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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.
81

Um filtro adaptativo de alto desempenho instaciado do algoritmo GAADT para o processamento de sinais de eletrocardiograma

MACIEL, Andrilene Ferreira 09 September 2015 (has links)
Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2016-11-08T18:59:31Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TESE_IMPRESSÃO_ANDRILENE_VFINAL_bib.pdf: 10222135 bytes, checksum: e23334e08daf26aa1743055d338fbea5 (MD5) / Made available in DSpace on 2016-11-08T18:59:31Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TESE_IMPRESSÃO_ANDRILENE_VFINAL_bib.pdf: 10222135 bytes, checksum: e23334e08daf26aa1743055d338fbea5 (MD5) Previous issue date: 2015-09-09 / A implementação dos algoritmos genéticos (AGs) inspirados no modelo de Holland em hardware para filtrar sinais visa acelerar o tempo de convergência desses algoritmos através da implementação dos módulos considerados um gargalo para uma implementação em software. Porém estes módulos apresentam os mesmos problemas com a representação do cromossomo, a dependência dos operadores genéticos e a representação adotada para o cromossomo e a população, e a perda de cromossomos com características relevantes para a solução do problema ao qual o AG está sendo aplicado. Esta tese apresenta um filtro adaptativo que adota o algoritmo genético baseado em tipos de dados abstratos (GAADT), para o processamento de sinais de ECG, denominado de CGAADT, na plataforma GPU/CUDA. O CGAADT desenvolvido apresenta uma solução de alto desempenho. A escolha por este modelo de algoritmo genético justifica-se pelo fato do GAADT ter sido definido com o intuito de evitar os problemas dos modelos de AG até então encontrados na literatura de computação evolucionária. O GAADT trabalha com uma arquitetura aberta que considera a dinâmica do ambiente o qual os cromossomos estão inseridos, ou seja, a função de adaptação do GAADT busca o cromossomo da população mais adaptado ao ambiente, se este ambiente mudar então a busca realizada pelo GAADT será redirecionado para o cromossomo mais adaptado ao ambiente atual, em tempo de execução, sem a necessidade de interromper a execução atual do GAADT. O resultado obtido pelo GAADT é de melhor qualidade do que os outros modelos de AGs uma vez que este trabalha a definição de gene dominante, que são as informações presentes nos cromossomos relevantes para a solução do problema. Provocando uma explosão exponencial na população do GAADT, na busca por um cromossomo mais adaptado que contenha a maior quantidade possível de genes dominantes, o que pode levar meses de processamento até a coleta de dados em arquiteturas de CPUs convencionais. Um estudo comparativo entre a qualidade dos resultados obtidos ao filtrar os sinais de ECG de pacientes com arritmias sinusal, flutter atrial e fibrilação atrial do CGAADT com outros modelos é apresentado. As experiências avaliadas neste estudo indicam que o CGAADT apresenta uma versão otimizada do GAADT, que permite que todo o processamento do algoritmo genético, seja realizado na GPU, o que resultou em um ganho no tempo total médio do processamento do algoritmo em 17,43% na seleção, 1,39% no cruzamento, 1,12% na mutação, 9,02% na reprodução, 15,11% no processo de inserção de descendentes na população. Tais índices representam um ganho de tempo de processamento de 73,6% relacionado ao algoritmo genético de Holland. / The implementation of genetic algorithms (GAs) inspired by Holland model in hardware to filter signals aims to speed up convergence time of these algorithms by implementing the modules considered a bottleneck for a software implementation. However, these modules have the same problems with the representation of the chromosome, dependence on genetic operators, representation adopted for the chromosome and population, and the loss of chromosomes with relevant features for the solution of the problem to which the AG has being applied. This thesis presents an adaptive filter that takes a genetic algorithm based on abstract data types (GAADT) for processing ECG signals, called CGAADT, the GPU /CUDA plataform. The compact genetic algorithm based on abstract data types (CGAADT) developed presents a solution for high performance of genetic algorithms based on abstract data types. The choice of this genetic algorithm model is justified by the fact that the GAADT have been define with the purpose of avoid the problems of models AG until then found of evolutionary computation literature. The GAADT works with an open architecture that considers the dynamics of the environment to which the chromosomes are inserted, that is, GAADT adaptation function search the most suitable chromosome population to the environment, if this environment change, then the search will be performed by GAADT will be redirected to the chromosome more adapted to the current environment, at runtime, without need to interrupt the current run of GAADT. The result obtained by GAADT has better quality than others AG models, since this works the definition of dominant gene, which are the information provided in the relevant chromosomes to solve the problem. Causing an exponential explosion in GAADT population, in the search for a more suitable chromosome containing the maximum amount of dominant genes, which can take months of processing to data collection in architectures over traditional CPUs. A comparative study of the quality of the results obtained by filtering the ECG signals from patients with sinus arrhythmia, atrial flutter and atrial fibrillation CGAADT with other models is presented. Experiences assessed in this study indicate that CGAADT shows an optimized version of GAADT, which allows all processing of the genetic algorithm is performed on the GPU, which resulted in a gain in the average total processing time of the algorithm in 17,43%selection, 1,39% in crossover, 1,12% in mutation, 9,02% in reproduction, 15,11% in the process of inserting descendants in the population. Such percentage represent a 73,6% enhancement processing gain related to genetic algorithm Holland. Finally, they are made some relevant considerations on the CGAADT and suggested some interesting questions for future work.
82

Efeito dos tratamentos de estimulação e superovulação usando gonadotrofina coriônica equina (eCG) na expressão de genes relacionados à modelagem celular e angiogênese no corpo lúteo bovino / Effect of superovulatory and stimulatory treatments using equine chorionic gonadotropin (eCG) on the expression of genes related to cellular modeling and angiogenesis in the bovine corpus luteum

Gabriela Pacheco Mendes 16 December 2014 (has links)
O uso da gonadotrofina coriônica equina (eCG) tem sido considerado uma potencial ferramenta nos protocolos de estimulação e superovulação para melhorarem o desempenho reprodutivo dos rebanhos. Este fato levou a hipótese de que o tratamento com eCG altera as vias de sinalização intracelular no corpo lúteo (CL) formado. Para testá-la, 18 vacas mestiças de Nelore (Bos indicus) foram divididas em três grupos: controle, estimulado e superovulado. O protocolo de sincronização da ovulação com o uso do dispositivo de P4 foi descrito anteriormente (FÁTIMA et al., 2013). O grupo estimulado recebeu 400 UI de eCG no dia da remoção do dispositivo de P4 e o superovulado recebeu 2000 UI de eCG 4 dias antes. Os animais dos grupos controle e estimulado receberam GnRH no dia 10, enquanto os animais superovulados receberam no dia 8. No sétimo dia após após a administração do GnRH, todos os animais foram abatidos e os CL foram coletados. Foi realizada análise de microarranjo, a partir da qual foram eleitos genes envolvidos na sinalização da esteroidogênese (ADM, MMP9, NOS2), da ativação das metaloproteinases da matriz e do receptor ativado de protease que regula a homeostase e inflamação (PRSS2, PLAU) e da angiogênese (ANG e ANGPT1) e validados por qPCR, western blotting e imuno-histoquímica. A expressão gênica e proteica do PRSS2 e MMP9 foi menor e as células luteínicas grandes e pequenas positivas apresentaram marcação menos intensa nos grupos estimulado e superovulado (P <0,05). A expressão proteica da ANG foi maior no estimulado (P=0,01) e superovulado (P=0,03) e da proteína ANGPT1 foi maior no estimulado (P=0,008). O número de células luteínicas grandes e pequenas positivas para ANG e ANGPT1 foram maiores nos grupos tratados (P <0,05). No estimulado, houve correlação negativa entre os níveis de progesterona e o MMP9 (r = -0,66 e P = 0,03) e com a proteína do PRSS2 (r = -0,63 e P = 0,04). No entanto, houve correlação positiva com a proteína ANG (r = 0,69 e P = 0,03). No superovulado, houve correlação positiva entre a ANG e ANGPT1 (r = 0,96 e P = 0,001). Não houve diferença na expressão de ADM, NOS2 e PLAU nos grupos tratados em relação ao controle. Em resumo, os resultados obtidos são indicativos de que a eCG altera a expressão relativa de genes e proteínas envolvidas nas vias de sinalização de inflamação e a modelação da membrana celular com uma diminuição na expressão do MMP9 e da PRSS2 e na via da angiogênese com maior expressão de ANG em ambos os tratamentos e ANGPT1 em vacas estimuladas. / The use of equine chorionic gonadotropin (eCG) have been considered a potential tool in stimulation and superovulation protocols to improve the reproductive performance of the herd. This fact led to the hypothesis that eCG treatment alters the intracellular signaling pathways in the formed CL. To test that, 18 crossbred Nellore (Bos indicus) cows were divided into three groups: control, stimulated and superovulated. The synchronization protocol with the use of P4 device was previously described (FÁTIMA et al., 2013). The stimulated group received 400 IU eCG at the P4 device removal and superovulated received 2000 IU eCG 4 days before it. Both control and stimulated animals received GnRH on day 10, while superovulated ones received it on day 8. On the seventh day after GnRH administration, CL were collected by slaughter. Microarray analysis was preformed, from which were selected genes involved in the signaling of steroidogenesis (ADM, MMP9, NOS2), activation of matrix metalloproteinases and protease activated receptor that regulates homeostasis and inflammation (PRSS2, PLAU), and angiogenesis (ANG and ANGPT1). They were evaluated by qPCR, western blot and immunohistochemistry. The gene and protein expression of MMP9 and PRSS2 decreased and large and small luteal cells showed weaker staining in stimulated and superovulated groups related to the control group (P <0.05). ANG protein expression was higher on superovulated (P=0.01) and stimulated (P=0.03) and ANGPT1 protein was higher only in stimulated (P=0.008). The number of positive large and small luteal cells for ANG and ANGPT1 were higher in treated groups (P<0.05). In stimulated, there were a negative correlation between progesterone levels and MMP9 (r = 0.03 and P = -0.66) and the PRSS2 protein expression (r = 0.04 and P = -0.63). However, there were a positive correlation with ANG protein expression (r = 0.69 and P = 0.03). In superovulated, there were a positive correlation between ANG and ANGPT1 (r = 0.96 and P = 0.001) and PRSS2 protein expression was negatively correlated with the ANG protein (r = 0.04 and P = -0.96). There was no difference in ADM, NOS2 and PLAU expression in treated groups compared to control. In summary, these findings indicate that eCG alters the relative expression of genes and proteins involved in inflammation and cell modeling signaling pathways by decreasing MMP9 and PRSS2 expression, and on angiogenesis pathway, increasing ANG expression in both stimulated and superovulated animals and ANGPT1 in stimulated cows.
83

Resposta imunológica contra gonadotrofina coriônica equina (eCG) em novilhas Bos taurus e Bos indicus / Immunological response to equine chorionic gonadotropin (eCG) in Bos taurus and Bos indicus heifers

Ana Paula Mantovani 28 October 2010 (has links)
O presente trabalho foi realizado em duas etapas experimentais. O objetivo do Experimento 1 foi avaliar o perfil de produção de anticorpos anti-eCG em novilhas Bos taurus e Bos indicus tratadas uma, duas ou três vezes, com 400 e com 2000UI de eCG. O experimento foi realizado em duas réplicas com o mesmo desenho experimental, porém com padrões raciais distintos. Os animais foram divididos em 6 grupos: os grupos eCG2000UI_1x (n = 5), eCG2000UI_2x (n = 5) e eCG2000UI_3x (n = 5) receberam, respectivamente, um, dois e três tratamentos com 2000 UI de eCG, enquanto os grupos eCG400UI_1x (n = 5), eCG400UI_2x (n = 5) e eCG400UI_3x (n = 5) receberam os mesmos tratamentos porém com 400 UI de eCG. Foram realizadas coletas de sangue semanais por um período de 63 dias, em seguida o intervalo entre as coletas foi de 30 e 60 dias totalizando um período de 300 dias. A dosagem dos anticorpos anti-eCG foi realizada por teste ELISA. O número de tratamentos não influenciou a produção de anticorpos anti-eCG; a produção de anticorpos foi maior em fêmeas Bos taurus que em Bos indicus, e a aplicação de 2000 UI de eCG resultou em maiores concentrações de anticorpos que a aplicação de 400 UI nos primeiros 21 dias após o tratamento e na resposta tardia. O objetivo do Experimento 2 foi avaliar a memória imunológica celular e humoral de fêmeas Bos taurus previamente tratadas com 400 e 2000 UI de eCG, e verificar a influência dessa possível memória imunológica na atividade biológica da molécula de eCG. Além dos animais utilizados no experimento anterior, no Experimento 2 foram incluídos outros nove animais sem tratamento prévio com eCG: eCG2000UI_Controle (n = 5) e eCG400UI_Controle (n = 4). No D0 os animais receberam 2 mg de benzoato de estradiol e um dispositivo intravaginal de progesterona (DIB). Quatro dias mais tarde, as fêmeas dos grupos eCG2000UI_1x, eCG2000UI_2x, eCG2000UI_3x e eCG2000UI_Controle receberam 2000 UI de eCG, enquanto as fêmeas dos grupos eCG400UI_1x, eCG400UI_2x, eCG400UI_3x e eCG400UI_Controle receberam 400 UI de eCG. No momento da retirada do DIB (D8) os animais receberam PGF2 e 1 mg de cipionato de estradiol. Foram realizadas coletas de sangue semanais por 32 dias para dosagem de anticorpos, e duas coletas para avaliação da atividade celular proliferativa no D0 e D32. No momento da retirada do DIB as novilhas foram submetidas a exame ultrassonográfico para avaliação da resposta superestimulatória (no. de folículos > 6 mm) e para mensuração do diâmetro do maior folículo nas fêmeas tratadas com 2000 e 400 UI de eCG, respectivamente. O tratamento prévio não gerou memória imunológica humoral, independente da dose e do número de tratamentos realizados. No entanto, foi observada memória imunológica celular, sendo que esta memória foi maior nos animais submetidos a maior número de tratamentos prévios. Foi observada tendência de efeito de réplica na resposta superestimulatória, e correlação negativa entre a concentração de anticorpos e o número de folículos > 6 mm. O tratamento com 400 UI de eCG não mostrou os mesmos efeitos no diâmetro folicular. / The present study was carried out in two experimental steps. Experiment 1 was designed to evaluate the anti-eCG antibodies production in Bos taurus and Bos indicus heifers, in response to 400 and 2000UI of eCG, employed once, twice or three times. This experiment was performed in two identical experimental designs, however, using distinct genetic groups. Animals where randomly divided in six groups: eCG2000UI_1x (n = 5), eCG2000UI_2x (n = 5) and eCG2000UI_3x (n = 5) were respectively treated with one, two and three injections of 2000 UI of eCG. Groups eCG400UI_1x (n = 5), eCG400UI_2x (n = 5) and eCG400UI_3x (n = 5) were submitted to the same treatment protocol aforementioned; however, eCG dose was 400UI. Animals where then submitted to weekly blood sampling during a 63 days period, and then samples were collected within intervals ranging from 30-60 days, totalizing a period of 300 days. Anti-eCG dosage assay was performed by ELISA. Antibody production was not affected by the number of doses; however, was higher in Bos taurus females. Moreover, higher antibodies levels in the first 21 days after treatment and in the late response were observed when 2000 UI of eCG was applied. The Experiment 2 was focused on the evaluation of cellular and humoral immunological memory of Bos Taurus females previously treated with 400 and 2000 UI of eCG, as well as to figure out influence of the possible immunological response on biological activity of eCG molecule. Besides the animals that were used in the first experiment, nine additional heifers were included in the second trial, which were eCG2000UI_Control (n = 5) and eCG400UI_Control (n = 4). The treatment protocol was: on Day 0 (D0) all heifers received 2 mg of estradiol benzoate and one intravaginal progesterone device (DIB). Four days later, groups eCG2000UI_1x, eCG2000UI_2x, eCG2000UI_3x and eCG2000UI_Control received an injection of 2000 UI eCG, while groups eCG400UI_1x, eCG400UI_2x, eCG400UI_3x and eCG400UI_Control received 400 UI. By the time of DIB withdrawal (D8), animals were treated with PGF2 plus 1 mg of estradiol cipionate treatment. Afterwards, weekly blood samples were collected during 32 days for antibodies assay. Two additional blood samples were performed on day D0 and D32 to evaluate the cellular proliferative activity in response to eCG. In order to evaluate the ovarian stimulatory response (number of follicles > 6mm) in heifers treated with 2000 UI of eCG as well as the size of the largest follicle in those heifers treated with 400UI, ultrasound examination was carried by the time of DIB withdrawal. Humoral immunological memory response was not observed in animals previously treated with 400 or 2000 UI of eCG, regardless the number of treatments. Otherwise, cellular immunological memory response was observed and was higher in animals subjected to an increased number of treatments. A tendency of replicate effect in follicle numbers (> 6mm) was observed, as well as a high negative correlation between antibodies concentration and the number of follicles > 6mm. Same results were not observed when 400 UI of eCG treatment was performed.
84

eCG e densidade vascular em úteros bovinos / eCG and vascular density of bovine uterus

Joana Mona e Pinto 18 December 2009 (has links)
A dinâmica folicular, bem como a preparação do endométrio para a gestação, é dependente do estabelecimento de vascularização adequada. Alguns estudos apontam para a importância do tratamento com eCG após o emprego de protocolos de IATF, de forma a aumentar as taxas de ovulação e prenhez, e para a uma possível propriedade angiogênica, influenciando o fluxo sanguíneo e a vascularização. O objetivo do presente trabalho foi avaliar a influência do eCG na espessura e área do endométrio e miométrio, calibre e área da artéria uterina do corno ipsilateral e também na densidade vascular do endométrio e miométrio de vacas submetidas a tratamentos de sincronização (grupo controle), estimulação do folículo dominante e superovulação. Para tal, foram utilizadas 16 vacas mestiças de Nelore ciclando com escore corporal entre 2 e 3 que foram divididas em 3 grupos de acordo com tratamento hormonal: o grupo controle foi submetido apenas ao protocolo de sincronização da ovulação (n=5), o grupo estimulado recebeu 400 UI de eCG no dia 4 após início do protocolo (n=6) e o grupo superovulado recebeu 2000UI de eCG no dia 8 após início do tratamento (n=5). No dia 5 após a ovulação (p.o) foram realizados exames ultrasonográficos para mensuração do miométrio e endométrio dos cornos uterinos, bem como para análise do calibre da artéria uterina. Os animais foram abatidos, os úteros coletados no dia 6 p.o. e imediatamente fixados em paraformaldeido a 4%. Para análise da densidade vascular, foi realizada imunohistoquímica para o KDR com o intuito de marcação das células endoteliais e contagem dos vasos por estereologia. As espessuras e áreas, tanto do miométrio quanto do endométrio, não foram influenciadas pelos tratamentos. A artéria uterina nos animais superovulados apresentou maior calibre do que nos animais do grupo controle (p< 0,05). A densidade vascular do endométrio nos animais estimulados foi menor quando comparada à dos animais do grupo controle (p<0,05), e no grupo superovulado, a densidade vascular apresentou-se diminuída (p<0,05) no miométrio. Os resultados obtidos sugerem que o aumento de vascularização do endométrio após tratamentos com ECG, relatado em outros trabalhos, seja provavelmente influenciado pelo concepto e não exclusivamente pelo tratamento. Além disso, a influência do eCG no útero pode ser dependente tanto da dose quanto do estágio do ciclo estral. / Follicle dynamic, as well as the uterus preparation for gestation, is dependent of an adequate vascularization establishment. Currently, many studies point towards the importance of eCG treatment following fixed-time artificial insemination (FTAI), in a manner to improve ovulation and gestational rates. Moreover, eCG have been implicated in angiogenesis, leading to important changes in uterine blood flow and vascularization. Thus, the present study was designed to investigate the influence of eCG on the endometrial and myometrial thickness and area; on the caliber and area of the uterine artery of the ipsilateral horn; and, on endometrial and myometrial uterine vascular density of cows submitted to sincronization (control group), stimulation (stimulated group), and superovulatory (superovulated group) treatments. For that, we used 16 cows with body score between 2 and 3, randomly distributed into the 3 above described groups: the cows of the control group (n = 5) did not receive eCG, while the cows of the stimulated group (n = 6) and superovulated group 3 (n = 5) received, respectively, 400 UI and 2000 UI of eCG at days 4 and 8 after the protocol beginning. For endometrial and myometrial measurements, as well as for uterine artery caliber and area analysis, ultrasonographic evaluations were done at day 5 after ovulation. At day 6, the animals were slaughtered, the uterus were harvested and fixed in 4% paraformaldehyde. In order to analyze the vascular density, immunohistochemistry for KDR detection and blood vessels counting by stereology were performed. In all studied groups, treatments did not influence either uterine wall thickness or area. In the superovulated animals, the uterine artery presented higher caliber than in the control ones (P<0.05). Endometrial vascular density of stimulated animals in the ipsilateral uterine horn was lower when compared to that of the control (P<0.05),and in the superovulated, vascular density was lower in the myometrium (P<0.05). These results suggest that the endometrial vascularization increase following eCG treatment, described by other groups, is probably influenced by the concept, not only by the treatment. Moreover, the influence of eCG in the uterus could be dependent of both the hormonal dosis and the estrous cycle phase.
85

Caracterização ultra-estrutural das células luteínicas bovinas derivadas de tratamento com eCG / Ultraestructural characterization of bovine luteal cells derived from ECG treatment

Nathia Nathaly Rigoglio 25 August 2011 (has links)
Biotécnicas aplicadas à reprodução animal são empregadas com o intuito de melhorar qualitativa e quantitativamente os rebanhos. A superovulação assim como a estimulação do folículo dominante utilizando-se doses suprafisiológicas de eCG (gonadotrofina coriônica eqüina) são empregadas em bovinos e bubalinos, mas nem sempre alcançam os resultados esperados. Entretanto, foram relatadas alterações morfofuncionais em corpos lúteos (CL) de animais submetidos a estes tratamentos, o que implica, necessariamente, em levantamento de hipóteses relativas ao(s) mecanismo(s) pelo(s) qual(is) as gonadotrofinas exógenas alteram as funções celulares nos folículos e corpos lúteos resultantes. Com o intuito de melhor compreensão do papel exercido pelo eCG sobre a célula luteínica bovina, 16 vacas foram sincronizadas e submetidas (grupos tratados) ou não (grupo controle) ao tratamento com eCG. O tratamento foi realizado previamente (superovulação) ou posteriormente (estimulação do folículo dominante) ao desvio folicular. No dia 6 após a ovulação, estes animais foram abatidos e os CL coletados para realização de análises histológicas e ultra-estruturais, assim como o sangue coletado para dosagem de progesterona. Para comparação dos dados obtidos entre os diferentes grupos utilizou-se o programa GraphPrism e as médias foram consideradas diferentes quando p < 0.05. Em relação à densidade de mitocôndrias e densidade numérica das mitocôndrias elipsóides não houve diferença significativa entre os grupos estudados. Quando se calculou o volume total das mitocôndrias no CL bovino, houve diferença significativa do grupo superovulado em relação aos outros grupos. Já para as mitocôndrias esferóides observou-se diferença significativa do grupo estimulado comparado aos grupos controle e superovulado. À imunofluorescência os animais do grupo superovulado apresentaram visualmente uma marcação mais fluorescente intensa para mitocôndrias quando comparados aos grupos controle e estimulado; e o grupo estimulado apresentou uma marcação mais intensa em relação ao grupo controle. Houve diferença significativa entre os três grupos em relação à quantidade das células luteínicas grandes. Quando se corrigiu o número de células luteínicas grandes pelo volume do CL, os mesmos resultados foram encontrados. Quanto às medidas do maior diâmetro das células luteínicas grandes houve uma diferença significativa quando comparado o grupo estimulado com os demais. Aspectos qualitativos da microvascularização do CL em animais controle e superovulados revelam vascularização mais abundante no grupo tratado. Estes dados apontam para modificações morfológicas da célula luteínica e do CL bovino direcionadas à maior produção hormonal após tratamento com eCG e indicam que doses diferentes aplicadas em momentos diferentes do ciclo estral levam à respostas diversas da célula luteínica e do próprio CL. / Biotechnologies applied to animal reproduction are employed in order to improve livestock quality and quantity. Superovulation and the stimulation of the dominant follicle using supraphysiological doses of eCG (equine chorionic gonadotropin) are used in cattle and buffaloes, but not always achieve the expected results. However, morphofunctional changes in corpora lutea (CL) derived from animals submitted to these treatments were reported, which necessarily implies a survey of hypotheses regarding the mechanism(s) by which exogenous gonadotrophins result in altered cellular functions in the follicles and corpora lutea. In order to better understand the role played by eCG on bovine luteal cells, 16 cows were synchronized and submitted (treated groups) or not (control group) to treatment with eCG. The treatment was performed previously (superovulation) or after (stimulation of the dominant follicle) follicular deviation. At 6 days after ovulation, animals were slaughtered and the CL collected for histological and ultrastructural analysis, as well as blood for determining plasmaprogesterone.For statistical analysis the program Graph Prism was used and mean considered significant different when p < 0.05. In relation to mitochondria number and volume density there were no differences among the studied groups. Values of mitochondria total volume in CL were different if stimulated was compared to the other groups. Imunofluoresce for mitochondria showed a more intensive signal for animals from the superovulated group, followed by animals belonging to the stimulated group. The number of large luteal cells was different among all groups. Even though this number was corrected by CL volume, the same results were found. The biggest diameter of large luteal cells was compared among the groups and stimulated group showed higher values. Qualitative aspects of CL microvascularization in control and superovulated animals reveal more abundant vascularization in treated group. These data point towards morphological modification of bovine CL and luteal cell directed to increased hormonal production after eCG treatment. Moreover, results indicate that different eCG dosis applied in different time points of estrous cycle lead to different responses from CL and luteal cells.
86

Study on a resource-saving cloud based long-term ECG monitoring system using machine learning algorithms

Cheng, Ping 19 April 2018 (has links)
Electrocardiogram (ECG) records the electrical impulses from myocardium, reflects the underlying dynamics of the heart and has been widely exploited to detect and identify cardiac arrhythmias. This dissertation examines a resource-saving cloud based long-term ECG (CLT-ECG) monitoring system which consists of an ECG raw data acquisition system, a mobile device and a serve. Three issues that are critically pertaining to the effectiveness and efficiency of the monitoring system are studied: the detection of life-threatening arrhythmias, the discrimination of normal and abnormal heartbeats to facilitate the resource-saving operation and the multi-class heartbeat classification algorithm for non-life-threatening arrhythmias. The detection algorithm for life-threatening ventricular arrhythmias, which is critical to saving patients’ lives, is investigated by exploiting personalized features. Two new personalized features, namely, aveCC and medianCC, are extracted based on the correlation coefficients between a patient-specific regular QRS-complex template and his/her real-time ECG data, characterizing subtle differences in the QRS complexes among different people. A small set of the most effective features is selected for efficient performance and real-time operation using Support Vector Machines (SVMs). The effectiveness of the proposed algorithm is validated in enhancing the performance under both the record-based and database-based data divisions. The classification algorithm achieves results outperforming the existing classification performances using top-two or top-three features. A novel patient-specific arrhythmia detection algorithm, which discriminates the normal and abnormal heartbeats, is proposed using One-Class SVMs. Conventionally, CLT-ECG systems are used to solve problems such as the portable problem and the difficulty of capturing the intermittent arrhythmias. However, CLT-ECG systems are subject to several practical limitations: battery power restriction, network congestion and heavily redundant ECG data. To overcome these problems, a resource-saving CLT-ECG system is studied, in which a novel arrhythmia detection algorithm closely related to the resource-saving rate is proposed and examined in detail. The proposed arrhythmia detection algorithm explores two types of variations: waveform change indicator (WCI), which reflects a change within one heartbeat; modified RR interval ratio (modRRIR), which characterizes the successive heartbeat interval variation. The overall classification result is obtained from combining the results separately adopting WCI and modRRIR. The proposed algorithm is validated using the public ECG database with a result outperforming others in the literature, as well as using the data collected from the ECG platform HeartCarer built in our research group. Considering the multi-class classification in the cloud server, a patient-specific single-lead ECG heartbeat classification strategy is proposed to discriminate ventricular ectopic beats (VEBs) and Supraventricular Ectopic Beats (SVEBs). Two types of features are extracted: Intra-beat features characterize the distortion of the waveform within one heartbeat, while inter-beat features reflect the variation between successive heartbeats. A novel fusion strategy consisting of a global classifier and a local classifier is presented. The local classifier is obtained using the high-confidence heartbeats extracted from the first 5-minute data of a specific patient, while the global classifier is trained by the public training data. The advantage of the developed strategy is that fully automatic classification is realized without the intervention of physicians. Finally, simulation results show that comparable or even better classification performance is achieved, which validates the effectiveness of the proposed strategy. / Graduate / 2019-03-19
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Analyse et reconnaissance de signaux vibratoires : contribution au traitement et à l'analyse de signaux cardiaques pour la télémédecine / Analysis and recognition of vibratory signals : contribution to the treatment and analysis of cardiac signals for telemedecine

Beya, Ouadi 15 May 2014 (has links)
Le coeur est un muscle. Son fonctionnement mécanique est celui d'une pompe chargée de distribuer et de récupérer le sang dans les poumons et dans le système cardiovasculaire. Son fonctionnement électrique est régulé par le son noeud sinusal, un stimulateur ou régulateur électrique chargé de déclencher les battements naturels du coeur qui rythment le fonctionnement du corps. Les médecins surveillent ce fonctionnement électromécanique du coeur en enregistrant un signal électrique appelé électrocardiogramme (ECG) ou un signal sonore : le phono-cardiogramme (PCG). L'analyse et le traitement de ces deux signaux sont fondamentaux pour établir un diagnostic et aider à déceler des anomalies et des pathologies cardiaques. L’objectif de cette thèse est de développer des techniques de traitement des signaux ECG et notamment PCG afin d’aider le médecin dans son analyse de ces signaux. L’idée de fond est de mettre en point des algorithmes relativement simples et peu coûteux en temps de calcul. Le premier intérêt serait de garantir leur implantation aisée dans un système mobile de surveillance cardiaque à l’usage du médecin, voire du patient. Le deuxième intérêt réside dans la possibilité d’une analyse automatique en temps réel des signaux avec le dispositif mobile, autorisant le choix de la transmission de ces signaux pour une levée de doute. De nombreux travaux ont mené à des avancées significatives dans l’analyse des signaux ECG et la reconnaissance automatiques des pathologies cardiaques. Des bases de données de signaux réels ou synthétiques annotées permettent également d’évaluer les performances de toute nouvelle méthode. Quant aux signaux PCG, ils sont nettement moins étudiés, difficiles à analyser et à interpréter. Même si les grandes familles de méthodes (Fourier, Wigner Ville et ondelettes) ont été testées, elles n’autorisent pas une reconnaissance automatique des signatures, d’en avoir une analyse et une compréhension assez fines.La Transformée en Ondelettes (TO) sur les signaux cardiaques a montré son efficacité pour filtrer et localiser les informations utiles mais elle fait intervenir une fonction externe de traitement (ondelette mère) dont le choix dépend de la connaissance au préalable du signal à traiter. Ce n'est pas toujours adapté aux signaux cardiaques. De plus, la Transformée en ondelettes induit généralement une imprécision dans la localisation due à la fonction externe et éventuellement au sous-échantillonnage des signatures. La nature non stationnaire de l'ECG et du PCG et leur sensibilité aux bruits rendent difficile la séparation d’une transition informative d'une transition due aux bruits de mesure. Le choix de l'outil de traitement doit permettre un débruitage et une analyse de ces signaux sans délocalisation des singularités ni altération de leurs caractéristiques. En réponse à nos objectifs et considérant ces différents problèmes, nous proposons de nous appuyer principalement sur la décomposition modale empirique (EMD) ou transformée de Hilbert Huang (THH) pour développer des solutions. L’EMD est une approche non linéaire capable de décomposer le signal étudié en fonctions modales intrinsèques (IMF), oscillations du type FM-AM, donnant ainsi une représentation temps/échelle du signal. Associée à la transformée de Hilbert (TH), la THH permet de déterminer les amplitudes instantanées (AI) et les fréquences instantanées (FI) de chaque mode, menant ainsi à une représentation temps/fréquence des signaux.Sans faire intervenir une fonction externe, on peut ainsi restaurer (réduction de bruit), analyser et reconstruire le signal sans délocalisation de ses singularités. Cette approche permet de localiser les pics R de l'ECG, déterminer le rythme cardiaque et étudier la variabilité fréquentielle cardiaque (VFC), localiser et analyser les composantes des bruits B1 et B2 du PCG. / The heart is a muscle. Its mechanical operation is like a pump charged for distributing and retrieving the blood in the lungs and cardiovascular system. Its electrical operation is regulated by the sinus node, a pacemaker or electric regulator responsible for triggering the natural heart beats that punctuate the functioning of the body.Doctors monitor the electromechanical functioning of the heart by recording an electrical signal called an electrocardiogram (ECG) or an audible signal : the phonocardiogram (PCG). The analysis and processing of these two signals are essential for diagnosis, to help detect anomalies and cardiac pathologies.The objective of this thesis is to develop signal processing tools on ECG and PCG to assist cardiologist in his analysis of these signals. The basic idea is to develop algorithms of low complexity and having inexpensive computing time. The primary interest is to ensure their easy implementation in a mobile heart monitoring system for use by the doctor or the patient. The second advantage lies in the possibility of automatic real-time analysis of signals with the mobile device, allowing control of the transmission of these signals to a removal of doubt.Numerous studies have led to significant advances in the analysis of ECG signals and the automatic recognition of cardiac conditions. Databases of real or synthetic signals annotated also assess the performance of new methods. PCG signals are much less studied, difficult to analyze and to interpret. The main methods (Fourier, wavelet and Wigner Ville) were tested : they do not allow automatic recognition of signatures, and an accurate understanding of their contents.Wavelet Transform (WT) on cardiac signals showed its effectiveness to filter and locate useful information, but it involves an external processing function (mother wavelet) whose the choice depends on the prior knowledge on the signal to be processed. This is not always suitable for cardiac signals. Moreover, the wavelet transform generally induces inaccuracies in the location due to the external function and optionally due to the sub- sampling of the signatures.The non-stationary nature of the ECG and PCG and their sensitivity to noise makes it difficult to separate an informative transition of a transition due to measurement noise. The choice of treatment tool should allow denoising and analysis of these signals without alteration or the processing tool delocalization of the singularities.In response to our objectives and considering these problems, we propose to rely primarily on empirical mode decomposition (EMD) and Hilbert Huang Transform (HHT) to develop solutions. The EMD is a non linear approach decomposing the signal in intrinsic signal (IMF), oscillations of the type FM-AM, giving a time/scale signal representation. Associated with the Hilbert transform (TH), the THH determines the instantaneous amplitude (IA) and instantaneous frequency (IF) of each mode, leading to a time/frequency representation of the ECG and PCG.Without involving an external function, EMD approach can restore (noise reduction), analyze and reconstruct the signal without relocation of its singularities. This approach allows to locate R peaks of the ECG, heart rate and study the cardiac frequency variability (CFV), locate and analyze the sound components B1 and B2 of the PCG.Among the trials and developments that we made, we present in particular a new method (EDA : empirical denoising approach) inspired by the EMD approach for denoising cardiac signals. We also set out the implementation of two approaches for locating ECG signature (QRS complex, T and P waves). The first is based on the detection of local maxima : in using Modulus Maxima and Lipschitz exponent followed by a classifier. The second uses NFLS, wich an nonlinear approach for the detection and location of unique transitions in the discrete domain.
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Chaotic Modeling Of Electroencephalographic Signals With Application To Compression

Kavitha, V 12 1900 (has links) (PDF)
No description available.
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Modélisations polynomiales des signaux ECG : applications à la compression / Polynomial modelling of ecg signals with applications to data compression

Tchiotsop, Daniel 15 November 2007 (has links)
La compression des signaux ECG trouve encore plus d’importance avec le développement de la télémédecine. En effet, la compression permet de réduire considérablement les coûts de la transmission des informations médicales à travers les canaux de télécommunication. Notre objectif dans ce travail de thèse est d’élaborer des nouvelles méthodes de compression des signaux ECG à base des polynômes orthogonaux. Pour commencer, nous avons étudié les caractéristiques des signaux ECG, ainsi que différentes opérations de traitements souvent appliquées à ce signal. Nous avons aussi décrit de façon exhaustive et comparative, les algorithmes existants de compression des signaux ECG, en insistant sur ceux à base des approximations et interpolations polynomiales. Nous avons abordé par la suite, les fondements théoriques des polynômes orthogonaux, en étudiant successivement leur nature mathématique, les nombreuses et intéressantes propriétés qu’ils disposent et aussi les caractéristiques de quelques uns de ces polynômes. La modélisation polynomiale du signal ECG consiste d’abord à segmenter ce signal en cycles cardiaques après détection des complexes QRS, ensuite, on devra décomposer dans des bases polynomiales, les fenêtres de signaux obtenues après la segmentation. Les coefficients produits par la décomposition sont utilisés pour synthétiser les segments de signaux dans la phase de reconstruction. La compression revient à utiliser un petit nombre de coefficients pour représenter un segment de signal constitué d’un grand nombre d’échantillons. Nos expérimentations ont établi que les polynômes de Laguerre et les polynômes d’Hermite ne conduisaient pas à une bonne reconstruction du signal ECG. Par contre, les polynômes de Legendre et les polynômes de Tchebychev ont donné des résultats intéressants. En conséquence, nous concevons notre premier algorithme de compression de l’ECG en utilisant les polynômes de Jacobi. Lorsqu’on optimise cet algorithme en supprimant les effets de bords, il dévient universel et n’est plus dédié à la compression des seuls signaux ECG. Bien qu’individuellement, ni les polynômes de Laguerre, ni les fonctions d’Hermite ne permettent une bonne modélisation des segments du signal ECG, nous avons imaginé l’association des deux systèmes de fonctions pour représenter un cycle cardiaque. Le segment de l’ECG correspondant à un cycle cardiaque est scindé en deux parties dans ce cas: la ligne isoélectrique qu’on décompose en séries de polynômes de Laguerre et les ondes P-QRS-T modélisées par les fonctions d’Hermite. On obtient un second algorithme de compression des signaux ECG robuste et performant. / Developing new ECG data compression methods has become more important with the implementation of telemedicine. In fact, compression schemes could considerably reduce the cost of medical data transmission through modern telecommunication networks. Our aim in this thesis is to elaborate compression algorithms for ECG data, using orthogonal polynomials. To start, we studied ECG physiological origin, analysed this signal patterns, including characteristic waves and some signal processing procedures generally applied ECG. We also made an exhaustive review of ECG data compression algorithms, putting special emphasis on methods based on polynomial approximations or polynomials interpolations. We next dealt with the theory of orthogonal polynomials. We tackled on the mathematical construction and studied various and interesting properties of orthogonal polynomials. The modelling of ECG signals with orthogonal polynomials includes two stages: Firstly, ECG signal should be divided into blocks after QRS detection. These blocks must match with cardiac cycles. The second stage is the decomposition of blocks into polynomial bases. Decomposition let to coefficients which will be used to synthesize reconstructed signal. Compression is the fact of using a small number of coefficients to represent a block made of large number of signal samples. We realised ECG signals decompositions into some orthogonal polynomials bases: Laguerre polynomials and Hermite polynomials did not bring out good signal reconstruction. Interesting results were recorded with Legendre polynomials and Tchebychev polynomials. Consequently, our first algorithm for ECG data compression was designed using Jacobi polynomials. This algorithm could be optimized by suppression of boundary effects, it then becomes universal and could be used to compress other types of signal such as audio and image signals. Although Laguerre polynomials and Hermite functions could not individually let to good signal reconstruction, we imagined an association of both systems of functions to realize ECG compression. For that matter, every block of ECG signal that matches with a cardiac cycle is split in two parts. The first part consisting of the baseline section of ECG is decomposed in a series of Laguerre polynomials. The second part made of P-QRS-T waves is modelled with Hermite functions. This second algorithm for ECG data compression is robust and very competitive.
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Přenosný monitor EKG / Transportable ECG monitor

Vepřková, Hana January 2015 (has links)
The first two chapters are devoted to theoretical analysis of issues relating to portable EKG monitor. This chapters are aimed to further acquaint the reader with the issue for subsequent easier of understanding on further steps in the implementation of the device which will be contain in the following chapters. The first chapter is mainly a medical nature. We describe the anatomy and functional properties of the heart. In the next chapter we are deal with detail of electrocardiograph and the conditions for its proper function. Other chapters are devoted to the actual implementation of the facility. We are dealing with the issue of build functional portable EKG monitor. This practical part begins by fourth chapter, which consists block diagram of the device and discusses the required parameters. Next most extensive chapter is devoted to a detailed breakdown of the electrical circuit, including the calculation of the individual components. The last chapter describes the implementation and outcome measurements on test persons.

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