Filter-induced bias in Lyα emitter surveys: a comparison between standard and tunable filters. gran telescopio Canarias preliminary results

Lyα emitter (LAE) surveys have successfully used the excess in a narrowband filter compared to a nearby broadband image to find candidates. However, the odd spectral energy distribution (SED) of LAEs combined with the instrumental profile has important effects on the properties of the candidate samples extracted from these surveys. We investigate the effect of the bandpass width and the transmission profile of the narrowband filters used for extracting LAE candidates at redshifts z sime 6.5 through Monte Carlo simulations, and we present pilot observations to test the performance of tunable filters to find LAEs and other emission-line candidates. We compare the samples obtained using a narrow ideal rectangular filter, the Subaru NB921 narrowband filter, and sweeping across a wavelength range using the ultra-narrow-band tunable filters of the instrument OSIRIS, installed at the 10.4 m Gran Telescopio Canarias. We use this instrument for extracting LAE candidates from a small set of real observations. Broadband data from the Subaru, Hubble Space Telescope, and Spitzer databases were used for fitting SEDs to calculate photometric redshifts and to identify interlopers. Narrowband surveys are very efficient in finding LAEs in large sky areas, but the samples obtained are not evenly distributed in redshift along the filter bandpass, and the number of LAEs with equivalent widths <60 Å can be underestimated. These biased results do not appear in samples obtained using ultra-narrow-band tunable filters. However, the field size of tunable filters is restricted because of the variation of the effective wavelength across the image. Thus, narrowband and ultra-narrow-band surveys are complementary strategies to investigate high-redshift LAEs.This research has been partially funded by the UNAMDGAPA-PAPIIT IN110013 Program. J.A.D. and M.A.D. are grateful for support from CONACyT grant CB-128556. J.A.D. is grateful for support from grant SAB2010-0011 awarded by the Spanish MIED through the “Programa Nacional de Movilidad de Recursos Humanos” included in the Plan Nacional de I-D+i 2008-2011. T.V. acknowledges support from CONACYT grant 165365 through the program “Estancias posdoctorales y sabáticas al extranjero para la consolidación de grupos de investigación.” This work has been partially funded by the Spanish Ministry of Science and Innovation (MICINN) under the Consolider-Ingenio 2010 Program grant CSD2006-00070: First Science with the GTC (http://www.iac.es/consolider-ingenio-gtc), AYA2011-29517-C03-01, and AYA2011-29517-C03-02. Observations presented in this paper were made with the Gran Telescopio Canarias (GTC), installed in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias, on the island of La Palma. The authors are thankful to the anonymous referee for the critical and constructive suggestion

Low thermal conductivity in La-filled cobalt antimonide skutterudites with an inhomogeneous filling factor prepared under high-pressure conditions

La-filled skutterudites LaxCo4Sb12 (x : 0.25 and 0.5) have been synthesized and sintered in one step under high-pressure conditions at 3.5 GPa in a piston-cylinder hydrostatic press. The structural properties of the reaction products were characterized by synchrotron X-ray powder diffraction, clearly showing an uneven filling factor of the skutterudite phases, confirmed by transmission electron microscopy. The non-homogeneous distribution of La filling atoms is adequate to produce a significant decrease in lattice thermal conductivity, mainly due to strain field scattering of high-energy phonons. Furthermore, the lanthanum filler primarily acts as an Einstein-like vibrational mode having a strong impact on the phonon scattering. Extra-low thermal conductivity values of 2.39 W/mK and 1.30 W/mK are measured for La0.25Co4Sb12 and La0.5Co4Sb12 nominal compositions at 780 K, respectively. Besides this, lanthanum atoms have contributed to increase the charge carrier concentration in the samples. In the case of La0.25Co4Sb12, there is an enhancement of the power factor and an improvement of the thermoelectric properties

Dietary avian proteins are comparable to soybean proteins on the atherosclerosis development and fatty liver disease in apoe-deficient mice

Background and aim: The type and amount of dietary protein has become a topic of re-newed interest in light of their involvement in metabolic diseases, atherosclerosis and thrombosis. However, little attention has been devoted to the effect of avian proteins despite their wide human consumption. The aim was to investigate the influence of chicken and turkey as sources of protein compared with that of soybean on atherosclerosis and fatty liver disease. Methods and results: To this purpose, male and female Apoe-deficient were fed purified Western diets differing in their protein sources for 12 weeks. After this period, blood, liver, aortic tree and heart base samples were taken for analyses of plasma lipids and atherosclerosis. Plasma triglycerides, non-esterified fatty acids, esterified cholesterol levels and radical oxygen species in lipoproteins changed depending on the diet and sex. Females consuming the turkey protein-containing diet showed decreased athero-sclerotic foci, as evidenced by the en face atherosclerosis analyses. The presence of macrophages and smooth muscle cells in plaques were not modified, and no changes were observed in hepatic lipid droplets in the studied groups either. Paraoxonase activity was higher in the group consuming turkey protein without sex differences, but only in females, it was significantly associated with aor-tic lesion areas. Conclusions: Compared to soybean protein, the consumption of avian proteins depending on sex resulted in similar or lower atherosclerosis development and comparable hepatic steatosis. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

Carcass bone content in wild rabbits hunted in Andalusia (Spain)

Para caracterizar el contenido de hueso de la canal del conejo de monte ( Oryctolagus cuniculus algirus ) procedente de la ca- za, se analizaron 53 canales encorambradas adquiridas en mercados de abastos de Sevilla (España) con un peso medio de 767,8 g. Las canales encorambradas se desollaron y prepararon para obtener las canales de referencia, que tuvieron un peso medio de 551,2 g, Se realizó el despiece tecnológico propuesto por la World Rabbit Science Association, que rindió un 14,3% de patas delanteras, un 38,0% de patas traseras, un 32,1% de pieza lomo y un 11,4% de caja torácica. El contenido de hueso fue del 16,3% en las patas delanteras, 13,4% en las patas traseras, 9,4% en la pieza lomo, 22,5% en la caja torácica y 13,0% en el conjunto de la canal de referencia. El contenido de hueso de la pata trasera fue un predictor fiable del contenido de hueso de la canal de referencia, pues se obtuvo una R 2 =0,737 (p<0,001). No se encontró dimorfismo sexual en el contenido de hue- so ni correlación entre el peso de la canal y el contenido de hueso de la canal del conejo de monte. En comparación con los valores publicados para razas y líneas de aptitud cárnica a la edad de sacrificio habitual en España, el contenido de hueso de la canal del conejo de monte es moderado.With the aim to characterise the carcass bone content of the wild rabbit (Oryctolagus cuniculus algirus) obtained from hunting, 53 specimens (unskinned, eviscerated rabbits) bought in markets of Seville (Spain) were analysed. The specimens weighed 767.8 g. T he reference carcass, obtained by flaying the specimens, weighed 551.2 g, and after carrying out the technological division accord ing the method proposed by the World Rabbit Science Association, 14.3% of fore leg, 38.0% of hind part, 32.1% of loin, and 11.4% of tho ra- cic cage were obtained. Bone percentage was 16.3% in the fore leg, 13.4% in the hind part, 9.4% in the loin, 22.5% in the thora cic ca- ge, and 13.0 in the reference carcass. Bone percentage of the hind leg gave a reliable prediction of the bone percentage of the carcass, because R 2 =0,737 (p<0,001) was achieved. No sexual dimorphism was found for the bone content, nor correlation between carcass weight and bone content of the carcass of the wild rabbit. When compared to figures published for meat breeds and lines at the usual age of slaughtering in Spain, the bone content of the wild rabbit carcass is moderat

Nanostructured State-of-the-Art Thermoelectric Materials Prepared by Straight-Forward Arc-Melting Method

Thermoelectric materials constitute an alternative to harvest sustainable energy from waste heat. Among the most commonly utilized thermoelectric materials, we can mention Bi2Te3 (hole and electron conductivity type), PbTe and recently reported SnSe intermetallic alloys. We review recent results showing that all of them can be readily prepared in nanostructured form by arc-melting synthesis, yielding mechanically robust pellets of highly oriented polycrystals. These materials have been characterized by neutron powder diffraction (NPD), scanning electron microscopy (SEM) and electronic and thermal transport measurements. Analysis of NPD patterns demonstrates near-perfect stoichiometry of above-mentioned alloys and fair amount of anharmonicity of chemical bonds. SEM analysis shows stacking of nanosized sheets, each of them presumably single-crystalline, with large surfaces parallel to layered slabs. This nanostructuration affects notably thermoelectric properties, involving many surface boundaries (interfaces), which are responsible for large phonon scattering factors, yielding low thermal conductivity. Additionally, we describe homemade apparatus developed for the simultaneous measurement of Seebeck coefficient and electric conductivity at elevated temperatures

The role of extracellular matrix on liver stem cell fate: A dynamic relationship in health and disease

The liver stem cell niche is a specialized and dynamic microenvironment with biomechanical and biochemical characteristics that regulate stem cell behavior. This is feasible due to the coordination of a complex network of secreted factors, small molecules, neural, blood inputs and extracellular matrix (ECM) components involved in the regulation of stem cell fate (self-renewal, survival, and differentiation into more mature phenotypes like hepatocytes and cholangiocytes). In this review, we describe and summarize all the major components that play essential roles in the liver stem cell niche, in particular, growth factor signaling and the biomechanical properties of the ECM

Enhanced stability in CH3NH3PbI3 hybrid perovskite from mechano-chemical synthesis: structural, microstructural and optoelectronic characterization

Among the hybrid organic–inorganic perovskites MAPbX3 (MA: methyl-ammonium CH3–NH3+, X = halogen), the triiodide specimen (MAPbI3) is still the material of choice for solar energy applications. Although it is able to absorb light above its 1.6 eV bandgap, its poor stability in humid air atmosphere has been a major drawback for its use in solar cells. However, we discovered that this perovskite can be prepared by ball milling in a straightforward way, yielding specimens with a superior stability. This fact allowed us to take atomic-resolution STEM images for the first time, with sufficient quality to unveil microscopic aspects of this material. We demonstrated full Iodine content, which might be related to the enhanced stability, in a more compact PbI6 framework with reduced unit-cell volume. A structural investigation from neutron powder diffraction (NPD) data of an undeuterated specimen was essential to determine the configuration of the organic MA unit in the 100–298 K temperature range. A phase transition is identified, from the tetragonal structure observed at RT (space group I4/mcm) to an orthorhombic (space group Pnma) phase where the methyl-ammonium organic units are fully localized. Our NPD data reveal that the MA changes are gradual and start before reaching the phase transition. Optoelectronic measurements yield a photocurrent peak at an illumination wavelength of 820 nm, which is redshifted by 30 nm with respect to previously reported measurements on MAPbI3 perovskites synthesized by crystallization from organic solvents.Fil: Lopez, Carlos Alberto. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Área Química General e Inorgánica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Abia, Carmen. Instituto de Ciencia de Materiales de Madrid; España. Institut Laue Langevin; FranciaFil: Rodrigues, Joao E.. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Serrano Sánchez, Federico. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Nemes, Norbert M.. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Martínez, José L.. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Fernandez Díaz, María T.. Institut Laue Langevin; FranciaFil: Biškup, Neven. Universidad Complutense de Madrid; EspañaFil: Alvarez Galván, Consuelo. Consejo Superior de Investigaciones Científicas; EspañaFil: Carrascoso, Felix. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Castellanos Gomez, Andres. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Alonso, José A.. Instituto de Ciencia de Materiales de Madrid; Españ