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.

Effects of respiratory muscle work on respiratory and locomotor blood flow during exercise.

Abstract: New Findings What is the central question of this study? Does manipulation of the work of breathing during high-intensity exercise alter respiratory and locomotor muscle blood flow? What is the main finding and its importance? We found that when the work of breathing was reduced during exercise, respiratory muscle blood flow decreased, while locomotor muscle blood flow increased. Conversely, when the work of breathing was increased, respiratory muscle blood flow increased, while locomotor muscle blood flow decreased. Our findings support the theory of a competitive relationship between locomotor and respiratory muscles during intense exercise. Manipulation of the work of breathing (WOB) during near-maximal exercise influences leg blood flow, but the effects on respiratory muscle blood flow are equivocal. We sought to assess leg and respiratory muscle blood flow simultaneously during intense exercise while manipulating WOB. Our hypotheses were as follows: (i) increasing the WOB would increase respiratory muscle blood flow and decrease leg blood flow; and (ii) decreasing the WOB would decrease respiratory muscle blood flow and increase leg blood flow. Eight healthy subjects (n = 5 men, n = 3 women) performed a maximal cycle test (day 1) and a series of constant-load exercise trials at 90% of peak work rate (day 2). On day 2, WOB was assessed with oesophageal balloon catheters and was increased (via resistors), decreased (via proportional assist ventilation) or unchanged (control) during the trials. Blood flow was assessed using near-infrared spectroscopy optodes placed over quadriceps and the sternocleidomastoid muscles, coupled with a venous Indocyanine Green dye injection. Changes in WOB were significantly and positively related to changes in respiratory muscle blood flow (r = 0.73), whereby increasing the WOB increased blood flow. Conversely, changes in WOB were significantly and inversely related to changes in locomotor blood flow (r = 0.57), whereby decreasing the WOB increased locomotor blood flow. Oxygen uptake was not different during the control and resistor trials (3.8 ± 0.9 versus 3.7 ± 0.8 l min−1, P > 0.05), but was lower on the proportional assist ventilator trial (3.4 ± 0.7 l min−1, P < 0.05) compared with control. Our findings support the concept that respiratory muscle work significantly influences the distribution of blood flow to both respiratory and locomotor muscles.

“Ideologia de gênero”: notas para a genealogia de um pânico moral contemporâneo

Abstract: Nos ultimos anos, em diversos contextos nacionais, emergiram debates sobre o que grupos – religiosos e laicos - denominam de “ideologia de genero”. Este artigo busca retracar a genealogia desse termo para compreender a gramatica politica em que se insere. Com este objetivo, retoma textos que o definem ha cerca de vinte anos atras, mapeia onde ele emerge na America Latina e quando passa a ser acionado contra avancos nos direitos sexuais e reprodutivos. Demandas de direitos humanos tem sido interpretadas por empreendedores morais como ameacas ao status quo engendrando, ao mesmo tempo, um pânico moral e um campo discursivo de acao.

Blood glucose threshold and the metabolic responses to incremental exercise tests with and without prior lactic acidosis induction.

Abstract: This study compared the metabolic-ventilatory responses and the glycemic threshold identified during lactate minimum (LM) and individual anaerobic threshold (IAT) tests. In addition, the ability to determine the anaerobic power, aerobic-anaerobic transition (Trans) (e.g. ventilatory threshold; VT) and the maximal oxygen consumption (VO(2max)) all within a single incremental treadmill test (IT) was investigated. Fifteen physically fit men [25.9 (5.5) years; 77.4 (6.5) kg] performed the following: test 1, IT for IAT; and test 2, LM: 30-s Wingate test followed by 8 min rest and then an IT that was the same as test 1. Blood lactate concentration [lac], glucose concentration [gluc], pH, PO(2), PCO(2), base excess (BE) and ventilatory variables were measured. At the beginning of the IT for LM, the ventilation, PO(2) and VO(2) were higher and the pH, BE and PCO(2) were lower in relation to IAT ( P<0.05), while no differences were observed after reaching LM intensity during IT. Moreover, the Trans could be identified by [lac] (IAT, LM), minute ventilation [V(E;) VT identified during IAT protocol (VT-IAT) and VT identified during LM protocol (VT-LM)], and [gluc] (IGT, GM) during the IT for IAT and LM. The velocities (kilometers per hour) corresponding to IAT (12.6+/-1.6), VT-IAT (12.5+/-1.7), IGT (12.6+/-1.6), LM (12.5+/-1.5), VT-LM (12.3+/-1.5), and GM (12.6+/-1.9) were not different from each other and the LM and IAT protocols resulted in the similar VO(2max). We concluded that: (1) after reaching the LM the metabolic responses during IT are similar to IAT; (2) performing a Wingate test prior to an IT does not interfere with the Trans and VO(2max) attainment; (3) and the IGT and GM can predict the Trans.

Sintering of ultrafine undoped SnO2 powder

Abstract: The sintering process of nanometric undoped SnO 2 powder was studied. No macroscopic shrinkage was observed during the sintening process. Grain growth kinetics investigation showed that surface diffusion is the dominant mechanism in the temperature range 500–1300°C. For temperatures higher than 1300°C, high weight loss was measured, suggesting evaporation–condensation as the dominant mass-transport mechanism. Thermogravimetric analysis (TG) and mass spectroscopy studies showed that the surface contamination of the SnO 2 particles by chemical species like H 2 O, OH − and CO 2 , has a strong influence on the role of mass transport controlled by surface diffusion.