• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 61
  • 18
  • 10
  • 9
  • 5
  • 2
  • 2
  • Tagged with
  • 112
  • 11
  • 9
  • 8
  • 8
  • 7
  • 7
  • 6
  • 6
  • 6
  • 6
  • 6
  • 6
  • 6
  • 6
  • 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.
51

Desenvolvimento de protocolo de sincronização da onda folicular e determinação do momento ideal para indução da ovulação na espécie equina / Development of a follicular wave synchronization protocol and establishment of the ideal time to ovulation induction in mares

Ana Paula Reway 25 January 2017 (has links)
Foram realizados cinco experimentos com o objetivo de sincronização do estro e indução da ovulação em tempo fixo em éguas. Experimento I: avaliou a eficácia de um novo protocolo hormonal para a sincronização do estro, sendo realizado durante o período transicional em éguas cujo status reprodutivo era desconhecido. Experimento II: foi delineado para determinar o momento ideal para retirada dispositivo intravaginal de progesterona (DIP), sendo o dispositivo retirado no dia 7, 8 ou 9 do protocolo de tratamento hormonal. Experimento III: testou se a eficiência do protocolo é dependente da fase do ciclo estral da égua e definiu o melhor momento para indução da ovulação. Experimentos IV e V: as éguas foram submetidas ao protocolo completo de sincronização da onda folicular e indução da ovulação em diferentes fases do ciclo estral ou com status reprodutivo conhecido. A hipótese testada foi de que a sincronização do estro e indução da ovulação, com o uso do DIP de 1,44g provoca a supressão do crescimento folicular e através da indução da ovulação, com hCG e GnRH, promove a ovulação dentro de 42 ± 6 horas de no mínimo 75% dos animais. Para isso, os efeitos das prostaglandinas e progestágenos foram avaliados quanto à capacidade de sincronizar a onda de crescimento folicular. Um novo tratamento para induzir a ovulação em tempo fixo foi testado com uma combinação de GnRH e hCG em dois momentos estratégicos (D10 e D12) visando maximizar o número de éguas ovuladas. O protocolo com administração de prostaglandina no D0, D6 e D8 juntamente com a colocação do DIP mantido durante 8 dias (D0 ao D7) demonstrou ser eficaz para suprimir a taxa de crescimento folicular em éguas cíclicas. Nas éguas submetidas a este protocolo as ovulações que ocorreram naturalmente se concentraram entre os dias 10 e 13 do tratamento. Foi testada a eficiência da indução da ovulação no D10 e D12. Na maioria dos animais tratados, o folículo pré-ovulatório foi responsivo à combinação de GnRH e hCG promovendo o sucesso da indução da ovulação. A eficiência do protocolo hormonal testado para sincronização do estro e da ovulação foi de 76,73%, sustentando a hipótese deste estudo. Novos estudos devem ser realizados em um maior número de animais para possíveis adequações na terapia hormonal e verificação do resultado em um grande número experimental de animais. / Five experiments were conducted with the objective of estrus synchronization and fixed time ovulation induction in mares. Experiment I: evaluated the efficacy of a new hormonal protocol for estrus synchronization in mares whose reproductive status was unknown during the transitional period. Experiment II: was designed to determine the best time to remove the P4 intravaginal device (PID). The device was removed on day 7, 8 or 9 of the hormonal treatment protocol. Experiment III: tested if protocol efficiency depends on the stage of mares estrus cycle and indicated the best time for hormonal induction of ovulation. Experiments IV and V: mares were submitted to the full protocol of follicular wave synchronization and ovulation induction at different stages of estrus cycle or at known reproductive status. The tested hypothesis was that the estrus synchronization and induction of ovulation, using an PID of 1.44g, causes suppression of follicular growth, and ovulation induction using hCG and GnRH promote ovulation within 42 ± 6 hours of at least 75% of treated animals. The effect of prostaglandin and progestagens at specific times were evaluated for the ability to synchronize follicular wave. A new treatment to induce fixed time ovulation was tested with GnRH and hCG combination in two strategic moments (D10 and D12) to maximize the number of ovulated mares. Administration of prostaglandin at D0, D6 and D8 together with PID maintained for 8 days (D0 to D7) proved to be effective to suppress follicular growth during reproductive period. In mares submitted to this protocol, ovulation occurred naturally and concentrated between D10 and D13. The ovulation induction efficiency was tested at D10 and D12. Most of the animals had preovulatory follicle responsiveness to GnRH and hCG, promoting the success of ovulation induction. The efficiency of the tested synchronization of estrus and ovulation induction protocol was 76.73% and supported the hypothesis of this study. Further studies should be performed on a larger number of animals for possible adjustments in hormonal therapy and verification of the result in a large number of animals.
52

Coagulation, oncotic and haemodilutional effects of a third generation hydroxyethyl starch (130/0.4) in ponies

Viljoen, Adrienne January 2014 (has links)
This dissertation describes the effects of tetrastarch (130/0.4) on serum colloid osmotic pressure and thromboelastography variables in healthy pony mares. Additional variables assessed during this study included markers of haemodilution (PCV, TS) and serum creatinine and bile acid concentrations. Six clinically healthy Nooitgedacht pony mares were utilized in a crossover study design. Tetrastarch (130/0.4) was administered at 10, 20 and 40 ml/kg bwt to each mare in a random sequence with a two week washout period between each of the treatments. Packed cell volume (PCV), plasma total solids (TS), serum colloid osmotic pressure (COP), and platelet count were measured and thromboelastography (TEG) was performed before treatment (baseline), immediately after infusion (time 0), and 1, 6, 12, 24, 48, and 96 h after tetrastarch infusion. All TEG variables remained within reference range in all treatment groups. Administration of tetrastarch at 40 ml/kg bwt resulted in a prolonged K-time at 6 h post-infusion, and decreased maximum amplitude at 0, 1, 6, 24 and 48 h post-infusion compared to baseline. Administration of tetrastarch increased mean COP values above baseline in all three treatment groups, persisting to 24, 6 and 48 h after treatment with 10, 20 and 40 ml/kg of tetrastarch respectively. This study concluded that, although values remained within established reference ranges, the administration of tetrastarch (130/0.4) at 40 ml/kg bwt is more likely to induce changes in TEG variables than doses of 20 ml/kg or less. Tetrastarch increased COP in healthy horses at all evaluated dose rates. / Dissertation (MMedVet)--University of Pretoria, 2014. / gm2014 / Companion Animal Clinical Studies / unrestricted
53

Técnicas de detección radar en escenarios marítimos heterogéneos

Gálvez, Nélida B. 04 May 2018 (has links)
Durante las últimas décadas se ha realizado mucho esfuerzo para encontrar soluciones eficientes al problema de detección de los radares marítimos modernos. La probabilidad de detección de objetos de interés depende altamente de los esquemas de detección seleccionados y sus distribuciones de clutter y señal. Se han desarrollado diferentes estrategias de detección con el objetivo de discriminar el retorno marino de la señal de interés. Estas estrategias establecen un umbral que depende de la potencia del retorno marino local basada en un test de hipótesis para una determinada falsa alarma. En esta tesis, se presentan algunos detectores radar con el propósito de encontrar soluciones eficientes al problema de discriminar entre los objetos de interés y el ambiente marino, especialmente para el caso de condiciones no homogéneas que usualmente acaecen en el escenario marino. Con ese propósito, se describen algunos modelos del entorno marino por medio de sus distribuciones estadísticas para baja y alta resolución. Por ejemplo, para el caso de baja resolución y ángulos de incidencia altos, el clutter generalmente se modela por medio de la distribución Gaussiana. Sin embargo, para el caso de radares modernos de alta resolución, donde las celdas de rango son pequeñas con muy pocos dispersores, el retorno radar se aleja de las distribuciones Gaussianas y el ambiente marino se representa muy bien mediante distribuciones de cola larga, tales como las distribuciones Weibull y K. En este trabajo, se discuten los principios básicos de la detección radar. Se realiza una descripción detallada de algunos esquemas clásicos, tales como el detector de Neyman Pearson, el GLRT, y algunos esquemas de detección, como el CA CFAR, el GO CFAR, el SO CFAR, el OS CFAR y el detector propuesto por [60] . Teniendo en cuenta que la detección radar se puede interpretar como un problema de reconocimiento de patrones, las redes neuronales son apropiadas para tratarlo, por consiguiente, se consideraron algunas soluciones por medio de varios algoritmos tales como el ANN CFAR, el CANN CFAR y el NNCAOS CFAR. Finalmente, se presenta un nuevo detector radar en el contexto de los sistemas no-coherentes que operan en ambientes marinos no homogéneos. Se considera el caso especial de un radar de alta resolución con un ángulo de incidencia bajo, que funciona en condiciones de mar adversas. El esquema de detección que se plantea, se basa en la propuesta de un nuevo modelo del ambiente marino. Los objetivos de diseño de esta distribución fueron introducir grados de libertad adicionales (parámetros) con respecto a la distribución K para modelar los casos de colas pesadas y también obtener un detector en forma cerrada que aproxime la propiedad CFAR cuando trabaja en condiciones extremas. / During the last decades much effort has been done to find efficient solutions to the problem of detection for modern maritime radar. The probability of detection of a target highly depends on the selected detection scheme and its signal and clutter distributions. Different detection strategies have been developed in order to discriminate the clutter from the signal of interest. These detection strategies set a threshold that depends on the local clutter power based on a hypothesis test for an expected false alarm rate. In this thesis, several radar detectors were introduced with the purpose of finding efficient solutions to the problem of discriminating between targets and the clutter environment, especially for the case of non-homogeneous situations that usually happen in the sea scenario. To that purpose some clutter models are described by means of their statistical distributions for low and high resolution. For example, for the case of low resolution and high grazing angles the clutter is generally modeled by means of the Gaussian distribution. However, for the case of the modern high resolution radars, where the range cells are small with only few scatterers, the clutter models depart from the Gaussian distributions and the sea environments are well represented by means of long tailed distributions, like the Weibull and the K. In this work, the basic radar detection principles are discussed. A detailed description of some classic detection schemes are given, like the Neyman Pearson Detector, the GLRT, and some CFAR detection schemes, like the CA CFAR, the GO CFAR, the SO CFAR, the OS CFAR and the detector proposed by [60] . Considering that the radar detection may be interpreted as a pattern recognition, the Neural Networks are suitable to deal with the problem. Some solutions were considered by means of several algorithms like the specialized ANN CFAR, the CANN CFAR and the NNCAOS CFAR. Finally, a new radar detector in the context of non-coherent radar systems operating under non-homogeneous sea clutter and the special case of a high resolution radar at low grazing angles under adverse sea conditions, is presented. The novel detection scheme is based on a new clutter distribution model. The design objectives of this clutter distribution were to introduce additional degrees of freedom (parameters) with respect to the K distribution to model heavy tailed cases and also to obtain a closed-form detector that approximates the CFAR property when working under very stringent detection conditions.
54

Diversité des virus dans les lacs de fonte de pergélisol au nord du Québec

Lévesque, Alice 22 May 2018 (has links)
Les mares et lacs de fonte de pergélisol (ou lac de thermokarst) sont désormais parmi les écosystèmes d’eau douce les plus communs en région arctique. Il existe deux types de lac de thermokarst en fonction de la composition du sol dans lequel celui-ci se forme (palse, lithalse). Ces lacs constituent des milieux complexes présentant une activité microbienne élevée qui produit une grande quantité de gaz à effet de serre. D’un point de vue écologique, il est essentiel d’approfondir nos connaissances sur les forces contrôlant cette activité microbienne. En général, les virus participent à divers processus écologiques essentiels notamment en influençant le recyclage des nutriments, les cycles biogéochimiques et la dynamique des populations microbiennes. Par contre, très peu d’études se sont intéressées aux populations virales dans les lacs de fonte. Ainsi, les objectifs principaux de ce projet sont (1) d’établir la diversité virale dans deux types de lacs de thermokarst en visant deux familles de virus en particulier (myovirus, chlorovirus), et (2) d’isoler un cyanophage à partir de ces milieux. Une approche par PCR a permis d’obtenir la composition des assemblages viraux et de conclure que ces derniers variaient en fonction de la distribution de leurs hôtes, qui eux étaient influencés par les paramètres environnementaux. De plus, deux nouveaux cyanophages appartenant à la famille des Myoviridae ont également été isolés d’un lac subarctique et leur génome séquencé. Des analyses génomiques ont démontré la présence de deux gènes auxiliaires métaboliques, suggérant des évènements de transferts horizontaux entre les virus et leur hôte. Bref, cette étude apporte de nouvelles connaissances concernant l’écologie et la biologie des communautés virales en milieu subarctique. / Arctic regions are undergoing rapid changes due to global warming. Permafrost thawing and erosion is accelerating, creating small and shallow lakes, called thermokarst lakes, that are now widespread in Arctic landscapes. Thaw lakes can be classified in two groups depending on the landscape (palsa, lithalsa), and this has a great impact on their limnological properties. These freshwater ecosystems are highly stratified and harbour microbial assemblages that are important contributors of greenhouse gases to the atmosphere. In general, the two major groups involved in the top-down control of microbial populations are either grazers or viruses. Here, we focused our study on viral communities, as it is now widely recognized that viruses are key components in all aquatic ecosystems. Although they have a large impact on nutrient cycles and host evolution and dynamics, viruses in high latitudes freshwater ecosystems remain poorly characterized. The aims of this study were: (1) to determine viral diversity in different types of thermokarst lakes by targeting specific families of viruses; and (2) to isolate a cyanophage from a subarctic lake. Using a PCR-based approach followed by high-throughput sequencing, we characterized the viral community composition in contrasting subarctic waterbodies. Comparisons suggested that viral diversity was primarily influenced by landscape type, which affects the host communities. Also, we isolated and sequenced the genome of two novel cyanomyoviruses. Analysis of these genomes revealed the presence of two auxiliary metabolic genes, suggesting horizontal gene transfer events between viruses and hosts. Overall, this study sheds light into the dynamics and the composition of viral communities in high-latitude freshwater environments.
55

Émission de composés organiques volatils par la photochimie de la matière organique dans les mares nordiques

Fillion, Daniel 17 October 2023 (has links)
Thèse ou mémoire avec insertion d'articles / Titre de l'écran-titre (visionné le 12 octobre 2023) / Le pergélisol, le sol gelé pendant au moins deux années consécutives, contient presque deux fois plus de carbone que l'atmosphère. Le réchauffement climatique a suffisamment accéléré son dégel pour mobiliser une quantité considérable de matière organique dissoute (MOD) vers l'hydrosphère, dont les mares font partie. La MOD peut alors être dégradée en divers sous-produits par la radiation solaire. Vers la phase gazeuse, cela implique la production de CO₂, mais également de composés organiques volatils (COVs) qui ont été peu étudiés en zones nordiques. Pourtant, les COVs ont des impacts importants sur la chimie de l'atmosphère. L'objectif principal de ce mémoire est d'identifier les molécules produites vers la phase gazeuse par photochimie et de quantifier leurs flux. Pour y arriver, un montage de photochimie a été construit, testé puis interfacé à deux détecteurs pour des analyses en temps réel : un spectromètre de masse Orbitrap et un spectromètre de masse Vocus. Des mares de thermokarst, formées par le dégel du pergélisol riche en glace, près des villages d'Umiujaq et de Whapmagoostui-Kuujjuarapik, au Nunavik, ont été sélectionnées pour des campagnes d'échantillonnage aux étés 2021 et 2022. Des échantillons de la colonne d'eau et des zones ripariennes ont été prélevés. Les résultats montrent la photo-production rapide de 35 à 59 COVs lorsque les échantillons d'eau contenant de la MOD sont soumis à la radiation. Les résultats suggèrent que la qualité de la MOD est un facteur important qui contrôle la photo-production de COVs. Quantitativement, ces émissions correspondent à des flux nets de carbone entre 1.93 et 9.47 μmol C m⁻² d⁻¹ vers l'atmosphère. Ces valeurs sont petites en comparaison aux flux estimés de CO₂ et de CH₄ qui sont émis par les mares subarctiques. Malgré une contribution négligeable au cycle du carbone arctique, les COVs représentent néanmoins un flux de molécules réactives qui pourraient affecter la chimie atmosphérique. / Permafrost, the soil frozen for a minimum of two consecutive years, stores almost twice the amount of carbon found in the atmosphere. Climate warming has accelerated its thaw to a point where a considerable quantity of dissolved organic matter (DOM) is being mobilized toward the surface where it enters the hydrosphere, like lakes. DOM can be photo-degraded into various products by sunlight. In the gas phase, this includes CO₂ and volatile organic compounds (VOCs) that are poorly studied in Arctic environments. Yet, they affect the chemistry of the atmosphere. The main objective of this master projet is to identify the VOCs emitted in the gas-phase by photochemistry as well as to quantify their fluxes. To achieve this, a photochemistry set-up has been constructed and tested. Then, it has been interfaced with two detectors for real-time analysis: an Orbitrap mass spectrometer and a Vocus mass spectrometer. Thermokarst ponds, formed by the thawing of ice-rich permafrost, near the villages of Umiujaq and Whapmagoostui-Kuujjuarapik, Nunavik, were selected for field campaigns during summers 2021 and 2022. Samples from the water column and the riparian zones were taken. Results show the rapid photo-production of between 35 and 59 VOCs when dissolved organic matter (DOM) water samples are exposed to radiation. Results show that the quality of DOM is an important factor that controls VOCs photoproduction. In terms of quantification, these emissions correspond to net carbon fluxes between 1.93 et 9.47 μmol C m⁻² d⁻¹ toward the atmosphere. These values are small when compared to estimated fluxes of CO₂ and CH₄ by subarctic ponds. Despite their negligeable contribution to the Arctic carbon cycle, VOCs represent a flux of reactive molecules that could affect the atmospheric chemistry.
56

Perfil bioquímico sérico de éguas gestantes e não gestantes das raças brasileiro de hipismo e bretão /

Campelo, José Arnodson de Sousa. January 2008 (has links)
Orientador: José Corrêa de Lacerda Neto / Banca: Luiz Francisco Prata / Banca: Gilson Helio Toniollo / Banca: Adriana Alonso Novais / Banca: Fabiana Garcia Christovão / Resumo: Objetivou-se a determinação das concentrações séricas de aspartato aminotransferase (AST), fosfatase alcalina, creatinina, uréia, fibrinogênio, proteína total, albumina, globulinas, bilirrubinas direta, indireta e total, sódio (Na+), potássio (K+), cloro (Cl-), cálcio ionizado (Ca++) e fósforo (P) de éguas das raças Brasileiro de Hipismo (BH) e Bretão não prenhes e prenhes, em diferentes períodos de gestação. Foram efetuadas colheitas de sangue das éguas vazias e prenhes de acordo com a raça e o período de gestação: Inicial (25 a 110 dias), intermediário (111 a 210 dias) e final (211 a 340 dias). Os íons de Na + e K+ foram determinados por meio de um equipamento seletor de íons. Para mensuração do fibrinogênio utilizou-se um coagulômetro. As demais variáveis foram dosadas através de um sistema de reagentes comerciais. As éguas não prenhes foram observadas diferenças entre as raças BH e Bretão para as variáveis albumina e bilirrubina indireta, enquanto nas prenhes ocorreram diferenças entre raças no decorrer da gestação para fosfatase alcalina, creatinina, fibrinogênio, proteína total, albumina, globulinas, bilirrubinas direta, indireta e totais, sódio, potássio, cloro, cálcio e fósforo. Detectou-se, no decorrer da prenhez, tendência a elevação dos valores de fibrinogênio e globulinas. As concentrações séricas de creatinina, fosfatase alcalina proteína total, Cl- e K+ se mantiveram praticamente inalterados durante a gestação. Os valores de AST, albumina, bilirrubinas direta, indireta e total, Na+ e Ca++ mostraram tendência à diminuição, enquanto as concentrações de uréia e de P flutuaram sem um padrão definido durante a gestação. As variações observadas nos parâmetros estudados refletem alterações no metabolismo e na homeostasia das raças BH e Bretão durante a gestação. / Abstract: The purpose of this study was to determine serum aspartate amino tranferase (AST), alkaline phosphatase, creatinine, urea, fibrinogen, total proteins, albumin, globulins, conjugated, unconjugated and total bilirubin, sodium (Na+), potassium (K+), chloride (Cl-), calcium (Ca++) and phosphorus (P) of pregnant and nonpregnant mares of Brazilian Sport Horse (BH) and Breton breeds, in different pregnancy moments. Blood samples were obtained from pregnant and nonpregnant mares of both breeds, divided into three groups as follows: initial group - 25 to 110 days of pregnancy; intermediary group - 111 to 210 days of pregnancy; final group - 221 to 340 days of pregnancy. Na+ and K+ were determined by ionic selection. Fibrinogen was measured by coagulometry. The other values were obtained by a commercial reaction system. Comparing BH and Breton breeds, nonpregnant mares presented different serum concentrations of albumin and unconjugated bilirubin. Pregnant mares presented differences between the breeds when compared serum alkaline phosphatase, creatinine, fibrinogen, total proteins, albumin, globulins, conjugated, unconjugated and total bilirubin, Na+, K+, Cl-, Ca++ and P. During the pregnancy it was observed a tendency to increase of serum fibrinogen and globulins however serum creatinine, alkaline phosphatase, total proteins, Cl- and K+ have not changed. Serum AST, albumin, conjugated, unconjugated and total bilirubin, Na+ and Ca++ showed a tendency to decrease while serum urea and P values remained relatively constant during the pregnancy. Changes observed in the concentrations of the studied parameters showed metabolic and homeostatic differences between BH and Breton mares during pregnancy. / Doutor
57

Avaliação do equilíbrio oxidativo na gestação e perinatologia equina / Evaluation of oxidative balance in gestation and equine perinatology

Souza, Danilo França de 18 January 2017 (has links)
As Espécies Reativas de Oxigênio (EROs) conferem proteção aos seres vivos contra os contínuos ataques de microrganismos, além de serem responsáveis por diversos eventos fisiológicos. No entanto um desequilíbrio entre a produção das EROs e os agentes antioxidantes resulta diversos processos patológicos nos mais variados sistemas em seres humanos e em animais. Durante a gestação ocorrem alterações do metabolismo que podem levar a um aumento de subprodutos da oxidação. Assim como a gestação, o nascimento também impõe um período com alta demanda energética, alta tensão de oxigênio e, por consequência, determina um momento crítico na vida do neonato, por ser exigida uma rápida adaptação da condição hipóxica (intra útero) para hiperóxica (extra útero). Desta forma, o objetivo desta dissertação foi verificar o estado oxidativo das éguas no terço final da gestação, no periparto e no pós-parto levando em consideração o efeito da paridade, bem como a condição oxidativa de neonatos durante os primeiros sete dias de vida. Como indicadores de oxidação foram mensurados os níveis de TBARS e oxidação de proteína. Foi quantificado o ferro total e como parâmetros antioxidantes, foram medidas as atividades das enzimas GPx e SOD, e as concentrações de bilirrubina. Nos potros verificamos que a SOD não apresentou diferença significativa no periodo analisado. As concentrações de bilirrubina foram mais baixas no primeiro tempo avaliado, e tanto a bilirrubina total quanto a indireta elevaram-se às 12 horas e então caíram entre as 72h e 168h. Já a GPx demonstrou aumento da sua atividade nos tempos 12 e 72h quando comparada ao tempo 0h. Verificou-se altos níveis de TBARS no primeiro momento pós-nascimento, uma conseguinte diminuição às 12h seguida de estabilização nos demais tempos. Já a avaliação do período gestacional das éguas indicou um efeito de interação entre paridade e tempo gestacional apenas para o ferro total. SOD e oxidação proteica não apresentaram alterações significantes no período estudado. Tanto a GPx quanto as TBARS apresentaram efeito de tempo, com evidente alteração entre o parto, apresentando aumento e o pós-parto apresentando diminuição de atividade e das concentrações dessas variáveis. Concluímos que em potros, a peroxidação lipídica ao nascimento apresentou-se alta sugerindo um balanço pró-oxidativo durante tal período, o que poderia caracterizar um aumento nos níveis de EROs com finalidade de completar importantes eventos fisiológicos. Quanto a bilirrubina indireta e a GPx podemos sugerir que frente aos altos níveis da peroxidação lipídica houve um estímulo para ativação dos sistemas antioxidantes que envolvem essas biomoléculas e que as duas tenham agido concomitantemente visando equilibrar os níveis de EROs. Com relação às éguas, apontamos que a paridade não tem influencia sobre o estabelecimento da homeostase oxidativa em éguas e que no momento do parto as mesmas passam por um desbalanço oxidativo transiente. Ou seja, o desbalanço oxidativo faz parte tanto do momento do parto quanto da primeira semana de vida dos potros, possivelmente desempenhando um papel fisiológico em abas categorias. / Reactive Oxygen Species (ROS) produced protect living beings against the continuous attacks of microorganisms, as well as being responsible for several physiological events, so oxidative homeostasis is a premise. However, an imbalance between the production of ROS and the antioxidant agents causes several pathological processes in the most varied systems in humans and animals. During pregnancy it is suggested that alterations of the metabolism take place, consequently the increase of by-products of the oxidation during the gestational period. Like gestation, the birth also imposes a period with high energy demand, high oxygen tension and, consequently, it determines a critical moment in the life of the newborn because it is required a rapid adaptation of the same to the change of hypoxic condition (intra uterus) To hyperoxic (extra uterus). The aim of this dissertation was to verify the oxidative status of mares in the final third of gestation, peripartum and postpartum, taking into account the parity effect, as well as the oxidative condition of neonates during the first seven days of life. As oxidation indicators, the levels of TBARS and protein oxidation were measured. Total iron was quantified and as antioxidant parameters, activities of GPx and SOD enzymes, and bilirubin concentrations were measured. In the foals we verified that the SOD showed no significant difference in the analyzed time. Bilirubin concentrations were lower in the first time evaluated, and both total and indirect bilirubin increased at 12 hours and then fell between 72h and 168h. On the other hand, GPx showed an increase in its activity in times 12 and 72h when compared to time 0h. There were high levels of TBARS at the first post-birth moment, a consequent decrease at 12h, followed by stabilization at the other times. The results with mares indicated interaction effect between parity and gestational time only for total iron. SOD and protein oxidation did not present significant alterations in the studied period. Both GPx and TBARS presented a time effect, with an evident alteration between childbirth and postpartum, and there was an increase and decrease, respectively, in the activity and concentrations of these variables. We conclude that in foals, lipid peroxidation at birth was high suggesting a pro-oxidative balance during such period, which could characterize an increase in the levels of ROS in order to complete important physiological events. Regarding indirect bilirubin and GPx, we can suggest that in the face of the high levels of lipid peroxidation there was a stimulus for the activation of the antioxidant systems that involve these biomolecules and that the two have acted concomitantly in order to maintain the high levels of EROs at non detrimental levels. Regarding mares, we pointed out that parity has no influence on the establishment of oxidative homeostasis in mares and that at the time of delivery they undergo transient oxidative imbalance. That is, oxidative imbalance is part of both the calving moment and the first week of life of foals, possibly playing a physiological role in categories.
58

Dinâmica folicular e luteal em éguas de diferentes portes

David, Fabíola Freire Albrecht de January 2018 (has links)
Comparações da dinâmica ovariana entre mais de duas raças equinas, sob condições padronizadas, não são encontradas na literatura. Objetivando comparar a dinâmica folicular e luteal, foram realizados exames diários de ultrassonografia durante um intervalo interovulatório contemporâneo, em éguas de pequeno porte (grupo Mini Pony – MP; n=10), médio porte (grupo Large Pony – LP; n=9) e grande porte (grupo Brasileiro de Hipismo – BH; n=12). Concluiu-se que os três grupos diferiram quanto ao máximo diâmetro do folículo pré-ovulatório (FPO) (mm) (MP=36,15; LP=40,95; BH=46,66), diâmetro do FPO um dia antes da ovulação (mm) (MP=35,8; LP=40,55; BH=46,48) e crescimento diário médio do FPO (mm/dia) (MP=2,6; LP=3,05; BH=3,51). O grupo MP diferiu dos demais quanto ao número de folículos por onda ovulatória (MP=4,8; LP=10,11; BH=9,75), número de folículos por dia (MP=4,19; LP=10,27; BH=10,63), número de folículos maiores ou iguais a 10mm (MP=2,98; LP=5,88; BH=5,98), diâmetro do FPO à divergência (mm) (MP=22,62; LP=24,81; BH=25,58), diâmetro do segundo maior folículo à divergência (SMF) (mm) (MP=15,56; LP=21,25; BH=21,83), diferença de diâmetro entre FPO e SMF à divergência (mm) (MP=7,25; LP=3,56; BH=3,75) e área do corpo lúteo (CL) (mm2) (MP=436,1; LP=674,4; BH=720,4). Não houve diferença entre os grupos quanto à duração do ciclo (dias) (MP=21,9; LP=20,22; BH=20,58), ocorrência de divergência (MP=80%; LP=88,89%; BH=100%), dias decorridos entre a emergência do FPO e SMF (MP=0,8; LP=0,89; BH=0,92) e diferença de diâmetro entre estes na emergência (mm) (MP=0,4; LP=0,44; BH=0,5) e na divergência (mm) (MP=7,25; LP=3,56; BH=3,75); dias entre emergência e divergência (MP=5,12; LP=5,5; BH=5,5) e divergência e ovulação (MP=7,12; LP=6,62; BH=6,8), número de ondas menores (MP=0,3; LP=0,33; BH=0,42) e duração do CL (dias) (MP=12,4; LP=14,67; BH=13,92). / Comparisons of ovarian dynamics between more than two equine breeds, under standardized conditions, are not found in the literature. The objective of this study was to compare follicular and luteal dynamics during one contemporary intervulatory interval by daily ultrasonography examinations in small size mares (Mini Pony group - MP; n=10), medium size (Large Pony group - LP; n=9) and large size (Brazilian Warmblood group - BH; n=12). It was concluded that all three groups differed regarding maximum diameter of the preovulatory follicle (POF) (mm) (MP=36.15; LP=40.95; BH=46.66), maximum diameter of POF one day before ovulation (mm) (MP=35.8; LP=40.55; BH=46.48) and the mean daily growth of POF (mm / day) (MP=2.6; LP=3.05; BH=3.51). The MP group differed from LP and BH groups regarding number of follicles per ovulatory wave (MP=4.8; LP=10.11; BH=9.75), number of follicles per day (MP=4.19; LP=10, 27; BH=10.63), number of follicles equal or greater than 10mm (MP=2.98; LP=5.88; BH=5.98), diameter of POF at deviation (mm) (MP=22.62; LP=24.81; BH=25.58), diameter of second largest follicle (SLF) at deviation (MP=15.56; LP=21.25; BH=21.83), diameter difference between FPO and SLF at deviation (mm) (MP=7.25; LP=3.56; BH=3.75), corpus luteum (CL) area (mm2) (MP=436.1; LP=674.4; BH=720.4). There was no difference between groups regarding cycle length (MP=21.9; LP=20.22; BH=20.58), occurrence of deviation (MP=80%; LP=88.89%; BH=100%), days between emergence of POF and SLF (MP=0.8, LP = 0.89, BH = 0.92), and diameter difference between POF and SLF at emergence (mm) (MP=0.4; LP=0.44; BH=0.5) and at deviation (mm) (MP=7.25; LP=3.56; BH=3.75); days between emergence and deviation (MP=5.12; LP=5.5; BH=5.5), deviation and ovulation (MP=5.12; LP=6.62; BH=6.8), number of minor waves (MP = 0.3; LP = 0.33; BH = 0.42) and CL lifespan (days) (MP=12.4; LP=14.67; BH=13.92).
59

O mar e a cidade mudanças climáticas e o desenvolvimento urbano em Joinville (SC) /

Braun, Samara, 1991-, Aumond, Juarês José, 1946-, Universidade Regional de Blumenau. Programa de Pós-Graduação em Desenvolvimento Regional. January 2017 (has links) (PDF)
Orientador: Juarês José Aumond. / Dissertação (Mestrado em Desenvolvimento Regional) - Programa de Pós-Graduação em Desenvolvimento Regional, Centro de Ciências Humanas e da Comunicação, Universidade Regional de Blumenau, Blumenau.
60

Células tronco de tecido adiposo de equinos. Estudo do seu potencial para o tratamento da endometrose / Stem cells from equine adipose tissue. Study of their potential for the treatment of endometrosis

Mambelli, Lisley Inata 15 June 2011 (has links)
A aplicação terapêutica de Células Tronco (CT) em equinos é um campo emergente. Nestes animais, as CT são promissoras para o tratamento de lesões nos tendões e rupturas de ligamentos. Apesar das características e do potencial na restauração de tecidos lesionados, bem como dos efeitos parácrinos destas células, não existem dados a respeito do seu uso no tratamento de desordens sistêmicas que podem acometer os equinos, tais como a endometrose. A endometrose é uma doença progressiva e irreversível que leva a degeneração do endométrio e a formação de um tecido fibroso periglandular, sendo de grande relevância na medicina veterinária, por ser uma das maiores causas de infertilidade. Apesar dos constantes avanços na busca de um tratamento, nenhum obteve sucesso. Levando-se em consideração a importância da doença, o objetivo deste projeto foi utilizar CT, previamente isoladas e caracterizadas pelo nosso grupo, no tratamento da endometrose, visando diminuir o processo inflamatório e a formação do tecido fibroso periglandular. Seis éguas com endometrose foram sincronizadas. Em quatro foram infundidas CT previamente marcadas com Vybrant, e nas outras duas (controle) apenas solução fisiológica. Antes da infusão, foram coletadas biópsias uterinas e amostras para citologia. Após 7, 21 e 61 dias da infusão, foram coletadas novas biópsias e amostras citológicas. Por meio da fluorescência direta observamos a presença das CT marcadas enxertadas tanto no corpo quanto nos cornos uterinos das éguas. Através de análises histológicas observamos uma significativa melhora no aspecto morfológico e na organização do tecido uterino, bem como, das glândulas endometriais, após a infusão das CT, tal resultado foi observado progressivamente ao longo dos dias. Notamos também uma diminuição no processo de fibrose do tecido periglandular. As análises de citologia demonstraram a ausência de inflamação uterina antes e após a infusão das CT. Nossos dados sugerem que existem benefícios na utilização de CT de tecido adiposo de equinos no tratamento do tecido uterino acometido pela endometrose, que clinicamente só poderão ser validados após a prenhez desses animais. / In horses, Stem Cell (SC) therapies are a promising tool to the treatment of many injuries, as tendon lesions and ligaments rupture. Besides the characteristics and the potential in tissue restoration, as well as, paracrine effects of SC, there is no information about the use of them for the treatment of systemic disorders which can commit horses, such as endometrosis. Endometrosis is a progressive and irreversible disease which is defined as active or inactive periglandular and stromal endometrial fibrosis, including glandular alterations within fibrotic foci. Modifications induced by this disease alter the surface of endometrium which, in consequence, led to infertility. Conventional treatments do not reduce the fibrotic process or even help to restore fertility. Considering the importance of this disease, the goal of this project is to use SC, previously isolated and characterized by our group, in the treatment of endometrosis, in order to reduce inflammatory process and periglandular fibrous tissue formation, typical of this disease. Six mares with confirmed endometrosis were synchronized for the use as animal model in this work. In four of animals we infused stem cells previously marked with Vybrant, and the other two (control group) were infused with saline solution. Before the infusion, uterine biopsies and also samples for cytology were collected. After 7, 21 and 61 days of cells infusion new biopsies and cytology samples for analysis were collected. We observed, by direct fluorescence, the presence of marked cells grafted in both body and uterine horns of treated animals. Through histological analysis we observed a significant improvement in morphology and organization of uterine tissue, as well as endometrial glands, after infusion of stem cells, this result was observed progressively throughout the days. Furthermore, we noted a decrease in the process of periglandular tissue fibrosis, after infusion of cells. Cytology analysis showed that the animals have no uterine inflammation before or after infusion of SC. Our data suggest that there are benefits of using stem cells from equine adipose tissue in the treatment of uterus tissue affected by endometriosis, which can only be clinically validated after pregnancy of these animals.

Page generated in 0.033 seconds