Publications by authors named "Altobelli N"

Article Synopsis
  • - There is a debate about whether Saturn's main rings are old, formed shortly after the planet, or younger, created during the Late Heavy Bombardment.
  • - The rings consist mainly of water-ice but have up to 2% non-icy materials caused by micrometeoroid impacts.
  • - Cassini's Cosmic Dust Analyzer measured the micrometeoroid flux, finding it mostly from the Kuiper belt, leading to an estimated ring exposure time of less than 100 to 400 million years, supporting the idea that the rings formed relatively recently.
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The international Rosetta mission was launched in 2004 and consists of the orbiter spacecraft Rosetta and the lander Philae. The aim of the mission is to map the comet 67P/Churyumov-Gerasimenko by remote sensing, and to examine its environment and its evolution in the inner Solar System. Rosetta was the first spacecraft to rendezvous with and orbit a comet, accompanying it as it passes through the inner Solar System, and to deploy a lander, Philae, and perform science on the comet's surface.

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The cometary dust particle instrument COSIMA (COmetary Secondary Ion Mass Analyser) onboard ESA's Rosetta mission has collected about 31 000 dust particles in the inner coma of comet 67P/Churyumov-Gerasimenko since August 2014. The particles are identified by optical microscope imaging and analysed by time-of-flight secondary ion mass spectrometry. After dust particle collection by low speed impact on metal targets, the collected particle morphology points towards four families of cometary dust particles.

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Interstellar dust (ISD) is the condensed phase of the interstellar medium. In situ data from the Cosmic Dust Analyzer on board the Cassini spacecraft reveal that the Saturnian system is passed by ISD grains from our immediate interstellar neighborhood, the local interstellar cloud. We determine the mass distribution of 36 interstellar grains, their elemental composition, and a lower limit for the ISD flux at Saturn.

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Detection of sodium-salt-rich ice grains emitted from the plume of the Saturnian moon Enceladus suggests that the grains formed as frozen droplets from a liquid water reservoir that is, or has been, in contact with rock. Gravitational field measurements suggest a regional south polar subsurface ocean of about 10 kilometres thickness located beneath an ice crust 30 to 40 kilometres thick. These findings imply rock-water interactions in regions surrounding the core of Enceladus.

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Critical measurements for understanding accretion and the dust/gas ratio in the solar nebula, where planets were forming 4.5 billion years ago, are being obtained by the GIADA (Grain Impact Analyser and Dust Accumulator) experiment on the European Space Agency's Rosetta spacecraft orbiting comet 67P/Churyumov-Gerasimenko. Between 3.

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Tracheostomy tubes are used to administer positive-pressure ventilation, to provide a patent airway, and to provide access to the lower respiratory tract for airway clearance. They are available in a variety of sizes and styles from several manufacturers. The dimensions of tracheostomy tubes are given by their inner diameter, outer diameter, length, and curvature.

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Background: Noninvasive positive-pressure ventilation (NPPV) has been shown to be effective in select patients enrolled in clinical trials. However, few data are available on the use of NPPV as routine standard medical care for patients with respiratory failure outside of controlled trials.

Measurements And Main Results: All patients receiving NPPV for a 1-yr period for acute or acute on chronic respiratory failure who did not select do not intubate/resuscitate status were evaluated.

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Objective: To determine the outcome from the use of noninvasive positive pressure ventilation (NPPV) in "do-not-intubate" (DNI) patients in acute respiratory failure.

Design: Prospective observational study.

Setting: University-affiliated large medical center.

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