Scalar field self-force effects on orbits about a Schwarzschild black hole

For a particle of mass mu and scalar charge q, we compute the effects of the scalar field self-force upon circular orbits, upon slightly eccentric orbits and upon the innermost stable circular orbit of a Schwarzschild black hole of mass M. For circular orbits the self force is outward and causes the angular frequency at a given radius to decrease. For slightly eccentric orbits the self force decreases the rate of the precession of the orbit. The effect of the self force moves the radius of the innermost stable circular orbit inward by 0.122701 q^2/mu, and it increases the angular frequency of the ISCO by the fraction 0.0291657 q^2/mu M.Comment: 15 pages, 8 figure

Millimagnitude Photometry for Transiting Extrasolar Planetary Candidates III: Accurate Radius and Period for OGLE-TR-111-b

We present accurate V-band photometry for a planetary transit of OGLE-TR-111 acquired with VIMOS at the ESO Very Large Telescope. The measurement of this transit allows to refine the planetary radius, obtaining R_p= 1.01 +/- 0.06 R_J. Given the mass of M_p = 0.53 M_J previously measured from radial velocities, we confirm that the density is rho_p= 0.6 +/- 0.2 g/cm^3. We also revise the ephemeris for OGLE-TR-111-b, obtaining an accurate orbital period P= 4.014484 +/- 0.000014 days, and predicting that the next observable transits would occur around December 2006, and after that only in mid-2008. Even though this period is different from previously published values, we cannot yet rule out a constant period.Comment: 16 pages (including figures), 5 figures, 1 table. Accepted for publication in the Astrophysical Journa

High seroprevalence of equine infectious anemia in workhorses from an endemic region in Northeast Argentina

La anemia infecciosa equina (AIE), también conocida como fiebre del pantano,es una enfermedad infecciosa causada por un virus ARN común en équidos,burros y mulas. Tiene una distribución mundial. El objetivo de este estudio fueinvestigar la prevalencia y la incidencia serológica de AIE en 118 caballos dela provincia de Corrientes, zona endémica del Nordeste Argentino, durante unperiodo de tres años (2014-2016). Se realizaron tres muestreos de un total de118 caballos de trabajo. Se obtuvieron muestras de sangre completa de cadacaballo y re-muestreos posteriores por punción yugular con agujas estériles,guantes y jeringas desechables. La prevalencia de AIE fue de 77,2% en 2014,81,3% en 2015 y 88,7% en 2016. La incidencia acumulada de la enfermedadfue de 0,30 en un año y de 0,35 en dos años. Considerando que la AIE es undesafío importante para los sistemas de producción de equinos en laArgentina, el éxito del control de la enfermedad requerirá el esfuerzo conjuntode autoridades sanitarias, veterinarios y propietarios de caballos.Equine infectious anemia (EIA), also known as swamp fever, is an infectious disease caused by an RNA virus common in equids, donkeys and mules. It has a worldwide distribution and is currently considered a global disease. The aim of this study was to investigate the serological incidence and prevalence of EIA in 118 horses from the province of Corrientes, an endemic area of Northeast Argentina, over three years (2014-2016). Three samplings of a total of 118 workhorses were performed. Whole blood samples of each horse and subsequent resamplings were obtained by jugular puncture with sterile needles, gloves and disposable syringes. EIA prevalence was 77.2% in 2014, 81.3% in 2015 and 88.7% in 2016. The accumulated incidence of the disease was 0.30 in one year and 0.35 in two years. Considering that EIA is a major challenge for equine production systems in Argentina, successful disease control will require the joint effort of sanitary authorities, veterinary practitioners and horse owners.Fil: Espasandin, Ana Gabriela. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cipolini, María F.. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; ArgentinaFil: Storani, Carlos A.. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; ArgentinaFil: Monzon, Nolly Maria. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; ArgentinaFil: Martínez, Diana. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; ArgentinaFil: Diaz, Silvina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; Argentin

Synthesis and characterization of smectite clay Zn-stevensite

Argila do grupo das esmectitas foi obtida com êxito em baixa temperatura de processamento por via hidrotérmica utilizando como precursores metassilicato de sódio, nitrato de zinco e uréia. Durante a etapa de síntese a composição molar da mistura reacional e a temperatura permaneceram constantes, variando-se o tempo de reação. As amostras sintetizadas foram caracterizadas por difração de raios X, microscopia eletrônica de varredura, espectroscopia de refletância difusa no infravermelho com transformada de Fourier, análise térmica diferencial e gravimétrica, análise de adsorção gasosa de nitrogênio pelo método BET e capacidade de troca de cátions. Os resultados evidenciam que com a metodologia empregada obtêm-se Zn-estevensita apresentando uma área superficial total na faixa de 171,6 a 203,4 m2/g e boa cristalinidade; sendo esta a única fase presente no produto sintetizado após reação estática a 90 ºC por um período de 44 a 138 h, indicando ser o aumento no tempo de síntese um parâmetro importante para o processo de cristalização da argila

The Luminosity Function of Magnitude and Proper-Motion Selected Samples. The case of White-Dwarfs

The luminosity function of white dwarfs is a powerful tool for studies of the evolution and formation of the Milky Way. The (theoretical) white dwarf cooling sequence provides a useful indicator of the evolutionary time scales involved in the chronometry and star formation history of the galactic disk, therefore, intrinsically faint (& old) white dwarfs in the immediate solar neighborhood can be used to determine an upper limit for the age of the galactic disk. In this paper we examine the faint-end ($M_V > +14$) behavior of the disk white dwarf luminosity function using the $1/V_{\rm max}$ method, but fully including the effects of realistic observational errors in the derived luminosity function. We employ a Monte Carlo approach to produce many different realizations of the luminosity function from a given data set with pre-specified and reasonable errors in apparent magnitude, proper-motions, parallaxes and bolometric corrections. These realizations allow us to compute both a mean and an expected range in the luminosity function that is compatible with the observational errors. We find that current state-of-the art observational errors, mostly in the bolometric corrections and trigonometric parallaxes, play a major role in obliterating (real or artificial) small scale fluctuations in the luminosity function. We also find that a better estimator of the true luminosity function seems to be the median over simulations, rather than the mean. When using the latter, an age for the disk of 10 Gyr or older can not be ruled out from the sample of Leggett, Ruiz, and Bergeron (1998).Comment: Manuscript AAS Latex macro v4.0, 33 pages, 13 postscript figures (Color in figs. 9 and 12). Accepted for publication in The Astrophysical Journal. Replaced by two-column version & indication of acceptance by the Ap

Cálculo de tasas de incisión a partir de travertinos fluviales. Aplicación a la gestión de residuos radiactivos

El estudio paleo ambiental y paleo climatológico de España, fue considerado parte del análisis de la seguridad de los repositorios de residuos radiactivos emprendida por ENRESA. La Unión Europea y distintas agencias nacionales, también comprendieron la importancia de este tema, contemplado en numerosos proyectos marco EURATOM y proyectos propios de ENRESA y del CSN en los que participó el Grupo de Estudios Ambientales a través del Laboratorio de Estratigrafía Biomolecular: Palaeoclimatological revisión of climate evolution in t he Western Mediterranean Región, Evidency from Quaternary Infills Palaeohydrogeology (EQUIP), Sequential biosphere modelling function of Climate evolution models (BIOCLIM), Paleohydrogeological Data Analysis and Model Testing (PADAMOT), Datación de formaciones cuaternarias a partir de aminoácidos (ENRESA), Estudio paleoambiental de la mitad sur de la Península Ibérica (ENRESA), Paleoclima (ENRESA y CSN

Decontamination of Diesel particles from air by using the Counterfog (R) system

The existence of particles with diameter under 10m in air is strongly correlated with respiratory diseases. These particles are profusely produced by heating systems, traffic, and Diesel engines creating a serious problem to modern cities. Natural mechanisms removing particles from the atmosphere are too slow to deal with the huge amount of particles daily released by human activity. The objective of this work is to measure the effectiveness of a new technology called Counterfog (R) to eliminate airborne particles. The results show that Counterfog (R) is able to wash out PM10, PM5, and PM2.5 Diesel-generated airborne particles quite efficiently.This work has been funded by the FP7-SEC-2012-1 program of the EU Commission under grant number 312804

Compuestos orgánicos presentes en aguas de escombreras de carbón.

Se ha realizado un estudio de la influencia de las aguas acidas de mina en la movilización de los hidrocarburos policidicos aromáticos (PAHs) presentes en las escombreras de carbón. Se observa como dichas aguas acidas disuelven preferentemente a los PAHs de menor peso molecular. También se ha realizado un análisis de riesgos que indica que existe un riesgo real por uso y consumo, en el interior de las viviendas, del agua subterránea. Por último, se han establecido las bases para una técnica pasiva, la foto degradación, de tratamiento de las aguas contaminadas con PAHs presentes en las escombreras de carbón