Two Superconducting Phases in CeRh_1-xIr_xIn_5

Pressure studies of CeRh_1-xIr_xIn_5 indicate two superconducting phases as a function of x, one with T_c >= 2 K for x < 0.9 and the other with T_c < 1.2 K for x > 0.9. The higher T_c phase, phase-1, emerges in proximity to an antiferromagnetic quantum-critical point; whereas, Cooper pairing in the lower T_c phase-2 is inferred to arise from fluctuations of a yet to be found magnetic state. The T-x-P phase diagram of CeRh_1-xIr_xIn_5, though qualitatively similar, is distinctly different from that of CeCu_2(Si_1-xGe_x)_2.Comment: 5 pages, 3 figure

Spatial scaling of species abundance distributions

Copyright © 2012 The Authors. Ecography © 2012 Nordic Society Oikos.Species abundance distributions are an essential tool in describing the biodiversity of ecological communities. We now know that their shape changes as a function of the size of area sampled. Here we analyze the scaling properties of species abundance distributions by using the moments of the logarithmically transformed number of individuals. We find that the moments as a function of area size are well fitted by power laws and we use this pattern to estimate the species abundance distribution for areas larger than those sampled. To reconstruct the species abundance distribution from its moments, we use discrete Tchebichef polynomials. We exemplify the method with data on tree and shrub species from a 50 ha plot of tropical rain forest on Barro Colorado Island, Panama. We test the method within the 50 ha plot, and then we extrapolate the species abundance distribution for areas up to 5 km2. Our results project that for areas above 50 ha the species abundance distributions have a bimodal shape with a local maximum occurring for the singleton classes and that this maximum increases with sampled area size

Electronic structure, optical and magnetic properties of Co2_{2}FeGe Heusler alloy films

Optical properties of ferromagnetic half-metallic full-Heusler Co$_{2}$FeGe alloy are investigated experimentally and theoretically. Co$_{2}$FeGe thin films were obtained by DC magnetron sputtering and show the saturation magnetization at $T$=10 K of $m\approx$5.6 $\mu_{B}$/f.u., close to the value predicted by the Slater-Pauling rule. First-principles calculations of the electronic structure and the dielectric tensor are performed using the full-potential linearized-augmented-plane-wave method in the generalized gradient (GGA) and GGA+U approximations. The measured interband optical conductivity spectrum for the alloy exhibits a strong absorption band in the 1 - 4 eV energy range with pronounced fine structure, which agrees well with the calculated half-metallic spectrum of the system, suggesting a near perfect spin-polarization in the material.Comment: 6 pages, 9 figure

Compostos fenólicos em frutos de bananeira.

Os compostos fenólicos são encontrados em muitas frutas e a quantificação desses metabólicos revela informações importantes a respeito da qualidade dos alimentos e dos potenciais benefícios à saúde (atividade antioxidante e atitumoral, e.g. - TALCOTT et al., 2003). A banana é amplamente consumida por todas as classes sociais e seu consumo é elevado, alcançando 162 Kg/pessoa/ano em algumas regiões da África (FAO, 2012)

Influência da época do ano e das diferentes formas de aplicação de ácido naftaleno acético (ANA) no enraizamento de Mikania micrantha Kunth.

Mikania micrantha Kunth é uma espécie nativa do Brasil, heliófila e de hábito rasteiro. É amplamente difundida na medicina popular e potencialmente utilizada na recuperação de áreas degradadas. O objetivo deste trabalho foi verificar a influência de diferentes formulações e vias de aplicação de ácido naftaleno acético (NAA) no enraizamento de estacas caulinares de Mikania micrantha Kunth coletadas nas quatro estações do ano. Estacas herbáceas provenientes de plantas matrizes nativas da região de Colombo - Paraná foram coletadas na primavera/2002, verão/2003, outono/2003 e inverno/2003, confeccionadas com 10 cm de comprimento e uma folha cortada pela metade mantida no ápice, desinfestadas e submetidas aos seguintes tratamentos (T): T, (Omg Kg-lANA), T2 (5000 mg Kg-l ANA), T3 (5000 mg Kg-1ANA- RAIZON 05@),T4 (5000 mg L-I ANA), T, (O mg L-' ANA) e Te (água). O plantio foi realizado em tubetes de polipropileno (55 crn-) contendo vermiculita de granulometria média, sendo as estacas mantidas em casa-devegetação com nebulização intermitente. Após 20 dias foram avaliadas as seguintes características: porcentagem de estacas enraizadas, número e comprimento das três maiores raízes por estaca, porcentagem de estacas vivas (sem raiz e sem calos) e porcentagem de estacas mortas. A análise estatística constou de um delineamento inteiramente casualizado (DIC) composto por seis tratamentos com quatro repetições de 24 estacas por parcela. A espécie foi considerada de fácil enraizamento, apresentando as maiores porcentagens na primavera, verão e outono (superiores a 86%), dispensando o uso de regulador vegetal para a indução radicial

Chemical, structural and proteomic profile of buffalo milk powder produced in mini spray dryer.

Abstract: The objective of this work was to obtain buffalo milk powder through the process of drying in mini spray dryer, and evaluate its physical, chemical, structural and proteomic features during storage. The buffalo milk was subjected to drying by atomization, air temperature of 140°C inlet. The samples were evaluated at times 0, 30, 60, 90, 120 and 150 days of storage. The moisture content, fat, protein, ash, density, acidity, solubility index, burning particles were analysed, along with structural analysis by Scanning Electron Microscopy (SEM) and proteomic study (SDS-PAGE). The production of milk powder from the set standards produced a buffalo milk powder with satisfactory results of physical and chemical compositions. In the SEM analysis was possible to observe an accumulation of milk powder particles with withered and wrinkled structures. Variations in the intensity of the bands of protein fractions were observed by electrophoresis, but no significant changes. The production secured buffalo milk powder with good quality characteristics, without any undesirable changes in the product during the storage time. [Perfil quimico, estructural y proteomico de leche en polvo del bufalo producido en mini secador por aspersion]. Resumen: El objetivo de este estudio fue obtener leche de bufala en polvo por el proceso de secado en un mini secador por aspersion y evaluar sus caracter?sticas f?sicas, qu?micas, estructurales y proteomicas durante el almacenamiento. La leche de bufala se sometio a secado por atomizacion, con la temperatura del aire de entrada de 140°C. Las muestras se evaluaron en los tiempos 0, 30, 60, 90, 120 y 150 d?as de almacenamiento. El contenido de humedad, grasa, prote?na, cenizas, densidad, acidez, ?ndice de solubilidad, part?culas quemadas se analizaron, junto con el analisis estructural mediante Microscop?a Electronica de Barrido (MEB) y el estudio prote ´ omico (SDS-PAGE). La produccion de leche de bufala en polvo cumpliendo con los estandares establecidos aseguro una composicion fisica y qu?mica satisfactoria. En el analisis de MEB fue posible observar una acumulacion de part?culas de leche en polvo con estructuras secas y arrugadas. Las variaciones en la intensidad de las bandas de las fracciones de prote?na fueron observadas por electroforesis, pero sin cambios significativos. La produccion de leche de b ´ ufala en polvo asegurado de las caracter?sticas de buena calidad, sin que ocurrieran cambios indeseados en el producto durante el tiempo de almacenamiento.[ANTONIO SILVIO DO EGITO VASCONCELOS]

Oxidative stability of functional phytosterol-enriched dark chocolate

A dark chocolate containing phytosterols (PS) esters was developed to reduce cholesterol in individuals. However, oxidative instability during chocolate processing and storage could reduce the PS bioactivity. Chocolate bars were prepared containing palm oil (CONT) or 2.2 g of PS (PHYT). All samples were stored at 20°C and 30°C during 5 months. A peak of hydroperoxides formation was observed after 60 days at 20°C and after 30 days at 30°C. PS-enriched samples presented higher values of hydroperoxides than control samples, which could be attributed to the higher level of alpha-linolenic acid present in the PHYT samples. All chocolate bars became lighter and softer after 90 days of storage. However, these physical changes did not reduce their sensory acceptability. In addition, PS bioactivity was kept during the storage, since no significant alterations in the PS esters were observed up to 5 months. However, some PS oxidation occurred in the PHYT bars, being sitostanetriol, 6-ketositosterol, 6beta-hydroxycampesterol and 7-ketocampesterol the major phytosterol oxidation products (POPs). The POPs/PS ratio was low (0.001). Therefore, the dark chocolate bars developed in this study kept their potential functionality after 5 months of storage at room temperature, representing an option as a functional food