326 research outputs found

    XIPE: the x-ray imaging polarimetry explorer

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    XIPE, the X-ray Imaging Polarimetry Explorer, is a mission dedicated to X-ray Astronomy. At the time of writing XIPE is in a competitive phase A as fourth medium size mission of ESA (M4). It promises to reopen the polarimetry window in high energy Astrophysics after more than 4 decades thanks to a detector that efficiently exploits the photoelectric effect and to X-ray optics with large effective area. XIPE uniqueness is time-spectrally-spatially-resolved X-ray polarimetry as a breakthrough in high energy astrophysics and fundamental physics. Indeed the payload consists of three Gas Pixel Detectors at the focus of three X-ray optics with a total effective area larger than one XMM mirror but with a low weight. The payload is compatible with the fairing of the Vega launcher. XIPE is designed as an observatory for X-ray astronomers with 75 % of the time dedicated to a Guest Observer competitive program and it is organized as a consortium across Europe with main contributions from Italy, Germany, Spain, United Kingdom, Poland, Sweden

    Early Eocene deep-sea benthic foraminiferal faunas: recovery from the Paleocene Eocene Thermal Maximum extinction in a greenhouse world

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    The early Eocene greenhouse world was marked by multiple transient hyperthermal events. The most extreme was the Paleocene-Eocene Thermal Maximum (PETM, ~56 Ma), linked to the extinction of the globally recognised deep-sea benthic foraminiferal Velasco fauna, which led to the development of early Eocene assemblages. This turnover has been studied at high resolution, but faunal development into the later early Eocene is poorly documented. There is no widely accepted early Eocene equivalent of the Late Cretaceous-Paleocene Velasco fauna, mainly due to the use of different taxonomic concepts. We compiled Ypresian benthic foraminiferal data from 17 middle bathyal-lower abyssal ocean drilling sites in the Pacific, Atlantic and Indian Oceans, in order to characterise early Eocene deep-sea faunas by comparing assemblages across space, paleodepth and time. Nuttallides truempyi, Oridorsalis umbonatus, Bulimina trinitatensis, the Bulimina simplex group, the Anomalinoides spissiformis group, pleurostomellids, uniserial lagenids, stilostomellids and lenticulinids were ubiquitous during the early Eocene (lower-middle Ypresian). Aragonia aragonensis, the Globocassidulina subglobosa group, the Cibicidoides eocaenus group and polymorphinids became ubiquitous during the middle Ypresian. The most abundant early Ypresian taxa were tolerant to stressed or disturbed environments, either by opportunistic behavior (Quadrimorphina profunda, Tappanina selmensis, Siphogenerinoides brevispinosa) and/or the ability to calcify in carbonate-corrosive waters (N. truempyi). Nuttallides truempyi, T. selmensis and other buliminids (Bolivinoides cf. decoratus group, Bulimina virginiana) were markedly abundant during the middle Ypresian. Contrary to the long-lived, highly diverse and equitable Velasco fauna, common and abundant taxa reflect highly perturbed assemblages through the earliest Ypresian, with lower diversity and equitability following the PETM extinction. In contrast, the middle Ypresian assemblages may indicate a recovering fauna, though to some extent persistently disturbed by the lower-amplitude Eocene hyperthermals (e.g., Eocene Thermal Maximum 2 and 3). We propose the name ‘Walvis Ridge fauna’ for future reference to these Ypresian deep-sea benthic foraminiferal assemblages

    The Late Miocene-Early Pliocene Biogenic Bloom: An Integrated Study in the Tasman Sea

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    The Late Miocene-Early Pliocene Biogenic Bloom (∼9–3.5 Ma) was a paleoceanographic phenomenon defined by anomalously high accumulations of biological components at multiple open ocean sites, especially in certain regions of the Indian, and Pacific oceans. Its temporal and spatial extent with available information leaves fundamental questions about driving forces and responses unanswered. In this work, we focus on the middle part of the Biogenic Bloom (7.4–4.5 Ma) at International Ocean Discovery Program Site U1506 in the Tasman Sea, where we provide an integrated age model based on orbital tuning of the Natural Gamma Radiation, benthic foraminiferal oxygen isotopes, and calcareous nannofossil biostratigraphy. Benthic foraminiferal assemblages suggest changes in deep water oxygen concentration and seafloor nutrient supply during generally high export productivity conditions. From 7.4 to 6.7 Ma, seafloor conditions were characterized by episodic nutrient supply, perhaps related to seasonal phytoplankton blooms. From 6.7 to 4.5 Ma, the regime shifted to a more stable interval characterized by eutrophic and dysoxic conditions. Combined with seismic data, a regional change in paleoceanography is inferred at around 6.7 Ma, from stronger and well-oxygenated bottom currents to weaker, oxygen-depleted bottom currents. Our results support the hypothesis that the Biogenic Bloom was a complex, multiphase phenomenon driven by changes in ocean currents, rather than a single uniform period of sustained sea surface water productivity. Highly resolved studies are thus fundamental to its understanding and the disentanglement of local, regional, and global imprints

    Conocimientos sobre anticoncepción en mujeres menores de 20 años

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    Many teenagers start having sex without having received accurate information about sexuality and reproductive health. This lack of information is responsible for the high incidence of unplanned pregnancies and sexually transmitted diseases that are currently reported. There are many medical risks associated with early pregnancy, so it is important to conduct studies on the knowledge that teens have about contraception, and the consequences of a pregnancy at this stage of life. Sex education is to prepare the new generations for love, marriage and family, so it must be part of the education of the whole personality, with participation of the community.Muchos adolescentes comienzan a tener relaciones sexuales sin haber recibido información exacta sobre la sexualidad y la salud reproductiva; esta falta de información es responsable de la alta incidencia de embarazos no planificados y de enfermedades de transmisión sexual que se informan en la actualidad. Son numerosos los riesgos médicos asociados con el embarazo precoz, por lo que es importante realizar estudios sobre el conocimiento que los adolescentes tienen sobre métodos anticonceptivos y las consecuencias de un embarazo en esta etapa de la vida. La educación sexual consiste en preparar a las nuevas generaciones para el amor, el matrimonio y la familia, por lo que debe formar parte de la educación integral de la personalidad, con participación de la comunidad

    Regulación menstrual en mujeres menores de 20 años

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    The practice of abortion has accompanied mankind since time immemorial. It is the oldest method known to man to end an unwanted pregnancy. An abortion is the termination of pregnancy in the first 20 weeks or the expulsion of the product of conception that weighs less than 500g. Menstrual regulation has been used for birth control. Among the factors influencing pregnancy in women under 20 years of age it is the non-use of contraception or its failure. Menstrual regulation is more frequent between 14-16 years of age and in those that have no steady partner. The most common causes that motivate pregnancy termination are: continue studying, contraceptive failure, work, marital instability and family problems. It is important to give a warning to the Ministries of Education and Health to promote sexual education in the curriculum at all levels of education to avoid this procedure.La práctica del aborto acompaña a la humanidad desde épocas inmemoriales; el aborto es el método más antiguo conocido por el hombre para terminar un embarazo no deseado y es la interrupción de la gestación en las primeras 20 semanas o la expulsión del producto de la concepción con un peso menor de 500g. La regulación menstrual ha sido utilizada para el control de la natalidad. Entre los factores que influyen en el embarazo en menores de 20 años se encuentra la no utilización de métodos anticonceptivos o su fallo; la regulación menstrual es más frecuente en jóvenes entre 14-16 años que no tienen pareja estable y las causas más frecuentes que motivan la interrupción del embarazo son la continuación de los estudios, el fallo del anticonceptivo, trabajar, la inestabilidad matrimonial y los problemas familiares. Es importante dar un alerta a los Ministerios de Educación y Salud para fomentar la educación sexual como programa de estudio en todos los niveles de enseñanza para evitar este procedimiento

    A DNA damage repair gene-associated signature predicts responses of patients with advanced soft-tissue sarcoma to treatment with trabectedin

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    Signatura genètica; Biomarcadors predictius; TrabectedinaFirma genética; Biomarcadores predictivos; TrabectedinaGene signature; Predictive biomarkers; TrabectedinPredictive biomarkers of trabectedin represent an unmet need in advanced soft-tissue sarcomas (STS). DNA damage repair (DDR) genes, involved in homologous recombination or nucleotide excision repair, had been previously described as biomarkers of trabectedin resistance or sensitivity, respectively. The majority of these studies only focused on specific factors (ERCC1, ERCC5, and BRCA1) and did not evaluate several other DDR-related genes that could have a relevant role for trabectedin efficacy. In this retrospective translational study, 118 genes involved in DDR were evaluated to determine, by transcriptomics, a predictive gene signature of trabectedin efficacy. A six-gene predictive signature of trabectedin efficacy was built in a series of 139 tumor samples from patients with advanced STS. Patients in the high-risk gene signature group showed a significantly worse progression-free survival compared with patients in the low-risk group (2.1 vs 6.0 months, respectively). Differential gene expression analysis defined new potential predictive biomarkers of trabectedin sensitivity (PARP3 and CCNH) or resistance (DNAJB11 and PARP1). Our study identified a new gene signature that significantly predicts patients with higher probability to respond to treatment with trabectedin. Targeting some genes of this signature emerges as a potential strategy to enhance trabectedin efficacy.This study was funded by the Spanish Group for Research on Sarcoma (GEIS) and partially by PharmaMar. The authors would like to thank the GEIS data center for data management. The authors also thank the donors and the Hospital Universitario Virgen del Rocío—Instituto de Biomedicina de Sevilla Biobank (Andalusian Public Health System Biobank and ISCIII-Red de Biobancos PT17/0015/0041) for part of the human specimens used in this study. David S. Moura is recipient of a Sara Borrell postdoctoral fellowship funded by the National Institute of Health Carlos III (ISCIII) (CD20/00155)

    Dynamics of sediment flux to a bathyal continental margin section through the Paleocene–Eocene Thermal Maximum

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    The response of the Earth system to greenhouse-gas-driven warming is of critical importance for the future trajectory of our planetary environment. Hyperthermal events – past climate transients with global-scale warming significantly above background climate variability – can provide insights into the nature and magnitude of these responses. The largest hyperthermal of the Cenozoic was the Paleocene–Eocene Thermal Maximum (PETM ∼ 56 Ma). Here we present new high-resolution bulk sediment stable isotope and major element data for the classic PETM section at Zumaia, Spain. With these data we provide a new detailed stratigraphic correlation to other key deep-ocean and terrestrial PETM reference sections. With this new correlation and age model we are able to demonstrate that detrital sediment accumulation rates within the Zumaia continental margin section increased more than 4-fold during the PETM, representing a radical change in regional hydrology that drove dramatic increases in terrestrial-to-marine sediment flux. Most remarkable is that detrital accumulation rates remain high throughout the body of the PETM, and even reach peak values during the recovery phase of the characteristic PETM carbon isotope excursion (CIE). Using a series of Earth system model inversions, driven by the new Zumaia carbon isotope record, we demonstrate that the silicate weathering feedback alone is insufficient to recover the PETM CIE, and that active organic carbon burial is required to match the observed dynamics of the CIE. Further, we demonstrate that the period of maximum organic carbon sequestration coincides with the peak in detrital accumulation rates observed at Zumaia. Based on these results, we hypothesise that orbital-scale variations in subtropical hydro-climates, and their subsequent impact on sediment dynamics, may contribute to the rapid climate and CIE recovery from peak-PETM conditions

    The late Miocene-early Pliocene biogenic bloom: an integrated study in the Tasman sea

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    The Late Miocene-Early Pliocene Biogenic Bloom (∼9–3.5 Ma) was a paleoceanographic phenomenon defined by anomalously high accumulations of biological components at multiple open ocean sites, especially in certain regions of the Indian, and Pacific oceans. Its temporal and spatial extent with available information leaves fundamental questions about driving forces and responses unanswered. In this work, we focus on the middle part of the Biogenic Bloom (7.4–4.5 Ma) at International Ocean Discovery Program Site U1506 in the Tasman Sea, where we provide an integrated age model based on orbital tuning of the Natural Gamma Radiation, benthic foraminiferal oxygen isotopes, and calcareous nannofossil biostratigraphy. Benthic foraminiferal assemblages suggest changes in deep water oxygen concentration and seafloor nutrient supply during generally high export productivity conditions. From 7.4 to 6.7 Ma, seafloor conditions were characterized by episodic nutrient supply, perhaps related to seasonal phytoplankton blooms. From 6.7 to 4.5 Ma, the regime shifted to a more stable interval characterized by eutrophic and dysoxic conditions. Combined with seismic data, a regional change in paleoceanography is inferred at around 6.7 Ma, from stronger and well-oxygenated bottom currents to weaker, oxygen-depleted bottom currents. Our results support the hypothesis that the Biogenic Bloom was a complex, multiphase phenomenon driven by changes in ocean currents, rather than a single uniform period of sustained sea surface water productivity. Highly resolved studies are thus fundamental to its understanding and the disentanglement of local, regional, and global imprints
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