348 resultados para Chrosomus eos
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Terahertz power transmission spectroscopy (TPTS) measurements have been carried out to detect a difference between the hydration shells of G-quadruplex forming DNA sequences in strand and quadruplex configuration. Evidence of a change in hydration shell was observed.
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Recent studies indicate that magnetopause reconnection can, at times, occur exclusively as a series of separated, short bursts. Reconnection generates “open” magnetic flux that threads the magnetospheric boundary, the magnetopause, and so connects the magnetosphere with interplanetary space. The rate at which open flux is generated by a line of unit length in the magnetopause is called the reconnection rate. By Faraday's induction law, the reconnection rate is a boundary-tangential electric field, Et, along that line (called an X-line).
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The concept of magnetic reconnection originated with the suggestion by Giovanelli [1946] that particles could be energized during solar flares near nulls in the magnetic field. Hoyle [1949] subsequently proposed that such a process could also act at nulls between the geomagnetic field and the interplanetary magnetic field (IMF) to generate the energized particles responsible for auroral displays. However, the idea of the interconnection of the two magnetic fields, as we know it today, was first presented by Hoyle's student, Dungey [1953, 1961].
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A project on sea surface temperature is generating new climate data records from satellite observations. The data are independent of in situ observations and are harmonious across satellite sensors to maximize stability and have realistic, context-sensitive uncertainty estimates at all spatial and temporal scales. The project, part of the European Space Agency Climate Change Initiative (SST CCI), now seeks to establish a useful method for communicating uncertainty in sea surface temperatures. This goal was the impetus for a workshop held in November 2014 in Exeter in the United Kingdom, summarised in this article.
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Aromatherapy uses essential oils (EOs) for several medical purposes, including relaxation. The association between the use of aromas and a decrease in anxiety could be a valuable instrument in managing anxiety in an ever increasing anxiogenic daily life style. Linalool is a monoterpene commonly found as the major volatile component of EOs in several aromatic plant species. Adding to previously reported sedative effects of inhaled linalool, the aim of this study was to investigate the effects of inhaled linalool on anxiety, aggressiveness and social interaction in mice. Additionally, we investigated the effects of inhaled linalool on the acquisition phase of a step-down memory task in mice. Inhaled linalool showed anxiolytic properties in the light/dark test, increased social interaction and decreased aggressive behavior; impaired memory was only seen the higher dose of linalool. These results strengthen the suggestion that inhaling linalool rich essential oils can be useful as a mean to attain relaxation and counteract anxiety. (C) 2009 Elsevier GmbH. All rights reserved.
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O desenvolvimento industrial no Espaço Organizado (EO) tem se dado através de políticas públicas e iniciativas privadas, atendendo, em alguns casos, aos fatores de competitividade para sua respectiva implementação, outras vezes nem tanto. O principal objetivo desse trabalho foi realizar uma análise dos fatores de competitividade dos distritos industriais do Estado do Rio de Janeiro, contribuindo, dessa forma, através dos resultados apresentados ao final do trabalho, para subsidiar novas políticas públicas e/ou suporte às iniciativas privadas, quando da atração, implantação, retenção e ampliação de indústrias e empresas correlacionadas, nesses espaços. A delimitação da amostra dos Espaços Organizados (EOs) foi definida em função da disponibilidade dos dados e homogeneidade da amostra, no caso, distritos industriais no Estado do Rio de Janeiro. Na execução das etapas do projeto para o cumprimento do seu objetivo principal, foram realizadas etapas intermediárias na seguinte forma: identificação da nomenclatura disponível para os tipos de EOs existentes; elaboração de proposta para a caracterização dos EOs; identificação dos fatores de competitividade dos EOs existentes no Estado do Rio de Janeiro; validação desses fatores de competitividade junto ao grupo entrevistado de representantes do governo, municípios, instituições de fomento e executivos das empresas em operação nas áreas estudadas; mapeamento dos EOs existentes no Estado do Rio de Janeiro e análise dos fatores de competitividade desses espaços, com suas correlações quanto a geração de emprego e atração de empresas. Por fim, após análise dos resultados, a discussão e as considerações finais apontaram tendências que poderão ser aprofundadas em futuros trabalhos de apoio na elaboração das estratégias públicas e/ou privadas que visam melhor aproveitamento e utilização dos EOs destinados ao desenvolvimento industrial.
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In this work, experimental data for the system Lippia alba + CO2 is presented. The major constituents of the L. alba volatile oil are limonene and carvone. Thus, literature data for the systems limonene + CO2 and carvone + CO2, and the Peng-Robinson equation of state (PR-EOS) were used to select the operating temperature and pressure, which maximize the global yield in L. alba extract. Global yields were determined at 80, 100, and 120 bar and 40, 45, and 50 degrees C. L. alba extracts were also obtained by conventional processes (hydrodistillation, low-pressure ethanol extraction and Soxhlet ethanol). The chemical compositions of the extracts were determined by gas and thin layer chromatography (TLC). The secretor structures of L. alba were observed by scanning electron microscopy (SEM) before and after supercritical extraction. The largest yield (similar to 7%, mass of extract/mass of dry solid) of the CO2-extract was obtained at 318 K and 100 bar. The chemical compositions of the CO2-extracts were different from those of the extracts obtained by Soxhlet and low-pressure solvent extraction (LPSE) because of the co-extraction of heavy substances by ethanol. The operating conditions that maximized the carvone and limomene yields were 80 bar and 323 K (80 mass%) and 120 bar and 323 K (17 mass%), respectively. (c) 2004 Elsevier B.V All rights reserved.
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The composition of petroleum may change from well to well and its resulting characteristics influence significantly the refine products. Therefore, it is important to characterize the oil in order to know its properties and send it adequately for processing. Since petroleum is a multicomponent mixture, the use of synthetic mixtures that are representative of oil fractions provides a better understand of the real mixture behavior. One way for characterization is usually obtained through correlation of physico-chemical properties of easy measurement, such as density, specific gravity, viscosity, and refractive index. In this work new measurements were obtained for density, specific gravity, viscosity, and refractive index of the following binary mixtures: n-heptane + hexadecane, cyclohexane + hexadecane, and benzene + hexadecane. These measurements were accomplished at low pressure and temperatures in the range 288.15 K to 310.95 K. These data were applied in the development of a new method of oil characterization. Furthermore, a series of measurements of density at high pressure and temperature of the binary mixture cyclohexane + n-hexadecane were performed. The ranges of pressure and temperature were 6.895 to 62.053 MPa and 318.15 to 413.15 K, respectively. Based on these experimental data of compressed liquid mixtures, a thermodynamic modeling was proposed using the Peng-Robinson equation of state (EOS). The EOS was modified with scaling of volume and a relatively reduced number of parameters were employed. The results were satisfactory demonstrating accuracy not only for density data, but also for isobaric thermal expansion and isothermal compressibility coefficients. This thesis aims to contribute in a scientific manner to the technological problem of refining heavy fractions of oil. This problem was treated in two steps, i.e., characterization and search of the processes that can produce streams with economical interest, such as solvent extraction at high pressure and temperature. In order to determine phase equilibrium data in these conditions, conceptual projects of two new experimental apparatus were developed. These devices consist of cells of variable volume together with a analytical static device. Therefore, this thesis contributed with the subject of characterization of hydrocarbons mixtures and with development of equilibrium cells operating at high pressure and temperature. These contributions are focused on the technological problem of refining heavy oil fractions
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Significant observational effort has been directed to unveiling the nature of the so-called dark energy. However, given the large number of theoretical possibilities, it is possible that this a task cannot be based only on observational data. In this thesis we investigate the dark energy via a thermodynamics approach, i.e., we discuss some thermodynamic properties of this energy component assuming a general time-dependent equation-of-state (EoS) parameter w(a) = w0 + waf(a), where w0 and wa are constants and f(a) may assume different forms. We show that very restrictive bounds can be placed on the w0 - wa space when current observational data are combined with the thermodynamic constraints derived. Moreover, we include a non-zero chemical potential μ and a varying EoS parameter of the type ω(a) = ω0 + F(a), therefore more general, in this thermodynamical description. We derive generalized expressions for the entropy density and chemical potential, noting that the dark energy temperature T and μ evolve in the same way in the course of the cosmic expansion. The positiveness of entropy S is used to impose thermodynamic bounds on the EoS parameter ω(a). In particular, we find that a phantom-like behavior ω(a) < −1 is allowed only when the chemical potential is a negative quantity (μ < 0). Thermodynamically speaking, a complete treatment has been proposed, when we address the interaction between matter and energy dark
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The aim of this study was to analyze the color alterations performed by the CIE L*a*b* system in the digital imaging of shade guide tabs, which were obtained photographically according to the automatic and manual modes. This study also sought to examine the observers' agreement in quantifying the coordinates. Four Vita Lumin Vaccum shade guide tabs were used: A3.5, B1, B3 and C4. An EOS Canon digital camera was used to record the digital images of the shade tabs, and the images were processed using Adobe Photoshop software. A total of 80 observations (five replicates of each shade according to two observers in two modes, specifically, automatic and manual) were obtained, leading to color values of L*, a* and b*. The color difference (AE) between the modes was calculated and classified as either clinically acceptable or unacceptable. The results indicated that there was agreement between the two observers in obtaining the L*, a* and b* values related to all guides. However, the B1, B3, and C4 shade tabs had AE values classified as clinically acceptable (Delta E = 0.44, Delta E = 2.04 and Delta E = 2.69, respectively). The A3.5 shade tab had a AE value classified as clinically unacceptable (Delta E = 4.17), as it presented higher values for luminosity in the automatic mode (L* = 54.0) than in the manual mode (L* = 50.6). It was concluded that the B1, B3 and C4 shade tabs can be used at any of the modes in digital camera (manual or automatic), which was a different finding from that observed for the A3.5 shade tab.
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The use of essential oils (EOs) in functional foods containing probiotic microorganisms must consider the antimicrobial activity of these oils against beneficial bacteria such as Lactobacillus rhamnosus. This study aimed to evaluate the sensitivity of L. rhamnosus cultures treated with cinnamon EO through viable cell counts and visualisation by transmission electron microscopy. Cinnamon EO at a concentration of 0.04% had a bacteriostatic activity after 2 h of incubation. Although slight alterations were detected in the cell structure, this concentration was considered to be bactericidal, since it led to a significant reduction in cell numbers after 24 h. on the other hand, cinnamon EO at a 1.00% concentration decreased cell counts by 3 log units after 2 h incubation and no viable cell count was detected after 24 h. Transmission electron microscopy indicated that cells treated with 1.00% cinnamon EO were severely damaged and presented cell membrane disruption and cytoplasmic leakage.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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We aimed to establish a phytochemical analysis of the crude extracts and performed GC-MS of the essential oils (EOs) of Eugenia uniflora L. (Myrtaceae) and Asteraceae species Baccharis dracunculifolia DC, Matricaria chamomilla L. and Vernonia polyanthes Less, as well as determining their antimicrobial activity. Establishment of the minimal inhibitory concentrations of the crude extracts and EOs against 16 Staphylococcus aureus and 16 Escherichia coli strains from human specimens was carried out using the dilution method in Mueller-Hinton agar. Some phenolic compounds with antimicrobial properties were established, and all EOs had a higher antimicrobial activity than the extracts. Matricaria chamomilla extract and E. uniflora EO were efficient against S. aureus strains, while E. uniflora and V. polyanthes extracts and V. polyanthes EO showed the best antimicrobial activity against E. coli strains. Staphylococcus aureus strains were more susceptible to the tested plant products than E. coli, but all natural products promoted antimicrobial growth inhibition.
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We derive the equation of state (EOS) for electrically charged neutral dense matter using the quantum hadrodynamics (QHD) model. This is carried out in a non-perturbative manner including quantum corrections for baryons through a realignment of vacuum with baryon-antibaryon condensates. This yields the results of relativistic Hartree approximation of summing over baryonic tadpole diagrams. The quantum corrections from the scalar meson is also taken into account in a similar way. This leads to a softening of the EOS for the hyperonic matter. The formalism also allows Lis to make a self-consistent calculation of the in-medium sigma meson mass. The effects of such quantum corrections on the composition of charged neutral dense matter is considered. The effect of the resulting EOS on the structure of neutron stars is also studied.
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Thirty-two Polwarth sheep of ages up to 1 year were observed under temperatures varying from 10.5 to 46.5°C. The following blood cell counts were made: erythrocyte (RBC), leucocyte (WBC), eosinophil (EOS), neutrophil (NEU), lymphocyte (LYM) and monocyte (MON). Other traits measured were: haemoglobin (HB), haematocrit (HT), blood glucose (GLU) and serum protein (PROT). Multivariate analysis of variance was used and the results showed a significant (P<0.001) effect for the interaction of shearing and temperature treatment. Under temperatures >25°C, sheep presented a decrease of RBC, WBC, HB and HT, these differences being greater in the shorn than in the unshorn animals. Unshorn animals presented higher variations in EOS, NEU, LYM, MON and GLU. Blood glucose increased under high temperatures in the shorn animals (from 56.36±0.65 mg/100 ml to 60.52±0.69 mg/100 ml) as in the unshorn animals (from 54.72±0.74 mg/100 ml to 57.56±0.77 mg/100 ml). © 1992 International Society of Biometeorology.