Federal University of São Carlos

About: Federal University of São Carlos is a education organization based out in São Carlos, Brazil. It is known for research contribution in the topics: Population & Microstructure. The organization has 16471 authors who have published 34057 publications receiving 456654 citations. The organization is also known as: UFSCar & Federal University of São Carlos.

Blood glucose responses in humans mirror lactate responses for individual anaerobic threshold and for lactate minimum in track tests.

Abstract: The equilibrium point between blood lactate production and removal (La−min) and the individual anaerobic threshold (IAT) protocols have been used to evaluate exercise. During progressive exercise, blood lactate [La−]b, catecholamine and cortisol concentrations, show exponential increases at upper anaerobic threshold intensities. Since these hormones enhance blood glucose concentrations [Glc]b, this study investigated the [Glc] and [La−]b responses during incremental tests and the possibility of considering the individual glucose threshold (IGT) and glucose minimum (Glcmin) in addition to IAT and La−min in evaluating exercise. A group of 15 male endurance runners ran in four tests on the track 3000 m run (v3km); IAT and IGT – 8 × 800 m runs at velocities between 84% and 102% of v3km; La−min and Glcmin– after lactic acidosis induced by a 500-m sprint, the subjects ran 6 × 800 m at intensities between 87% and 97% of v3km; endurance test (ET) – 30 min at the velocity of IAT. Capillary blood (25 μl) was collected for [La−]b and [Glc]b measurements. The IAT and IGT were determined by [La−]b and [Glc]b kinetics during the second test. The La−min and Glcmin were determined considering the lowest [La−] and [Glc]b during the third test. No differences were observed (P 0.05). We concluded that for these subjects it was possible to evaluate the aerobic capacity by IGT and Glcmin as well as by IAT and La−min.

Room-temperature photoluminescence of BaTiO3: Joint experimental and theoretical study

Abstract: Strong photoluminescent emission has been measured at room temperature for noncrystalline $\mathrm{Ba}\mathrm{Ti}{\mathrm{O}}_{3}$ (BT) perovskite powders. A joint experimental and theoretical study has been carried out to rationalize this phenomenon. From the experimental side, BT powder samples have been synthesized following a soft chemical processing, their crystal structure has been confirmed by x-ray data and the corresponding photoluminescence (PL) properties have been measured. Only the structurally disordered samples present PL at room temperature. From the theoretical side, first-principles quantum-mechanical techniques, based on density-functional theory at the B3LYP level, have been employed to study the electronic structure of crystalline (BT-$\mathrm{c}$) and asymmetric (BT-$\mathrm{a}$) models. Theoretical and experimental results are found to be consistent and their confrontation leads to an interpretation of the PL apparition at room temperature in the structurally disordered powders.

Sulfonyl Fluoride Synthesis through Electrochemical Oxidative Coupling of Thiols and Potassium Fluoride.

Abstract: Sulfonyl fluorides are valuable synthetic motifs for a variety of applications, among which sulfur(VI) fluoride exchange-based "click chemistry" is currently the most prominent. Consequently, the development of novel and efficient synthetic methods to access these functional groups is of great interest. Herein, we report a mild and environmentally benign electrochemical approach to prepare sulfonyl fluorides using thiols or disulfides, as widely available starting materials, in combination with KF, as an inexpensive, abundant and safe fluoride source. No additional oxidants nor additional catalysts are required and, due to mild reaction conditions, the reaction displays a broad substrate scope, including a variety of alkyl, benzyl, aryl and heteroaryl thiols or disulfides.