Estudo do comportamento cortisol, gh e insulina apos uma sessao de exercicio resistido agudo

INTRODUÇÃO:Muitos trabalhos têm estudado o comportamento hormonal nos exercício resistido, entretanto poucos relacionam os hormônios cortisol, GH e insulina.OBJETIVO:Estudar os ajustes das concentrações plasmáticas dos hormônios cortisol, GH e insulina em exercícios resistidos de mesma intensidade com relação à massas musculares distintas.MÉTODOS:Dez voluntários, com 20,3 ± 4,2 anos, 74,1 ± 10,2 kg de peso, 177,2 ± 4,6 cm de estatura e 23,8 ± 3,2 kg/m2 de IMC, realizaram uma sessão de leg press (LP) e supino reto (SR) com quatro séries com 10 repetições a 70% 1 RM com três minutos de intervalo. Foram coletadas amostras de sangue para dosagem das concentrações plasmáticas de cortisol, GH e insulina em repouso (Pré) e em 0' (Rec. 0'), 30' (Rec. 30') e 90' (Rec. 90') de recuperação.RESULTADOS:As concentrações plasmáticas de cortisol foram significativamente reduzidas ao final da recuperação em LP (2,20±0,37 ng/dl para 1,33±0,38ng/dl) em relação à pré-dosagem. As concentrações de GH e insulina elevaram-se significativamente durante a recuperação. GH em LP foi significativamente maior em Rec. 0' (2,75±3,29 ng/ml para 9,60±5,32 ng/dl) do que em pré. A insulina elevou-se significativamente em Rec. 30' em LP (14,70±7,92 ulU/ml para 21,66 ± 8,61 ulU/ml) e em SR (6,17 ± 2,99 ulU/ml para 19,70 ± 13,8 ulU/ml) em relação à pré. As concentrações plasmáticas de insulina pré em LP foram significativamente superiores a SR (14,70 ulU/ml e 6,17 ± 2,99 ulU/ml).CONCLUSÃO:O exercício resistido promoveu diferentes ajustes nas concentrações hormonais de cortisol, GH e insulina durante o período de recuperação.

Free radical entrapment and crystallinity of resin composites after accelerated aging as a function of the expiration date

This study evaluated the spin concentration and the crystallinity in different classifications of dental composites as a function of the material condition (new, aged and expired). Specimens were obtained according to the factors: composites: Filtek P60, Filtek Z250, Filtek Z350XT, and Filtek Silorane; and material conditions: new, aged, and expired. The syringe composites underwent an accelerated aging protocol (Arrhenius model). The magnetic properties of the composites were characterized using Electron Paramagnetic Resonance (EPR) and the concentration of spins (number of spins/mass) was calculated. The crystallinity of the composites tested was characterized with X-ray diffraction (XRD). Filtek P60 and Filtek Z250 presented similarities in terms of spin concentration and crystallinity, irrespective of the material condition. The aging protocol influenced the composite Filmic Z350XT that exhibited a significant increase in the spin concentration. Besides, lower intensity peaks of the organic matrix and amorphous silica were also observed for both aged and expired Filtek Z350XT. Although a significant lower spin concentration was observed for the silorane composite in comparison to that of the methacrylates, a decrease in the relative intensity of peaks of the amorphous region related to the organic components in the diffractograms was observed. The material conditions tested influence the crystallinity and the magnetic properties of the composites evaluated. (C) 2014 Elsevier Ltd. All rights reserved.

Study of K beta X-ray emission spectroscopy applied to Mn((2-x))V((1+x))O4 (x=0 and 1/3) oxyspinel and comparison with XANES

Oxidation state and coordination of transition metal cations seems to be hard to assess when considering multiple cations, each one with different possible oxidation states. In fact, this is the case of the spineltype double oxides family. High resolution K beta X-ray fluorescence spectra were measured in Mn(2-x)V(1+4)O4 (x=0 and 1/3) spinels-type double oxides in order to determine the oxidation state and coordination of V and Mn cations. The relative intensity of radiative Auger effect KM2,3M4,5 to the total intensity and the integral absolute difference value were used as reference parameters for the characterization of Mn oxidation states. The coordination of Mn ions was inferred by the intensity of the K beta(5) line. In the case of V compounds, it was used as the intensity of the line K beta' relative to the total area of K beta region. The obtained results were further compared with X-ray absorption spectra analysis, showing good agreements regarding the oxidation state characterization. However, there were found some discrepancies in coordination, due to customary oversimplifications in the K beta(5) line origin. The obtained results might represent valuable and useful data for chemical scopes of characterizing spineltype oxides family. (C) 2013 Elsevier Ltd. All rights reserved.

Aspectos estruturais e moleculares do músculo cardíaco durante a transição entre a disfunção e a insuficiência cardiaca

Pós-graduação em Biologia Geral e Aplicada - IBB

Aspectos estruturais e moleculares do músculo cardíaco durante a transição entre a disfunção e a insuficiência cardiaca

Pós-graduação em Biologia Geral e Aplicada - IBB

On the nu SiO infrared absorption of polysiloxane films

The infrared absorption of polysiloxanes involves a strong band at around 1050 cm(-1), attributed to the antisymmetric vibration of siloxane bridges. The splitting of this band into two components is generally attributed to coupling between next-neighbor siloxane groups along the polysiloxane chain. From a quantitative analysis of the spectra of these materials, we find that this splitting is larger when the material is in thin-film form, and that the relative intensity of the two components is polarization dependent. We show that these effects are fully understandable in the theoretical framework of infrared absorption by thin films, and are related to long-range dipolar interactions responsible for the longitudinal-transverse splitting effect in crystalline materials. As a consequence, the polarization dependence of the infrared absorption observed for thin films does not appear to be associated with an orientational ordering in the film. (c) 2012 Elsevier B.V. All rights reserved.

SnO2 nanocrystals synthesized by microwave-assisted hydrothermal method: towards a relationship between structural and optical properties

The exploration of novel synthetic methodologies that control both size and shape of functional nanostructure opens new avenues for the functional application of nanomaterials. Here, we report a new and versatile approach to synthesize SnO2 nanocrystals (rutile-type structure) using microwave-assisted hydrothermal method. Broad peaks in the X-ray diffraction spectra indicate the nanosized nature of the samples which were indexed as a pure cassiterite tetragonal phase. Chemically and physically adsorbed water was estimated by TGA data and FT-Raman spectra to account for a new broad peak around 560 cm(-1) which is related to defective surface modes. In addition, the spherical-like morphology and low dispersed distribution size around 3-5 nm were investigated by HR-TEM and FE-SEM microscopies. Room temperature PL emission presents two broad bands at 438 and 764 nm, indicating the existence of different recombination centers. When the size of the nanospheres decreases, the relative intensity of 513 nm emission increases and the 393 nm one decreases. UV-Visible spectra show substantial changes in the optical absorbance of crystalline SnO2 nanoparticles while the existence of a small tail points out the presence of localized levels inside the forbidden band gap and supplies the necessary condition for the PL emission.

Spectroscopic, morphological and electrochromic characterization of layer-by-layer hybrid films of polyaniline and hexaniobate nanoscrolls

The combination of semiconducting oxides and polyaniline in the nanoscale range may result in hybrid materials having enhanced properties, such as electrochromism and charge capacity. This paper reports the spectroscopic, morphological and electrochromic characterization of hybrid films made up of hexaniobate one-dimensional (1D) nanoscrolls and polyaniline prepared by the layer-by-layer assembly technique (LbL). Secondary electron imaging and backscattered electron imaging techniques performed using a scanning electron microscope showed that polyaniline is adsorbed on the hexaniobate nanoscrolls, which confirms the combination of the components in the nanoscale domain. UV-VIS-NIR electronic spectra of the LbL hybrid films showed the absorption tail in the NIR region, assigned to delocalized polarons of the polyaniline. Resonance Raman spectra in the 1000-1700 cm(-1) range indicated that hybrid films present a higher relative intensity of polaron bands at 1337 and 1508 cm(-1) than pristine polyaniline in the emeraldine salt form. These results suggest that hexaniobate nanoscrolls induce a secondary doping of polyaniline. The cyclic voltammetry (CV) data for the hybrid film showed a specific capacity of 870 C cm(-3). According to CV results, the synergistic effect on charge storage properties of the hybrid material is attributed to the enhanced electroactivity of the hexaniobate component in the LbL film. Spectroelectrochemical experiments showed that the electrochromic efficiencies at 420 nm are ca. -41 and 24 cm(2) C-1 as the potential changes from 0.8 to -0.9 V and from -0.9 to -1.8 V, respectively, whereas at 800 nm the efficiencies are ca. -55 and 8 cm(2) C-1 for the same potential ranges. The electrochromic efficiencies and multi-colour character of the LbL film of hexaniobate nanoscrolls and polyaniline indicate that this novel hybrid material is an interesting modified electrode for electrochromic devices.

Non-Linear Pricing in Imperfectly Competitive Markets

This thesis is dedicated to the analysis of non-linear pricing in oligopoly. Non-linear pricing is a fairly predominant practice in most real markets, mostly characterized by some amount of competition. The sophistication of pricing practices has increased in the latest decades due to the technological advances that have allowed companies to gather more and more data on consumers preferences. The first essay of the thesis highlights the main characteristics of oligopolistic non-linear pricing. Non-linear pricing is a special case of price discrimination. The theory of price discrimination has to be modified in presence of oligopoly: in particular, a crucial role is played by the competitive externality that implies that product differentiation is closely related to the possibility of discriminating. The essay reviews the theory of competitive non-linear pricing by starting from its foundations, mechanism design under common agency. The different approaches to model non-linear pricing are then reviewed. In particular, the difference between price and quantity competition is highlighted. Finally, the close link between non-linear pricing and the recent developments in the theory of vertical differentiation is explored. The second essay shows how the effects of non-linear pricing are determined by the relationship between the demand and the technological structure of the market. The chapter focuses on a model in which firms supply a homogeneous product in two different sizes. Information about consumers' reservation prices is incomplete and the production technology is characterized by size economies. The model provides insights on the size of the products that one finds in the market. Four equilibrium regions are identified depending on the relative intensity of size economies with respect to consumers' evaluation of the good. Regions for which the product is supplied in a single unit or in several different sizes or in only a very large one. Both the private and social desirability of non-linear pricing varies across different equilibrium regions. The third essay considers the broadband internet market. Non discriminatory issues seem the core of the recent debate on the opportunity or not of regulating the internet. One of the main questions posed is whether the telecom companies, owning the networks constituting the internet, should be allowed to offer quality-contingent contracts to content providers. The aim of this essay is to analyze the issue through a stylized two-sided market model of the web that highlights the effects of such a discrimination over quality, prices and participation to the internet of providers and final users. An overall welfare comparison is proposed, concluding that the final effects of regulation crucially depend on both the technology and preferences of agents.

Species specific nitrogen isotope analysis by NanoSIMS

Der atmosphärische Kreislauf reaktiver Stickstoffverbindungen beschäftigt sowohl die Naturwissenschaftler als auch die Politik. Dies ist insbesondere darauf zurückzuführen, dass reaktive Stickoxide die Bildung von bodennahem Ozon kontrollieren. Reaktive Stickstoffverbindungen spielen darüber hinaus als gasförmige Vorläufer von Feinstaubpartikeln eine wichtige Rolle und der Transport von reaktivem Stickstoff über lange Distanzen verändert den biogeochemischen Kohlenstoffkreislauf des Planeten, indem er entlegene Ökosysteme mit Stickstoff düngt. Die Messungen von stabilen Stickstoffisotopenverhältnissen (15N/14N) bietet ein Hilfsmittel, welches es erlaubt, die Quellen von reaktiven Stickstoffverbindungen zu identifizieren und die am Stickstoffkeislauf beteiligten Reaktionen mithilfe ihrer reaktionsspezifischen Isotopenfraktionierung genauer zu untersuchen. rnIn dieser Doktorarbeit demonstriere ich, dass es möglich ist, mit Hilfe von Nano-Sekundärionenmassenspektrometrie (NanoSIMS) verschiedene stickstoffhaltige Verbindungen, die üblicherweise in atmosphärischen Feinstaubpartikeln vorkommen, mit einer räumlichen Auflösung von weniger als einem Mikrometer zu analysieren und zu identifizieren. Die Unterscheidung verschiedener stickstoffhaltiger Verbindungen erfolgt anhand der relativen Signalintensitäten der positiven und negativen Sekundärionensignale, die beobachtet werden, wenn die Feinstaubproben mit einem Cs+ oder O- Primärionenstrahl beschossen werden. Die Feinstaubproben können direkt auf dem Probenahmesubstrat in das Massenspektrometer eingeführt werden, ohne chemisch oder physikalisch aufbereited zu werden. Die Methode wurde Mithilfe von Nitrat, Nitrit, Ammoniumsulfat, Harnstoff, Aminosären, biologischen Feinstaubproben (Pilzsporen) und Imidazol getestet. Ich habe gezeigt, dass NO2 Sekundärionen nur beim Beschuss von Nitrat und Nitrit (Salzen) mit positiven Primärionen entstehen, während NH4+ Sekundärionen nur beim Beschuss von Aminosäuren, Harnstoff und Ammoniumsalzen mit positiven Primärionen freigesetzt werden, nicht aber beim Beschuss biologischer Proben wie z.B. Pilzsporen. CN- Sekundärionen werden beim Beschuss aller stickstoffhaltigen Verbindungen mit positiven Primärionen beobachtet, da fast alle Proben oberflächennah mit Kohlenstoffspuren kontaminiert sind. Die relative Signalintensität der CN- Sekundärionen ist bei kohlenstoffhaltigen organischen Stickstoffverbindungen am höchsten.rnDarüber hinaus habe ich gezeigt, dass an reinen Nitratsalzproben (NaNO3 und KNO3), welche auf Goldfolien aufgebracht wurden speziesspezifische stabile Stickstoffisotopenverhältnisse mithilfe des 15N16O2- / 14N16O2- - Sekundärionenverhältnisses genau und richtig gemessen werden können. Die Messgenauigkeit auf Feldern mit einer Rastergröße von 5×5 µm2 wurde anhand von Langzeitmessungen an einem hausinternen NaNO3 Standard als ± 0.6 ‰ bestimmt. Die Differenz der matrixspezifischen instrumentellen Massenfraktionierung zwischen NaNO3 und KNO3 betrug 7.1 ± 0.9 ‰. 23Na12C2- Sekundärionen können eine ernst zu nehmende Interferenz darstellen wenn 15N16O2- Sekundärionen zur Messung des nitratspezifischen schweren Stickstoffs eingesetzt werden sollen und Natrium und Kohlenstoff im selben Feinstaubpartikel als interne Mischung vorliegt oder die natriumhaltige Probe auf einem kohlenstoffhaltigen Substrat abgelegt wurde. Selbst wenn, wie im Fall von KNO3, keine derartige Interferenz vorliegt, führt eine interne Mischung mit Kohlenstoff im selben Feinstaubpartikel zu einer matrixspezifischen instrumentellen Massenfraktionierung die mit der folgenden Gleichung beschrieben werden kann: 15Nbias = (101 ± 4) ∙ f − (101 ± 3) ‰, mit f = 14N16O2- / (14N16O2- + 12C14N-). rnWird das 12C15N- / 12C14N- Sekundärionenverhältnis zur Messung der stabilen Stickstoffisotopenzusammensetzung verwendet, beeinflusst die Probematrix die Messungsergebnisse nicht, auch wenn Stickstoff und Kohlenstoff in den Feinstaubpartikeln in variablen N/C–Verhältnissen vorliegen. Auch Interferenzen spielen keine Rolle. Um sicherzustellen, dass die Messung weiterhin spezifisch auf Nitratspezies eingeschränkt bleibt, kann eine 14N16O2- Maske bei der Datenauswertung verwendet werden. Werden die Proben auf einem kohlenstoffhaltigen, stickstofffreien Probennahmesubstrat gesammelt, erhöht dies die Signalintensität für reine Nitrat-Feinstaubpartikel.

Photon-beam subsource sensitivity to the initial electron-beam parameters

One limitation to the widespread implementation of Monte Carlo (MC) patient dose-calculation algorithms for radiotherapy is the lack of a general and accurate source model of the accelerator radiation source. Our aim in this work is to investigate the sensitivity of the photon-beam subsource distributions in a MC source model (with target, primary collimator, and flattening filter photon subsources and an electron subsource) for 6- and 18-MV photon beams when the energy and radial distributions of initial electrons striking a linac target change. For this purpose, phase-space data (PSD) was calculated for various mean electron energies striking the target, various normally distributed electron energy spread, and various normally distributed electron radial intensity distributions. All PSD was analyzed in terms of energy, fluence, and energy fluence distributions, which were compared between the different parameter sets. The energy spread was found to have a negligible influence on the subsource distributions. The mean energy and radial intensity significantly changed the target subsource distribution shapes and intensities. For the primary collimator and flattening filter subsources, the distribution shapes of the fluence and energy fluence changed little for different mean electron energies striking the target, however, their relative intensity compared with the target subsource change, which can be accounted for by a scaling factor. This study indicates that adjustments to MC source models can likely be limited to adjusting the target subsource in conjunction with scaling the relative intensity and energy spectrum of the primary collimator, flattening filter, and electron subsources when the energy and radial distributions of the initial electron-beam change.

Terrigenous sedimentation of sediment core GeoB6007-2

Variations in deposition of terrigenous fine sediments and their grain-size distributions from a high-resolution marine sediment record offshore northwest Africa (30°51.0'N; 10°16.1'W) document climate changes on the African continent during the Holocene. End-member grain-size distributions of the terrigenous silt fraction, which are related to fluvial and aeolian dust transport, indicate millennial-scale variability in the dominant transport processes at the investigation site off northwest Africa as well as recurring periods of dry conditions in northwest Africa during the Holocene. The terrigenous record from the subtropical North Atlantic reflects generally humid conditions before the Younger Dryas, during the early to mid-Holocene, as well as after 1.3 kyr BP. By contrast, continental runoff was reduced and arid conditions were prevalent at the beginning of the Younger Dryas and during the mid- and late Holocene. A comparison with high- and low-latitude Holocene climate records reveals a strong link between northwest African climate and Northern Hemisphere atmospheric circulation throughout the Holocene. Due to its proximal position, close to an ephemeral river system draining the Atlas Mountains as well as the adjacent Saharan desert, this detailed marine sediment record, which has a temporal resolution between 15 and 120 years, is ideally suited to enhance our understanding of ocean-continent-atmosphere interactions in African climates and the hydrological cycle of northern Africa after the last deglaciation.

Biomarker and x-ray diffraction data from Site U1313 (MIS 16 - 9)

A reconstruction of Milankovitch to millennial-scale variability of sea-surface temperature (SST) and sea-surface productivity in the Pleistocene mid-latitude North Atlantic Ocean (MIS 16-9) and its relationship to ice sheet instability was carried out on sediments from IODP Site U1313. This reconstruction is based on alkenone and n-alkane concentrations, Uk37' index, total organic carbon (TOC) and carbonate contents, X-Ray diffraction (XRD) data, magnetic susceptibility, and accumulation rates. Increased input of ice-rafted debris (IRD) occurred during MIS 16, 12, and 10, characterized by high concentrations of dolomite, quartz, and feldspars and elevated accumulation rates of terrigenous matter. Minimum input values of terrigenous matter, on the other hand, were determined for MIS 13 and 11. Peak values of dolomite, coinciding with quartz, plagioclase, and kalifeldspar peaks and maxima in long-chain n-alkanes indicative for land plants, are interpreted as Heinrich-like Events related to sudden instability of the Laurentide Ice Sheet during early and late (deglacial) phases of the glacials. The coincidence of increased TOC values with elevated absolute concentrations of alkenones suggest increased glacial productivity, probably due to a more southern position of the Polar Front. Alkenone-based SST reached absolute maxima of about 19°C during MIS 11.3 and absolute minima of <10°C during MIS 12 and 10. Within MIS 11, prominent cooling events (MIS 11.22 and 11.24) occurred. The absolute SST minima recorded directly before and after the glacial maxima MIS 10.2 and 12.2, are related to Heinrich-like Event meltwater pulses, as supported by the coincidence of SST minima and maxima in C37:4 alkenones and dolomite. These sudden meltwater pulses - especially during Terminations IV and V - probably caused a collapse of phytoplankton productivity as indicated by the distinct drop in alkenone concentrations. Ice-sheet disintegration and subsequent surges and outbursts of icebergs and meltwater discharge may have been triggered by increased insolation in the Northern High Latitudes.