86, 43, and 22 GHz VLBI Observations of 3C120

We present the first 86 GHz VLBI observations of the radio galaxy 3C~120, together with contemporaneous 43 and 22 GHz polarimetric VLBA observations. The very high angular resolution obtained at 86 GHz provides an upper limit to the size of the core of 54 $\mu$as (0.025 $h^{-1}$pc). This represents a direct determination of the base of the jet which is independent of variability arguments (which depend on uncertain estimates of the Doppler factor), and places it below approximately one light-month. Comparison with previous VLBA observations after a one-year interval shows pronounced changes in the structure and polarization of the jet. Most of the components are found to follow a curved path while undergoing a steepening of their spectra accompanied by a decrease in total and polarized emission. However, at least one component is observed to follow a quasi-ballistic motion, accompanied by a flattening of its spectrum, as well as an increase in total and polarized flux. This may be explained by its interaction with the external medium, resulting in a shock that enhances the emission and aligns the magnetic field perpendicular to the component motion, thereby producing an increase of the degree of polarization from undetected values to as high as 15%. A second strong component, with the highest degree of polarization (23%), is found to have experienced a displacement from the ridge line of the structural position angle of the jet as it moved downstream. We have found a mean swing to the south of the position angle of the innermost components of $\sim 6^{\circ}$ between late 1996 and 1997, which may be responsible for the jet curvature observed at parsec and kiloparsec scales.Comment: 12 pages, 1 figure. Accepted for publication in ApJ Letter

Monthly 43 GHz VLBA Polarimetric Monitoring of 3C120 over 16 Epochs: Evidence for Trailing Shocks in a Relativistic Jet

We present a 16-month sequence of monthly polarimetric 43 GHz VLBA images of the radio galaxy 3C 120. The images probe the inner regions of the radio jet of this relatively nearby superluminal radio galaxy at a linear resolution of 0.07 $h_{65}^{-1}$ pc ($H_o= 65 h_{65}$ km s$^{-1}$ Mpc$^{-1}$). We follow the motion of a number of features with apparent velocities between 4.01$\pm$0.08 and $5.82\pm 0.13 h_{65}^{-1} c$. A new superluminal knot, moving at $4.29\pm 0.16 h_{65}^{-1} c$, is observed to be ejected from the core at a time coincident with the largest flare ever observed for this source at millimeter wavelengths. Changes in the position angle of this component, as well as a progressive rotation of its magnetic polarization vector, suggest the presence of a twisted (resembling a helix in projection) configuration of the underlying jet magnetic field and jet geometry. We identify several knots that appear in the wake of the new superluminal component, moving at proper motions $\sim 4$ times slower than any of the other moving knots observed in 3C 120. These features have properties similar to those of the ``trailing'' shocks seen in relativistic, time-dependent, hydrodynamical and emission simulations of compact jets. Such trailing compressions are triggered by pinch-mode jet-body instabilities caused by the propagation of a strong perturbation, which we associate with the new strong superluminal component.Comment: 4 pages, 5 figures, accepted for publication in Astrophysical Journal Letter

An orchestrated intron retention program in meiosis controls timely usage of transcripts during germ cell differentiation

Global transcriptome reprogramming during sper-matogenesis ensures timely expression of factors in each phase of male germ cell differentiation. Sper-matocytes and spermatids require particularly exten-sive reprogramming of gene expression to switch from mitosis to meiosis and to support gamete morphogenesis. Here, we uncovered an extensive alternative splicing program during this transmeiotic differentiation. Notably, intron retention was largely the most enriched pattern, with spermatocytes showing generally higher levels of retention compared with spermatids. Retained introns are characterized by weak splice sites and are enriched in genes with strong relevance for gamete func-tion. Meiotic intron-retaining transcripts (IRTs) were exclusively localized in the nucleus. However, differ-ently from other developmentally regulated IRTs, they are stable RNAs, showing longer half-life than properly spliced transcripts. Strikingly, fate-mapping experiments revealed that IRTs are recruited onto polyribosomes days after synthesis. These studies reveal an unexpected function for regulated intron retention in modulation of the timely expression of select transcripts during spermatogenesis

Jet stability and the generation of superluminal and stationary components

We present a numerical simulation of the response of an expanding relativistic jet to the ejection of a superluminal component. The simulation has been performed with a relativistic time-dependent hydrodynamical code from which simulated radio maps are computed by integrating the transfer equations for synchrotron radiation. The interaction of the superluminal component with the underlying jet results in the formation of multiple conical shocks behind the main perturbation. These trailing components can be easily distinguished because they appear to be released from the primary superluminal component, instead of being ejected from the core. Their oblique nature should also result in distinct polarization properties. Those appearing closer to the core show small apparent motions and a very slow secular decrease in brightness, and could be identified as stationary components. Those appearing farther downstream are weaker and can reach superluminal apparent motions. The existence of these trailing components indicates that not all observed components necessarily represent major perturbations at the jet inlet; rather, multiple emission components can be generated by a single disturbance in the jet. While the superluminal component associated with the primary perturbation exhibits a rather stable pattern speed, trailing components have velocities that increase with distance from the core but move at less than the jet speed. The trailing components exhibit motion and structure consistent with the triggering of pinch modes by the superluminal component.Comment: Accepted by ApJ Letters. LaTeX, 19 pages, 4 PostScript figure

Tunable class AB CMOS Gm-C channel filter for a bluetooth zero-IF receiver

A novel tunable third order low-pass Gm-C filter is introduced. Programmable transconductors operating in class AB have been used for its implementation hence featuring low quiescent power consumption. The operation in class AB is achieved using quasi-floating gate transistors. This filter is suitable for channel filtering of highly integrated, ultra low power wireless receivers e.g. for Bluetooth and Zigbee. Measurement results for a test chip prototype in a low-cost 0.5µm standard CMOS process are presented

Complicaciones torácicas en un paciente con luxación subclavicular del hombro

Se presenta una paciente de 88 años de edad con una luxación subclavicular de hombro derecho y un traumatismo torácico asociado que incluía fractura de las tres primeras costillas y hemotórax. El traumatismo torácico parecía estar muy estrechamente relacionado con la luxación glenohumeral. El tratamiento de la luxación se efectuó mediante reducción cerrada e inmovilización con vendaje de Gilchrist. El traumatismo del hemitórax derecho requirió toracocentesis en 2 ocasiones e ingreso en la unidad de cuidados intensivos por insuficiencia respiratoria. La evolución fue satisfactoria, estando la paciente asintomática a los 3 meses del traumatismo, con movilidad del hombro prácticamente completa.The case of a 88-year-old women with a subclavicular right shoulder dislocation and concomitant thoracic trauma involving fracture of the three first ribs and hemothorax is reported. The thoracic trauma appeared to be closely related to the shoulder dislocation. Close reduction and Gilchrist's immovilization was the treatment applied to the shoulder dislocation. Right thoracic trauma required evacuation of the hemothorax in two ocasions and inward in the Intensive Care Unit. Three months after trauma, the outcome was satisfactory with almost complete recovery of the shoulder range of motion

Comparison of micrometeorological techinques for estimating ammonia emission from covered slurry storage and land spreading of cattle slurry

The micrometeorological mass-balance integrated horizontal flux (IHF) technique has been commonly employed for measuring ammonia (NH3) emissions inon-field experiments. However, the inverse-dispersion modeling technique, such as the backward Lagrangian stochastic (bLS) modeling approach, is currently highlighted as offering flexibility in plot design and requiring a minimum number of samplers (Ro et al., 2013). The objective of this study was to make a comparison between the bLS technique with the IHF technique for estimating NH3 emission from flexible bag storage and following landspreading of dairy cattle slurry. Moreover, considering that NH3 emission in storage could have been non uniform, the effect on bLS estimates of a single point and multiple downwind concentration measurements was tested, as proposed by Sanz et al. (2010)

Accesibilidad y turismo en el parque nacional de Monfragüe

En los últimos años ha habido un aumento espectacular de la demanda de turismo en espacios naturales protegidos, en el caso de España esa demanda se cifra en aproximadamente 10 millones de visitantes. Al tiempo, también se ha incrementado el turismo llevado a cabo por personas con algún tipo de discapacidad, siendo éste un segmento de mercado que alcanza en España cerca de 3,5 millones de personas, en Europa 50 millones y en el mundo alrededor de 500 millones. Si partimos de la premisa de que toda persona tiene derecho a disfrutar del medio ambiente, las áreas de uso público de los espacios naturales protegidos deberían ir adaptándose y normalizándose para un uso social generalizado de las mismas. En este trabajo se presentan las principales conclusiones del proyecto de investigación “Las áreas de uso público en la Reserva de la Biosfera de Monfragüe. Accesibilidad y capacidad de carga” (Orden MAM 321/2007; No Exp. 024/SGTB/2007 4.1), que ponen de relieve las principales necesidades en materia de accesibilidad y adaptación de las mismas para permitir que el uso público tenga un carácter universal.In the last years there has been a spectacular increase of the demand of tourism in natural protected spaces, in case of Spain this demand codes in approximately 10 millions of visitors. To the time, also there has been increased the tourism carried out by persons with some type of disability, being this one a segment of market that reaches in Spain near 3,5 million persons, in Europe 50 million and in the world about 500 million. If we depart from the premise from that every person has right to enjoy the environment, the areas of public use of the natural protected spaces should go adapting and settling down for a social widespread use of the same ones. In this work they present the principal conclusions of the project of investigation "The areas of public use in the Reserve of Monfragüe's Biosphere. Accessibility and capacity of load" (Order MAM 321/2007; N o Exp. 024/SGTB/2007 4.1), that emphasize the principal needs as for accessibility and adjustment of the same ones to allow that the public use should have a universal character.Secretaría general de empleo, actividad empresarial e innovación tecnológica del Gobierno de Extremadura. Ayuda a los grupos de investigación catalogados (Ref.: 2010/00491/001