10 research outputs found

    First optical detection of atomic deuterium in the upper atmosphere from Spacelab 1

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    International audienceMeasurements of the deuterium-to-hydrogen ratios (D/H) in the fields of meteorology1,2, tropospheric3,4 and stratospheric chemistry5,6, planetology7,8 and cosmogony8,9 have previously been performed on molecules in which one hydrogen atom is replaced by one deuterium atom. We report here the first detection of isolated deuterium atoms in the Earth's upper atmosphere through their resonantly scattered Lyman-α emission. An atmospheric deuterium emission of 330 R (1 R=106 photons cm−2 s−1) is observed for a tangent altitude of 110 km during Spacelab 1 mission launched on 28 November 1983. The (D/H) ratio of 3×10−4 is slightly enriched over the seawater value of 1.6×10−4

    SPICAM IR acousto-optic spectrometer experiment on Mars Express

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    The SPICAM IR spectrometer on Mars Express mission (1.0–1.7 ?m, spectral resolution 0.5–1.2 nm) is dedicated primarily to nadir measurements of H2O abundance. It is one of two channels of SPICAM UV-IR instrument. In this spectrometer we applied for the first time in planetary research the technology of an acousto-optic tunable filter (AOTF) that allowed unprecedented mass reduction for such an instrument: 0.75 kg. SPICAM IR is a point nadir-looking spectrometer with sequential scanning of the spectrum by the AOTF. Sun occultations are performed with a help of dedicated solar port. We describe instrumentation, calibrations, and the modes of operations of the device and discuss its in-flight performances. A brief overview of the scientific measurements includes water vapor measurements and the mapping of intensity of the O2(a1? g ) emission at 1.27 ?m, described in detail in separate papers. Measurements in reflected solar light allow clear detection of H2O and CO2 ices on the surface or in the atmosphere of Mars. We discuss solar occultation measurements by SPICAM and present resulting vertical profiles of aerosol optical depth

    Exploration of Mars in SPICAM-IR experiment onboard the Mars-Express spacecraft: 1. Acousto-optic spectrometer SPICAM-IR

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    International audienceThe acousto-optic spectrometer of the near infrared range, which is a part of the spectrometer SPICAM onboard the Mars-Express spacecraft, began to operate in the orbit of Mars in January 2004. In the SPICAM experiment, a spectrometer on the basis of an acousto-optic filter was used for the first time to investigate other planets. During one and a half years of operation, the IR channel of SPICAM obtained more than half a million spectra in the 1-1.7 ÎŒm range with a resolving power of more than 1500 in different modes of observation: limb, nadir, and solar eclipses. The main goal of the experiment is to study the content of water vapor in the Martian atmosphere by measuring the absorption spectrum in the 1.38 ÎŒm band. Characteristics of the instrument (high spectral resolution and signal-to-noise ratio) allow one to solve a number of additional scientific problems including the study of ozone distribution by emission of singlet oxygen (O2 1Δg), detection of the water and carbonic dioxide ices, and also the study of the vertical distribution and optical characteristics of aerosol in the Martian atmosphere. We present a description of the instrument, the results of its ground and in-flight calibrations, and a brief survey of the basic scientific results obtained by the SPICAM spectrometer during a year-and-half of operation

    The Energetic Particle Telescope: First Results

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    The Energetic Particle Telescope (EPT) is a new compact and modular ionizing particle spectrometer that was launched on 7 May 2013 to a LEO polar orbit at an altitude of 820 km onboard the ESA satellite PROBA-V. First results show electron, proton and helium ion fluxes in the South Atlantic Anomaly (SAA) and at high latitudes, with high flux increases during SEP (Solar Energetic Particles) events and geomagnetic storms. These observations help to improve the understanding of generation and loss processes associated to the Van Allen radiation belt

    A warm layer in Venus' cryosphere and high-altitude measurements of HF, HCl, H[SUB]2[/SUB]O and HDO

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    Venus has thick clouds of H[SUB]2[/SUB]SO[SUB]4[/SUB] aerosol particles extending from altitudes of 40 to 60km. The 60-100km region (the mesosphere) is a transition region between the 4day retrograde superrotation at the top of the thick clouds and the solar-antisolar circulation in the thermosphere (above 100km), which has upwelling over the subsolar point and transport to the nightside. The mesosphere has a light haze of variable optical thickness, with CO, SO[SUB]2[/SUB], HCl, HF, H[SUB]2[/SUB]O and HDO as the most important minor gaseous constituents, but the vertical distribution of the haze and molecules is poorly known because previous descent probes began their measurements at or below 60km. Here we report the detection of an extensive layer of warm air at altitudes 90-120km on the night side that we interpret as the result of adiabatic heating during air subsidence. Such a strong temperature inversion was not expected, because the night side of Venus was otherwise so cold that it was named the `cryosphere' above 100km. We also measured the mesospheric distributions of HF, HCl, H[SUB]2[/SUB]O and HDO. HCl is less abundant than reported 40years ago. HDO/H[SUB]2[/SUB]O is enhanced by a factor of ~2.5 with respect to the lower atmosphere, and there is a general depletion of H[SUB]2[/SUB]O around 80-90km for which we have no explanation

    Congruence between nurses' and patients' assessment of postoperative pain: a literature review

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    Postoperative pain remains poorly managed for many patients. Effective pain management begins with accurate pain assessment, with patient self-reporting considered the most accurate measure of pain. This literature review aimed to identify how congruent nurses' assessments of pain were with patients' self-reporting. A search identified six observational studies and one quasi-experimental study that met the inclusion criteria. The findings from these studies were summarised under two themes: nurses' underestimation of patients' pain and nurses' knowledge and understanding of pain assessment. Some nurses' pain management knowledge was deemed inadequate, with evidence of negative attitudes towards managing pain in certain groups of patients. Educational interventions have so far had limited impact on correcting the ethical and professional problem of inadequate pain relief in many patients postoperatively. Randomised controlled trials are required to identify effective education interventions that can contribute to ending this avoidable suffering
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