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Supermassive black hole binaries (SMBHBs) are natural by-products of galaxy mergers and are expected to be powerful multi-messenger sources. They can be powered by the accretion of matter and shine throughout the electromagnetic spectrum similarly to normal active galactic nuclei (AGNs). Current electromagnetic observatories have good chances to detect and identify these systems in the near future, but we need precise observational indicators to distinguish single AGNs from SMBHBs. In this work, we propose a novel electromagnetic signature from SMBHBs: periodic flares caused by the interaction between the jets launched by the black holes. We investigate close black hole binaries accreting matter from a circumbinary disc and the mini-discs formed around each hole, and launching magnetically-dominated jets in the direction of their spin through the Blandfor--Znajeck mechanism. If the spins are slightly inclined, the two jets will encounter each other once per orbit. We argue that this interaction may trigger strong magnetic reconnection events where particles are accelerated and form plasmoids that emit non-thermal radiation. We model the evolution of these particles and calculate the radiative output obtaining spectra and light curves at different wavelengths. We show that these flares can significantly shine in radio, soft X-rays, and \gamma rays, providing a periodic multi-wavelength electromagnetic signature for SMBHBs., Comment: 14 pages, 12 figures, submitted to MNRAS

Polyphagotarsonemus latus es una especie cosmopolita que afecta diferentes cultivos tanto en áreas templadas como tropicales. El principal daño ocasionado por esta especie es la reducción o deformación de hojas jóvenes, brotes, frutos y flores. Cuando P. latus se alimenta de hojas de papayo, éstas presentan clorosis y las hojas se enrollan. En México, el daño causado por este ácaro es conocido como "mano de chango" porque el área de las hojas de papayo se reduce casi hasta las nervaduras. Este daño es similar al causado por el Virus de la mancha anular del papayo (PRSVp). Debido a que P. latus y PRSV-p causan daños similares a las hojas de papayo, el objetivo de esta investigación fue determinar el efecto de P. latus, PRSV-p y su posible interacción en la reducción del área foliar en plantas de papayo. El diagnóstico de PRSV-p se realizó mediante RT-PCR. Los efectos producidos por P. latus fueron similares a los producidos por PRSV-p; sin embargo, éstos pueden diferenciarse por la zona que es atacada. Los daños de los ácaros sólo se encontraron en las hojas más jóvenes, la clorosis siempre comenzaba de la vena central hacia la parte terminal de los foliolos, a diferencia de la producida por el virus que podía presentarse en cualquier parte de la lámina foliar. La altitud y el diámetro de los tallos pueden verse afectados por la infestación de los ácaros, lo cual no sucede con la presencia del virus. Polyphagotarsonemus latus is a cosmopolitan species that affects several crops in tropical and temperate areas. The main damage caused by the infestation of this species is the reduction or deformation of young leaves, buds, fruits and flowers. When P. latus feeds on young papaya leaves, these present chlorosis and down curled distorted areas. In Mexico, the damage caused by this mite is called "monkey´s hand" because the area of the young papaya leaves is reduced leaving only the veins visible. This damage is similar to the symptoms caused by the infection of Papaya ringspot virus-p (PRSV-p). As P. latus and PRSV-p may cause similar damage to papaya leaves, the aim of this investigation was to determine the effect of P. latus, PRSV-p and their possible interaction in the reduction of foliar area. The diagnosis of PRSV-p was done by RT-PCR. The results showed that the effect produced by P. latus and PRSV-p were similar; however, the mites were found only on the younger leaves. As a result, the damage was observed only on these leaves, the chlorosis produced by the mites started in the central vein towards the end of the leaves; on the contrary, the damage of the virus can be found in any part of the leaves. The height and diameter of the stems in the plants were affected only by the infestation of the mites, as no difference was found on plants inoculated with PRSV-p.

El stress oxidativo ha sido reportado en la fisiopatoigenia de numerosas patologías de la mucosa oral. Se hace una actualización de estos mecanismos y se postula considerar en el tratamiento de estas patologías, la eliminación de todos los factores locales que puedan actuar mediante la inflamación tisular y el uso de antioxidantes, al menos como coadyuvantes de las terapias. Oxidative stress has been reported involucrated in many oral pathologies. We review these mechanisms and propose the elimination of all local factors implicated in the production of inflammation and the use of antioxidants in therapy. Fil: Rivarola de Gutiérrez, E. M.. Hospital Luis Lagomaggiore (Mendoza, Argentina). Servicio de Dermatología