More productive in vitro culture of Cryptosporidium parvum for better study of the intra- and extracellular phases

The great difficulties in treating people and animals suffering from cryptosporidiosis have prompted the development of in vitro experimental models. Due to the models of in vitro culture, new extracellular stages of Cryptosporidium have been demonstrated. The development of these extracellular phases depends on the technique of in vitro culture and on the species and genotype of Cryptosporidium used. Here, we undertake the molecular characterization by polymerase chain reaction-restriction fragment lenght polymorphism of different Cryptosporidium isolates from calves, concluding that all are C. parvum of cattle genotype, although differing in the nucleotide at positions 472 and 498. Using these parasites, modified the in vitro culture technique for HCT-8 cells achieving greater multiplication of parasites. The HCT-8 cell cultures, for which the culture had not been renewed in seven days, were infected with C. parvum sporozoites in RPMI-1640 medium with 10% IFBS, CaCl2 and MgCl2 1 mM at pH 7.2. Percentages of cell parasitism were increased with respect to control cultures (71% at 48 h vs 14.5%), even after two weeks (47% vs 1.9%). Also, the percentage of extracellular stages augmented (25.3% vs 1.1% at 96 h). This new model of in vitro culture of C. parvum will enable easier study of the developmental phases of C. parvum in performing new chemotherapeutic assays

Leishmanicidal Activity of Nine Novel Flavonoids from Delphinium staphisagria

Objectives. To evaluate the in vitro leishmanicidal activity of nine flavonoid derivatives from Delphinium staphisagria against L. infantum and L. braziliensis. Design and Methods. The in vitro activity of compounds 1–9 was assayed on extracellular promastigote and axenic amastigote forms and on intracellular amastigote forms of the parasites. Infectivity and cytotoxicity tests were carried on J774.2 macrophage cells using Glucantime as the reference drug. The mechanisms of action were analysed performing metabolite excretion and transmission electronic microscope ultrastructural alteration studies. Results. Nine flavonoids showed leishmanicidal activity against promastigote as well as amastigote forms of Leishmania infantum and L. braziliensis. These compounds were nontoxic to mammalian cells and were effective at similar concentrations up to or lower than that of the reference drug (Glucantime). The results showed that 2″-acetylpetiolaroside (compound 8) was clearly the most active. Conclusion. This study has demonstrated that flavonoid derivatives are active against L. infantum and L. braziliensis

The SELGIFS data challenge: generating synthetic observations of CALIFA galaxies from hydrodynamical simulations

In this work we present a set of synthetic observations that mimic the properties of the integral field spectroscopy (IFS) survey Calar Alto Legacy Integral-Field Area (CALIFA), generated using radiative transfer techniques applied to hydrodynamical simulations of galaxies in a cosmological context. The simulated spatially-resolved spectra include stellar and nebular emission, kinematic broadening of the lines, and dust extinction and scattering. The results of the radiative transfer simulations have been post-processed to reproduce the main properties of the CALIFA V500 and V1200 observational setups. The data has been further formatted to mimic the CALIFA survey in terms of field-of-view size, spectral range and sampling. We have included the effect of the spatial and spectral point spread functions affecting CALIFA observations, and added detector noise after characterizing it on a sample of 367 galaxies. The simulated data cubes are suited to be analysed by the same algorithms used on real IFS data. In order to provide a benchmark to compare the results obtained applying IFS observational techniques to our synthetic data cubes and test the calibration and accuracy of the analysis tools, we have computed the spatially-resolved properties of the simulations. Hence, we provide maps derived directly from the hydrodynamical snapshots or the noiseless spectra, in a way that is consistent with the values recovered by the observational analysis algorithms. Both the synthetic observations and the product data cubes are public and can be found in the collaboration website http://astro.ft.uam.es/selgifs/data_challenge/.Fil: Guidi, G.. Leibniz Institute For Astrophysics Potsdam; AlemaniaFil: Casado, J.. Consejo Superior de Investigaciones Científicas; España. Universidad Autónoma de Madrid; España. Leibniz Institute For Astrophysics Potsdam; AlemaniaFil: Ascasibar, Y.. Universidad Autónoma de Madrid; España. Consejo Superior de Investigaciones Científicas; EspañaFil: García Benito, R.. Consejo Superior de Investigaciones Científicas; España. Instituto de Astrofísica de Andalucía; EspañaFil: Galbany, L.. University of Pittsburgh; Estados UnidosFil: Sánchez Blázquez, P.. Consejo Superior de Investigaciones Científicas; España. Universidad Autónoma de Madrid; España. Pontificia Universidad Católica de Chile; ChileFil: Sánchez, S.F.. Universidad Nacional Autónoma de México; MéxicoFil: Rosales-Ortega, F.F.. Instituto Nacional de Astrofísica, Óptica y Electrónica; MéxicoFil: Scannapieco, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina. Leibniz Institute For Astrophysics Potsdam; Alemani

Patterns on the numerical duplication by their admissibility degree

We develop the theory of patterns on numerical semigroups in terms of the admissibility degree. We prove that the Arf pattern induces every strongly admissible pattern, and determine all patterns equivalent to the Arf pattern. We study patterns on the numerical duplication $S \Join^d E$ when $d \gg0$. We also provide a definition of patterns on rings

Low-temperature oxidation effects on the morphological and structural properties of hexagonal Zn nanodisks

Ambient-atmosphere oxidation in the temperature range of 90-450 C was performed over Zn films composed by well-faceted hexagonal nanodisks, which were deposited by thermal evaporation. Morphological and structural properties of oxidized Zn nanodisks were studied by scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and Raman scattering measurements. It was found that Zn nanodisks keep its original shape only when they are annealed at 90 or 150 C. Smooth oxidation ocurred only on the rectangular faces of Zn nandodisks heated at 150 C. Thermal oxidation at 250 C favored growth of ZnO nanoneedles over the surface of the Zn nanodisks. Hexagonal-shape of Zn nanodisks was transformed completely into a complex morphology composed by different shaped particles, with further increase in oxidation temperature to 450 C

Central star formation and metallicity in CALIFA interacting galaxies

We use optical integral-field spectroscopic (IFS) data from 103 nearby galaxies at different stages of the merging event, from close pairs to merger remnants provided by the CALIFA survey, to study the impact of the interaction in the specific star formation and oxygen abundance on different galactic scales. To disentangle the effect of the interaction and merger from internal processes, we compared our results with a control sample of 80 non-interacting galaxies. We confirm the moderate enhancement (2-3 times) of specific star formation for interacting galaxies in central regions as reported by previous studies; however, the specific star formation is comparable when observed in extended regions. We find that control and interacting star-forming galaxies have similar oxygen abundances in their central regions, when normalized to their stellar masses. Oxygen abundances of these interacting galaxies seem to decrease compared to the control objects at the large aperture sizes measured in effective radius. Although the enhancement in central star formation and lower metallicities for interacting galaxies have been attributed to tidally induced inflows, our results suggest that other processes such as stellar feedback can contribute to the metal enrichment in interacting galaxies.Comment: 9 pages, 9 figures. Accepted for publication in Astronomy & Astrophysic

Forage production and quality of common vetch mixtures with barley, oat and triticale in four phenological stages

Para determinar la producción y la calidad del forraje de la mezcla de veza común con cebada, avena, y triticale en dos proporciones de semilla (65:35; 35:65) durante cuatro etapas fenológicas, se estableció un experimento en un diseño de bloques completos al azar con arreglo factorial (3x4x4) con cuatro repeticiones. En mezclas de cultivos la mayor producción de materia seca (MS) la obtuvo la asociación avena-veza con 16.6 t ha-1 y en proporción de cultivos la avena-veza (65:35) produjo 19.9 t ha-1, durante la etapa grano masoso (P<0.001). La mayor cantidad de proteína cruda la obtuvieron las mezclas avena-veza (178 g kg-1 MS) y triticale-veza (161 g kg-1 MS) durante la etapa de embuche. Los menores valores de fibra detergente neutra los presentaron el monocultivo veza y su mezcla con avena (35:65), durante la etapa grano maduro (P<0.001). Las menores cantidades de fibra detergente ácida lo obtuvieron los monocultivos avena, veza y triticale durante la etapa grano lechoso (P<0.001). El mayor porcentaje de nutrientes digestibles totales lo obtuvo el monocultivo veza y su mezcla con cebada (65:35) durante la etapa grano lechoso, respectivamente (P<0.001). El contenido de energía neta de lactación y el valor relativo de forraje fue mayor para el monocultivo veza (P<0.001). Se concluye que la producción y calidad del forraje en mezcla de veza con cereales (cebada, avena y triticale) dependen de la etapa de cosecha. En este estudio, la mezcla avena-veza logró mayor producción de materia seca y mejor contenido de proteína cruda. Además, el valor relativo del forraje fue más alto durante la etapa grano maduro.The objective was to determine forage yield and quality of vetch mixtures with barley, oat and triticale in two seeding ratios (65:35; 35:65) at four phenological stages. To this end, a randomized block design with factorial array (3x4x4) and four replications was established. The greatest dry matter yield was obtained from the oat-vetch mixture at the grain doughy stage of maturity (16.6 t ha-1; P<0.00), while the seed proportion with the highest production was from the oat-vetch (65:35) ratio with 19.9 t ha-1 during the dough grain stage. The highest amount of crude protein was obtained from the oat-vetch (178 g kg-1 MS) and triticale-vetch (161 g kg-1 MS) mixtures during booting stage. The monoculture vetch and oats-vetch (35:65) proportion, both had lower amounts of neutral detergent fiber at the mature grain stage (P<0.001). The oat, vetch and triticale monocultures showed the lowest acid detergent fiber during milky grain stage (P<0.001). The greatest percentage of TDN was observed in vetch monoculture and its mixtures with barley (65:35) during the milky grain stage, respectively (P<0.001). The monoculture vetch provided highest values for NEL and RFV (P<0.001). In conclusion, the forage yield and quality of vetch mixtures with barley, oat and triticale depend on the maturity stage. Also, the oat-vetch mixture showed the greatest dry matter yield and high CP concentration. In addition, forage relative value was higher during the mature grain stage

First survey of Wolf-Rayet star populations over the full extension of nearby galaxies observed with CALIFA

The search of extragalactic regions with conspicuous presence of Wolf-Rayet (WR) stars outside the Local Group is challenging task due to the difficulties in detecting their faint spectral features. In this exploratory work, we develop a methodology to perform an automated search of WR signatures through a pixel-by-pixel analysis of integral field spectroscopy (IFS) data belonging to the Calar Alto Legacy Integral Field Area survey, CALIFA. This technique allowed us to build the first catalogue of Wolf-Rayet rich regions with spatially-resolved information, allowing to study the properties of these complexes in a 2D context. The detection technique is based on the identification of the blue WR bump (around He II 4686 {\AA}, mainly associated to nitrogen-rich WR stars, WN) and the red WR bump (around C IV 5808 {\AA} and associated to carbon-rich WR stars, WC) using a pixel-by-pixel analysis. We identified 44 WR-rich regions with blue bumps distributed in 25 galaxies of a total of 558. The red WR bump was identified only in 5 of those regions. We found that the majority of the galaxies hosting WR populations in our sample are involved in some kind of interaction process. Half of the host galaxies share some properties with gamma-ray burst (GRB) hosts where WR stars, as potential candidates to being the progenitors of GRBs, are found. We also compared the WR properties derived from the CALIFA data with stellar population synthesis models, and confirm that simple star models are generally not able to reproduce the observations. We conclude that other effects, such as the binary star channel (which could extend the WR phase up to 10 Myr), fast rotation or other physical processes that causes the loss of observed Lyman continuum photons, are very likely affecting the derived WR properties, and hence should be considered when modelling the evolution of massive stars.Comment: 33 pages, accepted for publication in A&