992 resultados para Volume Bragg grating (VBG)
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FUNDAMENTO: O aumento do Volume do Átrio Esquerdo Indexado (VAEi) tem sido associado à Disfunção Diastólica (DD) do Ventrículo Esquerdo (VE), considerado marcador de eventos cardiovasculares (fibrilação atrial, acidente vascular cerebral, insuficiência cardíaca, e óbito). OBJETIVO: Avaliar a relação entre VAEi e diferentes graus de DD em pacientes brasileiros submetidos ao ecocardiograma, estudando os determinantes do aumento do VAEi nesta amostra. MÉTODOS: Selecionamos 500 pacientes ambulatoriais submetidos a ecocardiografia, após exclusão de arritmia, cardiopatia valvar ou congênita, marca-passo permanente ou janela ecocardiográfica inadequada. O VAEi foi obtido pelo método de Simpson; classificou-se a DD segundo diretrizes atuais. Variáveis clínicas e ecocardiográficas foram submetidas a análise multivariada de regressão linear. RESULTADOS: A idade média foi de 52 ± 15 anos, 53% do sexo masculino, 55% hipertensos, 9% coronariopatas, 8% diabéticos, 24% obesos, 47% com hipertrofia VE, fração de ejeção média do VE: 69,6 ± 7,2%. A prevalência de DD na amostra foi de 33,8% (grau I: 66%, grau II: 29% e grau III: 5%). Houve aumento progressivo das dimensões do VAEi conforme o grau de DD: 21 ± 4 mL/m² (ausente), 26 ± 7 mL/m² (grau I), 33 ± 5 mL/m² (grau II), 50 ± 5 mL/m2 (grau III) (p < 0,001). Os preditores independentes de aumento do VAEi nesta amostra foram idade, massa ventricular esquerda, espessura relativa de parede, fração de ejeção do VE e relação E/e'. CONCLUSÃO: A DD contribui para o remodelamento atrial esquerdo. O aumento do VAEi expressa a gravidade da DD e está associado de forma independente com idade, hipertrofia ventricular esquerda, disfunção sistólica e aumento das pressões de enchimento do VE.
kinetic analysis of ester hydrolysis reactions considering volume and enthalpy changes due to mixing
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Magdeburg, Univ., Fak. für Verfahrens- und Systemtechnik, Diss., 2012
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Background: According to some international studies, patients with acute coronary syndrome (ACS) and increased left atrial volume index (LAVI) have worse long-term prognosis. However, national Brazilian studies confirming this prediction are still lacking. Objective: To evaluate LAVI as a predictor of major cardiovascular events (MCE) in patients with ACS during a 365-day follow-up. Methods: Prospective cohort of 171 patients diagnosed with ACS whose LAVI was calculated within 48 hours after hospital admission. According to LAVI, two groups were categorized: normal LAVI (≤ 32 mL/m2) and increased LAVI (> 32 mL/m2). Both groups were compared regarding clinical and echocardiographic characteristics, in- and out-of-hospital outcomes, and occurrence of ECM in up to 365 days. Results: Increased LAVI was observed in 78 patients (45%), and was associated with older age, higher body mass index, hypertension, history of myocardial infarction and previous angioplasty, and lower creatinine clearance and ejection fraction. During hospitalization, acute pulmonary edema was more frequent in patients with increased LAVI (14.1% vs. 4.3%, p = 0.024). After discharge, the occurrence of combined outcome for MCE was higher (p = 0.001) in the group with increased LAVI (26%) as compared to the normal LAVI group (7%) [RR (95% CI) = 3.46 (1.54-7.73) vs. 0.80 (0.69-0.92)]. After Cox regression, increased LAVI increased the probability of MCE (HR = 3.08, 95% CI = 1.28-7.40, p = 0.012). Conclusion: Increased LAVI is an important predictor of MCE in a one-year follow-up.
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Introduction: Although diuretics are mainly used for the treatment of acute decompensated heart failure (ADHF), inadequate responses and complications have led to the use of extracorporeal ultrafiltration (UF) as an alternative strategy for reducing volume overloads in patients with ADHF. Objective: The aim of our study is to perform meta-analysis of the results obtained from studies on extracorporeal venous ultrafiltration and compare them with those of standard diuretic treatment for overload volume reduction in acute decompensated heart failure. Methods: MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials databases were systematically searched using a pre‑specified criterion. Pooled estimates of outcomes after 48 h (weight change, serum creatinine level, and all-cause mortality) were computed using random effect models. Pooled weighted mean differences were calculated for weight loss and change in creatinine level, whereas a pooled risk ratio was used for the analysis of binary all-cause mortality outcome. Results: A total of nine studies, involving 613 patients, met the eligibility criteria. The mean weight loss in patients who underwent UF therapy was 1.78 kg [95% Confidence Interval (CI): −2.65 to −0.91 kg; p < 0.001) more than those who received standard diuretic therapy. The post-intervention creatinine level, however, was not significantly different (mean change = −0.25 mg/dL; 95% CI: −0.56 to 0.06 mg/dL; p = 0.112). The risk of all-cause mortality persisted in patients treated with UF compared with patients treated with standard diuretics (Pooled RR = 1.00; 95% CI: 0.64–1.56; p = 0.993). Conclusion: Compared with standard diuretic therapy, UF treatment for overload volume reduction in individuals suffering from ADHF, resulted in significant reduction of body weight within 48 h. However, no significant decrease of serum creatinine level or reduction of all-cause mortality was observed.
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Background:Left atrial volume (LAV) is a predictor of prognosis in patients with heart failure.Objective:We aimed to evaluate the determinants of LAV in patients with dilated cardiomyopathy (DCM).Methods:Ninety patients with DCM and left ventricular (LV) ejection fraction ≤ 0.50 were included. LAV was measured with real-time three-dimensional echocardiography (eco3D). The variables evaluated were heart rate, systolic blood pressure, LV end-diastolic volume and end-systolic volume and ejection fraction (eco3D), mitral inflow E wave, tissue Doppler e´ wave, E/e´ ratio, intraventricular dyssynchrony, 3D dyssynchrony index and mitral regurgitation vena contracta. Pearson´s coefficient was used to identify the correlation of the LAV with the assessed variables. A multiple linear regression model was developed that included LAV as the dependent variable and the variables correlated with it as the predictive variables.Results:Mean age was 52 ± 11 years-old, LV ejection fraction: 31.5 ± 8.0% (16-50%) and LAV: 39.2±15.7 ml/m2. The variables that correlated with the LAV were LV end-diastolic volume (r = 0.38; p < 0.01), LV end-systolic volume (r = 0.43; p < 0.001), LV ejection fraction (r = -0.36; p < 0.01), E wave (r = 0.50; p < 0.01), E/e´ ratio (r = 0.51; p < 0.01) and mitral regurgitation (r = 0.53; p < 0.01). A multivariate analysis identified the E/e´ ratio (p = 0.02) and mitral regurgitation (p = 0.02) as the only independent variables associated with LAV increase.Conclusion:The LAV is independently determined by LV filling pressures (E/e´ ratio) and mitral regurgitation in DCM.
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Magdeburg, Univ., Fak. für Mathematik, Diss., 2011
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Com a finalidade de se verificar a influência do volume de terra disponível no desenvolvimento vegetativo da berinjela (Solanun melongena L.), conduziu-se um ensaio, em condições de casa de vegetação, no Setor de Horticultura da E.S.A, "Luiz de Queiroz", em Piracicaba, SP, utilizando-se da cultivar híbrida F 100. Foram utilizados recipientes (vasos) de 5 tamanhos diferentes: 200, 450, 3000, 4750 e 9000 cm³ de capacidade. Através dos resultados obtidos pode-se concluir que: quanto maior o recipiente utilizado maior o desenvolvimento vegetativo da beringela, até um ponto em que poderia haver uma menor produtividade por unidade de área plantada. Para a berinjela, há a necessidade de recipiente que corresponda a uma capacidade de, no mínimo, 4750 centímetros cúbicos de substrato.
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Fieldiana Zoology v.14, no. 4
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v.12:no.19(1929)
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v.7:no.13(1912)
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v.1:no.11(1917)
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v.1:no.18(1900)