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Characterizing the virulence of entomopathogenic nematodes against wireworms
No full textTrabajo presentado en el XXVII International Congress of Entomology, celebrado en Kyoto (Japón), del 25 al 30 de agosto de 202
Sand and dust storms: a growing global health threat calls for international health studies to support policy action
Get PDFSand and dust storms increasingly threaten global environmental and public health. To date, 150 countries are directly affected, with more than 100 classified as non-dust source regions. With climate change, these storms are expected to become more frequent and severe. Despite international awareness and initiatives, such as those led by the UN, crucial knowledge gaps continue to hinder effective, evidence-based public responses to sand and dust storms. In this Viewpoint, we review existing gaps in health research and highlight four key research priorities: the comprehensive health effects of sand and dust storms, including short-term and long-term exposures, diseases, regions, and health outcomes; the key particle sizes and toxic components of particles during sand and dust storms; the design of multicentre studies accounting for region-specific exposure patterns; and research on health outcomes attributable to particulate matter mixtures dominated by windblown dust versus other sources. We urgently call for international, collaborative, and multidisciplinary health studies considering sand and dust storm exposure characteristics and for the adoption of scientifically robust epidemiological methods in these studies.This study was supported by the National Natural Science Foundation of China (82425051 and 82241051; TL), the National Key R&D Program of China (2023YFC3708302; QL), the Chinese Academy of Sciences Project for Young Scientists in Basic Research (YSBR-086; QL), and the National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases (2024NITFID407; CZ and 2024NITFID601; TL). The views expressed in the article are those of the authors and do not necessarily reflect the views of the Health Effects Institute, or its sponsors.Peer reviewe
The Gaia -ESO Survey: Stellar radii in the young open clusters NGC 2264, NGC 2547, and NGC 2516
Get PDFContext. Rapidly rotating, low-mass members of eclipsing binary systems have measured radii that are significantly larger than predicted by standard evolutionary models. It has been proposed that magnetic activity is responsible for this radius inflation. Aims. By estimating the radii of low-mass stars in three young clusters (NGC 2264, NGC 2547, NGC 2516, with ages of ∼5, ∼35 and ∼140 Myr respectively), we aim to establish whether similar radius inflation is seen in single, magnetically active stars. Methods. We use radial velocities from the Gaia-ESO Survey (GES) and published photometry to establish cluster membership and then combine GES measurements of projected equatorial velocities with published rotation periods to estimate the average radii for groups of fast-rotating cluster members as a function of their luminosity and age. The average radii are compared with the predictions of both standard evolutionary models and variants that include magnetic inhibition of convection and starspots. Results. At a given luminosity, the stellar radii in NGC 2516 and NGC 2547 are larger than predicted by standard evolutionary models at the ages of these clusters. The discrepancy is least pronounced and not significant (10 per cent) in zero age main sequence stars with radiative cores, but more significant in lower-mass, fully convective pre main-sequence cluster members, reaching 30 ± 10 per cent. The uncertain age and distance of NGC 2264 preclude a reliable determination of any discrepancy for its members. Conclusions. The median radii we have estimated for low-mass fully convective stars in the older clusters are inconsistent (at the 2-3σ level) with non-magnetic evolutionary models and more consistent with models that incorporate the effects of magnetic fields or dark starspots. The available models suggest this requires either surface magnetic fields exceeding 2.5 kG, spots that block about 30 per cent of the photospheric flux, or a more moderate combination of both. © ESO, 2016.R.J.J. wishes to thank the UK Science and Technology Facilities Council for financial support. Based on data products from observations made with ESO Telescopes at the La Silla Paranal Observatory under programme ID 188.B-3002. These data products have been processed by the Cambridge Astronomy Survey Unit (CASU) at the Institute of Astronomy, University of Cambridge, and by the FLAMES/UVES reduction team at INAF/Osservatorio Astrofisico di Arcetri. These data have been obtained from the Gaia-ESO Survey Data Archive, prepared and hosted by the Wide Field Astronomy Unit, Institute for Astronomy, University of Edinburgh, which is funded by the UK Science and Technology Facilities Council. This work was partly supported by the European Union FP7 programme through ERC grant number 320360 and by the Leverhulme Trust through grant RPG-2012-541. We acknowledge the support from INAF and Ministero dell’Istruzione, dell’Università’ e della Ricerca (MIUR) in the form of the grant “Premiale VLT 2012”. The results presented here benefit from discussions held during the Gaia-ESO workshops and conferences supported by the ESF (European Science Foundation) through the GREAT Research Network Programme
Reductive head-to-head coupling of phenylacetylenes in the coordination sphere of an osmium-polyhydride
No full textComplex OsH6(PiPr3)2 releases H2 at 50 °C. The resulting tetrahydride OsH4(PiPr3)2 promotes head-to-head reductive dimerization of phenylacetylenes to give the 1,4-dibranched-butenediyl derivatives OsH2{η4-[C4H4R2]}(PiPr3)2 (R = C6H5, C6H4–CF3, C6H4–NMe2). DFT calculations suggest that the formation of these compounds proceeds via five-coordinate unsaturated bis(alkenyl)-osmium(II)-(Kubas-type dihydrogen) intermediates, which evolve by alkenyl coupling and H–H cleavage of the dihydrogen. The reactions are sensitive to temperature and the amount of alkyne used. At higher temperatures and excess alkyne, the reductive coupling is accompanied by two dehydrogenation reactions, one at the metal center and the other involving an isopropyl substituent of a phosphine. As a result, mixtures of the dihydrides and Os{η4-[C4H4R2]}(PiPr3){η2-C,C;κ1-P-[(CH2═CMe)PiPr2]}(PiPr3) (R = H, CF3, NMe2) are formed. Both families react with H2 to regenerate OsH6(PiPr3)2 and release the corresponding 1,4-diarylbutane. According to these reactions, 1,4-diarylbutanes have been obtained in approximately 20% yield, by stirring phenylacetylenes with 5 mol % of OsH6(PiPr3)2, in toluene, under 1 atm of H2.Financial support from the MICIN/AEI/10.13039/501100011033 (PID2020-115286GB-I00, PID2023-146967NB-I00, and RED2022-134287-T), Gobierno de Aragón (E06_23R), FEDER, and the European Social Fund is acknowledged. S.G.C. thanks the European Union-NextGenerationEU and Spanish University Ministry for her “Margarita Salas” contract.Peer reviewe
Clinoform development during the Holocene highstand: The case of the southeastern Brazil inner continental shelf
No full textPóster presentado en XIX Congresso da Associação Brasileira de Estudos do Quaternário: ABEQUA, 9-13 sep. 2024 Natal (Brasil)The Holocene highstand sedimentation in the inner continental shelf of southeastern Brazil, between São Sebastião Island (SSI) and Ubatuba, is composed by clinoforms prograding obliquely and longitudinally to the shoreline. These clinoforms exhibit a typically sigmoidal configuration, overlying wave ravinement surfaces (WRS), and exhibit distinct internal structures and progradation styles. The study area is characterized by two physiographic compartments separated by a chain of SW-NE
trending islands: (i) the inner compartment, located between the shoreline and the 30-35 m isobaths, is topographically lowered and geomorphologically embayed, limited to the southwest by the SSI; (ii) the outer compartment extends from 35-40 m water depths to the boundary between the inner and outer continental shelf located at 60-70 m water depths. The clinoform located in the inner compartment is narrow and elongated, oriented approximately N-S, and slightly oblique to the shoreline. Its bathymetric expression is observed from the 10 m isobath, where it presents an average thickness of 4 m to a maximum thickness of 8 m at 16-20 m water depths.
The inner clinoform progressively thins seaward to 30-35 m water depths. Internally it exhibits a sigmoidal progradational pattern downlapping the underlying WRS. The clinoform in the outer compartment is oriented SW-NE, longitudinally to the shoreline at water depths of 35-60 m, extending for around 32 km, with an average width of 15 km. This outer clinoform exhibits a compound sigmoidal-oblique configuration. Its lower portion is characterized by oblique reflectors at the base with toplap truncation at the top and downlap at the bottom, evolving upwards to a sigmoidal configuration. At water depths of 35-40 m, the inner clinoform is located between SSI and Búzios island, partially overlying the outer clinoform, generating a amalgamated clinoform pattern with crossing growth trajectories. This arrangement suggests multiple sediment sources for clinoform development. The inner clinoform would have been fed by local sediment sources, like small rivers that flow into the region. In contrast, the outer clinoform seems to have been fed by sediments from more distant sources brought to the area by a shelf-moving current such as the Brazilian Coastal Current
Effect of ocean biogeochemical conditions on barium sulfate precipitation: an experimental study
No full textComunicación oral presentada en 11th Granada-Münster Discussion Meeting, 27 al 29 de noviembre de 202
An h-principle for embeddings transverse to a contact structure
No full textGiven a class of embeddings into a contact or a symplectic manifold, we give a sufficient condition, that we call isocontact or isosymplectic realization, for this class to satisfy a general (Formula presented.) -principle. The flexibility follows from the (Formula presented.) -principles for isocontact and isosymplectic embeddings, it provides a framework for classical results, and we give two new applications. Our main result is that embeddings transverse to a contact structure satisfy a full (Formula presented.) -principle in two cases: if the complement of the embedding is overtwisted, or when the intersection of the image of the formal derivative with the contact structure is strictly contained in a proper symplectic subbundle. We illustrate the general framework on symplectic manifolds by studying the universality of Hamiltonian dynamics on regular level sets via a class of embeddings.Robert Cardona acknowledges financial support from the Margarita Salas postdoctoral contract
financed by the European Union-NextGenerationEU, as well as from the LabEx IRMIA and the
Universit´e de Strasbourg. This work was partially supported by the AEI grant PID2019-103849GBI00 / AEI / 10.13039/501100011033 and the AGAUR grant 2021SGR00603.
Francisco Presas is supported by the grant reference number PID2019-108936GB-C21
(MINECO/FEDER). This work was partially supported by the ICMAT–Severo Ochoa grant
CEX2019-000904-S..Peer reviewe
KINEMATICS of EXTREMELY METAL-POOR GALAXIES: EVIDENCE for STELLAR FEEDBACK
No full textThe extremely metal-poor (XMP) galaxies analyzed in a previous paper have large star-forming regions with a metallicity lower than the rest of the galaxy. Such a chemical inhomogeneity reveals the external origin of the metal-poor gas fueling star formation, possibly indicating accretion from the cosmic web. This paper studies the kinematic properties of the ionized gas in these galaxies. Most XMPs have a rotation velocity around a few tens of km s. The star-forming regions appear to move coherently. The velocity is constant within each region, and the velocity dispersion sometimes increases within the star-forming clump toward the galaxy midpoint, suggesting inspiral motion toward the galaxy center. Other regions present a local maximum in velocity dispersion at their center, suggesting a moderate global expansion. The H line wings show a number of faint emission features with amplitudes around a few per cent of the main H component, and wavelength shifts between 100 and 400 km s. The components are often paired, so that red and blue emission features with similar amplitudes and shifts appear simultaneously. Assuming the faint emission to be produced by expanding shell-like structures, the inferred mass loading factor (mass loss rate divided by star formation rate) exceeds 10. Since the expansion velocity far exceeds the rotational and turbulent velocities, the gas may eventually escape from the galaxy disk. The observed motions involve energies consistent with the kinetic energy released by individual core-collapse supernovae. Alternative explanations for the faint emission have been considered and discarded. © 2017. The American Astronomical SocietyThanks are due to R. Amorín, Y. Ascasibar, A. B. MoralesLuis, P. Papaderos, and J. Vílchez, who participated in the target
selection and in some of the observing time proposals that
produced the spectra analyzed in the paper. We also thank an
anonymous referee whose comments helped to improve the
readability of the paper. This article is based on observations
made with the WHT operated by the ING in the Observatorio del
Roque de los Muchachos, La Palma, Spain. This work has been
partly funded by the Spanish Ministry of Economy and
Competitiveness, projects Estallidos AYA2013–47742–
C04–02–P and AYA2013–47742–C04–01–P. A.O.-G. thanks
Fundación La Caixa for financial support in the form of a PhD contract. M.E.F. is partly funded by the Estallidos project, as well
as by the Fundao para a Cincia e Tecnologia (FCTPortugal),
through the research grant SFRH/BPD/107801/2015. J.M.-A.
acknowledges support from the European Research Council
Starting Grant (SEDmorph; P.I. V. Wild).Peer reviewe
Paternity leave and early child developmen
No full textTrabajo presentado en el Workshop on Early Investments, Family Well-Being, and Child Development, celebrado en Rødvig (Dinamarca), del 28 al 30 de agosto de 202
Oxidative Inactivation and Modification of Glutamine synthetase in in vitro models of Alzheimer Disease
No full textTrabajo presentado en la 31st SfRBM Annual Conference (Society for Redox Biology and Medicine’s), celebrada en Savannah, Georgia (Estados Unidos), del 20 al 23 de noviembre de 202