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1,8-Cineole induces relaxation in rat and guinea-pig airway smooth muscle
Nascimento N.R.F.; Refosco R.M.D.C.; Vasconcelos E.C.F.; Kerntopf M.R.; Santos C.F.; Batista F.J.A.; De Sousa C.M.; Fonteles M.C. (2009)
Objectives: 1,8-Cineole is a monoterpene with anti-inflammatory, vascular and intestinal smooth muscle relaxant activity. We have evaluated the potential bronchodilatatory activity of this compound. Methods: 1,8-Cineole was tested against carbachol, histamine, K+ 80 mM and ovalbumin-induced bronchial contractions in Wistar rat or guinea-pig tissues. Some of the guinea-pigs had been previously sensitized with an intramuscular injection of 5% (w/v) ovalbumin/saline solution. Control animals received 0.3 ml saline. In separate experimental groups the response to 1,8-cineole (1-30 mg/kg), phenoterol (0.05-5 mg/kg) or vehicle (0.3% Tween in saline) was studied. Key findings: 1,8-Cineole decreased, in vivo, rat bronchial resistance with similar efficacy as phenoterol (66.7 ± 3.2% vs 72.1 ± 5.3%). On the other hand, the maximal relaxant response to 1,8-cineole in carbachol-precontracted rat tracheas was 85.5 ± 5.7% (IC50 = 408.9 (328-5196) μg/ml) compared with 80.2 ± 4.8% (IC50 = 5.1 (4.3-6.1) μg/ml) with phenoterol. The addition of 1,8-cineole to guinea-pig tracheal rings tonically contracted with K+ 80 mM induced a concentration-related relaxation. The maximal relaxation elicited by 1,8-cineole was 113.6 ± 11.7% (IC50 127.0 (115.9-139.2) μg/ml) compared with 129.7 ± 14.6% (IC50 0.13 (0.12-0.14) μg/ml) achieved after phenoterol administration. In addition, the incubation of tracheal rings with 1,8-cineole (100, 300 or 1000 μg/ml), 15 min before inducing phasic contractions with K+ 80 mM, decreased the maximal amplitude of the contraction by 31.6 ± 4.6, 75.7 ± 2.7 and 92.2 ± 1.5%, respectively. In another set of experiments, neither the maximal response nor the IC50 for the 1,8-cineole-induced relaxation were different between normal and ovalbumin-sensitized tissues. Moreover, the relaxation of bronchial rings contracted after exposure to 1 μg/ml ovalbumin occurred at a faster rate in rings pre-incubated with 1,8-cineole when compared with rings pre-incubated with vehicle only (Tween 0.3%). Therefore, in the first minute after the antigen challenge, the tracheal tissue relaxed after the peak contraction by 6.5, 21.4 (P < 0.05 vs control) and 66.9% (P < 0.05 vs control) in the presence of 100, 300 or 1000 μg/ml 1,8-cineole, respectively. Conclusions: 1,8-Cineole relaxed rat and guinea-pig (nonsensitized and ovalbumin-sensitized) airway smooth muscle by a nonspecific mechanism. © 2009 The Authors.
13C NMR spectroscopy of monoterpenoids
Ferreira M.J.P.; Emerenciano V.P.; Linia G.A.R.; Romoff P.; Macari P.A.T.; Rodrigues G.V. (1998)
200-fs mode-locked Erbium-doped fiber laser by using mechanically exfoliated MoS2 saturable absorber onto D-shaped optical fiber
Aiub E.J.; Steinberg D.; Thoroh De Souza E.A.; Saito L.A.M. (2017)
© 2017 Optical Society of America.For the first time, we demonstrated the fabrication of mechanically exfoliated molybdenum disulfide (MoS2) samples deposited onto a D-shaped optical fiber. The MoS2 exfoliated flakes were deposited onto a stacked of 1.2 μm PVA (polyvinyl alcohol) and 300 nm PMMA (polymethyl methacrylate) layers and then transferred directly onto a side polished surface of D-shaped optical fiber with polishing length of 17 mm and no distance from the fiber core. The sample exhibited a high polarization performance as a polarizer with relative polarization extinction ratio of 97.5%. By incorporating the sample as a saturable absorber in the Erbium-doped fiber laser (EDFL), bandwidth of 20.5 nm and pulse duration of 200 fs were generated, which corresponded to the best mode-locking results obtained for all-fiber MoS2 saturable absorber at 1.5 μm wavelength.
22.2-GHz high emission nebulosities associated with the Carina Nebula central region
Scalise Jr. E.; Kaufmann P.; Alcina Braz M. (1974)
MAPS of Carina Nebula, obtained at relatively low frequencies, have shown that most of the radiation arises from a central region and has a simple double structure, separated by about 9.4′. Gardner et al.1 studied Carina Nebula at 5 GHz, the highest frequency so far used, with the Parkes radio telescope and observed a beamwidth of 4′. © 1974 Nature Publishing Group.
2D nanomaterials saturable absorbers fabrication using the droplet method for Erbium-doped fiber lasers
Gerosa R.M.; Steinberg D.; Marcondes R.L.; Domingues S.H.; Saito L.A.M. (2016)
© 2016 Optical Society of America.We present the simple and powerful droplet method to fabricate liquid exfoliated graphene oxide, reduced graphene oxide and black phosphorus polymer-based samples as all-fiber saturable absorbers for ultrashort pulse generation in Erbium-doped fiber lasers.
2D nanomaterials saturable absorbers fabrication using the droplet method for erbium-doped fiber lasers
Gerosa R.M.; Steinberg D.; Marcondes R.L.; Domingues S.H.; Saito L.A.M. (2016)
© 2016 OSA.We present the simple and powerful droplet method to fabricate liquid exfoliated graphene oxide, reduced graphene oxide and black phosphorus polymer-based samples as all-fiber saturable absorbers for ultrashort pulse generation in Erbium-doped fiber lasers.
3-D solar atmospheric model over active regions
Seihorst C.L.; Costa J.E.R.; Silva A.V.R. (2005)
We present here the first results of our 3-D solar atmospheric model over active regions based on radio observations. Intense magnetic fields take place in active regions, which may result in a gyro-resonance emission contribution to the brightness temperature observed at radio frequencies. This model considers the temperature and densities (electrons and ions) distributions, as well as the local magnetic 3-D structure. The location of the magnetic field lines was obtained from force-free extrapolation of MDI (SOHO) magnetograms. This procedure yields three cubes with magnetic field intensities, one for each vector component. Magnetic loops are simulated by filling the region around each magnetic field line with densities and temperature values distinct from the quiet solar atmosphere. Thus, the atmospheric region changes where these flux tubes are present. The model, represented by a volume of 500×500×200 arcsec3, has as free parameters: the flux tube distributions of temperature and density, as well the width. For each column of the cube representing the atmosphere, the equations of radiative transport (including bremsstrahlung and gyro-resonance emission) were solved for the brightness temperature at 17 GHz. These brightness temperature of 500×500 arcsec2 were compared with high spatial resolution solar maps at 17 GHz observed by the Nobeyama Radioheliograph (NoRH). The free parameters are varied so as to obtain the best match to the observations. As a result, the observations are repoduced by an active region model with maximum brightness temperature of 5.2×104 K, magnetic flux tubes with 10 times the local density and 4 times the local temperature below the transition region, and above it, 6 and 2 times the local densities and temperatures, respectively. For this same region, the gyro-resonance emission is negligible compared to the bremsstrahlung contribution, even though the photospheric magnetic field intensities reach 1800 G. The magnetic field contributed mainly for the geometry of the problem.
3-Ishwarone and 3-ishwarol, rare sesquiterpenes in essential oil from leaves of Peperomia oreophila Hensch.
Lago J.H.G.; De Oliveira A.; Guimaraes E.F.; Kato M.J. (2007)
The essential oil from Peperomia oreophila leaves (Piperaceae) was submitted to fractionation in silica gel column. This separation procedure yielded a fraction composed of a hydrocarbon sesquiterpene mixture which was identified as β-elemene, α-ylangene, α-guaiene and β-selinene. Besides, spathulenol and two sesquiterpenes with the rare ishwarane skeleton: 3-ishwarol and 3-ishwarone were also identified. 3-ishwarone was the major component of the crude oil (78% weight). Since the alcohol obtained was not sufficient to allow a complete structural determination, the original ketone was reduced to 3-ishwarol in order to give additional quantities. After the two sesquiterpenes purification, they were characterized by spectrometric techniques (1H-1H COSY, HMQC, HMBC and NOESY). ©2007 Sociedade Brasileira de Química.
300-fs mode-locked Erbium doped fiber laser using evanescent field interaction through graphene oxide saturable absorber in D-shaped fibers
Gerosa R.M.; Steinberg D.; Pellicer F.N.; Domingues S.H.; de Souza E.A.T.; Saito L.A.M. (2016)
© OSA 2016.We report the ultrashort pulse generation of 310 fs from a mode-locked Erbium doped fiber laser using a spin-coated graphene oxide saturable absorber film deposited onto a sidepolished D-shaped optical fiber.
396 fs pulse from an asynchronous mode-locked erbium fiber laser with 2.5-12 GHz repetition rate
Boncristiano E.S.; Saito L.A.M.; De Souza E.A. (2008)
We have demonstrated an Erbium fiber laser hybridly mode-locked by a phase modulator in conjunction with intracavity soliton effect producing pulses as short as 396 fs at 10 GHz. The laser repetition rate is variable from 2 to 12 GHz keeping pulses with duration shorter than 500 fs in this range. © 2008 Wiley Periodicals, Inc.
396 fs, 2.5-12 GHz asynchronous mode-locking erbium fiber laser
Boncristiano E.S.; Saito L.A.M.; De Souza E.A. (2007)
396 fs pulses with adjustable repetition rate from 2.5 GHz to 12 GHz were directly generated by an asynchronous modelocked Er-fiber laser in conjunction with intracavity solitonic effect in a hybrid regime. © 2007 Optical Society of America.
396 fs, 2.5-12 GHz asynchronous mode-locking erbium fiber laser
Boncristiano E.S.; Saito L.A.M.; De Souza E.A. (2007)
396 fs pulses with adjustable repetition rate from 2.5 GHz to 12 GHz were directly generated by an asynchronous modelocked Er-fiber laser in conjunction with intracavity solitonic effect in a hybrid regime. © 2007 Optical Society of America.
3d CFD simulation of vortex-induced vibration of cylinder
Saltara F.; Neto A.D.; Lopez J.I.H. (2011)
The 3D flow around a circular cylinder free to oscillate transversely to the free stream was simulated using ComputationalFluid Dynamics (CFD) and the Spalart-Allmaras Detached Eddy Simulation (DES) turbulence model for a Reynolds numberReD104. Simulations were carried out for a small mass-damping parameter m*ζ=0000858, where m*=3.3 and ζ=000026.We found good agreement between the numerical results and experimental data. The simulations predicted the high observedamplitudes of the upper branch of vortex-induced vibrations for low mass-damping parameters. © by The International Society of Offshore and Polar Engineers.
3D interactive environment applied to fencing training
Guimaraes C.P.; Balbio V.; Cid G.L.; Orselli M.I.V.; Xavier A.P.; Neto A.S.; Correa S.C. (2016)
© Copyright 2016 by SCITEPRESS - Science and Technology Publications, Lda. All rights reserved.The purpose of this study was to present a 3D interactive environment - a Digital Platform to help in fencing training. The first fencing motion described and analysed at the 3D platform was lunge in epee fencing. The platform was able to show kinematic variables of upper and lower limbs and the center of mass that characterized a good performance in epee fencing. The platform also incorporates a digital database of eye track motions of the fencers. An OptiTrack motion capture system was used to capture the lunge motion of five skilled amateur fencing athletes in the presence or not of a static opponent and an Eye Track System Tobbi II was used to track the eye movements of the fencers when performing a lunge attack with a target. The 3D platform was developed using Unity3D and can present some interesting results to improve available information to coaches. That highlights the importance of visualization biomechanical results based on coach criteria in a more understandable way to help athletic training.
3d reconstruction of non-rigid plants and sensor data fusion for agriculture phenotyping
Sampaio G.S.; da Silva L.A.; Marengoni M. (2021)
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.Technology has been promoting a great transformation in farming. The introduction of robotics; the use of sensors in the field; and the advances in computer vision; allow new systems to be developed to assist processes, such as phenotyping, of crop’s life cycle monitoring. This work presents, which we believe to be the first time, a system capable of generating 3D models of non-rigid corn plants, which can be used as a tool in the phenotyping process. The system is composed by two modules: an terrestrial acquisition module and a processing module. The terrestrial acquisition module is composed by a robot, equipped with an RGB-D camera and three sets of temperature, humidity, and luminosity sensors, that collects data in the field. The processing module conducts the non-rigid 3D plants reconstruction and merges the sensor data into these models. The work presented here also shows a novel technique for background removal in depth images, as well as efficient techniques for processing these images and the sensor data. Experiments have shown that from the models generated and the data collected, plant structural measurements can be performed accurately and the plant’s environment can be mapped, allowing the plant’s health to be evaluated and providing greater crop efficiency.
3d transition metal coordination on monolayer MoS2: a facile doping method to functionalize surfaces
Liu H.; Silva W.C.; Santana Goncalves de Souza L.; Veiga A.G.; Seixas L.; Fujisawa K.; Kahn E.; Zhang T.; Zhang F.; Yu Z.; Thompson K.; Lei Y.; de Matos C.J.S.; Rocco M.L.M.; Terrones M.; Grasseschi D. (2022)
© 2022 The Royal Society of Chemistry.Two-dimensional materials (2DM) have attracted much interest due to their distinct optical, electronic, and catalytic properties. These properties can be tuned by a range of methods including substitutional doping and, as recently demonstrated, by surface functionalization with single atoms, thus increasing the 2DM portfolio. We theoretically and experimentally describe the coordination reaction between MoS2 monolayers and 3d transition metals (TMs), exploring their nature and MoS2-TM interactions. Density functional theory calculations, X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) spectroscopy point to the formation of MoS2-TM coordination complexes, where the adsorption energy for 3d TMs resembles the crystal-field (CF) stabilization energy for weak-field complexes. Pearson's theory for hard-soft acid-base and ligand-field theory were used to discuss the periodic trends of 3d TM coordination on MoS2 monolayer surfaces. We found that softer acids with higher ligand field stabilization energy, such as Ni2+, tend to form bonds with more covalent character with MoS2, which can be considered a soft base. On the other hand, harder acids, such as Cr3+, tend to form more ionic bonds. Additionally, we studied the trends in charge transfer and doping observed from XPS and PL results, where metals like Ni led to n-type doping. In contrast, Cu functionalization results in p-type doping. Therefore, the formation of coordination complexes on TMD's surface is a potentially effective way to control and understand the nature of single-atom functionalization of TMD monolayers without relying on or creating new defects.
3α,4α-Epoxy-2-piperidone, a new minor derivative from leaves of Piper crassinervium Kunth (Piperaceae)
Lago J.H.G.; Kato M.J. (2007)
A new antifungal piperidone derivative 3α,4α-epoxy-2- piperidone, whose structure was determined by spectroscopic methods, was isolated from the MeOH extract from leaves of Piper crassinervium. This is the first occurrence of one amide in P. crassinervium.
4.7s nearly periodic oscillations superimposed on the solar microwave great burst of 28 March 1976
Kaufmann P.; Piazza L.R.; Raffaelli J.C. (1977)
An unusual fast oscillation was found superimposed on the solar great burst of 28 March 1976, as measured at 7 GHz. The period of the osculation was 4.7 ± 0.9s, defined over the entire duration of the event. The amplitude of the oscillation was proportional to the flux density, in the range 50 < S < 3000 solar flux units. The degree of circular polarization has not shown any fast periodic time structures. © 1977 D. Reidel Publishing Company.
40 Gb/s RZ DQPSK transmission with SPM and ASE suppression by dispersion management
Susskind S.; De Souza E.A. (2009)
We demonstrate a 40 Gb/s RZ DQPSK single channel transmission over 2900 km of SMF, using a 40 GHz bandwidth optical receiver filter to suppress ASE and improve OSNR. The interaction of SPM and accumulated dispersion is evaluated by minutely system dispersion management. Additionally, we successfully employ a 10 channel DWDM ranging from 1560.20 nm to 1563.86 nm at 40 Gb/s RZ DQPSK and 50 GHz of channel spacing over 1000 km, without raman amplification or special polarization multiplex. ©2009IEEE.
48.8km Ultralong Erbium fiber laser in active mode-locking operation
Saito L.A.M.; Romero M.A.; de Souza E.A. (2010)
By the use of installed fibers inside the city we demonstrated a 48.8 km ultralong Erbium-doped fiber laser in modelocking regime with repetition rate varying from 1-10 GHz. The shortest pulse duration of 42 ps at 2.5 GHz was obtained by optimization of intracavity dispersion. © 2010 The Optical Society of Japan.

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