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Intense autumnal coastal biogenic particle settling fluxes align with phytoplankton phenology changes off the western Antarctic Peninsula
No full text14 pages, 7 figures, 2 tables, supplementary material https://doi.org/10.1038/s41598-025-92914-9.-- Data availability: All data, code, and materials used in the analyses are available in the figures, tables and supplementary information presented in the articleAutumnal settling particle fluxes were studied in the Antarctic coastal zone. The study revealed that the particulate organic carbon (POC) flux exported from the euphotic zone towards the seabed equals the magnitude of the summer pulse when typically, > 95% of the Antarctic annual flux develops. The pelagic POC flux was accompanied with centric and pennate diatoms and euphausiid faecal pellets, which together comprised most of the biogenic particles (and biogenic silica) collected in the sediment trap used in the Gerlache Strait. Our results strongly suggest that the most important drivers of the unusual seasonal extension observed for the settling particle export were increasing glacier melting and an extended productive period. The present study may provide a baseline for Antarctic coastal biogenic particle flux studies and shows that ongoing environmental warming makes the autumnal biogenic settling particle production near shore more intense than typically observed off shoreThis work represents a contribution to CSIC HUBs Geociencias and PolarCSIC and acknowledges grant CEX2019-000928-S funded by AEI 10.13039/50110001103. Open Access funding provided thanks to the CRUE-CSIC agreement with Springer NaturePeer reviewe
Sistemas de Gestión de Pesquerías Comerciales: desde la recolección de datos a su visualización Web
No full textXV Reunión del Foro Científico sobre la pesca española en el Mediterráneo, 17 y 18 de septiembre de 2024, Cartagena.-- 8 pages, 7 figuresLa sostenibilidad de las pesquerías debe lograrse considerando aspectos biológicos, ambientales, sociales y económicos. Para ello, se deben seguir diferentes estrategias, incluyendo la cogestión, que fomenta que científificos, Gobiernos, pescadores y la sociedad civil gestionen conjuntamente los recursos oceánicos. [...]With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)Peer reviewe
Redistribution of particles across the nucleus of comet 67P/Churyumov-Gerasimenko
No full textThomas, N. et al.--Full list of authors: Thomas, N.; Davidsson, B.; El-Maarry, M. R.; Fornasier, S.; Giacomini, L.; Gracia-Berná, A. G.; Hviid, S. F.; Ip, W. -H.; Jorda, L.; Keller, H. U.; Knollenberg, J.; Kührt, E.; La Forgia, F.; Lai, I. L.; Liao, Y.; Marschall, R.; Massironi, M.; Mottola, S.; Pajola, M.; Poch, O.; Pommerol, A.; Preusker, F.; Scholten, F.; Su, C. C.; Wu, J. S.; Vincent, J. -B.; Sierks, H.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; A'Hearn, M. F.; Barucci, M. A.; Bertaux, J. -L.; Bertini, I.; Cremonese, G.; Da Deppo, V.; Debei, S.; de Cecco, M.; Fulle, M.; Groussin, O.; Gutierrez, P. J.; Kramm, J. -R.; Küppers, M.; Lara, L. M.; Lazzarin, M.; Lopez Moreno, J. J.; Marzari, F.; Michalik, H.; Naletto, G.; Agarwal, J.; Güttler, C.; Oklay, N.; Tubiana, C.Context. We present an investigation of the surface properties of areas on the nucleus of comet 67P/Churyumov-Gerasimenko. Aims. We aim to show that transport of material from one part of the cometary nucleus to another is a significant mechanism that influences the appearance of the nucleus and the surface thermal properties. Methods. We used data from the OSIRIS imaging system onboard the Rosetta spacecraft to identify surface features on the nucleus that can be produced by various transport mechanisms. We used simple calculations based on previous works to establish the plausibility of dust transport from one part of the nucleus to another. Results. We show by observation and modeling that "airfall" as a consequence of non-escaping large particles emitted from the neck region of the nucleus is a plausible explanation for the smooth thin deposits in the northern hemisphere of the nucleus. The consequences are also discussed. We also present observations of aeolian ripples and ventifacts. We show by numerical modeling that a type of saltation is plausible even under the rarified gas densities seen at the surface of the nucleus. However, interparticle cohesive forces present difficulties for this model, and an alternative mechanism for the initiation of reptation and creep may result from the airfall mechanism. The requirements on gas density and other parameters of this alternative make it a more attractive explanation for the observations. The uncertainties and implications are discussed. © ESO, 2015.OSIRIS was built by a consortium of the Max-Planck-Institut für Sonnensystemforschung, in Göttingen, Germany, CISAS-University of Padova, Italy, the Laboratoire d’Astrophysique de Marseille, France, the Instituto de Astrofisica de Andalucia, CSIC, Granada, Spain, the Research and Scientific Support Department of the European Space Agency, Noordwijk, The Netherlands, the Instituto Nacional de Tecnica Aeroespacial, Madrid, Spain, the Universidad Politechnica de Madrid, Spain, the Department of Physics and Astronomy of Uppsala University, Sweden, and the Institut für Datentechnik und Kommunikationsnetze der Technischen Universität Braunschweig, Germany. The support of the national funding agencies of Germany (DLR), France (CNES), Italy (ASI), Spain (MEC), Sweden (SNSB), and the ESA Technical Directorate is gratefully acknowledged. The team from the University of Bern is supported through the Swiss National Science Foundation (grant No. 200020_152560) and through NCCR PlanetS
Óxidos mixtos de rutenio como electrocatalizadores para la reacción de evolución de oxígeno en medio ácido
No full textTesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Química Física Aplicada. Fecha de Lectura: 25-10-2024La creciente demanda energética y los efectos ambientales del uso de combustibles fósiles hacen urgente la transición hacia fuentes renovables. El hidrógeno verde, producido mediante electrólisis del agua usando energía renovable, se presenta como una solución clave para almacenar energía y descarbonizar sectores industriales difíciles de electrificar. En la electrólisis, la eficiencia está limitada por la Reacción de Evolución de Oxígeno (OER), que requiere catalizadores eficaces y estables. Actualmente, los electrolizadores PEMWE son los más prometedores, aunque dependen de materiales escasos como el iridio.
La tesis se centra en el desarrollo de catalizadores basados en óxidos mixtos de rutenio para mejorar la OER en medio ácido, dado que el Ru es más activo y más económico que el Ir, aunque menos estable. Se estudian diferentes estructuras cristalinas (perovskitas simples y dobles, pirocloros, estructuras AB₂O₅), evaluando cómo influyen el estado de oxidación del Ru, la presencia de otros cationes, y la geometría del material en su actividad y durabilidad. Los catalizadores más prometedores presentan alta simetría, enlaces cortos Ru–O y Ru–Ru, y un estado de oxidación elevado (Ru>4+).
Los trabajos experimentales han generado tres publicaciones científicas relevantes, destacando el diseño de catalizadores estables y activos como Sr₁₋ₓKₓRuO₃, Dy₂NiRuO₆, y NdMn₁.₅Ru₀.₅O₅, este último con buen rendimiento también en condiciones reales de electrólisis en PEMWE y mostrando bifuncionalidad para OER y ORR en medio ácido.Peer reviewe
Examination of the change in H/V spectral ratio values before and after the February 6, 2023, Türkiye earthquakes: The case study of Iskenderun city
No full textThe Eastern Anatolian Fault Zone (EAFZ) is a prominent active tectonic feature within the Alpine-Himalayan belt,
hosting significant faults in the Anatolia region linked to major historical earthquakes. On February 6, 2023, the
EAFZ experienced two major earthquakes (Mw 7.7 and Mw 7.6) resulting in extensive destruction and loss of life and
property. This study investigates the nuanced variations in the H/V spectral ratios before and after these seismic
events. With such a purpose we used earthquake data of varying magnitudes occurring pre- and post-February 6,
2023, recorded by 8 strong ground motion stations in Iskenderun city. A total of 80 earthquakes were analyzed, 10
per station (5 pre- and 5 post-event). The spectral ratios for each earthquake were computed following the
standardised HVSR method. Results highlight significant changes, particularly in station 3112 on the Iskenderun
coast, while other stations exhibited minimal alterations in dominant frequency and HVSR curve shapes. Although
stations 3116 and 3119 showed changes in dominant frequencies, the averaged curve shape remained consistent.
Following same procedure, future assessments are expected for various cities and locations, expanding the dataset
for comprehensive evaluations on loss distribution patterns
Tectonic evolution of the Atlantic rift, central sector offshore Uruguay
No full textThe Uruguayan Continental Margin (UCM) is considered one of the most promising frontier areas for hydrocarbon exploration in the South Atlantic. The UCM central sector, corresponding to the transitional region between the Punta del Este and Pelotas basins and where the Rio de la Plata Transfer System (RPTS) is located, exhibits outstanding characteristics such as interruption of the seaward dipping reflectors (SDRs), dislocation of magnetic and gravity anomalies and depocenters, and hyper-thinning of the continental crust. Owing to these characteristics, this sector is a key area for understanding the evolution of the margin during the Atlantic opening and evaluating the real potential of the UCM to contain hydrocarbon accumulations. This study demonstrates the results of a new subsurface mapping method using 2D and 3D seismic data in the central sector of the UCM. Structural interpretations have led to the definition of i) a NW-oriented hyperextended region located where the SDRs are interrupted, characterized by a shallow Moho (˂3 km); ii) a set of NW-SE oriented transtensional faults, some of which reach the Moho, which has delineated a series of discrete grabens; and iii) a Barremian-Aptian depocenter with a rhomboidal geometry, exhibiting the greatest thickness over the hyperextended crust region. The central sector of the UCM concentrates on the extensional processes associated with the breakup of Western Gondwana, which controlled the initial phase of the Atlantic opening in this region. The sinistral transcurrent nature of the RPTS plays a crucial role in generating the transtensional stress field in an extensive regional context. This process reactivates basement-inherited structures with a general NW-SE orientation, leading to the formation of subsidence areas. The proposed new tectonic model will contribute to the knowledge of the hydrocarbon potential of the UCM.This study contributes to the framework of the Agencia Nacional de Investigación e Innovación (ANII) Project FCE_1_2021_1_166362
Hexosome dispersions with diglycerol based surfactants as lipophilic drug delivery vehicles
No full textUsing time series studies to unravel the short-term health effects of particulate matter air pollution in Eastern Mediterranean Region
No full textPeer reviewe
Martian Highlands Differentiation Concomitant to Dichotomy Formation
No full textThis is InSight contribution 349.-- 31 pages, 9 figures, 4 tables.-- Data Availability Statement: The source code (C++) used to produce the data is available in Bonnet Gibet (2024a). Figures can be fully reproduced using the post-processing codes and data referenced in Bonnet Gibet (2024b)The Martian surface composition appears mainly mafic but recent observations have revealed the presence of differentiated rocks, only in the highlands. Here, we demonstrate that differentiated melts can form during the construction of thick crustal regions on Mars by fractional crystallisation of a mafic magma, without plate tectonics. On a stagnant-lid planet, regions of thicker crusts contain more heat-producing elements and are associated to thinner lithospheres and to higher mantle melt fractions. This induces larger crustal extraction rates where the crust is thicker. This positive feedback mechanism is favored at large wavelengths and can explain the formation of the Martian dichotomy. We further develop an asymmetric parameterized thermal evolution model accounting for crustal extraction, where the well-mixed convective mantle is topped by two lithospheres (north/south) characterized by specific thermal and crustal structures. We use this model in a Bayesian inversion to investigate the conditions that allow crustal temperatures to be maintained above the basalt solidus during crustal growth, resulting in the formation of evolved melts. Among the thermal evolution models matching constraints on the structure of the Martian crust and mantle provided by the InSight NASA mission, a non-negligible fraction allows partial melting and differentiation of the crust in the south, which can occur very early (100 Myr) as well as during the Hesperian; partial melting in the north appears unlikely. Although crustal differentiation may occur on a hemispheric scale on Mars, its vertical extent would be limited to less than a third of the crustal thicknessThis project has received funding from the European Research Council under the European Union's Horizon 2020 research and innovation programme (Grant 101001689). CM acknowledges support from the Institut Universitaire de France. VBG and CM acknowledge the French Space Agency CNES and ANR (MAGIS ANR-19-CE31-0008-08) for funding the InSight Science analysisWith the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)Peer reviewe
Jetted subgalactic-size radio sources in merging galaxies: A jet redirection scenario
No full textContext. The long-standing question concerning jetted subgalactic-size (JSS) radio sources is whether they will evolve into large radio galaxies, die before escaping the host galaxy, or remain indefinitely confined to their compact size.Aims. Our main goal is to propose a scenario that explains the relative number of JSS radio sources and their general properties.Methods. We studied the parsec-scale radio morphology of a complete sample of 21 objects using Very Long Baseline Array (VLBA) observations at various frequencies and analyzed the morphological characteristics of their optical hosts.Results. Many of these radio sources exhibit radio morphologies consistent with transverse motions of their bright edges and are found in dynamically disturbed galaxies. VLBA images suggest the possible presence of large-angle, short-period precessing jets, and an orbital motion of the radio-loud active galactic nucleus (AGN) in a dual or binary system. The majority of JSS radio sources appear to be in systems in different stages of their merging evolution.Conclusions. We propose a scenario where rapid jet redirection, through precession or orbital motion, prevents the jet from penetrating the interstellar medium (ISM) sufficiently to escape the host galaxy. Most JSS radio sources remain compact due to their occurrence in merging galaxies.© The Authors 2025.We thank Luca Jerrert Rossi ([email protected]) for creating the drawings used in this paper. CO and SB acknowledge support from the Natural Sciences and Engineering Research Council (NSERC) of Canada. CSp acknowledges financial support from the Italian National Institute for Astrophysics (INAF) under the project “Collaborative research on VLBI as an ultimate test to ΛCDM model” (Ricerca Fondamentale 2022). MPT acknowledges financial support from the Severo Ochoa grant CEX2021-001131-S and from the Spanish grant PID2023-147883NB-C21, funded by MCIU/AEI/10.13039/501100011033, as well as support through ERDF/EU. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. This research has made use of the NASA/IPAC Extragalactic Database, which is funded by the National Aeronautics and Space Administration and operated by the California Institute of Technology. Based on observations made with the Nordic Optical Telescope, owned in collaboration by the University of Turku and Aarhus University, and operated jointly by Aarhus University, the University of Turku and the University of Oslo, representing Denmark, Finland and Norway, the University of Iceland and Stockholm University at the Observatorio del Roque de los Muchachos, La Palma, Spain, of the Instituto de Astrofisica de Canarias. The Pan-STARRS1 Surveys (PS1) and the PS1 public science archive have been made possible through contributions by the Institute for Astronomy, the University of Hawaii, the Pan-STARRS Project Office, the Max-Planck Society and its participating institutes, the Max Planck Institute for Astronomy, Heidelberg and the Max Planck Institute for Extraterrestrial Physics, Garching, The Johns Hopkins University, Durham University, the University of Edinburgh, the Queen’s University Belfast, the Harvard-Smithsonian Center for Astrophysics, the Las Cumbres Observatory Global Telescope Network Incorporated, the National Central University of Taiwan, the Space Telescope Science Institute, the National Aeronautics and Space Administration under Grant No. NNX08AR22G issued through the Planetary Science Division of the NASA Science Mission Directorate, the National Science Foundation Grant No. AST-1238877, the University of Maryland, Eotvos Lorand University (ELTE), the Los Alamos National Laboratory, and the Gordon and Betty Moore Foundation. Funding for the Sloan Digital Sky Survey V has been provided by the Alfred P. Sloan Foundation, the Heising-Simons Foundation, the National Science Foundation, and the Participating Institutions. SDSS acknowledges support and resources from the Center for High-Performance Computing at the University of Utah. SDSS telescopes are located at Apache Point Observatory, funded by the Astrophysical Research Consortium and operated by New Mexico State University, and at Las Campanas Observatory, operated by the Carnegie Institution for Science. The SDSS web site is www.sdss.org. SDSS is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS Collaboration, including Caltech, The Carnegie Institution for Science, Chilean National Time Allocation Committee (CNTAC) ratified researchers, The Flatiron Institute, the Gotham Participation Group, Harvard University, Heidelberg University, The Johns Hopkins University, L’Ecole polytechnique fédérale de Lausanne (EPFL), Leibniz-Institut für Astrophysik Potsdam (AIP), Max-Planck-Institut für Astronomie (MPIA Heidelberg), Max-Planck-Institut für Extraterrestrische Physik (MPE), Nanjing University, National Astronomical Observatories of China (NAOC), New Mexico State University, The Ohio State University, Pennsylvania State University, Smithsonian Astrophysical Observatory, Space Telescope Science Institute (STScI), the Stellar Astrophysics Participation Group, Universidad Nacional Autónoma de México, University of Arizona, University of Colorado Boulder, University of Illinois at Urbana-Champaign, University of Toronto, University of Utah, University of Virginia, Yale University, and Yunnan University.”With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2021-001131-S).Peer reviewe