Interpreting the time variable RM observed in the core region of the TeV blazar Mrk 421

In this work we interpret and discuss the time variable rotation measure (RM) found, for the first time over a 1-yr period, in the core region of a blazar. These results are based on a one-year, multi-frequency (15, 24, and 43 GHz) Very Long Baseline Array (VLBA) monitoring of the TeV blazar Markarian 421 (Mrk 421). We investigate the Faraday screen properties and its location with respect to the jet emitting region. Given that the 43 GHz radio core flux density and the RM time evolution suggest a similar trend, we explore the possible connection between the RM and the accretion rate. Among the various scenarios that we explore, the jet sheath is the most promising candidate for being the main source of Faraday rotation. During the one-year observing period the RM trend shows two sign reversals, which may be qualitatively interpreted within the context of the magnetic tower models. We invoke the presence of two nested helical magnetic fields in the relativistic jet with opposite helicities, whose relative contribution produce the observed RM values. The inner helical field has the poloidal component ($B_{\rm p}$) oriented in the observer's direction and produces a positive RM, while the outer helical field, with $B_{\rm p}$ in the opposite direction, produces a negative RM. We assume that the external helical field dominates the contribution to the observed RM, while the internal helical field dominates when a jet perturbation arises during the second observing epoch. Being the intrinsic polarization angle parallel to the jet axis, a pitch angle of the helical magnetic field $\phi\gtrsim 70^\circ$ is required. Additional scenarios are also considered to explain the observed RM sign reversals.Comment: 6 pages, 2 figures. Published on MNRA

Release experiments with Octopus vulgaris Cuvier, 1797 in Galicia, NW Spain. First results on recapture rate, distribution and growth.

This paper describes the release experiments carried out with 465 octopus (Octopus vulgaris Cuvier, 1797) with an average weight ranging from 703 to 986 g in three different areas in the Ría of Vigo, Galicia, NW Spain. Thirty-seven individuals were recaptured by fishermen, representing a total recapture rate of 7.9 %. Among these, 80.5 % remained within 5 km of the release point, showing a sedentary behavior. The specific growth rate (SGR) in weight was 0.00902 ± 0.00468; there was not a significant difference between males and females. The exponential growth curve is the best fitting theoretical model. Life expectancy in Ría de Vigo waters was estimated at 18 months for males, and 16 months for females. Throughout the recapture process, males were predominant over females, giving a sex ratio of 1.83:1. Data reported in this paper on recapture rate, sedentary behavior and instantaneous growth rate can be used as reference for future stocking programs in Galicia

Culture viability of Sarddina pilchardus: preliminary results of growth in captivity

Larvae of Sardina pilchardus were obtained in captivity from fertilized eggs captured in the wild, and grown in a 10 000 L tank. Isochrysis galbana , Artemia franciscana nauplii and live zooplankton were used as prey during the first two weeks; afterwards, anim als were fed on artemia metanauplius enriched with Isochrysis galbana . A dry feed (Gemma 0.4 and 0.8) from SKRETTING S.A. (Burgos, España) was supplied from the third to 18th month. The total length reached by sardines at one year of life was 162.02 ± 9. 49 mm, corresponding to a wet weight of 36.12 ± 10.82 g. Total length at 18 months was 182.37 mm. A long experiment (18 ‐ month) of sardine culture is described for the first time, and growth data reported can contribute to determine its potential interest as a candidate for marine aquacultur

Culture viability of Sardine pilchardus (Fish, teleost): Preliminary results of growth in captivity up to 18 months

Larvae of Sardina pilchardus were obtained in captivity from fertilized eggs captured in the wild and grown in a 10000-L tank. Isochrysis galbana, Artemia franciscana nauplii and live zooplankton were used as prey during the first two weeks; afterwards, the animals were fed on Artemia metanauplii enriched with Isochrysis galbana. A dry feed (Gemma 0.4 and 0.8) from Skretting S.A. (Burgos, España) was supplied from the 3rd to the 18th month. The total length reached by sardines at one year of life was 162.02±9.49 mm, corresponding to a wet weight of 36.12±10.82 g. Total length of the last survivor individual at 18 months was 182.37 mm. An 18-month experiment of sardine culture is described for the first time, and the growth data reported can help to determine its potential as a candidate for marine aquaculture.Publicado

Management of incidentally detected heart murmurs in dogs and cats

A dog or a cat has an incidentally detected heart murmur if the murmur is an unexpected discovery during a veterinary consultation that was not initially focused on the cardiovascular system. This document presents approaches for managing dogs and cats that have incidentally-detected heart murmurs, with an emphasis on murmur characteristics, signalment profiling, and multifactorial decision-making to choose an optimal course for a given patient