Complete Analysis of Baryon Magnetic Moments in 1/N_c

We generate a complete basis of magnetic moment operators for the N_c = 3 ground-state baryons in the 1/N_c expansion, and compute and tabulate all associated matrix elements. We then compare to previous results derived in the literature and predict additional relations among baryon magnetic moments holding to subleading order in 1/N_c and flavor SU(3) breaking. Finally, we predict all unknown diagonal and transition magnetic moments to <= 0.15 mu_N accuracy, and suggest possible experimental measurements to improve the analysis even further.Comment: 28 pages (including 11 tables), ReVTeX. One reference and grant acknowledgment adde

Highly effective SERS nanopattern substrate. The enhancement is demonstrated using thiophenol as a molecular probe

The number of different types of Surface-enhanced Raman Scattering (SERS) substrates available for experimentation is increasing at high speed. New alternatives are introduced and explored every year in the literature including both novel nano-particles in solution as well as self-assembled or engineered structures with different levels of control over their optical properties. In this work silver nanopattern obtained by the nano-sphere lithography approach was prepared and characterized by AFM. This method basically exploits the regular patterns formed by self-assembly of dielectric (polystyrene, PS) nano-spheres on a surface upon drying. The evaporation of a silver film on top of the array can be followed by the lift-off of the nano-spheres themselves in which case an array of interstitial sites is left on the surface [1-2] (Fig. 1). We have observed in the AFM images that the shape of the nanopatterns is regular but the surface is rough and they are homogeneously distributed with dimensions in the sub-wavelength range.SERS properties of this substrate were examined by using thiophenol (TP) as molecular probe through the preparation of self-assembled monolayer (SAM) by dipping the substrates for 1h in 0.1mM solution of TP in CH2Cl2 at the temperature of 25ºC. Samples were subsequently rinsed with solutions solvents and dried before scanning. The surface interaction of this molecule has been studied by several groups and the most significant Raman change after the adsorption is the disappearance of the S-H stretching mode at about 2566 cm-1 in the SERS spectrum and indicating that an Ag-S bond has been formed [3]. The reproducibility on different areas of this substrate has been analyzed by using this molecular probe concluding that a fairly homogeneous distribution of the SERS intensity is observed (Fig. 2) which is a prerequisite for applications as ultrasensitive sensing assemblies.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Comparison between the thermal properties of cement composites using infrared thermal images

The use of agribusiness residual lignocellulosic fibres can be a good alternative in the development of lignocellulosic composites. The current work aimed to investigate the thermal performance of cement-based composites with lignocellulosic materials: Eucalyptus, sugarcane bagasse, coconut fibre in comparison with commercial gypsum board to be used as internal partitions of the building using infrared thermal images. Three repetitions for each kind of lignocellulosic material were made, and three commercial gypsum boards were used. In the production of the panels, the following parameters were applied: material and cement ratio, 1:2.75; water and cement ratio, 1:2.5; hydration water rate of 0.25; additive, 4% (based on cement mass). The calculations were performed for a nominal panel density of 1,200 kg m- ³. The thermal analysis was performed in a chamber composed of MDP (Medium-Density Particleboard) and with an internal layer of rock wool and the heat source (thermal resistance). For the superficial temperature measurement, a FLIR E75 camera was used to capture the infrared images. When the internal temperature of the chamber stabilized at 50 °C, an infrared thermal image was collected from each side of the composite. Thermal properties were analysed: thermal conductivity, resistivity, resistance, and transmittance. Based on the results, sugar cane cement composites were characterized by higher values of thermal conductivity. Related to thermal resistivity, thermal resistance, and thermal transmittance, only the coconut panel presented similar behaviour to the commercial gypsum board. Thus, cement composite using coconut can be a potential alternative that might solve energy and environmental concerns simultaneously

Effects of the 4N(v) chromosome from Aegilops ventricosa on agronomic and quality traits in bread wheat

Advanced wheat lines carrying the Hessian fly resistance gene H27 were obtained by backcrossing the wheat/Aegilops ventricosa introgression line, H-93-33, to commercial wheat cultivars as recurrent parents. The Acph-N v 1 marker linked to the gene H27 on the 4Nv chromosome of this line was used for marker assisted selection. Advanced lines were evaluated for Hessian fly resistance in field and growth chamber tests, and for other agronomic traits during several crop seasons at different localities of Spain. The hessian fly resistance levels of lines carrying the 4Nv chromosome introgression (4D/4Nv substitution and recombination lines that previously were classified by in situ hybridisation) were high, but always lower than that of their Ae. ventricosa progenitor. Introgression lines had higher grain yields in infested field trials than those without the 4Nv chromosome and their susceptible parents, but lower grain yields under high yield potential conditions. The 4Nv introgression was also associated with later heading, and lower tiller and grain numbers/m2 . In addition, it was associated with longer and more lax spikes, and higher values of grain weight and grain protein content. However, the glutenin and gliadin expression, as well as the bread-making performance, were similar to those of their recurrent parent

Distribution of hepatitis C virus genotypes among blood donors from mid-west region of Brazil

In order to investigate the hepatitis C virus (HCV) genotypes in mid-west region of Brazil, 250 anti-HCV positive blood donors were studied. Among them, the anti-HCV serological status was confirmed in 205 (82%). HCV RNA was detected in 165 samples, which were genotyped. HCV types 1, 2 and 3 were found in 67.9%, 3% and 29.1% of the donors, respectively. In Goiás state, subtype 1a (50%) was the most prevalent, followed by subtypes 3a (30.9%) and 1b (16.7%). In Mato Grosso state, subtype 1a was also predominant (41%), followed by subtypes 1b (29.5%) and 3a (25%). In Mato Grosso do Sul state, subtypes 1a and 1b were detected equally (36.8%), followed by 3a (21.1%). Subtype 2b was rare (2.4%, 4.5% and 5.3%, respectively). In Distrito Federal, subtype 3a (39%) was more frequent than 1a (31.7%) and the remaining (29.3%) belonged to subtype 1b.Com objetivo de determinar os genótipos do vírus da hepatite C (HCV) circulantes na Região Centro-Oeste do Brasil, 250 doadores de sangue anti-HCV positivos foram estudados. Dentre eles, a positividade para anti-HCV foi confirmada em 205 (82%). O RNA-HCV foi detectado em 165 amostras, as quais foram genotipadas. Os tipos 1, 2 e 3 do HCV foram encontrados em 67,9%, 3% e 29,1% dos doadores, respectivamente. No Estado de Goiás, o subtipo 1a (50%) foi o mais prevalente, seguido pelos subtipos 3a (30,9%) e 1b (16,7%). No Estado de Mato Grosso, o subtipo 1a (41%) foi também predominante, seguido pelos subtipos 1b (29,5%) e 3a (25%). No Estado de Mato Grosso do Sul, os subtipos 1a e 1b foram igualmente detectados (36,8%), seguidos por 3a (21,1%). O subtipo 2b foi raro (2,4%, 4,5% e 5,3%, respectivamente). No Distrito Federal, o subtipo 3a (39%) foi mais freqüente que 1a (31,7%), sendo o restante (29,3%) identificado como subtipo 1b

Two-bands superconductivity with intra- and interband pairing for synthetic superlattices

We consider a model for superconductivity in a two-band superconductor, having an anisotropic electronic structure made of two partially overlapping bands with a first hole-like and a second electron-like fermi surface. In this pairing scenario, driven by the interplay between interband $V_{i,j}$ and intraband $V_{i,i}$ pairing terms, we have solved the two gap equations at the critical temperature $T = T_c$ and calculate $T_c$ and the chemical potential $\mu$ as a function of the number of carriers $n$ for various values of pairing interactions, $V_{1,1}$, $V_{2,2}$, and $V_{1,2}$. The results show the complexity of the physics of condensates with multiple order parameters with the chemical potential near band edges.Comment: 6 pages, 2 figure

Relativistic Hydrodynamic Evolutions with Black Hole Excision

We present a numerical code designed to study astrophysical phenomena involving dynamical spacetimes containing black holes in the presence of relativistic hydrodynamic matter. We present evolutions of the collapse of a fluid star from the onset of collapse to the settling of the resulting black hole to a final stationary state. In order to evolve stably after the black hole forms, we excise a region inside the hole before a singularity is encountered. This excision region is introduced after the appearance of an apparent horizon, but while a significant amount of matter remains outside the hole. We test our code by evolving accurately a vacuum Schwarzschild black hole, a relativistic Bondi accretion flow onto a black hole, Oppenheimer-Snyder dust collapse, and the collapse of nonrotating and rotating stars. These systems are tracked reliably for hundreds of M following excision, where M is the mass of the black hole. We perform these tests both in axisymmetry and in full 3+1 dimensions. We then apply our code to study the effect of the stellar spin parameter J/M^2 on the final outcome of gravitational collapse of rapidly rotating n = 1 polytropes. We find that a black hole forms only if J/M^2<1, in agreement with previous simulations. When J/M^2>1, the collapsing star forms a torus which fragments into nonaxisymmetric clumps, capable of generating appreciable ``splash'' gravitational radiation.Comment: 17 pages, 14 figures, submitted to PR