The Dwarf Galaxy Population of the Dorado group down to Mv=-11

We present V and I CCD photometry of suspected low-surface brightness dwarf galaxies detected in a survey covering ~2.4 deg^2 around the central region of the Dorado group of galaxies. The low-surface brightness galaxies were chosen based on their sizes and magnitudes at the limiting isophote of 26.0V\mu. The selected galaxies have magnitudes brighter than V=20 (Mv=-11 for an assumed distance to the group of 17.2 Mpc), with central surface brightnesses \mu0>22.5 V mag/arcsec^2, scale lengths h>2'', and diameters > 14'' at the limiting isophote. Using these criteria, we identified 69 dwarf galaxy candidates. Four of them are large very low-surface brightness galaxies that were detected on a smoothed image, after masking high surface brightness objects. Monte Carlo simulations performed to estimate completeness, photometric uncertainties and to evaluate our ability to detect extended low-surface brightness galaxies show that the completeness fraction is, on average, > 80% for dwarf galaxies with $-17<M_{V}<-10.5$ and 22.5<\mu0<25.5 V mag/arcsec^2, for the range of sizes considered by us (D>14''). The V-I colors of the dwarf candidates vary from -0.3 to 2.3 with a peak on V-I=0.98, suggesting a range of different stellar populations in these galaxies. The projected surface density of the dwarf galaxies shows a concentration towards the group center similar in extent to that found around five X-ray groups and the elliptical galaxy NGC1132 studied by Mulchaey and Zabludoff (1999), suggesting that the dwarf galaxies in Dorado are probably physically associated with the overall potential well of the group.Comment: 32 pages, 16 postscript figures and 3 figures in GIF format, aastex v5.0. To appear in The Astronomical Journal, January 200

Removal of lead, mercury and nickel using the yeast Saccharomyces cerevisiae

Objective. In this study the biomass of the yeast Saccharomyces cerevisiae was used to remove lead, mercury and nickel in the form of ions dissolved in water. Materials and methods. Synthetic solutions were prepared containing the three heavy metals, which were put in contact with viable microorganisms at different conditions of pH, temperature, aeration and agitation. Results. Both individual variables and the interaction effects influenced the biosorption process. Throughout the experimental framework it was observed that the biomass of Saccharomyces cerevisiae removed a higher percentage of lead (86.4%) as compared to mercury and nickel (69.7 and 47.8% respectively). When the pH was set at a value of 5 the effect was positive for all three metals. Conclusions. pH was the variable that had a greater influence on the biosorption of lead on the biomass of Saccharomyces cerevisiae. The affinity of the heavy metals for the biomass followed the order Pb>Hg>Ni

Formación en Cinemática y Dinámica de Sistemas Multicuerpo Mediante Coordenadas Naturales

La formación de los futuros ingenieros mecánicos en dinámica de sistemas multicuerpo 3-D rara vez encuentra una materia específica en los planes de estudio, ni siquiera en postgrado. Cuando sólo se dispone de algunas horas (entre 5 y 10 horas de clase y unas 15 de trabajo personal) en el marco de una materia más general, las coordenadas naturales y Matlab son probablemente el único camino para alcanzar ciertos objetivos prácticos. Aquí se aborda cómo se pueden alcanzar estos objetivos, con un aprendizaje basado en .casos reales. Very often, the curriculum of mechanical engineers doesn't include any specific subject on kinematics and dynamics of multibody systems. In these situations the unique opportunity to introduce MBS is to dedicate from 5 to 10 hours to this subject inside a more general course, plus about 15 hours of personal work. This paper shows how this short time can be enough if natural coordinates are used. Keywords

Multiaperture UBVRIzJHKUBVRIzJHK Photometry of Galaxies in the Coma Cluster

We present a set of $UBVRIzJHK_s$ photometry for 745 $J+H$ band selected objects in a $22.5' \times 29.2'$ region centered on the core of the Coma cluster. This includes 516 galaxies and is at least 80% complete to H=16, with a spectroscopically complete sample of 111 cluster members (nearly all with morphological classification) for $H < 14.5$. For each object we present total \cite{kron80} magnitudes and aperture photometry. As an example, we use these data to derive color-magnitude relations for Coma early-type galaxies, measure the intrinsic scatter of these relations and its dependence on galaxy mass, and address the issue of color gradients. We find that the color gradients are mild and that the intrinsic scatter about the color-magnitude relation is small ($\sim 0.05$ mag in $U-V$ and less than $\sim 0.03$ in $B-R$, $V-I$ or $J-K$). There is no evidence that the intrinsic scatter varies with galaxy luminosity, suggesting that the cluster red sequence is established at early epochs over a range of $\sim 100$ in stellar mass.Comment: 41 pages, 5 figures, 18 data tables attached to source files or available on request from R. De propris. Accepted for publication in Astrophysical Journal Supplement Serie

Producción de fórmulas para la vacunación oral de salmónidos contra Piscirickettsia salmonis

La acuicultura ha experimentado en los últimos años un notable aumento en la producción debido al crecimiento de la población mundial y la necesidad de satisfacer la demanda de productos alimentarios. Como consecuencia de esta gran expansión también se ha favorecido la aparición de nuevas enfermedades que afectan a este sector. Un ejemplo concreto lo encontramos en la industria salmónida chilena, que se ha visto afectada por una enfermedad producida por Septicemia rickettsial salmonídea (SRS) o piscirickettsiosis provocada por la bacteria gram negativa Piscirickettsia salmonis. La enfermedad causa pérdidas económicas en Chile valoradas en 100 millones de dólares anuales, debido a muerte de salmones, pérdida de calidad del producto y coste del tratamiento. Actualmente los tratamientos para combatir la infección no son eficaces, por lo que un método de vacunación eficaz, seguro y económicamente sostenible se presenta como una alternativa deseada por el sector.  Bionaturis propone una solución basada en desarrollar fórmulas para la vacunación vía oral conteniendo como principio activo una proteína de la membrana de P. salmonis que ha demostrado previamente protección tras la administración vía oral de una versión preparada en bacterias. Las fórmulas de Bionaturis se basan en la producción en biofactorías consistentes en larvas de lepidóptero. El candidato producido anteriomente por terceros en bacterias no es económicamente viable debido al gran volumen de fermentación necesario para producir las dosis requeridas para el tratamiento oral de los salmónidos. Con el objetivo final de evaluar el rendimiento cuantitativo y cualitativo de las biofactorías de Bionaturis, en este proyecto hemos diseñado dos versiones del principio activo basadas en la secuencia de la proteína de membrana fusionada a secuencias inmunomoduladoras y a secuencias para evitar la degradación durante el formulado en el alimento y tras la administración a peces. Se produjeron dos versiones de baculovirus recombinantes basados en el ADN de AcMNPV, que fueron titulados y caracterizados. El producto de la expresión de los baculovirus se caracterizó en células de insecto Sf21. Posteriormente la experimentación se ha basado en optimizar las variables para producir las fórmulas finales en larvas de insecto, con el objeto de evaluar su eficacia in vivo en salmónidos por una empresa interesada en completar el desarrollo del producto

Clustering of red galaxies around the z=1.53 quasar 3C270.1

In the paradigm of hierarchical galaxy formation, luminous radio galaxies mark mass assembly peaks that should contain clusters of galaxies. Observations of the z=1.53 quasar 3C270.1 with the Spitzer Space Telescope at 3.6-24 micron and with the 6.5-m MMT in the z'- and Y-bands allow detection of potential cluster members via photometric redshifts. Compared with nearby control fields, there is an excess of 11 extremely red objects (EROs) at 1.33 < z_phot < 1.73, consistent with a proto-cluster around the quasar. The spectral energy distributions (SEDs) of 3/4 of the EROs are better fitted with passive elliptical galaxies than withdust-reddened starbursts, and of four sources well-detected on an archival HST snapshot image, all have undisturbed morphologies. However, one ERO, not covered by the HST image, is a double source with 0.8" separation on the z' image and a marginal (2sigma) 24 micron detection indicating a dust-enshrouded starburst. The EROs are more luminous than L* (H = -23.6 AB mag at z=1.5).Comment: 12 pages, 7 figures, accepted by Ap

Novel Fast Catadioptric Objective with Wide Field of View

Using the Simultaneous Multiple Surface method in 2D (SMS2D), we present a fast catadioptric objective with a wide field of view (125°×96°designed for a microbolometer detector with 640×480 pixels and 25 microns pixel pitc

Exequibilidade, segurança e utilidade da biópsia endomiocárdica ventricular esquerda por acesso transradial : experiência inicial de um centro universitário terciário

© 2020 Sociedade Portuguesa de Cardiologia. Published by Elsevier España, S.L.U. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/bync-nd/4.0/).Introduction and objectives: Over the last decade, several studies have suggested that left ventricular endomyocardial biopsy is safer and has a higher diagnostic yield than transvenous right ventricular biopsy. In addition, recent publications indicate that the transradial approach is a feasible and safe alternative to the transfemoral approach for sampling the left ventricle. We report our initial experience with transradial endomyocardial biopsy with regards to feasibility, safety and usefulness. Methods: Single-center registry of consecutive patients undergoing intended transradial left endomyocardial biopsy. Clinical and technical data were collected prospectively, with a particular focus on success rate and complications. Results: Twenty-seven patients were screened for left ventricle biopsy. Twenty (25) were selected for an intended transradial approach (mean age 51±18 years old, 22 male). Success rate was 100% with no crossover to femoral approach. There were no major complications. Two patients experienced mild radial spasm. One of them also had a run of non-sustained ventricular tachycardia. Indication for biopsy was either myocarditis or cardiomyopathy of unknown etiology. The final diagnosis was acute lymphocytic myocarditis in five patients, chronic myocarditis in one patient, amyloid light-chain amyloidosis in four patients and transthyretin amyloidosis in six patients. Myocarditis was ruled out in eight patients and amyloidosis in one patient. Conclusions: Transradial left ventricle endomyocardial biopsy is a very safe and feasible method of sampling the myocardium for histopathological analysis, with a good diagnostic yield and clinically meaningful results in properly selected patients.info:eu-repo/semantics/publishedVersio