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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.
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.
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.
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 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.
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.
65Zn2+ transport by isolated gill epithelial cells of the American lobster, Homarus americanus
Sa M.G.; Ahearn G.A.; Zanotto F.P. (2009)
Gills are the first site of impact by metal ions in contaminated waters. Work on whole gill cells and metal uptake has not been reported before in crustaceans. In this study, gill filaments of the American lobster, Homarus americanus, were dissociated in physiological saline and separated into several cell types on a 30, 40, 50, and 80% sucrose gradient. Cells from each sucrose solution were separately resuspended in physiological saline and incubated in 65Zn2+ in order to assess the nature of metal uptake by each cell type. Characteristics of zinc accumulation by each kind of cell were investigated in the presence and absence of 10 mM calcium, variable NaCl concentrations and pH values, and 100 μM verapamil, nifedipine, and the calcium ionophore A23187. 65Zn2+ influxes were hyperbolic functions of zinc concentration (1-1,000 μM) and followed Michaelis-Menten kinetics. Calcium reduced both apparent zinc binding affinity (K m) and maximal transport velocity (J max) for 30% sucrose cells, but doubled the apparent maximal transport velocity for 80% sucrose cells. Results suggest that calcium, sodium, and protons enter gill epithelial cells by an endogenous broad-specificity cation channel and trans-stimulate metal uptake by a plasma membrane carrier system. Differences in zinc transport observed between gill epithelial cell types appear related to apparent affinity differences of the transporters in each kind of cell. Low affinity cells from 30% sucrose were inhibited by calcium, while high affinity cells from 80% sucrose were stimulated. 65Zn2+ transport was also studied by isolated, intact, gill filament tips. These intact gill fragments generally displayed the same transport properties as did cells from 80% sucrose and provided support for metal uptake processes being an apical phenomenon. A working model for zinc transport by lobster gill cells is presented. © 2009 Springer-Verlag.
A 3D study of the contact interface behavior using elastic-plastic constitutive equations
Bandeira A.A.; Pimenta P.M.; Wriggers P. (2006)
In this work a homogenization method presented by Bandeira et al [2,3,4] is enhanced in order to obtain by numerical simulation the interface law for the normal contact pressure based on statistical surface models. For this purpose elasticplastic behavior of the asperities is considered. Statistical evaluations of numerical simulations lead to a constitutive law for the contact pressure. The resulting law compared with other laws stemming from analytical investigations, like those presented by Greenwood Williamson [11] and Yovanovich [19, 32]. The non-penetration condition and the interface model for contact that takes into account the surface microstructure are investigated in detail. © Springer 2006.
A 4-year follow-up study of attention-deficit hyperactivity symptoms, comorbidities, and psychostimulant use in a Brazilian sample of children and adolescents with attention-deficit/hyperactivity disorder
Palma S.M.M.; Natale A.C.M.P.; Calil H.M. (2015)
© 2015 Palma, Natale and Calil.The aim of this study was to evaluate symptom persistence in attention-deficit/hyperactivity disorder (ADHD), the development of comorbidities, and psychostimulant usage patterns. Follow-up studies were conducted in 37 patients with ADHD and 22 healthy controls, aged 10 and 18, 4 years after their first assessment. The ADHD was rated as persistent if participants met all DSM-IV criteria for syndromic or sub-threshold persistence, or had functional impairments (functional persistence). Of the 37 ADHD patients we reevaluated, 75% had persistent symptoms, and psychiatric comorbidities with additional functional impairments and academic problems were more common than in controls. These follow-up findings show a high comorbidity associated with ADHD and support the importance of evaluation and treatment for ADHD and comorbidities throughout life.
A batch injection analysis system for ascorbic acid determination using amperometric detection on a sessile mercury drop electrode
De Donato A.; Pedrotti J.J.; Gutz I.G.R. (1999)
A batch injection analysis (BIA) system, which uses an automatic mercury electrode (AME) as an amperometric detector, is described. The capillary of this AME was adapted in an inverted position through the bottom of a simple cylindrical electrochemical cell, in order to generate more stable sessile drops and to grant free access for the tip of the programmable micropipettor. The BIA system was evaluated by using the electrochemical oxidation of L-ascorbic acid to dehydroascorbic acid on the sessile mercury drop electrode. Acetate buffer solution (50 mM, pH 4.8) was used as supporting electrolyte. The working electrode was operated at +0.230 V (vs. Ag/AgCl). The effect of the dispensing rate, of the dispensed volume, of the distance between the mercury drop and the pipettor tip, as well as of the solution level in the cell were evaluated. Injections of 50 μL were suitable to reach a detection limit of about 2.5 μM (450 ppb). At the 50 μM ascorbic acid level, an RSD of 1.6% (N = 35) was observed with or without mercury drop renewal between injections. A frequency of 300 injections per hour may be reached when the drop is renewed sporadically. The new BIA method was applied to the determination of ascorbic acid in packed/canned tropical fruit juices. Selectivity was granted by differential measurements of the peak current before and after exposure of samples to ascorbate oxidase (from cucumber).
A Bayesian Framework for Measuring Association and Its Application to Emotional Dynamics in Web Discourse
Xavier H.S.; Cortiz D.; Silvestrin M.; Freitas A.L.; Morello L.Y.N.; Pantaleao F.N.; do Rego G.G. (2024)
© 2024 Copyright held by the owner/author(s). Publication rights licensed to ACM.This paper introduces a Bayesian framework designed to measure the degree of association between categorical random variables. The method is grounded in the formal definition of variable independence and is implemented using Markov Chain Monte Carlo (MCMC) techniques. Unlike commonly employed techniques in Association Rule Learning, this approach enables a clear and precise estimation of confidence intervals and the statistical significance of the measured degree of association. We applied the method to non-exclusive emotions identified by annotators in 4,613 tweets written in Portuguese. This analysis revealed pairs of emotions that exhibit associations and mutually opposed pairs. Moreover, the method identifies hierarchical relations between categories, a feature observed in our data, and is utilized to cluster emotions into basic-level groups.
A betabaculovirus encoding a gp64 homolog
Ardisson-Araujo D.M.P.; Pereira B.T.; Melo F.L.; Ribeiro B.M.; Bao S.N.; Zanotto P.M.A.; Moscardi F.; Kitajima E.W.; Sosa-Gomez D.R.; Wolff J.L.C. (2016)
© 2016 Ardisson-Araújo et al.Background: A betabaculovirus (DisaGV) was isolated from Diatraea saccharalis (Lepidoptera: Crambidae), one of the most important insect pests of the sugarcane and other monocot cultures in Brazil. Results: The complete genome sequence of DisaGV was determined using the 454-pyrosequencing method. The genome was 98,392 bp long, which makes it the smallest lepidopteran-infecting baculovirus sequenced to date. It had a G + C content of 29.7 % encoding 125 putative open reading frames (ORF). All the 37 baculovirus core genes and a set of 19 betabaculovirus-specific genes were found. A group of 13 putative genes was not found in any other baculovirus genome sequenced so far. A phylogenetic analysis indicated that DisaGV is a member of Betabaculovirus genus and that it is a sister group to a cluster formed by ChocGV, ErelGV, PiraGV isolates, ClanGV, CaLGV, CpGV, CrleGV, AdorGV, PhopGV and EpapGV. Surprisingly, we found in the DisaGV genome a G protein-coupled receptor related to lepidopteran and other insect virus genes and a gp64 homolog, which is likely a product of horizontal gene transfer from Group 1 alphabaculoviruses. Conclusion: DisaGV represents a distinct lineage of the genus Betabaculovirus. It is closely related to the CpGV-related group and presents the smallest genome in size so far. Remarkably, we found a homolog of gp64, which was reported solely in group 1 alphabaculovirus genomes so far.
A betabaculovirus-encoded gp64 homolog codes for a functional envelope fusion protein
Ardisson-Araujo D.M.P.; Melo F.L.; Clem R.J.; Wolff J.L.C.; Ribeiro B.M. (2016)
© 2016, American Society for Microbiology.The GP64 envelope fusion protein is a hallmark of group I alphabaculoviruses. However, the Diatraea saccharalis granulovirus genome sequence revealed the first betabaculovirus species harboring a gp64 homolog (disa118). In this work, we have shown that this homolog encodes a functional envelope fusion protein and could enable the infection and fusogenic abilities of a gp64-null prototype baculovirus. Therefore, GP64 may complement or may be in the process of replacing F protein activity in this virus lineage.
A biogeographic and evolutionary analysis of the flora of the North-eastern cerrado, Brazil
Vieira L.T.A.; Castro A.A.J.F.; Coutinho J.M.C.P.; de Sousa S.R.; de Farias R.R.S.; Castro N.M.C.F.; Martins F.R. (2019)
© 2019, © 2019 Botanical Society of Scotland and Taylor & Francis.Background: The forest-savanna habitat switching is thought to have been a recurrent event in evolutionary history. Notwithstanding, the centre of the Cerrado, a large biogeographic domain, may be hypothesised to be a region with historical climatic stability and thus is predicted to contain high richness of cerrado species and the presence of few species from adjacents domains. Aims: We tested if today’s flora of the north-eastern cerrado (NC), a peripheral province of the domain, demonstrated an observable gradient in their distribution from centre of the Cerrado towards adjacents domains. Methods: We compiled vegetation survey data for 178 sites in the cerrado of north-eastern Brazil. Distribution patterns of plant taxa were assessed using multivariate techniques. Results: We recorded 1071 species in 390 genera and 85 families. Almost 40% were monogeneric families and ca. 50% were monospecific genera. The species composition in the NC followed a gradient related to the distance from the centre of the Cerrado towards its periphery. Conclusions: We show that the NC flora is unique and much richer than previously thought and that it is likely to be an outcome of evolutionary processes and of today’s intermixing of species from adjacent formations.

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