Search results for "clase"

Pharmacological profile of phytoestrogens in cerebral vessels: in vitro study with rabbit basilar artery.

2003

As a previous step to consider their use in the pharmacology for stroke, we investigated the effects of four phytoestrogens (i.e. genistein, daidzein, zearalanone and biochanin A) on cerebral vessels. Cerebral vascular responses were analyzed by conventional recording of isometric tension in rabbit basilar artery segments kept in organ bath under standard conditions. The four phytoestrogens elicited concentration-dependent relaxant responses of different potency in basilar artery segments previously contracted with either 5x10(-2) M KCl or 10(-4) M UTP. Neither endothelium removal, 10(-4) M N(omega)-nitro-L-arginine methyl ester (L-NAME, nitric oxide (NO) synthase inhibitor), 10(-5) M1 H-[1…

Riesgo de pobreza infantil y exclusión social en dos regiones españolas: determinantes sociales y familiares

2021

espanolObjetivo Describir el riesgo de pobreza y exclusion social en ninos/as de 8-11 anos de Gipuzkoa y Valencia (Espana), mediante los indicadores AROPE (At Risk Of Poverty or Social Exclusion), y evaluar sus factores asociados en el Proyecto INMA (Infancia y Medio Ambiente). Metodo Familias de Gipuzkoa y Valencia (394 y 382, respectivamente) completaron un cuestionario en 2015-2016. Se estimaron la baja intensidad de trabajo (BIT), el riesgo de pobreza (RP) y la privacion material (PM). AROPE consistio en cumplir cualquiera de estos subindicadores. Se consideraron caracteristicas sociodemograficas, familiares y parentales. Se usaron diagramas de Venn, los test de Ji-cuadrado y Fisher en …

A lycopene β-cyclase/lycopene ε-cyclase/light-harvesting complex-fusion protein from the green algaOstreococcus lucimarinuscan be modified to produce…

2015

Summary Biosynthesis of asymmetric carotenoids such as α-carotene and lutein in plants and green algae involves the two enzymes lycopene β-cyclase (LCYB) and lycopene e-cyclase (LCYE). The two cyclases are closely related and probably resulted from an ancient gene duplication. While in most plants investigated so far the two cyclases are encoded by separate genes, prasinophyte algae of the order Mamiellales contain a single gene encoding a fusion protein comprised of LCYB, LCYE and a C-terminal light-harvesting complex (LHC) domain. Here we show that the lycopene cyclase fusion protein from Ostreococcus lucimarinus catalyzed the simultaneous formation of α-carotene and β-carotene when heter…

Data on phase and chemical compositions of black sands from “El Ostional” beach situated in Mompiche, Ecuador

2020

Abstract Data revealing the phase and chemical compositions of natural black sands from “El Ostional” beach, located in the northern Ecuadorian Pacific coast have been presented. The samples were collected from six points over the shore area of approximately 500 × 40 m2. The data on crystalline phases (iron titanium oxide, orthoclase feldspar and zircon) were determined by X-ray powder diffraction (XRPD), while semi-quantitative chemical analyses of major (Fe and Ti) and trace elements were obtained by X-ray fluorescence spectroscopy (XRF). The phase composition was verified by scanning electron microscopy (SEM), using backscattered electron (BSE) mode and energy dispersive spectroscopy (ED…

An ion channel-gated adenylyl cyclase

1992

Nature and origin of the hematite-bearing plains of Terra Meridiani based on analyses of orbital and Mars Exploration rover data sets

2006

The ~5 km of traverses and observations completed by the Opportunity rover from Endurance crater to the Fruitbasket outcrop show that the Meridiani plains consist of sulfate-rich sedimentary rocks that are largely covered by poorly-sorted basaltic aeolian sands and a lag of granule-sized hematitic concretions. Orbital reflectance spectra obtained by Mars Express OMEGA over this region are dominated by pyroxene, plagioclase feldspar, crystalline hematite (i.e., concretions), and nano-phase iron oxide dust signatures, consistent with Pancam and Mini-TES observations. Mossbauer Spectrometer observations indicate more olivine than observed with the other instruments, consistent with preferentia…

Phase equilibrium constraints on conditions of granulite-facies metamorphism at Scourie, NW Scotland

2011

Abstract: The metamorphic evolution of a metapyroxenite and metagabbro from Scourie, NW Scotland, is investigated using phase equilibria modelled in the NCFMASHTO (Na 2 O–CaO–FeO–MgO–Al 2 O 3 –SiO 2 –H 2 O–TiO 2 –O) system. The calculated stability fields for the observed assemblages in each rock overlap and imply conditions of 8.5–11.5 kbar and 875–975 °C for the peak of granulite-facies (Badcallian) metamorphism. The lack of any evidence for the former presence of garnet in the metapyroxenite suggests that the rocks cannot have reached pressures much in excess of those recorded at the metamorphic peak. The growth of coronas of plagioclase, orthopyroxene and magnetite replacing garnet in t…

Using calculated chemical potential relationships to account for replacement of kyanite by symplectite in high pressure granulites

2015

Calculated mineral equilibria are used to account for the formation of sapphirine-plagioclase, spinel-plagioclase and corundum-plagioclase symplectites replacing kyanite in quartz-plagioclase-garnet-kyanite granulite facies gneisses from the Southern Domain of the Athabasca granulite terrane, a segment of the Snowbird tectonic zone in northern Saskatchewan, Canada. Metamorphic conditions of >14 kbar and 800 °C are established for the high pressure, garnet-kyanite assemblage using constraints from P-T pseudosections and Zr-in-rutile thermometry. Replacement of kyanite by symplectites reflects the reaction of kyanite with the matrix following near-isothermal decompression to <10 kbar. The che…

Experimental and thermodynamic constraints on mineral equilibrium inpantelleritic magmas

2020

Abstract Crystallization experiments on two pantellerites from Pantelleria, Italy, provide new evidence for the relationships between mineral phases in pantelleritic rocks as well as the influence of temperature and redox conditions on mineral assemblages. Experiments were performed at 1 kbar with temperature ranging between 750–900°C, and fluid saturation conditions with XH2O (=H2O/H2O+CO2) between 0 and 1. Redox conditions were fixed at, or slightly below, the FMQ buffer. Results show that at temperature of 900 °C pantelleritic magmas are well above the liquidus regardless their water content; we also observed a decrease in liquidus temperature (800°C) with increasingly reducing condition…

Retrograde melt-residue interaction and the formation of near-anhydrous leucosomes in migmatites

2010

Considering physical segregation of melt from its residue, the chemical potentials of the components (oxides) are the same in both when segregation occurs. Then, as P–T conditions change, gradients in chemical potential are established between the melt-rich domains and residue permitting diffusional interaction to occur. In particular, on cooling, the chemical potential of H2O becomes higher in the melt segregation than in the residue, particularly when biotite becomes stable in the residue assemblage. Diffusion of water from the melt to the residue promotes crystallization of anhydrous products from the melt and hydrous products in the residue. This diffusive process, when coupled with mel…