Right atrial stretch alters fore- and hind-brain expression of c-fos and inhibits the rapid onset of salt appetite

The inflation of an intravascular balloon positioned at the superior vena cava and right atrial junction (SVC-RAJ) reduces sodium or water intake induced by various experimental procedures (e.g. sodium depletion; hypovolaemia). In the present study we investigated if the stretch induced by a balloon at this site inhibits a rapid onset salt appetite, and if this procedure modifies the pattern of immunohistochemical labelling for Fos protein (Fos-ir) in the brain. Male Sprague-Dawley rats with SVC-RAJ balloons received a combined treatment of furosemide (Furo; 10 mg (kg bw)(-1)) plus a low dose of the angiotensin-converting enzyme inhibitor captopril (Cap; 5 mg (kg bw)(-1)). Balloon inflation greatly decreased the intake of 0.3 M NaCl for as long as the balloon was inflated. Balloon inflation over a 3 h period following Furo-Cap treatment decreased Fos-ir in the organum vasculosum of the lamina terminalis and the subfornical organ and increased Fos-ir in the lateral parabrachial nucleus and caudal ventrolateral medulla. The effect of balloon inflation was specific for sodium intake because it did not affect the drinking of diluted sweetened condensed milk. Balloon inflation and deflation also did not acutely change mean arterial pressure. These results suggest that activity in forebrain circumventricular organs and in hindbrain putative body fluid/cardiovascular regulatory regions is affected by loading low pressure mechanoreceptors at the SVC-RAJ, a manipulation that also attenuates salt appetite.

An overview of the HIBISCUS campaign

The EU HIBISCUS project consisted of a series of field campaigns during the intense convective summers in 2001, 2003 and 2004 in the State of São Paulo in Brazil. Its objective was to investigate the impact of deep convection on the Tropical Tropopause Layer (TTL) and the lower stratosphere by providing a new set of observational data on meteorology, tracers of horizontal and vertical transport, water vapour, clouds, and chemistry in the tropical Upper Troposphere/Lower Stratosphere (UT/LS). This was achieved using short duration research balloons to study local phenomena associated with convection over land, and long-duration balloons circumnavigating the globe to study the contrast between land and oceans.Analyses of observations of short-lived tracers, ozone and ice particles show strong episodic local updraughts of cold air across the lapse rate tropopause up to 18 or 19 km (420-440 K) in the lower stratosphere by overshooting towers. The long duration balloon and satellite measurements reveal a contrast between the composition of the lower stratosphere over land and oceanic areas, suggesting significant global impact of such events. The overshoots are shown to be well captured by non-hydrostatic meso-scale Cloud Resolving Models indicating vertical velocities of 50-60 m s(-1) at the top of the Neutral Buoyancy Level (NBL) at around 14 km, but, in contrast, are poorly represented by global Chemistry-Transport Models (CTM) forced by Numerical Weather Forecast Models (NWP) underestimating the overshooting process. Finally, the data collected by the HIBISCUS balloons have allowed a thorough evaluation of temperature NWP analyses and reanalyses, as well as satellite ozone, nitrogen oxide, water vapour and bromine oxide measurements in the tropics.

Short-period variation of cosmic-ray intensity and ozone density observed in the stratosphere

The energy deposition by slowing-down of energetic ionizing particles in the atmosphere enhances the production of constituent concentration which perturbs and eventually destroys the ozone (OZ) layer. Near the Brazilian anomaly region the cosmic-ray (CR) intensity varies greatly due to the magnetic activity in that region. In order to study these variations, stratospheric balloons were launched to measure, simultaneously, the CR and OZ fluxes in the atmosphere. The Fourier-analysed data collected during the flight on April 22, 1989 show evidences of a short-period variation for both fluxes measured. Attempts to verify the physical mechanisms which associate the CR change with the OZ one are not conclusive due to limited data observed on that event. © 1993 Società Italiana di Fisica.

The balloon flights in the tropics of the hibiscus project

HIBISCUS is a project for studying the dynamics, microphysics and chemistry of the Tropical Tropopause Layer based on balloon measurements. Thirteen heavy sondes and 18 short duration balloons of different types have been used for local process studies. Eight superpressure (BP) and 3 Infra Red Montgolfier (MIR) long duration balloons have been flown for extending the investigations at global scale around the world. Overall the campaign has been very successful operationally as well as scientifically. The paper provides a description of the balloons, the instruments and the strategy used for meeting at best the goals of the project.

Would right atrial stretch inhibit sodium intake following GABAA receptor activation in the lateral parabrachial nucleus?

The knowledge of the mechanisms underlying circulating volume control may be achieved by stretching a balloon placed at the junction of the superior vena cava-right atrial junction (SVC-RAJ). We investigated whether the inflation of a balloon at the SVC-RAJ inhibits the intake of 0.3M NaCl induced by GABAA receptor activation in the lateral parabrachial nucleus (LPBN) in euhydrated and satiated rats. Male Wistar rats (280-300g) with bilateral stainless steel LPBN cannulae and balloons implanted at the SVC-RAJ were used. Bilateral injections of the GABAA receptor agonist muscimol (0.5ηmol/0.2l) in the LPBN with deflated balloons increased intake of 0.3M NaCl (30.1±3.9 vs. saline: 2.2±0.7)ml/210min, n=8) and water (17.7±1.9 vs. saline: 2.9±0.5ml/210min). Conversely, 0.3M NaCl (27.8±2.1ml/210min) and water (22.8±2.3ml/210min) intake were not affected in rats with inflated balloons at the SVC-RAJ. The results show that sodium and water intake induced by muscimol injected into the LPBN was not affected by balloon inflation at the SVC-RAJ. We suggest that the blockade of LPBN neuronal activity with muscimol injections impairs inhibitory mechanisms activated by signals from cardiopulmonary volume receptors determined by balloon inflation. © 2013 The Authors.

Quadrinhos na educação: uma proposta didática na educação básica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Um estudo da arte-sequencial: os componentes imagéticos e textuais em homem-aranha : azul

Comic books, graphic narrative and sequential art, had their origin in newspapers, in the period of the Industrial Revolution. First published weekly in the comic strip format, with the passage of time, the new form of literature has gained more and more public and comic strips became complete stories in the format of comic books and later, graphic novels. This course's final paper aims to present the main components of comics: the picture and the text; and to examine the way in which these two elements overlap and complement each other in the configuration of comics as a whole. As the object of analysis, it was chosen the graphic novel Spider-Man: Blue, first published in 2002 as part of a project composed by three other titles from the double winning cartoonists of the Eisner Award, Jeph Loeb and Tim Sale. For theoretical background, was chosen the book Os Quadrinhos - Linguagem e Semiótica: Um Estudo Abrangente da Arte Sequencial written by the researcher Antonio Luiz Cagnin, which presents a study of all components found in the sequential art and treated in this work: the narrative time, visual plans, balloons, caption, and onomatopoeia