Joaquim Sampaio Matias

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BACKGROUND B-type natriuretic peptide is secreted mainly in the left ventricle in response to elevated wall tension. Plasma levels of the peptide correlate positively with cardiac filling pressures, making it an excellent marker for the presence of left ventricular dysfunction. In hypertrophic cardiomyopathy, enhanced production of B-type natriuretic(More)
BACKGROUND and purpose N-terminal probrain natriuretic peptide, which is mainly produced by the heart, is increased in acute stroke. We aimed to determine if N-terminal probrain natriuretic peptide could be a biomarker for ischemic stroke with a cardioembolic cause. METHODS Consecutive sample of acute stroke patients admitted to a Stroke Unit. Ischemic(More)
INTRODUCTION Levosimendan is an inodilatory drug with hemodynamic effects in patients with decompensated chronic heart failure. AIM Short-term (one month) evaluation of clinical, hemodynamic and neurohormonal changes in patients with decompensated chronic heart failure undergoing levosimendan therapy. METHODS Twenty-six (21 male) consecutive patients(More)
We discuss the large set of observables available from the angular distributions of the decayBd → K∗0l+l−. We present a NLO analysis of all observables based on the QCD factorization approach in the low-dilepton mass region and an estimate of Λ/mb corrections. Moreover, we discuss their sensitivity to new physics. We explore the experimental sensitivities(More)
We explore the implications for neutrino masses and mixings within the minimal version of the supersymmetric large-extra-dimensions scenario (MSLED). This model was proposed in hep-ph/0404135 to extract the phenomenological implications of the promising recent attempt (in hep-th/0304256) to address the cosmological constant problem. Remarkably, we find that(More)
We justify the feasibility of substituting a photon leg by a neutrino current in the Euler–Heisenberg Lagrangian to obtain an effective Lagrangian for the process γν → γγν and its crossed reactions. We establish the link between these processes and the four-photon scattering in both the Standard Model and the effective theory. As an application, we compute(More)
We investigate allowed regions in observable space of B → πK, Bd → ππ and Bs → KK decays, characterizing these modes in the Standard Model. After a discussion of a new kind of contour plots for the B → πK system, we focus on the mixing-induced and direct CP asymmetries of the decays Bd → ππ and Bs → KK. Using experimental information on the CP-averaged Bd →(More)
We provide a set of sum rules relating CP-averaged branching ratios and CP-asymmetries of the B → πK modes. They prove to be useful as a mechanism to ‘test’ experimental data given our expectations of the size of isospin breaking. A set of observables emerges providing a simpler interpretation of data in terms of isospin breaking. Moreover, the derivation(More)