16 research outputs found

    Revisiting constraints on WIMPs around primordial black holes

    Get PDF
    While Primordial Black Holes (PBHs) with masses MPBH1011MM_{\rm PBH} \gtrsim 10^{-11} \, M_\odot cannot comprise the entirety of dark matter, the existence of even a small population of these objects can have profound astrophysical consequences. A sub-dominant population of PBHs will efficiently accrete dark matter particles before matter-radiation equality, giving rise to high-density dark matter spikes. We consider here the scenario in which dark matter is comprised primarily of Weakly Interacting Massive Particles (WIMPs) with a small sub-dominant contribution coming from PBHs, and revisit the constraints on the annihilation of WIMPs in these spikes using observations of the isotropic gamma-ray background (IGRB) and the Cosmic Microwave Background (CMB), for a range of WIMP masses, annihilation channels, cross sections, and PBH mass functions. We find that the constraints derived using the IGRB have been significantly overestimated (in some cases by many orders of magnitude), and that limits obtained using observations of the CMB are typically stronger than, or comparable to, those coming from the IGRB. Importantly, we show that O(M)\sim \mathcal{O}(M_\odot) PBHs can still contribute significantly to the dark matter density for sufficiently low WIMP masses and p-wave annihilation cross sections.Comment: 15 pages, 6 figure

    Moluscos de hábitats bentónicos del volcán de fango Gazul (Golfo de Cádiz)

    Get PDF
    Molluscs from the Gazul mud volcano and its adjacent areas in the northern Gulf of Cádiz were studied using differ­ent sampling methods. This mud volcano has vulnerable deep-sea habitats and a potential high biodiversity. A total of 232 species were identified from the taxocoenosis and thanatocoenosis, of which 86 are new records for the Spanish margin of the Gulf of Cádiz, three of them are new records for Spanish waters and two species are new to science. The high species richness observed could be related to the combination of different sampling methods, the study of the thanatocoenosis, the high habitat heterogeneity and the geographical location of the Gazul mud volcano between different biogeographical regions. The best-represented species were Bathyarca philippiana, Asperarca nodulosa, Leptochiton sp., Astarte sulcata and Limopsis angusta. The thanatocoenosis harboured, with low frequency, species that are typical of northern latitudes, species indicating past seepage, species from the shelf and species restricted to particular hosts. The taxocoenosis found in different areas of Gazul (the mud volcano edifice, erosive de­pression and adjacent bottoms) generally displayed significant differences in multivariate analyses. Furthermore, the environmental parameters related to environmental complexity and food availability displayed the highest linkage with the molluscan fauna.Se estudiaron los moluscos del volcán de fango Gazul y sus zonas adyacentes, en el norte del Golfo de Cádiz, utili­zando diferentes métodos de muestreo. Este volcán de fango destaca por la presencia de hábitats vulnerables de aguas profundas y una alta biodiversidad potencial. Se identificaron un total de 232 especies de la taxocenosis y la tanatocenosis, de las cuales 86 son nuevas citas para el margen español del Golfo de Cádiz, tres de ellas son nuevas citas para aguas españolas y dos especies son nuevas para la ciencia. La alta riqueza de especies detectada podría estar relacionada con la combinación de diferentes mé­todos de muestreo, el estudio de la tanatocenosis, la alta heterogeneidad del hábitat y la ubicación geográfica del volcán de fango Gazul entre diferentes regiones biogeográficas. Las especies mejor representadas fueron Bathyarca philippiana, Asperarca nodulosa, Leptochiton sp., Astarte sulcata y Limopsis angusta. La tanatocenosis contenía, con baja frecuencia, especies típicas de latitudes superiores, especies indicadoras de emisiones pasadas, especies de la plataforma y especies restringidas a huéspedes particulares. La taxocenosis encontrada en las diferentes zonas de Gazul (edificio del volcán de fango, depresión erosiva y fon­dos adyacentes) generalmente mostró diferencias significativas en los análisis multivariantes. Además, los parámetros ambien­tales más vinculados con la malacofauna fueron los relacionados con la complejidad ambiental y la disponibilidad de alimento

    Análisis de la relevancia percibida del trabajo de planificación compartida de la atención a través de la instrumentalización con cartas

    Get PDF
    Objetivo: Desarrollo y evaluación de un instrumento capaz de medir la relevancia percibida del trabajo con cartas para el diálogo acerca de las preferencias en el proceso final de la vida. Método: Se ha construido la escala de la pertinencia percibida acerca del trabajo con cartas para las preferencias al final de la vida la cual ha sido evaluada mediante juicio de expertos y análisis factorial confirmatorio en una muestra de 320 estudiantes de Grado en Enfermería y 68 personas mayores de 40 años. Resultado: Se llega a una solución de 21 ítems, los cuales se ajustan en las 4 dimensiones teórica propuestas de manera óptima (CFI: 0,912; 0,842; 0,816; 0,995; RMSA: 0,170; 0,198; 0,187; 0,076). Conclusiones: La escala de medición de la pertinencia del trabajo con cartas es fiable y válida. Está compuesta por 4 dimensiones: Pertinencia percibida para la formación; Pertinencia percibida para el autoconocimiento; Pertinencia percibida para la aplicación en pacientes; e Iatrogenia percibida del instrumento).Objective: Development and evaluation of an instrument capable of measuring the perceived relevance of working with cards for the dialogue about preferences at the end stages of life. Method: A scale to measure the perceived relevance of working with cards for the conversation about preferences at the end of life was developed and evaluated through expert judgment and confirmatory factor analysis in a sample of 320 nursing degree students and 68 people older than 40 years. Result: A solution with 21 items was reached, which optimally fitted the four proposed theoretical dimensions (CFI: 0.912; 0.842; 0.816; 0.995; RMSA: 0.170; 0.198; 0.187; 0.076). Conclusions: The scale for measuring the relevance of working with cards is reliable and valid. It is made up of four dimensions: Perceived relevance for training; Perceived relevance for self-knowledge; Perceived relevance for application in patients; and Perceived iatrogenicity of the instrument).PreprintMedicin

    Late Pleistocene boreal molluscs in the Gulf of Cadiz: Past and current oceanographic implications

    Get PDF
    This subject is part of the doctoral dissertation of Olga Utrilla, supervised by Javier Urra and Serge Gofas. All three, together with José Luis Rueda, collaborated in the processing of the samples obtained in four deep-sea cruises, and in the conceptualization and writing of the first draft. In addition, Javier Urra selected and prepared samples for dating, obtained the funding for these and arranged for the analyses be done by Victor A. Valencia. Nieves López-González and Luis M. Fernández-Salas were expedition leaders in the INDEMARES deep-sea cruises and Javier Urra, Serge Gofas, Carlos Farias, Emilio González-García and José Luis Rueda participated in sample collection in one or another of the expeditions. These coauthors from IEO also contributed the discussions relating the fauna to oceanographic and geological factors.Remains of molluscs were collected from the seafloor on the north-eastern margin of the Gulf of Cadiz, between 300 and 1000 m water depth, using different sampling methods (e.g. dredging, trawling and box-coring), during several deep-sea expeditions. Samples contained a suite of species which nowadays mostly occur northwards of the English Channel, together with other widespread species. Species now locally extinct in the Gulf of Cadiz and restricted to northern latitudes, which unequivocally indicate a faunal shift, include the gastropods Buccinum undatum, Colus gracilis, Liomesus ovum and Neptunea antiqua, the bivalves Arctica islandica, Chlamys islandica, Modiolus modiolus, Mya truncata and Nuculana pernula and the scaphopod Antalis entalis. These species represent “Boreal Guests” of marked palaeoclimatic significance, some of which are reported for the first time in the Gulf of Cadiz. The boreal species collected were mostly large (>5 cm) whereas smaller boreal species were extremely scarce, probably winnowed away by strong bottom currents. The pteropod Limacina retroversa, at present restricted to water masses northwards of the Iberian Peninsula but widespread in Mediterranean sediments of the last glaciation, was also recorded. Accelerator mass spectrometry (AMS) 14C dates obtained from nine specimens of molluscs ranged between 26.1 and 14.6 kyr B.P., thus confirming their attribution to a last glacial assemblage. The abundance of these molluscan remains in the present Mediterranean Outflow Water pathway could be explained if this outflow was reduced in intensity or more likely shifted to a deeper level, leaving the upper slope in contact with suitable Atlantic intermediate waters. The findings of Boreal Guests in the Gulf of Cadiz document the continuity of the faunal shift which is well-known in the Mediterranean basin. Species still living in the Gulf of Cadiz and the Alboran Sea nevertheless account for 84.6% of specimens among the larger species.This study was supported by the INDEMARES/CHICA project with EC contract INDEMARES-LIFE (07/NAT/E/000732); the LIFE IP PAF INTEMARES project ‘‘Integrated, Innovative and Participatory Management for N2000 network in the Marine Environment’’ (LIFE15 IPE/ES/000012); and the 18-ESMARES2-CIRCA project “Monitoring and assessment of circalitoral and bathyal benthic habitats” from the C.N. Instituto Español de Oceanografía (IEO-CSIC), under the framework of the tasks assigned to the IEO-CSIC by the Ministerio de Transición Ecológica y Reto Demográfico (MITERD) of the Spanish government for the application of the Marine Strategy Framework Directive (MSFD) in Spanish waters. Funding for open access charge was provided by Universidad de Málaga / CBUA

    Vulnerable marine ecosystems and biological features of Gazul mud volcano (Gulf of Cádiz): A contribution towards a potential "Gulf of Cádiz" EBSA

    Get PDF
    The Gulf of Cádiz (GoC) represents an area of socioeconomic and scientific importance for oceanographic, geological and biological processes. An interesting feature of the GoC is the presence of a large amount of mud volcanoes (MVs) and diapirs that display different seepage, seabed types, oceanographic settings and biological communities. Detailed exploration of some MVs is still needed for detecting Vulnerable Marine ecosystems (VMEs) that seem to be rare in other areas of the GoC, improving the current knowledge on its biodiversity and ecological attributes. During different expeditions (MEDWAVES-ATLAS, INDEMARES-CHICA 0610 & 0412 and ISUNEPCA 0616) carried out in different years, biological samples and videos were obtained in Gazul MV (Spanish Margin of the GoC). The study of those samples and videos has revealed the presence of several ecologically important VMEs (e.g. 3 species of reef framework-forming corals, coral gardens including solitary scleractinians, gorgonians and antipatharians, as well as deep-sea sponge aggregations and chemosynthesis-related structures) and a large number of species occurring in this MV, including new records for the European margin, threatened species and non-previously described species. The combination of different environmental and anthropogenic factors allowed the present-day persistence of these VMEs in the GoC. Some of Gazul MV biological and ecological attributes fit several criteria of the Convention on Biological Diversity for EBSA description (e.g. 1,3,4,6) that, together with those of other areas of the GoC, may contribute to the future potential nomination of an EBSA in this area of the NE Atlantic

    Reproduction of the anthozoan Anemonia sulcata (Pennant, 1777) in southern Spain: from asexual reproduction to putative maternal care

    No full text
    Anemonia sulcata (Pennant, 1777) is a common shallow water cnidarian from rocky platform and boulder beaches in southern Spain, where it is a popular seafood item with an increasing fshery. To aid in the management of a sustainable fshery, a study on the reproduction of A. sulcata in the littoral of Malaga (southern Spain) was performed from November 2014 to September 2015, using histological methods. A total of 123 specimens were examined, with a size range (as diameter of the pedal disc) from 1.1 to 48.2 mm. The sex ratio was signifcantly biased to females, with 1.7 females: 1 male (χ2=4.45, p<0.01). The spermatozoids and oocytes arise from the endodermal cells. The mature oocytes receive nutritive flaments (trophonema) from the endoderm cells. There were zooxanthellae in the mesenteries, tentacles and also inside the oocytes. A gastrula was observed in one individual, as well as several planula larvae in diferent degree of development in others. Asexual reproduction by internal budding was observed in some individuals. The studied population showed an extended reproductive cycle with a peak of spawning in April. The size and weight of sexual maturity of the studied population were 21.5 mm and 16.5 g, respectively. A positive signifcant correlation was observed between size and weight of individuals. We suggest that the diameter of the pedal disc should be used as the legal parameter for the management of this fshery, as this measurement is easier to take by fshermen at sea than the weight, the current legal parameter

    Preliminary characterization of Vulnerable Marine Ecosystems and associated communities of Chella Bank (Alboran Sea, W Mediterranean)

    No full text
    Poster presentation at ATLAS 3rd General Assembly. Seamounts may promote the presence of vulnerable marine ecosystems (VMEs) worldwide. In the Alboran Sea (W Mediterranean Sea), the Chella Bank (locally known as “Seco de los Olivos”) is a seamount that covers ca. 100 km2 and is under the influence of different water masses in this important Atlanto-Mediterranean biogeographical transition zone. During the MEDWAVES expedition (September-October 2016) within the frame of the H2020 ATLAS project, biological and sediment samples collected with Van Veen dredge and ROV underwater videos were obtained in sedimentary and coral rubble bottoms of Chella Bank. The analyses have revealed a diverse invertebrate community associated with these bottoms containing abundant cold-water coral (CWC) remains (mainly Madrepora oculata and Lophelia pertusa), which provide complex heterogeneous microhabitats to many different taxa. The community associated with the coral rubble bottoms is mainly composed of different genera of bivalves (Mendicula, Limopsis, Asperarca), gastropods (Gibberula, Epitonium), small crustaceans (class Malacostraca), polychaetes (Eunice), ophiuroideans (Ophiothrix), bryozoans (order Cyclostomata), hydrozoans (Cryptolaria), poriferans (Terpios, Haliclona) and brachiopods (Megathiris, Megerlia), among other taxa. Furthermore, the megafauna include cnidarians (Bebryce, Acanthogorgia, Dendrophyllia), sponges (Pachastrella) and dense shoals of the carangid fish Caranx rhonchus. Unlike coral rubble bottoms, macro- and micro-fauna inhabiting close sandy, muddy or hemipelagic muddy habitats seems less diverse (up to four times in terms of abundance and species richness). These communities are mainly composed of polychaetes, small crustaceans and bivalves (Abra, Ennucula, Yoldiella), together with shoals of the ammodytid fish Gymnammodytes cicerelus. Coral rubble bottoms of Chella Bank may therefore represent an interesting habitat for conservation, harboring a good representation of the biodiversity linked to CWC communities. This study increases the scarce information on biodiversity and biogeography (WP3) for this area that probably favors the connectivity of CWC associated fauna (WP4) between the Atlantic and Mediterranean basins

    New advances in the study of the biodiversity of the SCI “Volcanes de fango del golfo de Cádiz” (southwestern Spanish Margin)

    Get PDF
    The Gulf of Cádiz represents an important seepage area with ca. 70 mud volcanoes (MV), of which one third are located in European waters (Spain and Portugal). Previous projects and expeditions resulted on a large amount of information on different aspects of MV of the Moroccan margin, which seem to have a higher seepage activity than those of the Iberian margin. Those studies mainly focused on their geological characteristics, whereas others offered novel information on their associated biota, especially the endosymbiont-bearing invertebrates as well as non-previously described species (Vanreusel et al. 2009). In 2014, the MV of the Spanish margin of the Gulf of Cádiz were included in the Natura 2000 network (Site of Community Importance - SCI "Volcanes de fango del golfo de Cádiz" - ESZZ12002) under the framework of the Life + project INDEMARES. Nowadays, the LIFE IP PAF INTEMARES project represents an opportunity for improving the knowledge on the biodiversity of this SCI

    Vulnerable marine ecosystems and biological features of Gazul mud volcano (Gulf of Cádiz): A contribution towards a potential "Gulf of Cádiz" EBSA

    No full text
    The Gulf of Cádiz (GoC) represents an area of socioeconomic and scientific importance for oceanographic, geological and biological processes. An interesting feature of the GoC is the presence of a large amount of mud volcanoes (MVs) and diapirs that display different seepage, seabed types, oceanographic settings and biological communities. Detailed exploration of some MVs is still needed for detecting Vulnerable Marine ecosystems (VMEs) that seem to be rare in other areas of the GoC, improving the current knowledge on its biodiversity and ecological attributes. During different expeditions (MEDWAVES-ATLAS, INDEMARES-CHICA 0610 & 0412 and ISUNEPCA 0616) carried out in different years, biological samples and videos were obtained in Gazul MV (Spanish Margin of the GoC). The study of those samples and videos has revealed the presence of several ecologically important VMEs (e.g. 3 species of reef framework-forming corals, coral gardens including solitary scleractinians, gorgonians and antipatharians, as well as deep-sea sponge aggregations and chemosynthesis-related structures) and a large number of species occurring in this MV, including new records for the European margin, threatened species and non-previously described species. The combination of different environmental and anthropogenic factors allowed the present-day persistence of these VMEs in the GoC. Some of Gazul MV biological and ecological attributes fit several criteria of the Convention on Biological Diversity for EBSA description (e.g. 1,3,4,6) that, together with those of other areas of the GoC, may contribute to the future potential nomination of an EBSA in this area of the NE Atlantic
    corecore