805 research outputs found

    Marine viruses discovered via metagenomics shed light on viral strategies throughout the oceans

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    Marine viruses are key drivers of host diversity, population dynamics and biogeochemical cycling and contribute to the daily flux of billions of tons of organic matter. Despite recent advancements in metagenomics, much of their biodiversity remains uncharacterized. Here we report a data set of 27,346 marine virome contigs that includes 44 complete genomes. These outnumber all currently known phage genomes in marine habitats and include members of previously uncharacterized lineages. We designed a new method for host prediction based on co-occurrence associations that reveals these viruses infect dominant members of the marine microbiome such as Prochlorococcus and Pelagibacter. A negative association between host abundance and the virus-to-host ratio supports the recently proposed Piggyback-the-Winner model of reduced phage lysis at higher host densities. An analysis of the abundance patterns of viruses throughout the oceans revealed how marine viral communities adapt to various seasonal, temperature and photic regimes according to targeted hosts and the diversity of auxiliary metabolic genes.CAPESCNPqFAPERJCiencia sem fronteiras programUniv Fed Rio de Janeiro, IB, BR-21944970 Rio de Janeiro, BrazilRadboud Univ Nijmegen, Radboud Inst Mol Life Sci, CMBI, Med Ctr, NL-6500 HB Nijmegen, NetherlandsUniv Utrecht, Theoret Biol & Bioinformat, NL-3584 CH Utrecht, NetherlandsSan Diego State Univ, Dept Biol, San Diego, CA 92182 USAUniv Fed Sao Paulo UNIFESP, Dept Ciencias Mar, BR-11070100 Baixada Santista, BrazilNIOZ Royal Netherlands Inst Sea Res, Dept Marine Microbiol & Biogeochem, POB 59, NL-1790 AB Den Burg, NetherlandsUniv Utrecht, POB 59, NL-1790 AB Den Burg, NetherlandsUniv Amsterdam, Dept Aquat Microbiol, IBED, NL-1090 GE Amsterdam, NetherlandsUniv Fed Rio de Janeiro, COPPE, SAGE, BR-21941950 Rio de Janeiro, BrazilUniv Fed Sao Paulo UNIFESP, Dept Ciencias Mar, BR-11070100 Baixada Santista, BrazilCAPESCNPqFAPERJCiencia sem fronteiras program: 864.14.004Web of Scienc

    Did Egret Detect Distant Supernova Remnants?

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    It might be thought that supernova remnants (SNRs) more distant than a few kiloparsec from Earth could not have been detected by the EGRET experiment. This work analyzes the observational status of this statement in the light of new CO studies of SNRs.Comment: Accepted for publication in Advances in Space Research, in High Energy Studies of Supernova Remnants and Neutron Stars, eds. W. Becker and W. Hermsen (2003

    MODELOS DE TECNOLOGIAS DEL BIG DATA ANALYTICS Y SU APLICACIÓN EN SALUD

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    ResumenBig Data Analytics se refiere al almacenamiento, administración y análisis de grandes volúmenes de datos a través de métodos estadísticos o científicos para descubrir relaciones entre los datos. Recientemente se ha aplicado al campo de la salud, pero, ¿Qué tecnologías de big data aplicar a campos específicos en salud? El presente trabajo identifica áreas de oportunidad en salud que se benefician del big data Analytics, como la medicina personalizada, registros de salud, estancias y readmisiones de pacientes y biomedicina. También, se presenta una propuesta de modelo que conjunta plataformas tecnológicas (Hadoop, Mahout, Spark), algoritmos (Filtrado colaborativo, árboles de decisión, clustering) y campos de salud. Como ejemplo, se aplica el modelo propuesto en el caso del monitoreo a distancia de la salud de un paciente con problemas del corazón, como una base para su implementación real en un trabajo futuro.Palabras Claves: Big data, modelo tecnológico, salud.MODELS OF TECHNOLOGIES OF BIG DATA ANALYTICS AND ITS APPLICATION IN HEALTHAbstractBig Data Analytics refers to the storage, management and analysis of large volumes of data through statistical or scientific methods to discover relationships between data. Recently it has been applied to the field of healthcare, but, What big data technologies apply to specific fields in healthcare? This paper identifies areas of opportunity in healthcare that benefit from the big data analytics, such as personalized medicine, health records, stays and readmissions of patients and biomedicine. Also, a model proposal is presented that combines technological platforms (Hadoop, Mahout, Spark), algorithms (Collaborative filtering, decision trees, clustering) and health fields. An application of the model in relation to the remote monitoring of the patient’s health with heart problems illustrates its use, as a basis for its implementation in future work.Keywords: Big data, healthcare, technological model

    Epidemiology, patterns of care, and mortality for patients with acute respiratory distress syndrome in intensive care units in 50 countries

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    IMPORTANCE: Limited information exists about the epidemiology, recognition, management, and outcomes of patients with the acute respiratory distress syndrome (ARDS). OBJECTIVES: To evaluate intensive care unit (ICU) incidence and outcome of ARDS and to assess clinician recognition, ventilation management, and use of adjuncts-for example prone positioning-in routine clinical practice for patients fulfilling the ARDS Berlin Definition. DESIGN, SETTING, AND PARTICIPANTS:The Large Observational Study to Understand the Global Impact of Severe Acute Respiratory Failure (LUNG SAFE) was an international, multicenter, prospective cohort study of patients undergoing invasive or noninvasive ventilation, conducted during 4 consecutive weeks in the winter of 2014 in a convenience sample of 459 ICUs from 50 countries across 5 continents. EXPOSURES:Acute respiratory distress syndrome. MAIN OUTCOMES AND MEASURES: The primary outcome was ICU incidence of ARDS. Secondary outcomes included assessment of clinician recognition of ARDS, the application of ventilatory management, the use of adjunctive interventions in routine clinical practice, and clinical outcomes from ARDS. RESULTS: Of 29,144 patients admitted to participating ICUs, 3022 (10.4%) fulfilled ARDS criteria. Of these, 2377 patients developed ARDS in the first 48 hours and whose respiratory failure was managed with invasive mechanical ventilation. The period prevalence of mild ARDS was 30.0% (95% CI, 28.2%-31.9%); of moderate ARDS, 46.6% (95% CI, 44.5%-48.6%); and of severe ARDS, 23.4% (95% CI, 21.7%-25.2%). ARDS represented 0.42 cases per ICU bed over 4 weeks and represented 10.4% (95% CI, 10.0%-10.7%) of ICU admissions and 23.4% of patients requiring mechanical ventilation. Clinical recognition of ARDS ranged from 51.3% (95% CI, 47.5%-55.0%) in mild to 78.5% (95% CI, 74.8%-81.8%) in severe ARDS. Less than two-thirds of patients with ARDS received a tidal volume 8 of mL/kg or less of predicted body weight. Plateau pressure was measured in 40.1% (95% CI, 38.2-42.1), whereas 82.6% (95% CI, 81.0%-84.1%) received a positive end-expository pressure (PEEP) of less than 12 cm H2O. Prone positioning was used in 16.3% (95% CI, 13.7%-19.2%) of patients with severe ARDS. Clinician recognition of ARDS was associated with higher PEEP, greater use of neuromuscular blockade, and prone positioning. Hospital mortality was 34.9% (95% CI, 31.4%-38.5%) for those with mild, 40.3% (95% CI, 37.4%-43.3%) for those with moderate, and 46.1% (95% CI, 41.9%-50.4%) for those with severe ARDS. CONCLUSIONS AND RELEVANCE: Among ICUs in 50 countries, the period prevalence of ARDS was 10.4% of ICU admissions. This syndrome appeared to be underrecognized and undertreated and associated with a high mortality rate. These findings indicate the potential for improvement in the management of patients with ARDS

    Molecular control of δ-opioid receptor signalling

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    Opioids represent widely prescribed and abused medications, although their signal transduction mechanisms are not well understood. Here we present the 1.8Å high-resolution crystal structure of the human δ-opioid receptor (δ-OR), revealing the presence and fundamental role of a sodium ion mediating allosteric control of receptor functional selectivity and constitutive activity. The distinctive δ-OR sodium ion site architecture is centrally located in a polar interaction network in the 7-transmembrane bundle core, with the sodium ion stabilizing a reduced agonist affinity state, and thereby modulating signal transduction. Site-directed mutagenesis and functional studies reveal that changing the allosteric sodium site residue Asn131 to alanine or valine augments constitutive arrestin-ergic signaling. Asp95Ala, Asn310Ala, and Asn314Ala mutations transform classical δ-opioid antagonists like naltrindole into potent β-arrestin-biased agonists. The data establish the molecular basis for allosteric sodium ion control in opioid signaling, revealing that sodium-coordinating residues act as “efficacy-switches” at a prototypic G protein-coupled receptor

    PTF10fqs: A Luminous Red Nova in the Spiral Galaxy Messier 99

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    The Palomar Transient Factory (PTF) is systematically charting the optical transient and variable sky. A primary science driver of PTF is building a complete inventory of transients in the local Universe (distance less than 200 Mpc). Here, we report the discovery of PTF10fqs, a transient in the luminosity "gap" between novae and supernovae. Located on a spiral arm of Messier 99, PTF 10fqs has a peak luminosity of Mr = -12.3, red color (g-r = 1.0) and is slowly evolving (decayed by 1 mag in 68 days). It has a spectrum dominated by intermediate-width H (930 km/s) and narrow calcium emission lines. The explosion signature (the light curve and spectra) is overall similar to thatof M85OT2006-1, SN2008S, and NGC300OT. The origin of these events is shrouded in mystery and controversy (and in some cases, in dust). PTF10fqs shows some evidence of a broad feature (around 8600A) that may suggest very large velocities (10,000 km/s) in this explosion. Ongoing surveys can be expected to find a few such events per year. Sensitive spectroscopy, infrared monitoring and statistics (e.g. disk versus bulge) will eventually make it possible for astronomers to unravel the nature of these mysterious explosions.Comment: 12 pages, 12 figures, Replaced with published versio
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