Los efectos térmicos del Complejo Plutónico de Santa Eulalia (sur de Portugal) en las rocas metaígneas y metasedimentarias encajantes

The Santa Eulália Plutonic Complex (SEPC) is a late-Variscan granitic body located in the northern part of the Ossa Morena Zone, a inner zone of the Variscan Iberian Massif. The SEPC host rocks are composed of meta-igneous and metasedimentary units, from Upper Proterozoic to Paleozoic ages, with a NW-SE structure, cross-cut by the SEPC. The SEPC host rocks, with low grade metamorphism show well preserved primary sedimentary or igneous mineralogical, textural and structural features. The thermal effect induced by the SEPC is restricted to the roof pendants. At N and NE of the SEPC, textures and paragenesis resulting from thermal metamorphism, are not related to the SEPC intrusion but to a previous magmatism, controlled by the NW-SE regional anisotropies. The restriction of the thermal effects to the pluton roof may be caused by a combination of several interrelated factors: higher volume of granitic mass, thermal effect by advection of fluids and longer period of prevalence of high thermal conditions. The geochemical study of SEPC host rocks shows the heterogeneous character and diversity of metasedimentary, igneous and meta-igneous rocks. The whole rock geochemical data indicate that all the metasedimentary lithologies derived from an upper continental crustal source and the igneous and meta-igneous rocks show no evidence of metasomatic effects by the SEPC emplacement.El Complejo Plutónico de Santa Eulalia (CPSE) es un cuerpo granítico tardi-Varisco situado en la parte norte de la Zona de Ossa Morena, en la zona interior del Macizo Ibérico Varisco. Las rocas encajantes del CPSE están compuestas por unidades meta-ígneas y metasedimentarias, de edades que van desde el Proterozoico Superior hasta el Paleozoico, con una estructura de dirección NW-SE, cortada por el CPSE. Las rocas encanjantes del CPSE, con metamorfismo de bajo grado conservan estructuras, mineralogía y textura primarias. El efecto térmicoinducido por el CPSE se limita a los roof pendants. Al N y NE del CPSE, las texturas y paragénesis resultantes del metamorfismo térmico, no están relacionadas con la intrusión del CPSE sino con un magmatismo anterior, controlado por anisotropías regionales NW- SE. La restricción de los efectos térmicos al techo del pluton puede ser causada por una combinación de varios factores interrelacionados: mayor volumen de masa granítica, un efecto térmico por la advección de fluidos y el período de prevalencia de altas condiciones térmicas. Los datos geoquímicos de las rocas encanjantes del CPSE muestran el carácter heterogéneo y la diversidad de rocas sedimentarias, metasedimentarias, ígneas y meta-ígneas. El análisis de los datos geoquímicos indica que todas las litologías sedimentarias y metasedimentarias han derivado de la corteza continental superior, mientras las rocas ígneas y meta-ígneas tienen una composición que no muestra evidencias de efectos metasomáticos por el emplazamiento del CPSE

The role of Bi2O3 on the thermal, structural and optical properties of tungsten-phosphate glasses

Glasses in the ternary system (70 – x)NaPO3-30WO3-xBi2O3, with x = 0–30 mol %, were prepared by the conventional melt-quenching technique. X-ray diffraction (XRD) measurements were performed to confirm the noncrystalline nature of the samples. The influence of the Bi2O3 on the thermal, structural, and optical properties was investigated. Differential scanning calorimetry analysis showed that the glass transition temperature, Tg, increases from 405 to 440 °C for 0 ≤ x ≤ 15 mol % and decreases to 417 °C for x = 30 mol %. The thermal stability against devitrification decreases from 156 to 67 °C with the increase of the Bi2O3 content. The structural modifications were studied by Raman scattering, showing a bismuth insertion into the phosphate chains by Bi–O–P linkage. Furthermore, up to 15 mol % of Bi2O3 formation of BiO6 clusters is observed, associated with Bi–O–Bi linkage, resulting in a progressive break of the linear phosphate chains that leads to orthophosphate Q0 units. The linear refractive index, n0, was measured using the prism-coupler technique at 532, 633, and 1550 nm, whereas the nonlinear (NL) refractive index, n2 was measured at 1064 nm using the Z-scan technique. Values of 1.58 ≤ n0 ≤ 1.88, n2 ≥ 10–15 cm2/W and NL absorption coefficient, α2 ≤ 0.01 cm/GW, were determined. The linear and NL refractive indices increase with the increase of the Bi2O3 concentration. The large values of n0 and n2, as well as the very small α2, indicate that these materials have large potential for all-optical switching applications in the near-infrared

Third-order nonlinearities and other properties of molybdenum lead-pyrophosphate glass

Glasses in the binary system (100-x)Pb2P2O7-xMoO3, with x = 10 – 80 mol %, were synthesized by conventional melt-quenching technique. Thermal analysis, linear optical absorption, refractive index measurements, Raman scattering and nonlinear (NL) optical experiments were performed to characterize the samples. The dependence of MoO3 content on thermal, structural and optical properties was investigated. Molybdenum oxide increases both the glass transitions temperature and thermal stability against devitrification up to 50 mol % due to formations of P-O-Mo linkages and the glass network connectivity increases. The nonlinear optical properties were studied at 1064 nm and 532 nm with pulses of ≈17 ps. The NL refractive index measured was +10-19 m2/W at both wavelengths for samples with different relative concentrations of the constituent compounds. At 1064 nm we determined that the two-photon absorption coefficient, , is smaller than the minimum that we can measure ( <0.01 cm/GW) while at 532 nm we measured  0.25 cm/GW. The nonlinear response of the samples is attributed to contributions from the lone electron pairs of Pb2+, MoO3 clusters, and to Mo5+ and Mo4+ ions

Self-consistent Coulomb effects and charge distribution of quantum dot arrays

This paper considers the self-consistent Coulomb interaction within arrays of self-assembled InAs quantum dots (QDs) which are embedded in a pn structure. Strong emphasis is being put on the statistical occupation of the electronic QD states which has to be solved self-consistently with the actual three-dimensional potential distribution. A model which is based on a Green's function formalism including screening effects is used to calculate the interaction of QD carriers within an array of QDs, where screening due to the inhomogeneous bulk charge distribution is taken into acount. We apply our model to simulate capacitance-voltage (CV) characteristics of a pn structure with embedded QDs. Different size distributions of QDs and ensembles of spatially perodic and randomly distributed arrays of QDs are investigated.Comment: submitted to pr

Antioxidant properties of different dietary supplements based on Agaricus blazei Murrill

In 2012, the market for nutraceuticals earned $90 billion worldwide and it is predicted to reach$33.6 billion in the next four years. Agaricus blazei Murrill mushroom is native to Brazil and widely cultivated due to nutritional and medicinal value [I ,2]. Its beneficial effects have long been recognized, becoming popular as ordinary food, increasing also its production and marketing as dietary supplements (3]. A. blazei is traditionally used to combat a variety of diseases such as cancer, diabetes, hepatitis and hypercholesterolemia [2]. The use of dietary supplements based on A. blazei has grown significantly, due to pharmacological studies reporting antioxidant, antitumor, anti-inflammatory, antimicrobial, immunostimulant, apoptotic and chemopreventive effects [2,3], attributed to ®-glucans and other bioactive compounds, such as steroids, tocopherols and phenolic compounds [4]. Herein, the antioxidant activity of A. blazei capsules enriched with fmits of Malpighia glabra L. (acerola), Solanum melongena L. (eggplant) and Euterpe oleracea Mart. (açai), calcium and chitosan, were evaluated though in vitro assays: DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, reducing power, inhibition of G-carotene bleaching and inhibition of lipid peroxidation in brain homogenates by thiobarbituric acid reactive substances (TSARS) assay. Two capsules (daily recommended dose) were dissolved in 100 mL of distilled water in order to prepare a stock solution. Several dilutions were tested until determination of EC50 values (concentration responsible for 50% of antioxidant activity or 0.5 of absorbance in reducing power assay). Globally, all the tested formulations showed high antioxidant activity. A. blazei with acerola gave the highest DPPH scavenging activity (EC50=0.81±0.0 1 mg/mL) and reducing power (EC50=0.53±0.0 1 mg/mL). Nevertheless, A. blazei with ayai showed the highest activity in the lipophilic assays: f3 - carotene bleaching inhibition (EC50=0.55±0.02 mg/mL) and lipid peroxidation inhibition by TSARS assay (EC50=O. 14±0.01 mg/mL). The studied formulations might be useful as antioxidants-enriched supplements to prevent some of the diseases related to oxidative stress

Association between ventilation index and time on mechanical ventilation in infants with acute viral bronchiolitis

OBJECTIVE: To evaluate the association between time on mechanical ventilation and anthropometric, clinical and pulmonary function variables, measured early, in infants on invasive mechanical ventilation with acute respiratory failure due to viral bronchiolitis, and the temporal progression of variables with significant correlations. METHODS: Twenty-nine infants admitted to the pediatric intensive care unit of UNICAMP university hospital were studied. Acute viral bronchiolitis was defined according to clinical and radiological criteria. Children with chronic diseases and those that were hemodynamically unstable were excluded. All measurements were taken after 24 to 72 hours' mechanical ventilation, using volumetric capnography and blood gas analysis. Mechanical ventilation time was divided into: 7 days. Association between time on mechanical ventilation and the variables analyzed was determined by Spearman's Correlation Coefficient (r s). RESULTS: Time on mechanical ventilation showed a significant positive correlation with PaCO2 (r s = 0.45, p = 0.01) and ventilation index (r s = 0.51, p = 0.005), and a negative correlation with pH (r s = -0.40, p = 0.03). Ventilation indices of 37, measured between day one and day five, was associated with a progressively increased risk of more than 7 days on mechanical ventilation (OR = 4.2 on the first day to 15.71 on the fourth day). CONCLUSION: Ventilation index, PaCO2 and pH, measured early, were associated with prolonged mechanical ventilation, reflecting the severity of ventilatory disturbance and the need for support.OBJETIVO: Avaliar a associação entre tempo de ventilação mecânica e variáveis antropométricas, clínicas e de função pulmonar, precocemente, em lactentes com insuficiência respiratória por bronquiolite viral aguda em ventilação mecânica invasiva, e a evolução temporal das variáveis significativamente correlacionadas. MÉTODOS: Foram estudados 29 lactentes admitidos na unidade de terapia intensiva pediátrica do Hospital de Clínicas da UNICAMP, com diagnóstico de bronquiolite viral aguda, definido por critérios clínicos e radiológicos. Lactentes com doenças crônicas ou instabilidade hemodinâmica foram excluídos. Todas as medidas foram feitas entre 24 e 72 horas em ventilação mecânica, usando capnografia volumétrica e análise dos gases sangüíneos. O tempo de ventilação mecânica foi dividido em: menor ou igual que 7 dias e maior que 7 dias. A associação entre o tempo de ventilação e as variáveis analisadas foi determinada pelo coeficiente de correlação de Spearman (r s) RESULTADOS: O tempo de ventilação mecânica apresentou correlação positiva significativa com a PaCO2 (r s = 0,45, p = 0,01) e com o índice de ventilação (r s = 0,51, p = 0,005), e negativa com o pH (r s = -0,40, p = 0,03). Índice de ventilação com valor de 37, avaliado do primeiro ao quinto dia, foi associado a risco progressivamente aumentado de tempo de ventilação mecânica maior que 7 dias (OR = 4,2 no primeiro dia a 15,71 no quarto dia) CONCLUSÕES: Índice ventilatório, PaCO2 e pH, precocemente medidos, foram associados com tempo prolongado em ventilação mecânica, refletindo a gravidade do distúrbio ventilatório e necessidade de suporte.46647