HS 0139+0559, HS 0229+8016, HS 0506+7725, and HS 0642+5049 : four new long-period cataclysmic variables

We present time-resolved optical spectroscopy and photometry of four relatively bright (V ∼ 14.0−15.5) long-period cataclysmic variables(CVs) discovered in the Hamburg Quasar Survey: HS 0139+0559, HS 0229+8016, HS 0506+7725, and HS 0642+5049. Their respective orbital periods, 243.69 ± 0.49 min, 232.550 ± 0.049 min, 212.7 ± 0.2 min, and 225.90 ± 0.23 min are determined from radial velocity and photometric variability studies. HS 0506+7725 is characterised by strong Balmer and He emission lines, short-period (∼10−20 min) flickering, and weak X-ray emission in the ROSAT All Sky Survey. The detection of a deep low state (B 18.5) identifies HS 0506+7725 as a member of the VY Scl stars. HS 0139+0559, HS 0229+8016, and HS 0642+5049 display thick-disc like spectra and no or only weak flickering activity. HS 0139+0559 and HS 0229+8016 exhibit clean quasi-sinusoidal radial velocity variations of their emission lines but no or very little orbital photometricvariability. In contrast, we detect no radial velocity variation in HS 0642+5049 but a noticeable orbital brightness variation. We identify all three systems either as UX UMa-type novalike variables or as Z Cam-type dwarf novae. Our identification of these four new systems underlines that the currently known sample of CVs is rather incomplete even for bright objects. The four new systems add to the clustering of orbital periods in the 3−4 h range found in the sample of HQS selected CVs, and we discuss the large incidence of magnetic CVs and VY Scl/SW Sex stars found in this period range among the known population of CVs

V348 Puppis: a new SW Sex star in the period gap

We present time-resolved optical spectroscopy and photometry of the nova-like cataclysmic variable V348 Puppis. The system displays the same spectroscopic behaviour as SW Sex stars, so we classify V348 Pup as a new member of the class. V348 Pup is the second SW Sex system (the first is V795 Herculis) which lies in the period gap. The spectra exhibit enhanced HeII 4686 emission, reminiscent of magnetic cataclysmic variables. The study of this emission line gives a primary velocity semi-amplitude of K1 ~= 100 km/s. We have also derived the system parameters, obtaining: M1 ~= 0.65 Msun, M2 ~= 0.20 Msun (q ~= 0.31), i ~= 80 deg and K2 ~= 323 km/s. The spectroscopic behaviour of V348 Pup is very similar to that of V795 Her, with the exception that V348 Pup shows deep eclipses. We have computed the ``0.5-absorption'' spectrum of both systems, obtaining spectra which resemble the absorption spectrum of a B0 V star. We propose that absorption in SW Sex systems can be produced by a vertically extended atmosphere which forms where the gas stream re-impacts the system, either at the accretion disc or at the white dwarf's magnetosphere (assuming a magnetic scenario).Comment: 6 pages, 10 figures, accepted for publication in MNRA

The redshift and broad band spectral energy distribution of NRAO 150

Context. NRAO 150 is one of the brightest radio and mm AGN sources on the northern sky. It has been revealed as an interesting source where to study extreme relativistic jet phenomena. However, its cosmological distance has not been reported so far, because of its optical faintness produced by strong Galactic extinction. Aims. Aiming at measuring the redshift of NRAO 150, and hence to start making possible quantitative studies from the source. Methods. We have conducted spectroscopic and photometric observations of the source in the near-IR, as well as in the optical. Results. All such observations have been successful in detecting the source. The near-IR spectroscopic observations reveal strong H$\alpha$ and H$\beta$ emission lines from which the cosmological redshift of NRAO 150 ($z=1.517\pm0.002$) has been determined for the first time. We classify the source as a flat-spectrum radio-loud quasar, for which we estimate a large super-massive black-hole mass $\sim5\times 10^{9} \mathrm{M_\odot}$. After extinction correction, the new near-IR and optical data have revealed a high-luminosity continuum-emission excess in the optical (peaking at $\sim2000$\,\AA, rest frame) that we attribute to thermal emission from the accretion disk for which we estimate a high accretion rate, $\sim30$\,% of the Eddington limit. Conclusions. Comparison of these source properties, and its broad-band spectral-energy distribution, with those of Fermi blazars allow us to predict that NRAO 150 is among the most powerful blazars, and hence a high luminosity -although not detected yet- $\gamma$-ray emitter.Comment: 8 pages, 4 figure

La vida en un laboratorio de alta seguridad biológica

El trabajo e investigación con ciertos microorganismos puede suponer un gran riesgo tanto para el personal que trabaja con ellos, como para los animales y el medio ambiente. Ello hace necesaria la existencia de laboratorios de alta seguridad biológica que permitan su estudio sin riesgo. En este tipo de laboratorios las medidas de bioseguridad son muy estrictas y ello puede afectar al personal que trabaja a diario en estos centros. Conocer cómo les afectan, en qué medida y por qué ha sido el objetivo principal de nuestro trabajo. Para ello se realizó y diseñó una encuesta que ha permitido recoger la opinión de los trabajadores de tres importantes centros de alta seguridad biológica dedicados a Sanidad Animal y Salud Pública. Tras el análisis de las respuestas se observó que la mayoría de encuestados encuentra factores limitantes para su trabajo en este tipo de centros, si bien estos varían de un centro a otro y no impiden valorar la necesidad de estas medidas.To work and research with some kind of microorganism could suppose a high risk for humans, animals and environment. This fact makes necessary the existence of biosafety laboratories. In this type of centres, high security conditions are very strict and that could affect people who work daily inside it. Knowing how it affects them is the main objective of our study. For that reason we have done a survey to know the impressions of people who work in laboratories of Biosafety level 3 (BSL-3) . After analyzing the results of this survey, we could say that working inside BSL-3 implies certain limitations for people who work inside them, but they respect and value the importance of this security conditions

Utilización de factores de crecimiento plaquetarios asociados a fosfato pentacálcico en el tratamiento de lesiones óseas paratumorales en la infancia

El tratamiento de las lesiones óseas paratumorales (como el quiste óseo aneurismático y el quiste óseo simple) continúa siendo controvertido. Aunque existen diferentes posibilidades de tratamiento, el porcentaje de fallo en la curación debido a recidivas de estas lesiones no es desdeñable. Los autores presentan su experiencia retrospectiva en 5 casos en diferentes localizaciones anatómicas, tratados mediante curetaje y relleno de la lesión mediante un sustituto óseo (fosfato pentacálcico, fibrina y factores de crecimiento autólogos derivados de plaquetas) con resultados satisfactorios.Treatment of tumorlike lesions of bone (as aneurysmal bone cyst and simple bone cyst) remains controversial. Although there are different possibilities of treatment, the rate of failure to cure due to recurrences of both types of lesions is not negligible. The authors present their retrospective experience in 5 cases in different locations, where such lesions were treated by means of curettage and grafting using a bone substitute (pentacalcium phosphate, fibrine and autologous platelet derived growth factors) with satisfactory results

Estudio de la biocompatibilidad de una nueva aleación beta-titanio de bajo módulo de elasticidad

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