1,224 research outputs found

    Monitoramento da furação com brocas helicoidais inteiriças de metal duro

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    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico.Neste trabalho é estudado o comportamento de diferentes tipos de sensores baseados em grandezas indiretas usadas para reconhecimento do desgaste e quebra de brocas inteiriças de metal duro. Os sensores utilizados foram: plataforma piezelétrica; sensor de emissão acústica e sensor de potência do motor principal. Esta análise é efetuada mediante o acompanhamento, em produção e laboratório, do desgaste e quebra de uma broca utilizada em uma aplicação específica. Ao final do trabalho conclui-se que, para a broca estudada, os sensores piezelétricos e de potência do motor são adequados. O sensor de emissão acústica foi utilizado para capturar o sinal de vibração na faixa de frequências de 0,5 a 15 kHz, que não apresentou nenhuma alteração com o desgaste da broca. Para a quebra também considerou-se o sensor piezelétrico como o mais adequado, em função da resposta mais rápida a este tipo de perturbação

    Left ventricular mass and cardiothoracic index in patients with chronic renal disease on hemodialysis

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    Introduction:Left ventricular hypertrophy (LVH) is an independent predictor of cardiovascular risk in patients with chronic renal disease (CRD) on hemodialysis (HD). Objective:To show the usefulness of chest radiography in the diagnosis of LVH in CRD patients on HD. Methods:Cross-sectional study including 100 patients (58 men and 42 women), mean age 46.2 ± 14.0 years, with CRD of all causes, for at least six months on HD. Were obtained echocardiogram and chest x-rays of patients, always up to one hour after the end of HD sessions. Results:LVH was detected in 83 patients (83%), of whom 56 (67.4%) had the concentric pattern and 27 (32.6%) with eccentric pattern of LVH. Cardiomegaly - defined by cardiothoracic index (CTI) > 0.5 - was present in 61 patients (61%). The following were the sensitivity, specificity and accuracy, respectively, for the variable ICT: 66.2%, 70.5% and 68.0%. The Pearson correlation between ICT and index of left ventricular mass (LVMI) was 0.552 (p 0,5 - esteve presente em 61 pacientes (61%). Foram os seguintes os valores de sensibilidade, especificidade e acurácia, respectivamente, para a variável ICT: 66,2%, 70,5% e 68,0%. A correlação de Pearson entre ICT e índice de massa do ventrículo esquerdo (IMVE) foi de 0,552 (p < 0,05) e razão de verossimilhança positivo de 2,2. Conclusão:A radiografia de tórax é um exame seguro e útil como ferramenta diagnóstica de HVE em pacientes com DRC em HD.Universidade Federal de São Paulo (UNIFESP)Universidade Estadual de Ciências da Saúde de AlagoasUniversidade de São PauloUniversidade Federal de AlagoasUniversidade Federal de SergipeUNIFESPSciEL

    The Effects of the Social Hierarchy Destabilization on the Foraging Activity of Eusocial Wasp Mischocyttarus cerberus styx Richards, 1940 (Hymenoptera: Vespidae: Polistinae)

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    The genus Mischocyttarus comprises 245 species of neotropical basal eusocial wasps. They form small colonies (rarely more than few tens of individuals); castes are morphologically undifferentiated and determined behaviorally by agonistic interactions. The aim of this study was to verify the effects of the experimental disruption of social hierarchy on foraging activity of Mischocyttarus cerberus styx. We observed six colonies in postemergence phase and recorded data on the foraging activity under two experimental conditions: (1) removal of lower-ranked females and (2) removal of higher ranked females, except the queen. Our results showed that the removal of higher-ranked females had higher effect on the number of foraging trips of M. cerberus styx than the removal of lower-ranked females (the number of foraging trips/hour decreased by 66.4% and 32.7%, resp.). Such results are likely due to the social organization of this species and the presence of a distinct class of females, which in this study were regarded as intermediates. Our data also showed that, irrespective of the hierarchical status of the females, the removal of two or three individuals affected significantly the number of foraging trips in this species

    The Effects of the Social Hierarchy Destabilization on the Foraging Activity of Eusocial Wasp Mischocyttarus cerberus styx

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    The genus Mischocyttarus comprises 245 species of neotropical basal eusocial wasps. They form small colonies (rarely more than few tens of individuals); castes are morphologically undifferentiated and determined behaviorally by agonistic interactions. The aim of this study was to verify the effects of the experimental disruption of social hierarchy on foraging activity of Mischocyttarus cerberus styx. We observed six colonies in postemergence phase and recorded data on the foraging activity under two experimental conditions: (1) removal of lower-ranked females and (2) removal of higher ranked females, except the queen. Our results showed that the removal of higher-ranked females had higher effect on the number of foraging trips of M. cerberus styx than the removal of lower-ranked females (the number of foraging trips/hour decreased by 66.4% and 32.7%, resp.). Such results are likely due to the social organization of this species and the presence of a distinct class of females, which in this study were regarded as intermediates. Our data also showed that, irrespective of the hierarchical status of the females, the removal of two or three individuals affected significantly the number of foraging trips in this species

    El electrocardiograma en el diagnóstico de la hipertrofia ventricular de pacientes con enfermedad renal crónica

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    BACKGROUND: Left ventricular hypertrophy (LVH) is an independent predictor of cardiovascular risk, and its characterization and prevalence in chronic renal disease (CRD) should be further studied. OBJECTIVE: To establish the diagnosis of LVH in patients with stage-5 CRD using six different electrocardiographic criteria, and to correlate them with left ventricular mass index (LVMI) as obtained by echocardiography. METHODS: Cross-sectional study including 100 patients (58 men and 42 women, mean age 46.2 ± 14.0 years) with CRD of all causes undergoing hemodialysis (HD) for at least six months. Electrocardiography (ECG) and echocardiography were performed in all patients, always up to one hour after the end of the HD sessions. RESULTS: LVH was detected in 83 patients (83%), of whom 56 (67.4%) had the concentric pattern and 27 (32.6%) the eccentric pattern of LVH. Diagnostic sensitivity, specificity and accuracy of all the electrocardiographic methods studied were higher than 50%. Using Pearson's linear correlation for LVMI, only the Sokolow-Lyon voltage criterion did not show a > 0.50 coefficient. Calculation of the likelihood ratio, in turn, showed that ECG has a discriminatory power for the diagnosis of LVH in the population studied, with emphasis on the Cornell-product and Romhilt-Estes criteria. No correlation was observed between LVMI and QTc and QTc dispersion. CONCLUSION: ECG is a useful, efficient, and highly reproducible method for the diagnosis of LVH in HD patients. In this population, the Cornell-product proved to be the most reliable criterion for the detection of LVH.FUNDAMENTO: La hipertrofia ventricular izquierda (HVI) es un factor predictor independiente de riesgo cardiovascular y su caracterización y prevalencia en la enfermedad renal crónica (ERC) carecen de mejor estudio. OBJETIVO: Establecer el diagnóstico de HVI en pacientes con ERC en estadio 5 por seis diferentes criterios electrocardiográficos, correlacionándolos al índice de masa del ventrículo izquierdo (IMVI) que se obtuvo mediante el ecocardiograma. MÉTODOS: Estudio transversal que incluyó a 100 pacientes (58 varones y 42 mujeres, edad de 46,2 ± 14,0 años) con ERC de todas las etiologías, desde hace al menos 6 meses en hemodiálisis (HD). Se obtuvieron electrocardiograma (ECG) y ecocardiograma de los pacientes, siempre hasta una hora tras el término de las sesiones de HD. RESULTADOS: La HVI se detectó en 83 pacientes (83%), de los que 56 (67,4%) presentaban el estándar concéntrico y 27 (32,6%) el estándar excéntrico de HVI. Todos los métodos electrocardiográficos estudiados tuvieron sensibilidad, especificidad y exactitud diagnósticas superiores al 50%. Mediante la correlación lineal de Pearson con el IMVI, solamente el criterio de Sokolow-Lyon voltaje no presentó coeficiente > 0,50. Sin embargo, el cálculo de la razón de verosimilitud evidenció que el ECG tiene poder discriminatorio para diagnóstico de HVI en la población estudiada, con énfasis para los criterios de Producto de Cornell y Romhilt-Estes. No hubo correlación entre IMVI con el QTc y su dispersión. CONCLUSIÓN: El ECG es un método útil, eficaz y de alta reproductibilidad en el diagnóstico de HVI de los pacientes en HD. En esa población, el criterio de Producto de Cornell fue más fiable para la detección de HVI.FUNDAMENTO: A hipertrofia ventricular esquerda (HVE) é um fator preditor independente de risco cardiovascular e sua caracterização e prevalência na doença renal crônica (DRC) carecem de melhor estudo. OBJETIVO: Estabelecer o diagnóstico de HVE em pacientes com DRC em estágio 5 por seis diferentes critérios eletrocardiográficos, correlacionando-os com o índice de massa do ventrículo esquerdo (IMVE) obtido pelo ecocardiograma. MÉTODOS: Estudo transversal que incluiu 100 pacientes (58 homens e 42 mulheres, idade de 46,2 ± 14,0 anos) com DRC de todas as etiologias, há pelo menos seis meses em hemodiálise (HD). Foram obtidos eletrocardiograma (ECG) e ecocardiograma dos pacientes, sempre até uma hora após o término das sessões de HD. RESULTADOS: A HVE foi detectada em 83 pacientes (83%), dos quais 56 (67,4%) apresentavam o padrão concêntrico e 27 (32,6%) o padrão excêntrico de HVE. Todos os métodos eletrocardiográficos estudados tiveram sensibilidade, especificidade e acurácia diagnósticas acima de 50%. Pela correlação linear de Pearson com o IMVE, apenas o critério de Sokolow-Lyon voltagem não apresentou coeficiente > 0,50. Já o cálculo da razão de verossimilhança mostrou que o ECG possui poder discriminatório para diagnóstico de HVE na população estudada, com ênfase para os critérios de Cornell produto e Romhilt-Estes. Não houve correlação entre IMVE com o QTc e sua dispersão. CONCLUSÃO: O ECG é um método útil, eficaz e de alta reprodutibilidade no diagnóstico de HVE dos pacientes em HD. Nessa população, o critério de Cornell produto mostrou-se o mais fidedigno para a detecção de HVE.Universidade Estadual de Ciências da Saúde de AlagoasUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaUNIFESP, EPMSciEL

    Detection of Plasmodium sp. in capybara

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    In the present study, we have microscopically and molecularly surveyed blood samples from 11 captive capybaras (Hydrochaeris hydrochaeris) from the Sanctuary Zoo for Plasmodium sp. infection. One animal presented positive on blood smear by light microscopy. Polymerase chain reaction was carried out accordingly using a nested genus specific protocol, which uses oligonucleotides from conserved sequences flanking a variable sequence region in the small subunit ribosomal RNA (ssrRNA) of all Plasmodium organisms. This revealed three positive animals. Products from two samples were purified and sequenced. The results showed less than 1% divergence between the two capybara sequences. When compared with GenBank sequences, a 55% similarity was obtained to Toxoplasma gondii and a higher similarity (73– 77.2%) was found to ssrRNAs from Plasmodium species that infect reptile, avian, rodents, and human beings. The most similar Plasmodium sequence was from Plasmodium mexicanum that infects lizards of North America, where around 78% identity was found. This work is the first report of Plasmodium in capybaras, and due to the low similarity with other Plasmodium species, we suggest it is a new species, which, in the future could be denominated ''Plasmodium hydrochaeri''

    Efficient synthesis of benzothiazine and acrylamide compounds

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    This article describes the synthesis of the new (2Z)-2-(4-methoxybenzylidene)-6-nitro-4H -benzo[1,4]thiazin-3-one, (2Z)-2-(4-methoxybenzylidene)-4-methyl-6-nitro-4H-benzo[1,4]thiazin-3-one, (2Z)-6-amino-2-(4-methoxybenzylidene)-4H -benzo[1,4]thiazin-3-one, (2Z)-6-butylamino-2-(4-methoxybenzylidene)-4-methyl-4H-benzo[1,4]-thiazin-3-one and (2E)-N-alkyl-N-(2-hydroxy-5-nitrophenyl)-3-phenylacrylamides and the spectroscopic data. The arylidenebenzothiazine compounds were prepared using the Knoevenagel condensation with substituted benzaldehydes in the presence of sodium methoxide in DMF. The presence of a nitro substituent in the 4-position, water and a slightly acid reaction medium in this condensation caused the rupture of the benzothiazine ring and subsequent formation of the phenylacrylamide compounds. A crystallographic data was presented for (2E)-3-(4-bromophenyl)-N-dodecyl-N -(2-hydroxy-5-nitrophenyl) acrylamide.CNPqCoordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES
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