particles and beam injected ions are concluded to be acceptably low. Experiments performed at the JET tokamak on polychromatic ion cyclotron resonance heating and on fast wave electron current drive are presented and analysed. Polychromatic heating is demonstrated to increase the bulk plasma ion to electron heating ratio, in line with theoretical expectations, but the fast wave electron current drive is found to be severely degraded by parasitic power losses outside of the plasma. A theoretical analysis of parasitic power losses at radio frequency antennas indicates that the losses can be significantly increased in scenarios with low wave damping and with narrow antenna spectra, such as in electron current drive scenarios. / QC 20100506
466

Contrôle du rayonnement des antennes miniatures / Radiation pattern control in electrically small antennas

Belmkaddem, Kawtar 11 May 2015 (has links)
Dans le contexte actuel où l’évolution des systèmes sans-fil est jugée importante, il estnécessaire de pouvoir réduire les pollutions électromagnétiques qui limitent l’acceptabilité descommunications et la cohabitation des systèmes. D’une façon générale, les besoins de contrôle durayonnement des antennes miniatures répondent donc à une demande croissante pour améliorer lesportées mais aussi pour limiter les interférences dans les systèmes sans-fil. Ces dernières années,malgré le développement connu dans les domaines des antennes, la question du contrôle durayonnement des antennes miniatures connait plusieurs barrières empêchant leur déploiementtechnologique. L’approche retenue dans le cadre de cette thèse est le développement de nouveauxconcepts de contrôle du rayonnement des antennes miniatures par la mise en oeuvre de différentestechniques. Cette étude a pour objectif de soulever quelques questions concernant un sujet d’étude peuexploré. / In the current context where the evolution of communicating objects is important indifferent growing fields such as: localization, wireless multimedia systems, etc., controlling theradiation pattern of antennas is one of the most important issues for future radio communicationsystems. In recent years, despite the growth experienced in the areas of antennas, the issue of smallantennas radiation control knows several barriers preventing their deployment. This thesis focuses onthe analysis of the problem of controlling the radiation pattern of small antennas and aims to raisesome questions about a little-explored subject of study. This work gives an approach using differenttechniques to develop new concepts of controlling the radiation pattern of antennas.
467

Alimentation électrique des dispositifs de décharge à barrière diélectrique / Power supplies for dielectric barrier controlled discharges devices

Bonnin, Xavier 10 December 2014 (has links)
Les dispositifs DBD se répandent dans un grand nombre d’applications industrielles. Utilisés depuis plus de 150 ans pour la production d’ozone afin de décontaminer l’eau à grande échelle, ils ont depuis la fin du XXème siècle investi les domaines du traitement de surface polymère, du dépôt de couche mince sur substrat et de l’émission lumineuse pour la décontamination ainsi que la médecine. Ces dispositifs sont mis en oeuvre avec un générateur électrique dont les caractéristiques impactent fortement la qualité de la décharge. Ce travail s’inscrit en partie dans le cadre du développement d’une application de traitement de surface à pression atmosphérique. Il aborde la problématique de l’augmentation de la vitesse de dépôt de couche mince au travers des paramètres de l’alimentation électrique. Plus précisément, ce travail s’intéresse aux apports d’une alimentation en courant rectangulaire et aborde également les problématiques liées à la conception et à la fabrication de ce convertisseur. En particulier, une grande attention est portée sur l’étude du transformateur élévateur, car au travers de ses éléments parasites capacitifs, ce dernier peut limiter le transfert de puissance entre la source électrique et le dispositif DBD. Un deuxième aspect de cette étude consiste à entrevoir l’intérêt que revêtent deux convertisseurs statiques dédiés à l’alimentation de dispositifs DBD. Le premier consiste en une alimentation résonante en régime de conduction discontinue dont la particularité est de posséder trois degrés de liberté (fréquence, tension d’entrée et largeur d’impulsion), ce qui lui confère un intérêt exploratoire. Le second convertisseur consiste en une alimentation résonante haute tension et haute fréquence permettant l’éviction du transformateur élévateur, et mettant en oeuvre des interrupteurs au nitrure de gallium (GaN) afin d’atteindre une fréquence de fonctionnement supérieure au mega-Hertz avec un faible niveau de pertes. / DBD devices are widely used in industrial applications. 150 years ago, they were only employed in ozoners for water decontamination. In recent decades, the progress of knowledge and technology allowed to use them in many other applications like surface treatment, medical applications and light emission. Actually, these devices are supplied with an electrical source which parameters can strongly impact the discharge behaviour. An important part of this work comes within the framework of the development of an atmospheric pressure surface treatment involving DBDs. The issue of the influence of the generator's electrical parameters on the treatment speed is discussed. In particular, this work focuses on the merits of a rectangular shaped current source concerning the behavior of an atmospheric pressure discharge in nitrogen ; the problems related to the design and the fabrication of such a converter are highlighted. The design of the high voltage transformer is then described in detail since its lumped elements play an important role as they can strongly limit the power transfer between the electrical source and the DBD device. A second aspect of this work is to establish the interests of two particular power converters. The first one is a resonant converter operating in a discontinuous conduction mode ; its merits is to exhibit three degrees of freedom (input voltage, frequency, current pulse width) instead of two, which is a tremendous asset for exploring purposes. The second one is a high-frequency resonant converter where a resonant inductance and the DBD device structural capacitances are used instead of a high voltage transformer to perform the voltage amplification, which circumvents the issue related to the transformer parasitic elements. This converter is based on GaN HEMT switches in order to reach a low semiconductor losses level and a fairly high operating frequency (above the mega-Hertz).
468

Latenciação de hidroximetilnitrofural com derivados de quitosana, potencialmente ativos em leishmaniose e doença de Chagas / Latentiation of hidroximetilnitrofural derivative chitosan, potentially active in leishmaniasis and Chagas disease

Katia Solange Cardoso Rodrigues dos Santos 16 May 2005 (has links)
Leishmaniose e doença de Chagas são parasitoses endêmicas causadas, respectivamente, pelos protozoários Leishmania spp. e Trypanosoma cruzi. Ante à escassez de quimioterápicos, à elevada toxicidade dos fármacos disponíveis e à baixa eficácia destes no combate às formas intracelulares, replicantes, dos parasitos há necessidade de buscar novas alternativas quimioterápicas. A atividade tripanomicida do hidroximetilnitrofural, base de Mannich do nitrofural, já era conhecida. O presente trabalho mostra que este derivado também apresenta atividade leishmanicida, quando ensaiado em formas promastigotas de L. amazonensis, L. chagasi e L. baziliensis. Com o objetivo de obter pró-fármacos potencialmente ativos em doença de Chagas e leishmanioses visceral e mucocutânea, planejaram-se e foram sintetizados derivados hidrossolúveis de hidroximetilnitrofural e quitosana, polissacarídeo que apresenta, também, atividade imunomoduladora. Para a aplicação tópica em leishmaniose cutânea sintetizaram-se membranas de quitosana ligada ao hidroximetilnitrofural. Membranas de quitosana copolimerizadas com enxertos de ácido acrílico e metacrilato de hidroxietila foram sintetizadas e avaliadas quanto à biocompatibilidade - trombogenicidade, citotoxicidade e potencial hemolítico. Aquelas com maior teor em metacrilato de hidroxietila não se mostraram citotóxicas, tampouco hemolíticas; aquelas com maior proporção em ácido acrílico, por sua vez, apresentaram excelentes características de intumescimento, mas certo grau de citotoxicidade e hemólise, possivelmente devido à presença de monômeros que não reagiram no material. A ligação do hidroximetilnitrofural à quitosana, por meio de espaçante succínico, produziu prófármaco com propriedades filmogênicas para a aplicação tópica. Os derivados obtidos pró-fármacos e transportadores (quitosanas modificadas) - foram analisados no infravermelho, por ressonância magnética nuclear (RMN 1H e RMN 13C) e por análise térmica - OMTA, TG, OSC. Ensaios de atividade tripanomicida e leishmanicida dos pró-fármacos poliméricos e membranas serão posteriormente efetuados. / Leishmaniasis and Chagas\' disease are endemic parasitosis provoked by the protozoa Leishmania spp and Trypanosoma cruzi, respectively. Due to the scarce chemotherapy, to the high toxicity of the available drugs and to their low effectiveness, mainly in the treatment of intracellular replicant forms of those parasites, the search for new chemotherapeutic alternatives is extremely important. Hydroxymethylnitrofurazone, a nitrofurazone Mannich basis, has proven to be active against trypanomicide before and its activity in cultures of L. amazonensis, L. chagasi and L. braziliensis promastigotes was determined in this work. With the purpose of obtaining prodrugs potentially active in Chagas\' disease and visceral and mucocutaneous leishmaniases, hydrosoluble hydroxymethylnitrofurazone prodrugs have been designed and synthesized using chitosan, a polysaccharide showing immunomudulatory activity, as the carrier. Membranes from chitosan linked with hydroxymethylnitrofurazone have been synthesized for topical administration in cutaneous leishmaniasis. Membranes were obtained by graft copolymerization of hydroxyethy/methacrylate and acrylic acid onto chitosan and their biocompatibility - trombogenicity, citotoxicity and hemolysis potential - was evaluated. Those membranes with higher content of hydroxyethylmethacrylate showed to be neither cytotoxic nor hemolytic; those with higher content of acrylic acid showed good swelling properties, although a certain level of cytotoxicity and haemolysis has been detected, due to the presence of non-reacted monomers. The linkage of hydroxymethylnitrofurazone to chitosan by a succinyl spacer group led to a prodrug with filmogenic properties for topic administration. The derivatives obtained - prodrugs and carriers (modified chitosans) - were analyzed by infrared, nuclear magnetic resonance (1H NMR and 13C NMR) and by thermal analysis - DMTA, TG and DSC. Tests of trypanomicide and leishmanicide activity with polymer prodrugs and membranes will be further developed.
469

Caracterização da infecção por tripanossomatídeos (Protozoa: Kinetoplastida) presentes em três espécies de cascudo (Pisces: Loricariidae) do Rio Mogi-Guaçu, SP / Characterization of infection by Tripanossomatídeos (Protozoa: Kinetoplastida) present three species of armored catfish (Pisces: Loricariidae) from Mogi-Guaçu river, SP

Molina, Julia Pereira, 1985- 17 August 2018 (has links)
Orientador: Marlene Tiduko Ueta / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-17T04:30:52Z (GMT). No. of bitstreams: 1 Molina_JuliaPereira_M.pdf: 1442066 bytes, checksum: e8ad2a162950fbe267341b74c08ad0f7 (MD5) Previous issue date: 2010 / Resumo: Os tripanossomas já foram reportados em diversas espécies de peixes de água salgada e doce, sendo a maioria das espécies descritas com base nas características morfológicas. Tripanossomas parasitos de peixes são heteroxenos e são transmitidos por hirudíneos. Este trabalho tem como objetivos caracterizar a prevalência e densidade da infecção por Trypanosoma sp. presentes no sangue de três espécies de cascudos do rio Mogi Guaçu, Cachoeira de Emas, município de Pirassununga, SP e caracterizar morfologicamente e por técnicas moleculares os exemplares de Trypanosoma encontrados no sangue dos cascudos. Entre fevereiro de 2008 e fevereiro de 2009 foram coletados 256 exemplares de cascudos sendo 60 Hypostomus albopunctatus, 100 Hypostomus regani e 96 Hypostomus strigaticeps. O sangue foi coletado por punção cardíaca e alíquotas de 8?l foram retiradas para confecção de esfregaço em camada delgada, que foram fixados em metanol e corados por Giemsa, para a determinação da positividade e densidade dos tripanossomas. Após a biometria e coleta do sangue os peixes foram marcados e metade foi acondicionada em um tanque de criação do CEPTA/ ICMBIO para verificação da manutenção da infecção e o restante foi devolvido ao rio. A prevalência geral de tripanossomas foi de 47,6 % e densidade média geral de 0,75 parasitas/ µl de sangue. A prevalência ao longo do ano apresentou diferenças significativas apenas para Hypostomus regani (p=0,0054) e Hypostomus strigaticeps (p=0,0007). A densidade média de parasitas não apresentou diferenças significativas entre as três espécies de peixes analisados, assim como a variação mensal da densidade por espécie de peixes. Hirudíneos do gênero Placobdella sp. foram coletados da superfície do corpo e da boca de H regani e H. strigaticeps para extração do DNA, os oligonucleotídeos utilizados (S-1842 e S-1843) amplificaram um fragmento de 1000pb do gene 18S rRNA dos tripanossomas isolados de hirudíneos coletados em H regani e H. strigaticeps. Dos 19 peixes recapturados após dois meses apenas três se mantiveram positivos. Foram medidos 255 tripanossomas sendo 66 de H. albopunctatus, 64 de H. regani e 95 de H. strigaticeps e os valores foram comparados com os de outras espécies de tripanossomas encontradas em peixes do gênero Hypostomus. Os parasitas encontrados nas três espécies de peixes apresentaram características morfológicas semelhantes. Foi estabelecida a frequência de ocorrência de acordo com a variação do comprimento do corpo para evidência de pleomorfismo. Os dados morfológicos mostram que Trypanosoma sp.1 e Trypanosoma sp.2 podem ser considerados de espécies diferentes; as análises evidenciaram a presença de pleomorfismo nos tripanossomas encontrados nas três espécies de peixes. / Abstract: Trypanosomes have been reported in several species of fish that inhabit salt and fresh waters. The majority of these protozoan species are described based on morphologic features. The parasites are heteroxenic and are transmitted by leeches. This work aims to characterize the prevalence and density of infection by Trypanosoma sp. present in the blood of three species of armored catfish collected from Mogi Guaçu river (Cachoeira das Emas, Pirassununga city, SP) and characterize morphologically and by molecular techniques the trypanosomes found in the blood of catfish. Between february 2008 and february 2009, 256 specimens of armored catfish were collected, being 60 Hypostomus albopunctatus, 100 Hypostomus regain, and 96 Hypostomus strigaticeps. The blood was collected by cardiac puncture and a sample of 8µl was removed to realize blood smears on microscope slides. The slides were fixed in methanol and stained with giemsa for posterior analysis on light microscopy for determination of positive presence and density of trypanosomas. After biometric analysis and blood collection fish were marked half of the fish marked were maintened in a tank of CEPTA/ ICMBIO for future verification of the infeccion maintence and the other half were retorned to the river. It was found a prevalence of 47,6% and the average density of 0,75 parasitas/µl of blood. The prevalence during the year presented significative differences only for Hypostomus regani (p=0,0054) e Hypostomus strigaticeps (p=0,0007). The average density of parasites showed no significant differences among the three fish species analyzed and the monthly variation of density per species of fish. Also, leeches of the genus Placobdella sp. were collected from the surface of the body and mouth of armored catfish for DNA extraction. The primers used (S-1842 and S- 1843) amplified a 1000bp fragment of the 18S rRNA gene of trypanosomes isolated from leeches collected in H regani and H. strigaticeps. Of the 19 fish recaptured after two months only three remained positive. Therein, 255 trypanosomes were measured being 66 H. albopunctatus, 64 H. regani and 95 H. strigaticeps and values were compared with those of other parasite species found in different species of fish. The parasites found in the three species of fish presented similar morphological characteristics. The frequency of occurrence was established according to the variation in body length as evidence of pleomorphism. Nevertheless morphological data show that Trypanosoma sp.1 and Trypanosoma p.2 can be considered distinct species, the analysis revealed the presence of pleomorphism in trypanosomes found in the three species of fish. / Mestrado / Parasitologia / Mestre em Parasitologia
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Investigação sobre a ocorrencia de eaquistossomose mansonica medular autoctonse em uma região com baixa endemicidade (Campinas - SP) / Study on the occurence of spinal cord neuroschistosomiasis mansoni in a low prevalence area (Campinas, SP, Brazil)

Freitas, Andre Ricardo Ribas 13 August 2018 (has links)
Orientador: Luiz Jacintho Silva / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-13T10:32:11Z (GMT). No. of bitstreams: 1 Freitas_AndreRicardoRibas_M.pdf: 3288382 bytes, checksum: 1e4d10a420b3969b93fb46828328259d (MD5) Previous issue date: 2007 / Resumo: Os programas de controle da esquistossomose têm obtido relativo sucesso ao controlar a morbidade relacionada a altas cargas parasitárias desta doença, sem, no entanto, diminuir a área de transmissão no Brasil. Como a neuroesquistossomose medular á uma forma grave de esquistossomose não relacionada a altas cargas parasitárias existe risco teórico de ocorrer em áreas de baixa endemicidade. O objetivo deste estudo foi estudar a ocorrência da NE (neuroesquistossomose) medular em uma região de baixa endemicidade, região de Campinas, estado de São Paulo. Foi feito um estudo retrospectivo, descritivo de base hospitalar com busca ativa em múltiplas fontes de informação. Utilizou-se como base os dois maiores hospitais públicos da região de Campinas. Os pacientes com diagnóstico de NE medular tiveram seus diagnósticos ratificados por critérios padronizados e baseados em quadro clínico típico, comprovação da infecção por Schistosoma mansoni e exclusão de outras causas de mielopatia. Os pacientes foram classificados como autóctones, importados, sem informação e indeterminado. Após esta classificação os dados clínicos e epidemiológicos foram analisados. Foram identificados 27 pacientes com NE medular dos quais 19 (85,2%) homens e 4 (14,8%) mulheres, as idades no momento do diagnóstico foram de 13 a 57 anos (média=31,2; desvio padrão=12,8 e mediana=29). Os pacientes foram classificados quanto ao local provável de infecção da seguinte forma: 14(51,9%) autóctones, 11(40,7%) importados e 2(7,4%) sem informações, não houve paciente classificado como indeterminado. Todos os pacientes importados se infectaram em municípios de áreas de alta endemicidade. A clínica deste grupo de pacientes não foi diferente do encontrado na literatura, nem foi diferente quando comparados os pacientes autóctones com os importados. Houve uma demora média de 70,6 dias (mediana=19; dp=166,9) entre a primeira consulta e o diagnóstico. A demora foi em média 88,1 dias maior entre os pacientes autóctones (média=112 dias; mediana=26; dp=224,3) do que entre os importados (média=23,9 dias; mediana=9; dp=42,7) e esta diferença foi estatisticamente significativa p=0,0247. A sensibilidade da sorologia foi de 87,5%, da imunologia de LCR 93,8% e dos exames parasitológicos foi de 40,0%. Apenas 4 (14,8%) tiveram evolução com melhora completa, 6 (22,2%) apresentaram melhora sem limitações, 13 (48,1%) apresentaram melhora com limitações e 4 (14,8%) não apresentaram melhora alguma. Apenas 11 pacientes (41%) com NE medular incluídos neste estudo estavam notificados à vigilância epidemiológica e a informação de que estes pacientes tinham quadros neurológicos não constavam no banco de informações do SINAN. Concluiu-se que a NE medular ocorre mesmo em áreas de baixa endemicidade e nestas áreas existe uma demora muito grande no diagnóstico, principalmente entre os pacientes autóctones. O exame de fezes não se mostrou sensível para diagnóstico e rastreamento de pacientes vulneráveis a NE medular por se tratarem de pacientes com baixas cargas parasitárias. Portanto métodos diagnósticos mais sensíveis deveriam ser utilizados pelos programas de controle de esquistossomose / Abstract: Programs for schistosomiasis control have enjoyed relative success in controlling death associated to high parasitary loads for this illness, without, however, decreasing the area of transmission in Brazil. Since spinal neuroschistosomiasis is a grave form of neuroschistosomiasis unrelated to high parasitary loads, there is a theoretical risk of its occurrence even when not in a particularly endemic area. The goal of this study was to study the occurrence of spinal NE (neuroschistosomiasis) in a non-endemic area, the region of Campinas, in the Sate of São Paulo. A retrospective, descriptive, hospital-based study was carried, with information actively sought after from various sources of information. The two largest public hospitals in the region of Campinas were used as bases. The patients diagnosed with spinal NE had their diagnoses ratified according to standard criteria and based on typical clinical status, proof of infection by Schistosoma mansoni and the exclusion of other causes for myelopathy. Patients were classified as autochthonous, imported, without information and undetermined. After this classification, the clinical and epidemiological data were analyzed. A total of 27 patients with spinal NE were identified, of which 19 (85.2%) were men and 4 (14.8%) women. The ages on diagnosis ranged from 13 to 57 (average=31.2; standard deviation=12.8 and median=29). The patients were classified as to their probable location of infection the following way: 14(51.9%) autochthonous, 11(40.7%) imported and 2(7.4%) without information. No patients were deemed undetermined. All imported patients were infected in municipalities located in highly endemic areas. Clinical evaluation of this group of patients was no different from that found in the literature, nor was it different when autochthonous patients were compared to imported patients. There was an average period of 70.6 days (median=19; sd=166.9) between the first consultation and diagnosis. The period was on average 88.1 days longer for autochthonous patients (average=112 days; median=26; sd=224.3) than for imported patients (average=23.9 days; median=9; sd=42.7) and this difference was statistically significant p=0.0247. Sensitivity of the serology was 87.5%, LCR immunology 93.8% and for parasitological exams it was 40.0%. Only 4 (14.8%) had evolution with complete recovery, 6 (22.2%) presented improvement without limitations, 13 (48.1%) presented improvement with limitations and 4 (14.8%) did not present improvement. Only 11 patients (41%) with spinal NE included in the study had been notified to epidemiological surveillance and the information that these patients had neurological patterns of symptoms was not present in the SINAN data base. It can be concluded that spinal NE occurs even in non-endemic areas and that diagnosis in such locations can take excessively long, especially for autochthonous patients. Feces exams were not shown to be sensitive for diagnosis and tracing of patients vulnerable to spinal NE since such patients presented low parasitary loads. Therefore more sensitive means of diagnosis should be utilized by schistosomiasis control programs / Mestrado / Ciencias Biomedicas / Mestre em Clinica Medica

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