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Search Results: 1 - 10 of 699049 matches for " Davi S. B.;Müller "
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Isolation, X-ray crystal structure and theoretical calculations of the new compound 8-Eepicordatin and identification of others terpenes and steroids from the bark and leaves of Croton palanostigma Klotzsch
Brasil, Davi S. B.;Müller, Adolfo H.;Guilhon, Gisele M. S. P.;Alves, Cláudio N.;Peris, Gabriel;Llusar, Rosa;Moliner, Vicent;
Journal of the Brazilian Chemical Society , 2010, DOI: 10.1590/S0103-50532010000400021
Abstract: phytochemical studies of the bark and leaves of croton palanostigma klotzsch (euphorbiaceae) led to the isolation of a new clerodane diterpene, 8-epicordatin (2), in addition to 12-oxohardwickiic acid methyl ester (3), aparisthman, cordatin (1), ent-trachyloban-18-oic acid, ent-13-epimanoyl oxide, ent-3-oxo-13-epimanoyl oxide, ent-3β-hydroxy-13-epimanoyl oxide, sitosterol, stigmasterol, stigmastan-3-one, 6β-hydroxystigmast-4-en-3-one, 6β-hydroxystigmasta-4,22-dien-3-one, stigmast-4-en-3-one, stigmasta-4,22-dien-3-one, 3-o-acetylaleuritolic acid, 11α-hydroxyurs-12-en-3-one, α-amyrenone, 24-methylenecycloartenone and lupenone. these compounds were isolated using typical phytochemical procedures and the structures were deduced from spectroscopic studies, including 2d nmr experiments. in addition, the crystalline structure of 8-epicordatin (2) was determined by x-ray diffraction. nmr theoretical calculations at the b3pw91/dgdzvp level were used to confirm the assignment of the chemical shifts of the h-7α and h-7β hydrogens of 8-epicordatin.
Estudos farmacognósticos, fitoquímicos, atividade antiplasmódica e toxicidade em Artemia salina de extrato etanólico de folhas de Montrichardia linifera (Arruda) Schott, Araceae
Costa, Eliene S. S.;Dolabela, Maria Fani;Póvoa, Marinete M.;Oliveira, Davi J.;Müller, Adolfo H.;
Revista Brasileira de Farmacognosia , 2009, DOI: 10.1590/S0102-695X2009000600006
Abstract: the present paper describes results of a pharmacognostic, a preliminary phytochemical study, brine shrimp toxicity and antiplasmodic activity in a strain of plasmodium falciparum that is resistant to chloroquine (w2) using ethanolic extract obtained from powder of the leaves of montrichardia linifera (arruda) schott, araceae. to perform the pharmacognostic studies methodologies employed in the brazilian pharmacopoea were utilized. the methods described by mattos were utilized for phytochemical prospecting. in the antiplasmodic test the traditional microtest was employed, as well as in the test with brine shrimp. the results obtained in the pharmacognostic studies with the powder from m. linifera leaves showed that it was a moderate thick powder, with water and ash totals within acceptable limits, low density (0.324 and 0.339 g/ml), ph close to neutral (6.69 ± 0.02). preliminary phytochemical analysis showed the presence of alkaloids, flavonoids, tannins, triterpenes and esters. the ethanolic extract from m. linifera leaves presented moderate antiplasmodic activity and low brine shrimp toxicity. to summarize, the powder used in preparing the extract presented good quality in pharmacognostic terms.
Children Safety Devices in Brazil—Why Do People Don’t Use Them after the Law?  [PDF]
S. C. V. Abib, A. M. Fran?óia, F. Ricci, M. V. B. Cezillo, B. R. Müller
Journal of Transportation Technologies (JTTs) , 2014, DOI: 10.4236/jtts.2014.43021
Abstract:

Introduction: Children safety car devices decrease injuries and death in children. A survey conducted in Brazil in 2009 revealed that only 36.1% of children safely transported. In 2010, a Brazilian law was implemented, obligating the use of safety devices. The aim of this study is to evaluate the use of such devices after the law and the eventual reasons for non-use. Methods: A significant sample of Brazilian population aged 18 years or more, which normally carry children until 10 years old answered a survey between August 16 and 25, 2012. The study was conducted in two phases. The first one aimed to raise the proportion and profile of the target population, while the second investigated the children car safety device use (or not). Results: 622 interviews. Children’s transporters are young males (57%), living in a metropolitan area in the South region, concerned about safety and law supervision, with greater education level and income than non-transporters (31%) who are male with lack of information, living in a non-metropolitan area of the Northeast region that would be motivated to use the device by effective law fiscalization or threat of an accident. Conclusion: Two years after the law it is observed that education, income, age, gender and region of origin influence the use/non-use of the safety seats in Brazil. The accident threat and fiscalization are the main reasons for using the device, showing that the lack of information impairs the democratization of its use and the prevention culture has to be enhanced in the country.

The Partition Function in the Wigner-Kirkwood expansion
S. G. Matinyan,B. Müller
Physics , 2006, DOI: 10.1088/0305-4470/39/18/L05
Abstract: We study the semiclassical Wigner-Kirkwood (WK) expansion of the partition function $Z(t)$ for arbitrary even homogeneous potentials, starting from the Bloch equation. As is well known, the phase-space kernel of $Z$ satisfies the so-called Uhlenbeck-Beth equation, which depends on the gradients of the potential. We perform a chain of transformations to obtain novel forms of this equation that invite analogies with various physical phenomena and formalisms, such as diffusion processes, the Fokker-Planck equation, and supersymmetric quantum mechanics.
What Does a First Order Model Tell Us about PEEP Wave Maneuvers?  [PDF]
B. Laufer, J. Kretschmer, P. D. Docherty, Y. S. Chiew, K. Mller
Journal of Biomedical Science and Engineering (JBiSE) , 2017, DOI: 10.4236/jbise.2017.105B008
Abstract:
Patients with acute respiratory distress syndrome (ARDS) are currently treated with a lung protective ventilation strategy and the application of positive end-expiratory pressure (PEEP), sometimes in combination with recruitment maneuvers. In this study, the respiratory system elastance and airway resistance of each breath before, during and after a specific recruitment maneuver (PEEP wave maneuver) were analyzed in two patient groups, ARDS and control group. A reduction of elastance after the maneuver was observed in ARDS patients. In addition, only healthy lungs exhibited a reduction of the elastance during the course of the maneuver, while the lungs of ARDS patients didn’t show that reduction of elastance. The capability of PEEP wave maneuvers to improve lung ventilation was shown and the dynamic behavior of the elastance after the maneuver was illustrated. Healthy lungs adapt faster to changes in mechanical ventilation than the lungs of ARDS patients.
Chaotic Quantization of Classical Gauge Fields
T. S. Biro,S. G. Matinyan,B. Müller
Physics , 2001, DOI: 10.1023/A:1015565621215
Abstract: We argue that the quantized non-Abelian gauge theory can be obtained as the infrared limit of the corresponding classical gauge theory in a higher dimension. We show how the transformation from classical to quantum field theory emerges and calculate Planck's constant from quantities defined in the underlying classical gauge theory.
Quantum Dynamics from Classical Dissipative Systems
T. S. Biró,S. G. Matinyan,B. Müller
Physics , 1999,
Abstract: We argue that the quantized non-Abelian gauge theory can be obtained as the infrared limit of the corresponding classical gauge theory in a higher dimension. We show how the transformation from classical to quantum dynamics emerges and calculate Planck's constant from quantities defined in the underlying classical field theory.
Anomalous viscosity of an expanding quark-gluon plasma
Asakawa, M.;Bass, S. A.;Müller, B.
High Energy Physics - Phenomenology , 2007, DOI: 10.1088/0954-3899/34/8/S108
Abstract: We argue that an expanding quark-gluon plasma has an anomalous viscosity, which arises from interactions with dynamically generated colour fields. The anomalous viscosity dominates over the collisional viscosity for large velocity gradients or weak coupling. This effect may provide an explanation for the apparent near perfect liquidity of the matter produced in nuclear collisions at RHIC without the assumption that it is a strongly coupled state.
The 1986–1989 ENSO cycle in a chemical climate model
S. Br?nnimann,M. Schraner,B. Müller,A. Fischer
Atmospheric Chemistry and Physics Discussions , 2006,
Abstract: A pronounced ENSO cycle occurred from 1986 to 1989, accompanied by distinct dynamical and chemical anomalies in the global troposphere and stratosphere. Reproducing these effects with current climate models not only provides a model test but also contributes to our still limited understanding of ENSO's effect on stratosphere-troposphere coupling. We performed several sets of ensemble simulations with a chemical climate model (SOCOL) forced with global sea surface temperatures. Results were compared with observations and with large-ensemble simulations performed with an atmospheric general circulation model (MRF9). We focus our analysis on the extratropical stratosphere and its coupling with the troposphere. In this context, the circulation over the North Atlantic sector is particularly important. Observed differences between the El Ni o winter 1987 and the La Ni a winter 1989 include a negative North Atlantic Oscillation index with corresponding changes in temperature and precipitation patterns, a weak polar vortex, a warm Arctic middle stratosphere, negative and positive total ozone anomalies in the tropics and at middle to high latitudes, respectively, as well as anomalous upward and poleward Eliassen-Palm (EP) flux in the midlatitude lower stratosphere. Most of the tropospheric features are well reproduced in the ensemble means in both models, though the amplitudes are underestimated. In the stratosphere, the SOCOL simulations compare well with observations with respect to zonal wind, temperature, EP flux, and ozone, but magnitudes are underestimated in the middle stratosphere. The polar vortex strength is well reproduced, but within-ensemble variability is too large for obtaining a significant signal in Arctic temperature and ozone. With respect to the mechanisms relating ENSO to stratospheric circulation, the results suggest that both, upward and poleward components of anomalous EP flux are important for obtaining the stratospheric signal and that an increase in strength of the Brewer-Dobson circulation is part of that signal.
Anomalous viscosity of an expanding quark-gluon plasma
M. Asakawa,S. A. Bass,B. Müller
Physics , 2007, DOI: 10.1088/0954-3899/34/8/S108
Abstract: We argue that an expanding quark-gluon plasma has an anomalous viscosity, which arises from interactions with dynamically generated colour fields. The anomalous viscosity dominates over the collisional viscosity for large velocity gradients or weak coupling. This effect may provide an explanation for the apparent near perfect liquidity of the matter produced in nuclear collisions at RHIC without the assumption that it is a strongly coupled state.
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