The very faint hard state of the persistent neutron star X-ray binary SLX 1737-282 near the Galactic centre

We report on a detailed study of the spectral and temporal properties of the neutron star low mass X-ray binary SLX 1737-282, which is located only ~1degr away from Sgr A. The system is expected to have a short orbital period, even within the ultra-compact regime, given its persistent nature at low X-ray luminosities and the long duration thermonuclear burst that it has displayed. We have analysed a Suzaku (18 ks) observation and an XMM-Newton (39 ks) observation taken 7 years apart. We infer (0.5-10 keV) X-ray luminosities in the range 3-6 x10^35erg s-1, in agreement with previous findings. The spectra are well described by a relatively cool (kTbb = 0.5 keV) black body component plus a Comptonized emission component with {\Gamma} ~1.5-1.7. These values are consistent with the source being in a faint hard state, as confirmed by the ~ 20 per cent fractional root mean square amplitude of the fast variability (0.1 - 7 Hz) inferred from the XMM-Newton data. The electron temperature of the corona is >7 keV for the Suzaku observation, but it is measured to be as low as ~2 keV in the XMM-Newton data at higher flux. The latter is significantly lower than expected for systems in the hard state. We searched for X-ray pulsations and imposed an upper limit to their semi-amplitude of 2 per cent (0.001 - 7 Hz). Finally, we investigated the origin of the low frequency variability emission present in the XMM-Newton data and ruled out an absorption dip origin. This constraint the orbital inclination of the system to 65 degr unless the orbital period is longer than 11 hr (i.e. the length of the XMM-Newton observation).Comment: 7 pages, 4 figures, 1 table. Accepted for publication in MNRA

Theoretical inspection of the spin-crossover [Fe(tzpy)2(NCS)2] complex on Au(100) surface

We explore the deposition of the spin-crossover [Fe(tzpy)2(NCS)2] complex on the Au(100) surface by means of density functional theory (DFT) based calculations. Two different routes have been employed: low-cost finite cluster-based calculations, where both the Fe complex and the surface are maintained fixed while the molecule approaches the surface; and periodic DFT plane-wave calculations, where the surface is represented by a four-layer slab and both the molecule and surface are relaxed. Our results show that the bridge adsorption site is preferred over the on-top and fourfold hollow ones for both spin states, although they are energetically close. The LS molecule is stabilized by the surface, and the HS-LS energy difference is enhanced by about 15%-25% once deposited. The different Fe ligand field for LS and HS molecules manifests on the composition and energy of the low-lying bands. Our simulated STM images indicate that it is possible to distinguish the spin state of the deposited molecules by tuning the bias voltage of the STM tip. Finally, it should be noted that the use of a reduced size cluster to simulate the Au(100) surface proves to be a low-cost and reliable strategy, providing results in good agreement with those resulting from state-of-the-art periodic calculations for this system.Ministerio de Ciencia e Innovación PGC2018- 101689-B-I0

The optical counterpart of the bright X-ray transient Swift J1745-26

We present a 30-day monitoring campaign of the optical counterpart of the bright X-ray transient Swift J1745-26, starting only 19 minutes after the discovery of the source. We observe the system peaking at i' ~17.6 on day 6 (MJD 56192) to then decay at a rate of ~0.04 mag/day. We show that the optical peak occurs at least 3 days later than the hard X-ray (15-50 keV) flux peak. Our measurements result in an outburst amplitude greater than 4.3 magnitudes, which favours an orbital period < 21 h and a companion star with a spectral type later than ~ A0. Spectroscopic observations taken with the GTC-10.4 m telescope reveal a broad (FWHM ~ 1100 km/s), double-peaked H_alpha emission line from which we constrain the radial velocity semi-amplitude of the donor to be K_2 > 250 km/s. The breadth of the line and the observed optical and X-ray fluxes suggest that Swift J1745-26 is a new black hole candidate located closer than ~7 kpc.Comment: 5 pages, 4 figures, accepted for publication in MNRA

De espadas y de cañas: esgrima y astrología en las jácaras de Quevedo

This article takes up the matter of classifying Quevedo’s jácaras. Two criteria are proposed: one that follows the narrative structure and a second that deals with the predominant themes. In addition, the article studies questions of fencing and astrology in these works. These two disciplines are used by Quevedo to underline his own style of writing jácaras, one that is based on the dissonance between the popular and the learned. This contrast serves to transgress the principle of decorum in the themes utilized. Finally, the essay analyses the possible social and political implications that may emerge from the uses of fencing and astrology in the genre of the jácaras.El presente artículo aborda el problema de la clasificación de las jácaras de Quevedo. Se proponen dos criterios de clasificación: uno según su estructura narrativa y otro según los temas predominantes. En concreto, se estudian los temas de la esgrima y la astrología en dicho corpus. Con estas disciplinas, Quevedo enfatiza el rasgo característico de su estilo personal de hacer jácaras: la disonancia entre los ámbitos culto y popular. Dicho contraste se basa en la transgresión del principio del decoro en el plano temático. Por último, se analizan las posibles implicaciones políticas y sociales que resultan de la inserción de la esgrima y la astrología en el universo literario de la jácara

TPEA PROJECT: MARITIME SPATIAL PLANNING IN THE GULF OF CADIZ

Maritime Spatial Planning (MSP) is coming to prominence as a new approach to the governance of the seas and oceans. It is taking on international importance as maritime nations exert greater control over their territorial waters and, in many cases, over much more extensive exclusive economic zones (Jay, 2010; Schaefer & Barale, 2011). This is in the interests of reversing the environmental degradation of the seas and facilitating the sustainable use of marine resources, both for traditional uses, such as fishing and navigation, and newer uses, such as renewable energy and mariculture (Douvere, 2008). MSP is being encouraged worldwide by inter-governmental bodies, NGOs, stakeholder organisations and marine scientists and managers (Agardy, 2010; De Santo, 2011; HELCOM & OSPAR, 2003), and a growing number of nations are drawing up spatial plans to regulate the use of their marine territories, in a way analogous to land-use planning

Marine knowledge as a basis for Maritime Spatial Planning: TPEA Project

Comunicación oral presentada en SIEBM XVIII Simposio Ibérico de Biología MarinaThe Transboundary Planning in the European Atlantic (TPEA) project is developing as response to the European Commission (DG Mare’s) call for a Project on Maritime Spatial Planning in the Atlantic, including Celtic Sea and Bay of Biscay, in order to reflect the aim of the project, which is to deliver a commonly-agreed approach to cross-border MSP in the European Atlantic region.DG MARE - E

El vocero, un imperativo de la comunicación institucional en Cuba

La figura del vocero institucional presencial constituye una necesidad ante la batalla sin precedentes que libra la Revolución Cubana en el plano político-comunicacional. Su implementación perfeccionaría la articulación de todos nuestros Organismos de la Administración Central del Estado (OACE), instituciones y organizaciones principales, así como los gobiernos territoriales, y sus estrategias comunicacionales, hacia los diferentes públicos, tanto internos como externos. Ello conduciría al cumplimiento efectivo y eficaz de la Estrategia de Comunicación País, y estaría en correspondencia con la práctica internacional

El vocero, un imperativo de la comunicación institucional en Cuba

The figure of the face-to-face institutional spokesperson constitutes a necessity that adjusts to the current conditions in which the Cuban Revolution is being fought, an unprecedented battle in the political-communicational sphere. Its implementation would improve the articulation of all our OACEs, main institutions and organizations, as well as the territorial governments, and their communication strategies, towards the different publics, including the internal public (the Cuban population) and external publics (which include foreign audiences and Cubans residing abroad). This would lead to effective and efficient compliance with the Country Communication Strategy, and would be in line with international practice.La figura del vocero institucional presencial constituye una necesidad ante la batalla sin precedentes que libra la Revolución Cubana en el plano político-comunicacional. Su implementación perfeccionaría la articulación de todos nuestros Organismos de la Administración Central del Estado (OACE), instituciones y organizaciones principales, así como los gobiernos territoriales, y sus estrategias comunicacionales, hacia los diferentes públicos, tanto internos como externos. Ello conduciría al cumplimiento efectivo y eficaz de la Estrategia de Comunicación País, y estaría en correspondencia con la práctica internacional