62 research outputs found
Diseño e implementación de una arquitectura software OSGi para gestionar repositorios remotos de componentes
Cava Montesinos, S. (2011). Diseño e implementación de una arquitectura software OSGi para gestionar repositorios remotos de componentes. http://hdl.handle.net/10251/11117.Archivo delegad
Surface Equilibrium Angle for Anisotropic Grain Growth and Densification Model in Ceramic Materials
Photoresponse of KNbO3–AFeO3 (A = Bi3+ or La3+) ceramics and its relationship with bandgap narrowing
The crystal structure of (1-x)KNbO3–xBiFeO3 (KNBF) and (1-x)KNbO3-LaFeO3 (KNLF) (where x=0.00; 0.01; 0.02; 0.04; 0.08; 0.16; 0.32) was evaluated by XRD and Raman spectroscopy. XRD data show the crystal symmetry to evolve from orthorhombic to tetragonal with increasing x. The optical bandgap was found to narrow systematically with increasing x. Raman spectroscopy analysis corroborated long-range polar order in all compositions. The photoresponse of x=0.32 shows a typical diode–like behaviour, with current and voltage of 0.115 µA and 0.075 V for KNBF and 0.19 µA and 0.035 V for KNLF, respectively. To our knowledge these represent the largest values among KNbO3–based ceramics, making them promising for photovoltaic applications
Height cohorts and district of residence in the city of Madrid during the 20th century
OBJECTIVE: in recent decades, an interesting literature has accumulated regarding the biological living standard in Spain at the end of the 19th Century and during the 20th Century. Adult height has been one of the most studied variables, specifically its temporal change at the national and provincial levels, the impact of the Civil War and the subsequent dictatorship, and the differences between urban and rural areas. We want to contribute to this general overview with the presentation of a project about an intra-urban perspective of the city of Madrid. METHODS: We present the stature data of the male population of two Madrid districts, Salamanca and Vallecas, for the period 1936-1986 (year of measurement). RESULTS: In these years, height increased by 5.58 cm, from 166.40 to 171.98 cm, with significant differences observed between both districts as well as a simultaneous decrease of that difference, for those born in 1915 and 1953 from 3.09 to 1.2 cm. The negative effect of the Civil War and the years of autarky are also observed in this urban sample. CONCLUSION: Considering these data together with those available for other demographic and socioeconomic variables, before and after the period studied, we can conclude that the division by districts represents an effective stratification in the biological living standard of the population of the city of Madrid. These results constitute a first intra-urban approximation using height to the debate on inequality and biological living standards in Spain during the 20th Century.Objetivo: en las últimas décadas se ha acumulado una interesante bibliografía sobre los niveles biológicos de vida en España a finales del siglo
xix y durante el siglo xx. La talla ha sido una de las variables más estudiadas: su cambio a nivel nacional y provincial, el impacto de la Guerra Civil
y de la posterior dictadura y las diferencias entre las áreas urbanas y las rurales. Queremos contribuir a este panorama general con este trabajo,
una perspectiva intraurbana de la ciudad de Madrid.
Métodos: presentamos el análisis comparativo del cambio temporal en la talla de los madrileños de los distritos de Salamanca y de Vallecas
correspondientes al periodo 1936-1986.
Resultados: en esos años, la talla total se incrementó en 5,58 cm, pasando de 166,40 a 171,98 cm, aunque se observan diferencias significativas
entre ambos distritos; diferencias que se reducen (de 3,09 a 1,2 cm) entre Salamanca y Vallecas para los nacidos en 1915 y 1953,
respectivamente. También se observa el efecto negativo de la Guerra Civil y de los años de autarquía.
Conclusión: considerando estos primeros datos, junto a los disponibles para otras variables demográficas y socioeconómicas previas y posteriores
al periodo estudiado, podemos considerar que la división por distritos representa una estratificación efectiva en los niveles biológicos de vida
dentro de la ciudad de Madrid. Estos resultados constituyen una primera aproximación intraurbana con la talla al debate sobre la desigualdad y los niveles de vida en España durante el siglo xxLa publicación de este trabajo ha sido sufragada con fondos del proyecto HAR2016-
76814-C2-2-P del Ministerio de Economía, Industria y Competitividad (MINECO-FEDER-UE
SonoVue renal wash-in/wash-out curve analysis detects cortical perfusion defects in patients with significant renal artery stenosis and renin activation
Mixed electrical conduction of calcium aluminates synthesized by polymeric precursors
A study of the electrical transport properties of calcium aluminate (CA) with coexisting C3A and C12A7 phases was carried out. In this work, powders resulting from synthesis based on the polymer precursor method. The resulting product was characterized by means of XRD, Raman, and UV-visible analysis to obtain the optical BG and by EIS. From the XRD and Raman analyses, the presence and coexistence of the two self-modified phases were confirmed. In this biphasic composition, celite phase was estimated to be the major phase. An optical BG of 5.69 eV at room temperature was calculated, and under the condition of a reducing atmosphere in the temperature range of 750-950 ºC, an activation energy for conduction of 2.98 eV was determined by EIS measurements. Further, in this biphasic sample, the electronic conduction transport might be governed by the mayenite minor phase due to its large defect nature and concentration compared to celite. In oxidizing conditions, the activation energy for electrical conduction was 1.42 eV, which is somewhat higher than that observed by other authors in mayenite single phase; this result was explained by taking into account the coexistence of biphasic material and an actual chemical defect scenario in SMCM is discussed
Thromboxane inhibition improves renal perfusion and excretory function in severe congestive heart failure
AbstractObjectivesThe aim of this study was to evaluate whether thromboxane inhibition can favorably affect renal perfusion and clinical conditions in patients affected by severe heart failure.BackgroundThe renal formation of the vasoconstrictor thromboxane A2(TxA2) is increased during cardiac failure.MethodsBy oral administration of picotamide (a renal TxA2synthase and TxA2/prostaglandin H2receptor inhibitor), we blocked renal TxA2. Fourteen patients in New York Heart Association functional class IV were studied according to a randomized, double-blinded, cross-over design. Each of the two eight-day periods of testing was preceded by a three-day period during which certain vasoactive medications were stopped.ResultsDaily 24-h total urinary thromboxane B2(TxB2), the stable metabolite of TxA2, dropped at the end of picotamide treatment (p < 0.01 vs. baseline). Compared with placebo, effective renal plasma flow and the glomerular filtration rate increased (p < 0.01 and p < 0.05, respectively), thus leading to a significant decrease in the filtration fraction (p < 0.01). Renal vascular resistance decreased consistently (p < 0.01). In all patients, picotamide treatment was associated with an increase in diuresis and natriuresis (p < 0.001 vs. baseline). Plasma creatinine decreased (p < 0.05 vs. baseline). Patients also showed improvement in several clinical parameters, including a significant decrease in both pulmonary and venous pressure (p < 0.01 vs. baseline).ConclusionsThese results indicate that renal thromboxane formation plays an important role in renal vascular resistance in patients with severe heart failure, such as those described in the present study. Inhibition of TxA2improves renal hemodynamics and kidney function and favorably affects indexes of cardiac performance
Fingerprints of Short-Range and Long-Range Structure in BaZr1−xHfxO3 Solid Solutions: An Experimental and Theoretical Study
A microwave-assisted hydrothermal method was applied to synthesize BaZr1xHfxO3, (BZHO) solid
solutions at a low temperature, 140 1C, and relatively short times, 160 min. The detailed features of the
crystal structure, at both short and long ranges, as well as the crystal chemistry doping process, are
extensively analysed. X-ray diffraction measurements and Raman spectroscopy have been used to
confirm that pure and Hf-doped BZO materials present a cubic structure. Extended X-ray absorption
fine structure (EXAFS) spectra indicate that Hf4+ ions have replaced the Zr4+ ions on the 6-fold
coordination and a subsequent change on the Ba2+ 12-fold coordination can be sensed. X-ray
absorption near-edge structure (XANES) spectroscopy measurements reveal a local symmetry breaking
process, associated to overlap of the 4d–2p and 5d–2p orbitals of Zr–O and Hf–O bonds, respectively.
Field emission scanning electron microscopy (FE-SEM) and high resolution transmission electron
microscopy (HRTEM) show the mesocrystalline nature of self-assembled BZHO nanoparticles under a
dodecahedron shape. In addition first principle calculations were performed to complement the
experimental data. The analysis of the band structures and density of states of the undoped BZO and
doped BZHO host lattice allow deep insight into the main electronic features. The theoretical results
help us to find a correlation between simulated and experimental Raman modes and allow a more
substantial interpretation of crystal structure.Brazilian research funding institution FAPESP. 2009/17752-0
FAPERGS. 2031-2551/13-9SIAS
CNPq (MCT/CNPq). 458452/2014-9
Generalitat Valenciana. Prometeo/2009/053
Ministerio de Ciencia e Innovacion. CTQ-2012-36253-C03-01
Programa de Cooperacion Cientificacon Iberoamerica (Brazil), Ministerio de Educacion. PHB2009-0065-P
Microwave-assisted solvothermal : an efficient and new method to obtain hydrophobic wood surfaces
The objective of this work was to form a hydrophobic surface in a highly porous wood by coating and incorporating TiO2 micro/nano structures through the microwave-assisted solvotermal method, without need any pre- or post-modification of the wood substrate, using low temperatures and short times. The behavior and morphology of the TiO2-treated surfaces was characterized using scanning electron microscopy (SEM), while the elemental composition was determined via energy-dispersive X-ray spectroscopy and X-ray diffraction analysis. The results indicated that the crystallization of the TiO2 anatase phase was efficient and fully coated the wood surface during the solvothermal process. The treated wood contained TiO2 particles agglomerate with an average diameter of 200 nm that also allowed to coat an abundant fraction of tracheids cell walls. When investigated through X-ray spectroscopy-mapping, the element titanium appeared abundantly throughout the wood. After TiO2 growth in wood through the microwave-assisted solvotermal method, a roughness at the micro/ nano scales structures was created on the wood surface, originating an increase in the contact angle up to 137°, which characterizes the appearance of a hydrophobic surface. The TiO2-treated wood demonstrated 85% of water absorption after 400 h of immersion, while untreated wood reached 160%, suggesting that the microwave-assisted solvotermal process promotes a delay in the progression of water absorption. This feature can improve the dimensional stability of wood, contributing to the increase of its durability and applications
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