Resolving galaxies in time and space: II: Uncertainties in the spectral synthesis of datacubes

In a companion paper we have presented many products derived from the application of the spectral synthesis code STARLIGHT to datacubes from the CALIFA survey, including 2D maps of stellar population properties and 1D averages in the temporal and spatial dimensions. Here we evaluate the uncertainties in these products. Uncertainties due to noise and spectral shape calibration errors and to the synthesis method are investigated by means of a suite of simulations based on 1638 CALIFA spectra for NGC 2916, with perturbations amplitudes gauged in terms of the expected errors. A separate study was conducted to assess uncertainties related to the choice of evolutionary synthesis models. We compare results obtained with the Bruzual & Charlot models, a preliminary update of them, and a combination of spectra derived from the Granada and MILES models. About 100k CALIFA spectra are used in this comparison. Noise and shape-related errors at the level expected for CALIFA propagate to 0.10-0.15 dex uncertainties in stellar masses, mean ages and metallicities. Uncertainties in A_V increase from 0.06 mag in the case of random noise to 0.16 mag for shape errors. Higher order products such as SFHs are more uncertain, but still relatively stable. Due to the large number statistics of datacubes, spatial averaging reduces uncertainties while preserving information on the history and structure of stellar populations. Radial profiles of global properties, as well as SFHs averaged over different regions are much more stable than for individual spaxels. Uncertainties related to the choice of base models are larger than those associated with data and method. Differences in mean age, mass and metallicity are ~ 0.15 to 0.25 dex, and 0.1 mag in A_V. Spectral residuals are ~ 1% on average, but with systematic features of up to 4%. The origin of these features is discussed. (Abridged)Comment: A&A, accepte

Room-temperature Operation of Low-voltage, Non-volatile, Compound-semiconductor Memory Cells

Whilst the different forms of conventional (charge-based) memories are well suited to their individual roles in computers and other electronic devices, flaws in their properties mean that intensive research into alternative, or emerging, memories continues. In particular, the goal of simultaneously achieving the contradictory requirements of non-volatility and fast, low-voltage (low-energy) switching has proved challenging. Here, we report an oxide-free, floating-gate memory cell based on III-V semiconductor heterostructures with a junctionless channel and non-destructive read of the stored data. Non-volatile data retention of at least 104 s in combination with switching at ≤2.6 V is achieved by use of the extraordinary 2.1 eV conduction band offsets of InAs/AlSb and a triple-barrier resonant tunnelling structure. The combination of low-voltage operation and small capacitance implies intrinsic switching energy per unit area that is 100 and 1000 times smaller than dynamic random access memory and Flash respectively. The device may thus be considered as a new emerging memory with considerable potential

Pilot3 D1.1 - Technical resources and problem definition

This deliverable starts with the proposal of Pilot3 but incorporates the development produced during the first four months of the project: activities on different workpackages, interaction with Topic Manager and Project Officer, and input received during the first Advisory Board meeting. This deliverable presents the definition of Pilot3 concept and methodology. It includes the high level the requirements of the prototype, preliminary data requirements, preliminary indicators that will be considered and a preliminary definition of case studies. The deliverable aims at defining the view of the consortium on the project at these early stages, while highlighting the feedback obtained from the Advisory Board and the further activities required to define some of the aspects of the project

ACTIVIDAD ANTAGONICA DE HONGOS ENDOFITOS DE PLANTAS MEDICINALES DEL ECUADOR SOBRE BACTERIAS PATOGENAS

Mediante una investigación a lo largo del sector suburbano de la ciudad de Loja-Ecuador, dedicada al cultivo de plantas medicinales, se aíslaron los hongos endófitos asociados a Baccharis latifolia (Ruiz & Pav.)Pers., Baccharis obtusifolia Kunth, Piper barbatum Kunth, Borreria laevis (Lam.) Grises, Chuquiragua jussieui J.F. Gmel y Bidens andicola Kunth. Los taxa fúngicos más frecuentes fueron: Alternaria, Aspergillus, Epicoccum, Fusarium, Nigrospora, Phoma, además de algunos representantes de los grupos: coelomycetes, sinnematosos y Zygomycota. La mayor dominancia fúngica correspondió a integrantes de los denominados «Mycelia sterilia», siendo de particular interés comoposibles endófitos. Se evaluó además la interacción antagónica de siete aislados fúngicos frente a bacterias: Staphylococcus aureus, Klebsiella pneumomiae,  Pseudomonas aeruginosa y Escherichia coli. La mayoríade las cepas fúngicas estudiadas presentaron actividad, pero los resultados más prometedores se evidenciaron en un aislado de «Mycelia sterilia»

actividad antagonica de hongos endofitos de plantas medicinales del ecuador sobre bacterias patogenas

Mediante una investigacion a lo largo del sector suburbano de la ciudad de Loja-Ecuador, dedicada al cultivo de plantas medicinales, se aislaron los hongos endofitos asociados a Baccharis latifolia (Ruiz & Pav.) Pers., Baccharis obtusifolia Kunth, Piper barbatum Kunth, Borreria laevis (Lam.) Grises, Chuquiragua jussieui J.F. Gmel y Bidens andicola Kunth. Los taxa fungicos mas frecuentes fueron: Alternaria, Aspergillus, Epicoccum, Fusarium, Nigrospora, Phoma, ademas de algunos representantes de los grupos: coelomycetes, sinnematosos y Zygomycota. La mayor dominancia fungica correspondio a integrantes de los denominados «Mycelia sterilia», siendo de particular interes como posibles endofitos. Se evaluo ademas la interaccion antagonica de siete aislados fungicos frente a bacterias: Staphylococcus aureus, Klebsiella pneumomiae, Pseudomonas aeruginosa y Escherichia coli. La mayoria de las cepas fungicas estudiadas presentaron actividad, pero los resultados mas prometedores se evidenciaron en un aislado de «Mycelia sterilia»

Effect of sugar beet pulp fibre fractions on growth performance, fecal digestibility and digestive physiology in rabbits around weaning

The present study investigated the effect of the different fibre components of sugar beet pulp (SBP) on growth performance and some digestive traits. Four semi-synthetic diets were formulated with similar NDF (33% DM) and protein (16% DM) level. Control diet was formulated to contain the lowest level of soluble fibre (3% DM) and SBP diet the highest (9%). The soluble (pectins) and insoluble fractions of SBP were studied in other two diets (Pectin and InsSBP diets). A total of 136 weanling rabbits (25 d of age) was housed individually, randomly assigned to 4 experimental groups, and fed ad libitum with the experimental diets during 10 days after weaning. The type of diet did not affect growth rate and stomach pH. Animals fed with SBP diet showed higher DM and NDF digestibility (4 and 83%, respectively), gain:feed ratio (13%), cecal and total tract weight (13 and 9%) and ileal viscosity (148%) than rabbits fed the Control diet, but lower cecal pH (9%). Pectin diet increased ileal viscosity and decreased the weight of stomach content with respect to SBP diet. Rabbits fed InsSBP diet showed similar results to SBP diet but lower ileal viscosity and cecal pH than those fed Pectin diet. In conclusion, SBP and their soluble and insoluble fractions are well digested in young rabbits. However the soluble and insoluble fibre of SBP produce different effects in the gastrointestinal tract

Star formation histories in mergers: the spatially resolved properties of the early-stage merger luminous infrared galaxies IC 1623 and NGC 6090

The role of major mergers in galaxy evolution is investigated through a detailed characterization of the stellar populations, ionized gas properties and star formation rates (SFR) in the early-stage merger luminous infrared galaxies (LIRGs) IC 1623 W and NGC 6090, by analysing optical integral field spectroscopy and high-resolution Hubble Space Telescope imaging. The spectra were processed with the starlight full spectral fitting code, and the emission lines measured in the residual spectra. The results are compared with non-interacting control spiral galaxies from the Calar Alto Legacy Integral Field Area survey. Merger-induced star formation is extended and recent, as revealed by the young ages (50–80 Myr) and high contributions to light of young stellar populations (50–90 per cent), in agreement with merger simulations in the literature. These early-stage mergers have positive central gradients of the stellar metallicity, with an average ∼0.6 Z⊙. Compared to non-interacting spirals, they have lower central nebular metallicity, and flatter profiles, in agreement with the gas inflow scenario. We find that they are dominated by star formation, although shock excitation cannot be discarded in some regions, where high velocity dispersion is found (170–200 km s−1). The average SFR in these early-stage mergers (∼23–32 M⊙ yr−1) is enhanced with respect to main-sequence Sbc galaxies by factors of 6–9, slightly above the predictions from classical merger simulations, but still possible in about 15 per cent of major galaxy mergers, where U/LIRGs belong

STERapp: semiautomatic software for stereological analysis. Application in the estimation of fish fecundity

Postprin