70 research outputs found
Evaluation by an Aeronautic Dentist on the Adverse Effects of a Six-Week Period of Microgravity on the Oral Cavity
Objective. HDT bed rest condition is a simulated microgravity condition in which subject lies on bed inclined −6 degree feet up. To determine the influence of a simulated microgravity (HDT bed rest) on oral cavity, 10 healthy male volunteers were studied before, during, just after, and after 6 weeks of the simulated microgravity condition of −6° head-down-tilt (HDT) bed rest. Materials and Methods. Facial nerve function, facial sensation, chemosensory system, salivary biomarkers were measured. Results. Lactate dehydrogenase, MIP 1 alpha, malonaldehyde, 8-hydroxydeoxyguanosine, and thiocyanate were found to increase significantly, while flow rate, sodium, potassium, calcium, phosphate, protein, amylase activity, vitamin E and C, and mouth opening were decreased in simulation environments in contradiction to normal. The threshold for monosodium glutamate (MSG) and capsaicin increased during microgravity as compared to normal conditions. Moderate pain of teeth, facial oedema, mild pain, loss of sensation of pain and temperature, decreased tongue, and mandibular movement in simulation microgravity environments were observed. Conclusions. These results suggest that reversible effect of microgravity is oedema of face, change in taste, abnormal expression of face, teeth pain, and xerostomia. Further study will be required on large scale on long-term effects of microgravity on oral cavity to prevent the adverse effects
The EDIBLES Survey. VII. A survey of C2 and C3 in interstellar clouds
We carried out a sensitive survey of C and C using the EDIBLES data
set. We also expanded our searches to C, C, and CC
isotopologue in the most molecule-rich sightlines.
We fit synthetic spectra generated following a physical excitation model to
the C (2-0) Phillips band to obtain the C column density () as well
as the kinetic temperature () and number density () of the
host cloud. The C molecule was measured through its
(000-000) electronic origin band system. We simulated the excitation of this
band with a double-temperature Boltzmann distribution.
We present the largest combined survey of C and C to date in which
the individual transitions can be resolved. In total we detected C in 51
velocity components along 40 sightlines, and C in 31 velocity components
along 27 sightlines. The two molecules are detected in the same velocity
components. We find a very good correlation between (C) and (C)
with Pearson and an average (C)/(C) ratio of
15.51.4. A comparison with the behaviour of the C DIBs shows that
there are no clear differences among sightlines with and without detection of
C and C. This is in direct contrast to the better-studied non-C
DIBs who have reduced strengths in molecule-rich environments. We also identify
for the first time the (2), (3), and (4) transitions of the
CC (2-0) Phillips band in a stacked average spectrum, and
estimate the isotopic ratio of carbon C/C as 798. Our search
for the C and C optical bands was unsuccessful.Comment: 31 pages, 23 figures. To appear in A&
The ESO Diffuse Interstellar Bands Large Exploration Survey EDIBLES: I. Project description, survey sample and quality assessment
The carriers of the diffuse interstellar bands (DIBs) are largely unidentified molecules ubiquitously present in the interstellar medium (ISM). After decades of study, two strong and possibly three weak near-infrared DIBs have recently been attributed to the C+ 60 fullerene based on observational and laboratory measurements. There is great promise for the identification of the over 400 other known DIBs, as this result could provide chemical hints towards other possible carriers. In an effort to systematically study the properties of the DIB carriers, we have initiated a new large-scale observational survey: the ESO Diffuse Interstellar Bands Large Exploration Survey (EDIBLES). The main objective is to build on and extend existing DIB surveys to make a major step forward in characterising the physical and chemical conditions for a statistically significant sample of interstellar lines-of-sight, with the goal to reverse-engineer key molecular properties of the DIB carriers. EDIBLES is a filler Large Programme using the Ultraviolet and Visual Echelle Spectrograph at the Very Large Telescope at Paranal, Chile. It is designed to provide an observationally unbiased view of the presence and behaviour of the DIBs towards early-spectraltype stars whose lines-of-sight probe the diffuse-to-translucent ISM. Such a complete dataset will provide a deep census of the atomic and molecular content, physical conditions, chemical abundances and elemental depletion levels for each sightline. Achieving these goals requires a homogeneous set of high-quality data in terms of resolution (R ~ 70 000 – 100 000), sensitivity (S/N up to 1000 per resolution element), and spectral coverage (305–1042 nm), as well as a large sample size (100+ sightlines). In this first paper the goals, objectives and methodology of the EDIBLES programme are described and an initial assessment of the data is provided
Reaction:Surviving on the Moon, Mars, and Asteroids
Prof. Foing is an advisor to the director general of the European Space Agency (ESA), a space astrophysicist at the European Space Research & Technology Centre (ESTEC), executive director of the International Lunar Exploration Working Group (ILEWG), and research professor at Vrije Universiteit Amsterdam and Florida Tech. He was chief scientist, chairman of the ESTEC staff association, and lead scientist for the ESA SMART-1 mission to the Moon. He is co-investigator of ESA missions SOHO, COROT, Mars Express, ExoMars, and EXPOSE experiments (FOTON capsules and International Space Station). He is manager of ILEWG ExoGeoLab and EuroMoonMars field simulations in extreme terrestrial analogs. Prof. Foing is an advisor to the director general of the European Space Agency (ESA), a space astrophysicist at the European Space Research & Technology Centre (ESTEC), executive director of the International Lunar Exploration Working Group (ILEWG), and research professor at Vrije Universiteit Amsterdam and Florida Tech. He was chief scientist, chairman of the ESTEC staff association, and lead scientist for the ESA SMART-1 mission to the Moon. He is co-investigator of ESA missions SOHO, COROT, Mars Express, ExoMars, and EXPOSE experiments (FOTON capsules and International Space Station. He is manager of ILEWG ExoGeoLab and EuroMoonMars field simulations in extreme terrestrial analogs
Multitechnique characterization of secondary minerals near HI-SEAS, Hawaii, as Martian subsurface analogues
Abstract Secondary minerals in lava tubes on Earth provide valuable insight into subsurface processes and the preservation of biosignatures on Mars. Inside lava tubes near the Hawaii-Space Exploration and Analog Simulation (HI-SEAS) habitat on the northeast flank of Mauna Loa, Hawaii, a variety of secondary deposits with distinct morphologies were observed consisting of mainly sodium sulphate powders, gypsum crystalline crusts, and small coralloid speleothems that comprise opal and calcite layers. These secondary deposits formed as a result of hydrological processes shortly after the formation and cooling of the lava tubes and are preserved over long periods of time in relatively dry conditions. The coralloid speleothem layers are likely related to wet and dry periods in which opal and calcite precipitates in cycles. Potential biosignatures seem to have been preserved in the form of porous stromatolite-like layers within the coralloid speleothems. Similar secondary deposits and lava tubes have been observed abundantly on the Martian surface suggesting similar formation mechanisms compared to this study. The origin of secondary minerals from tholeiitic basalts together with potential evidence for microbial processes make the lava tubes near HI-SEAS a relevant analog for Martian surface and subsurface environments
Geometrical Analysis of AMIE/Smart-1 Images and Applications to Photometric Studies of the Lunar Surface
International audienc
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