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SUMMARY The main constraints on Third World energy development are the high price of imported oil, shrinking resources of fuel wood, lack of financial resources and inadequate technical and management capacity. There is an urgent need for financial and technical assistance, particularly to provide 'software'. This would be best provided by a specialist agency.RESUMEN Qbjetivos y medidas para la cooperación energética y mineraLas mayores restricciones en el desarrollo energético del Tercer Mundo, residen en el alto precio del petróleo importado, la reducción de los recursos de leña, la falta de recursos financieros y la inadecuada capacidad técnica y administrativa. Existe urgente necesidad de asistencia técnica y financiera, especialmente de 'programas', los que serían mejor provistos por agencias especializadas.RÉSUMÉ Objectéfs et Mesures pour une Coopération de l'Energie et des MinérauxLes principales restrictions au développement de l'énergie du Tiers‐Monde sont le prix élevé du pétrole importé, une diminution des ressources de bois‐combustible, un manque de ressources financières et une capacité technique et gestionnaire inadéquate. Il y a un besoin urgent d'une aide financière et technique, particulièrement dans l'implantation du 'logiciel'. Un organisme spécialisé serait le mieux placé à cette fin.

Context. The galactic cluster Westerlund 1 contains a rich population of evolved, massive stars. A high binary fraction has been inferred from previous multi-wavelength observations. Aims. We use multi-epoch spectroscopy of a large sample of early-type stars in Westerlund 1 to identify new binaries and binary candidates in the cluster. Methods. VLT/FLAMES was used with the GIRAFFE spectrograph in HR21 mode to obtain spectra of ∼100 OB stars over a 14-month baseline in 2008 and 2009, supplemented with follow-up observations in 2011 and 2013. Radial velocities were obtained from strong Paschen series absorption lines in the I-band. Results. We identify 20 new OB I–III binaries, a WN9h binary, and a WC9d binary, greatly increasing the number of directly confirmed binary systems in Westerlund 1, while 12 O9−9.5 Iab−III stars are identified as candidate binaries based on radial velocity changes that are inconsistent with photospheric variability. The 173.9 day SB1 W1030 represents the first longer-period system identified in the cluster, while the determination of a 53.95 day period for W44 (WR L) makes it the first Wolf-Rayet binary in Westerlund 1 with a confirmed orbital period greater than ten days. Our results suggest the binary fraction in the OB population is at least ∼40%, and may be significantly higher. Conclusions. These results demonstrate that binary systems can be effectively identified in the population of OB I−III stars evolving off the main sequence in Westerlund 1. Future multi-epoch surveys will be able to fully characterise this population. ; This research is partially supported by the Spanish Government Ministerio de Ciencia, Innovación y Universidades under grant PGC2018-093741-B-C21 (MICIU/AEI/FEDER, UE). I.N. is also supported by the Generalitat Valenciana through grant PROMETEO/2019/041. F.N. acknowledges financial support through Spanish grant PID2019-105552RB-C41 (MINECO/MCIU/AEI/FEDER) and from the Spanish State Research Agency (AEI) through the Unidad de Excelencia "María de ...

Context. Recent observational studies indicate that a large number of OB stars are found within binary systems which may be expected to interact during their lifetimes. Significant mass transfer or indeed merger of both components is expected to modify evolutionary pathways, facilitating the production of exceptionally massive stars which will present as blue stragglers. Identification and characterisation of such objects is crucial if the efficiency of mass transfer is to be established; a critical parameter in determining the outcomes of binary evolutionary channels. Aims. The young and coeval massive cluster Westerlund 1 hosts a rich population of X-ray bright OB and Wolf–Rayet stars where the emission is attributed to shocks in the wind collision zones of massive binaries. Motivated by this, we instigated a study of the extremely X-ray luminous O supergiants Wd1-27 and -30a. Methods. We subjected a multi-wavelength and -epoch photometric and spectroscopic dataset to quantitative non-LTE model atmosphere and time-series analysis in order to determine fundamental stellar parameters and search for evidence of binarity. A detailed examination of the second Gaia data release was undertaken to establish cluster membership. Results. Both stars were found to be early/mid-O hypergiants with luminosities, temperatures and masses significantly in excess of other early stars within Wd1, hence qualifying as massive blue stragglers. The binary nature of Wd1-27 remains uncertain but the detection of radial velocity changes and the X-ray properties of Wd1-30a suggest that it is a binary with an orbital period ≤10 days. Analysis of Gaia proper motion and parallactic data indicates that both stars are cluster members; we also provide a membership list for Wd1 based on this analysis. Conclusions. The presence of hypergiants of spectral types O to M within Wd1 cannot be understood solely via single-star evolution. We suppose that the early-B and mid-O hypergiants formed via binary-induced mass-stripping of the primary and mass-transfer to the secondary, respectively. This implies that for a subset of objects massive star-formation may be regarded as a two-stage process, with binary-driven mass-transfer or merger yielding stars with masses significantly in excess of their initial "birth" mass. ; This research was supported by the UK Science and Technology Facilities Council and the Spanish Government Ministerio de Economía y Competitivad (MINECO/FEDER) under grants AYA2015-68012-C2-2-P (Negueruela) and ESP2015-65597-C4-1-R and ESP2017-86582-C4-1-R (Najarro).

11 pages, 5 figures, 1 table ; Little is known about the antiviral response in mollusks. As in other invertebrates, the interferon signaling pathways have not been identified, and in fact, there is a debate about whether invertebrates possess antiviral immunity similar to that of vertebrates. In marine bivalves, due to their filtering activity, interaction with putative pathogens, including viruses, is very high, suggesting that they should have mechanisms to address these infections. In this study, we confirmed that constitutively expressed molecules in naive mussels confer resistance in oysters to ostreid herpesvirus 1 (OsHV-1) when oyster hemocytes are incubated with mussel hemolymph. Using a proteomic approach, myticin C peptides were identified in both mussel hemolymph and hemocytes. Myticins, antimicrobial peptides that have been previously characterized, were constitutively expressed in a fraction of mussel hemocytes and showed antiviral activity against OsHV-1, suggesting that these molecules could be responsible for the antiviral activity of mussel hemolymph. For the first time, a molecule from a bivalve has shown antiviral activity against a virus affecting mollusks. Moreover, myticin C peptides showed antiviral activity against human herpes simplex viruses 1 (HSV-1) and 2 (HSV-2). In summary, our work sheds light on the invertebrate antiviral immune response with the identification of a molecule with potential biotechnological applications ; This work was partially funded by project AGL2015-65705-R from the Ministerio de Economía y Competitividad, CSIC Intramural 201640E024, and EU Project BIVALIFE (266157). Financial support given to Rebeca Moreira and Patricia Pereiro by the Spanish Government (BES-2009-029765 and AP2010-2408, respectively) is acknowledged. Francisco Parra's laboratory was supported by grant GRUPIN14-099 from Principado de Asturias (Spain). Ángel L. Álvarez is a postdoctoral fellow in F. Parra's laboratory, partially funded by Ayuntamiento de Ribera de Arriba/La Ribera (Asturias, Spain) ; Peer reviewed

Massive stars play an important role in both cluster and galactic evolution and the rate at which they lose mass is a key driver of both their own evolution and their interaction with the environment up to and including their terminal SNe explosions. Young massive clusters provide an ideal opportunity to study a co-eval population of massive stars, where both their individual properties and the interaction with their environment can be studied in detail. We aim to study the constituent stars of the Galactic cluster Westerlund 1 in order to determine mass-loss rates for the diverse post-main sequence population of massive stars. To accomplish this we made 3mm continuum observations with the Atacama Large Millimetre/submillimetre Array. We detected emission from 50 stars in Westerlund 1, comprising all 21 Wolf-Rayets within the field of view, plus eight cool and 21 OB super-/hypergiants. Emission nebulae were associated with a number of the cool hypergiants while, unexpectedly, a number of hot stars also appear spatially resolved. We were able to measure the mass-loss rates for a unique population of massive post-main sequence stars at every stage of evolution, confirming a significant increase as stars transitioned from OB supergiant to WR states via LBV and/or cool hypergiant phases. Fortuitously, the range of spectral types exhibited by the OB supergiants provides a critical test of radiatively-driven wind theory and in particular the reality of the bi-stability jump. The extreme mass-loss rate inferred for the interacting binary Wd1-9 in comparison to other cluster members confirmed the key role binarity plays in massive stellar evolution. The presence of compact nebulae around a number of OB and WR stars is unexpected; by analogy to the cool super-/hypergiants we attribute this to confinement and sculpting of the stellar wind via interaction with the intra-cluster medium/wind. Given the morphologies of core collapse SNe depend on the nature of the pre-explosion circumstellar environment, if this hypothesis is correct then the properties of the explosion depend not just on the progenitor, but also the environment in which it is located. ; D. Fenech wishes to acknowledge funding from a STFC consolidated grant (ST/M001334/1). IN is partially supported by the Spanish Government Ministerio de Economía y Competitivad (MINECO/FEDER) under grant AYA2015-68012-C2-2-P.

The presence of massive stars (MSs) in the region close to the Galactic Centre (GC) poses several questions about their origin. The harsh environment of the GC favours specific formation scenarios, each of which should imprint characteristic kinematic features on the MSs. We present a 2D kinematic analysis of MSs in a GC region surrounding Sgr A* based on high-precision proper motions obtained with the Hubble Space Telescope. Thanks to a careful data reduction, well-measured bright stars in our proper-motion catalogues have errors better than 0.5 mas yr−1. We discuss the absolute motion of the MSs in the field and their motion relative to Sgr A*, the Arches, and the Quintuplet. For the majority of the MSs, we rule out any distance further than 3–4 kpc from Sgr A* using only kinematic arguments. If their membership to the GC is confirmed, most of the isolated MSs are likely not associated with either the Arches or Quintuplet clusters or Sgr A*. Only a few MSs have proper motions, suggesting that they are likely members of the Arches cluster, in agreement with previous spectroscopic results. Line-of-sight radial velocities and distances are required to shed further light on the origin of most of these massive objects. We also present an analysis of other fast-moving objects in the GC region, finding no clear excess of high-velocity escaping stars. We make our astro-photometric catalogues publicly available. ; ML and AB acknowledge support from STScI grants GO 12915 and 13771. DJL acknowledges support from the Spanish Government Ministerio de Ciencia, Innovación y Universidades through grants PGC-2018-091 3741-B-C22 and from the Canarian Agency for Research, Innovation and Information Society (ACIISI), of the Canary Islands Government, and the European Regional Development Fund (ERDF), under grant with reference ProID2017010115. LRP acknowledges support from the Generalitat Valenciana through the grant PROMETEO/2019/041. LRB acknowledges partial support by MIUR under PRIN programme no. 2017Z2HSMF.

LA VIDA ME DIO OTRA OPORTUNIDAD no es solo el recuento de historias de dolor, es también la mirada sincera y optimista de quienes anhelan cambiar su propia historia, enmendar sus errores e imprimirle esperanza a sus vidas. Fruto del trabajo mancomunado de grupos interdisciplinarios de la Armada Nacional y la Universidad Santo Tomás, esta obra estudia el contexto social, político y militar de la historia que vivió la región de los Montes de María como consecuencia del conflicto. Es, además, un aporte institucional al Sistema Integral de Verdad, Justicia, Reparación y No Repetición como parte del compromiso que tenemos con las nuevas generaciones de continuar con la construcción de la memoria y el tejido social para contribuir a restaurar la paz y alcanzar la reconciliación.

2MASS J20395358+4222505 is an obscured early B supergiant near the massive OB star association Cygnus OB2. Despite its bright infrared magnitude (Ks = 5.82) it has remained largely ignored because of its dim optical magnitude (B = 16.63, V = 13.68). In a previous paper, we classified it as a highly reddened, potentially extremely luminous, early B-type supergiant. We obtained its spectrum in the U, B and R spectral bands during commissioning observations with the instrument MEGARA at the Gran Telescopio CANARIAS. It displays a particularly strong Hα emission for its spectral type, B1 Ia. The star seems to be in an intermediate phase between supergiant and hypergiant, a group that it will probably join in the near (astronomical) future. We observe a radial velocity difference between individual observations and determine the stellar parameters, obtaining Teff = 24 000 K and log gc = 2.88 ± 0.15. The rotational velocity found is large for a B supergiant, v sin i = 110 ± 25 kms−1. The abundance pattern is consistent with solar, with a mild C underabundance (based on a single line). Assuming that J20395358+4222505 is at the distance of Cyg OB2, we derive the radius from infrared photometry, finding R = 41.2 ± 4.0 R⊙, log(L/L⊙) = 5.71 ± 0.04 and a spectroscopic mass of 46.5 ± 15.0 M⊙. The clumped mass-loss rate (clumping factor 10) is very high for the spectral type, M˙ = 2.4 × 10−6 M⊙ a−1. The high rotational velocity and mass-loss rate place the star at the hot side of the bi-stability jump. Together with the nearly solar CNO abundance pattern, they may also point to evolution in a binary system, J20395358+4222505 being the initial secondary. ; SS-D and AH acknowledge support from the Spanish Government Ministerio de Ciencia e Innovación through grants PGC-2018-091 3741-B-C22 and CEX2019-000920-S and from the Canarian Agency for Research, Innovation and Information Society (ACIISI), of the Canary Islands Government, and the European Regional Development Fund (ERDF), under grant with reference ProID2020010016. MG and FN acknowledge financial support through Spanish grant PID2019-105552RB-C41 (MINECO/MCIU/AEI/FEDER) and from the Spanish State Research Agency (AEI) through the Unidad de Excelencia 'María de Maeztu'-Centro de Astrobiología (CSIC-INTA) project No. MDM-2017-0737. SRB acknowledges support by the Spanish Government under grants AYA2015-68012-C2-2-P and PGC2018-093741-B-C21/C22 (MICIU/AEI/FEDER, UE). SRA acknowledges funding support from the FONDECYT Iniciación project 11171025 and the FONDECYT Regular project 1201490. JIP acknowledges finantial support from projects Estallidos6 AYA2016-79724-C4 (Spanish Ministerio de Economia y Competitividad), Estallidos7 PID2019-107408GB-C44 (Spanish Ministerio de Ciencia e Innovacion), grant P18-FR-2664 (Junta de Andalucía), and grant SEV-2017-0709 'Centro de Excelencia Severo Ochoa Program' (Spanish Science Ministry). AGP, SP, AG-M, JG and NC acknowledge support from the Spanish MCI through project RTI2018-096188-B-I00.

Cosmic history has witnessed the lives and deaths of multiple generations of massive stars, all of them invigorating their host galaxies with ionizing photons, kinetic energy, fresh material, and stellar-mass black holes. Ubiquitous engines as they are, astrophysics needs a good understanding of their formation, evolution, properties and yields throughout the history of the Universe, and with decreasing metal content mimicking the environment at the earliest epochs. Ultimately, a physical model that could be extrapolated to zero metallicity would enable tackling long-standing questions such as "What did the first, very massive stars of the Universe look like?" or "What was their role in the re-ionization of the Universe?" Yet, most of our knowledge of metal-poor massive stars is drawn from one single point in metallicity. Massive stars in the Small Magellanic Cloud (SMC, ∼1/5Z⊙ ) currently serve as templates for low-metallicity objects in the early Universe, even though significant differences with respect to massive stars with poorer metal content have been reported. This White Paper summarizes the current knowledge on extremely (sub-SMC) metal poor massive stars, highlighting the most outstanding open questions and the need to supersede the SMC as standard. A new paradigm can be built from nearby extremely metal-poor galaxies that make a new metallicity ladder, but massive stars in these galaxies are out of reach to current observational facilities. Such a task would require an L-size mission, consisting of a 10m-class space telescope operating in the optical and the ultraviolet ranges. Alternatively, we propose that ESA unites efforts with NASA to make the LUVOIR mission concept a reality, thus continuing the successful partnership that made the Hubble Space Telescope one of the greatest observatories of all time. ; Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. MG and FN acknowledge financial support through Spanish grants ESP2017-86582-C4-1-R and PID2019-105552RB-C41 (MCIU/AEI/FEDER) and from the Spanish State Research Agency (AEI) through the Unidad de Excelencia "María de Maeztu" – Centro de Astrobiología (CSIC-INTA) project number MDM-2017-0737. AH acknowledges support by grants PGC-2018-091 3741-B-C22 and SEV 2015-0548, and by the Canarian Agency for Research, Innovation and Information Society (ACIISI), of the Canary Islands Government, and the European Regional Development Fund (ERDF), under grant ProID2017010115. SdM acknowledges the Netherlands Organisation for Scientific Research (Vidi grant BinWaves 639.042.728). D.Sz. has been supported by the Alexander von Humboldt Foundation.