Protocols to determine cytotoxicity of intraocular medical devices should be revised to assure safety. Acute toxic events should be reported to health authorities and scientific media.
a b s t r a c tThe future ExoMars rover mission (ESA/Roscosmos), to be launched in 2018, will investigate the habitability of the Martian surface and near subsurface, and search for traces of past life in the form of textural biosignatures and organic molecules. In support of this mission, a selection of relevant Mars analogue materials has been characterised and stored in the International Space Analogue Rockstore (ISAR), hosted in Orléans, France. Two ISAR samples were analysed by prototypes of the ExoMars rover instruments used for petrographic study. The objective was to determine whether a full interpretation of the rocks could be achieved on the basis of the data obtained by the ExoMars visible-IR imager and spectrometer (MicrOmega), the close-up imager (CLUPI), the drill infrared spectrometer (Ma_Miss) and the Raman spectrometer (RLS), first separately then in their entirety. In order to not influence the initial instrumental interpretation, the samples were sent to the different teams without any additional
This work aims to evaluate whether the multi-point analysis the ExoMars Raman Laser Spectrometer (RLS) will perform on powdered samples could serve to classify ultramafic rocks on Mars. To do so, the RLS ExoMars Simulator was used to study terrestrial analogues of Martian peridotites and pyroxenites by applying the operational constraints of the Raman spectrometer onboard the Rosalind Franklin rover. Besides qualitative analysis, RLS-dedicated calibration curves have been built to estimate the relative content of olivine and pyroxenes in the samples. These semi-quantitative results, combined with a rough estimate of the concentration ratio between clino- and ortho-pyroxene mineral phases, were used to classify the terrestrial analogues. XRD data were finally employed as reference to validate Raman results. As this preliminary work suggests, ultramafic rocks on Mars could be effectively classified through the chemometric analysis of RLS data sets. After optimization, the proposed chemometric tools could be applied to the study of the volcanic geological areas detected at the ExoMars landing site (Oxia Planum), whose mineralogical composition and geological evolution have not been fully understood.
Guano is a typical deposit found in caves derived from the excretions of bats and in minor cases of birds. These organic deposits decompose and form a series of acid fluids and gases that can interact with the minerals, sediments, and rocks present in the cave. Over sixty phosphates are known and described from caves, but guano decay also often leads to the formation of nitrates and sulfates. In this study twenty-two European caves were investigated for their guano-related secondary minerals. Using various analytical techniques, seventeen phosphates, along with one sulfate (gypsum), were recognized as secondary products of guano decay. Among those minerals, some are very rare and result from the interaction of guano leachates with clays, fluvial deposits, or pyrite. Some of these minerals are even found only in the studied caves (spheniscidite, robertsite). The most common minerals belong to the apatite group. The common mineral association present in fresh decaying guano is brushiteardealite-gypsum, minerals that usually are not present in older deposits because of their higher solubility. Most minerals are in hydrated form because of the wet cave environment; however, some specific dry conditions may favor the presence of dehydrated minerals, such as berlinite, formed during guano combustion. Investigation on the acidity of guano piles shows pH values as low as 3.5 with an increase of acidity with age and depth. Finally, cave guano deposits should be better studied in the future because of their role in paleoenvironmental and paleoclimatic reconstructions and because it is important to better understand the origin of guano-related minerals, especially the phosphates and sulfates. Among all of the caves studied, Corona 'e sa Craba (Italy) and Domica-Baradla Cave (Slovakia-Hungary) are considered to be outstanding sites with respect to their phosphate mineralogy. secondary cave minerals, phosphates, minerogenesis, limestone caves, bat guano
Raman and laser‐induced breakdown spectroscopy (LIBS) spectroscopies will play an important role in planetary exploration missions in the following years, not only with Raman instruments like Raman laser spectrometer on board of Rosalid Franklin Rover or scanning habitable environments with Raman and luminescence for organics and chemicals on board Mars2020 Rover but also with combined instruments such as SuperCam. These techniques will be part of the upcoming planetary exploration missions because they can provide complementary information from the analysed sample while potentially sharing hardware components, maximizing the scientific return of the samples while limiting mass. In this framework, this study seeks to test the feasibility of combining several univariate and multivariate analysis techniques with data fusion techniques of different instruments (532 and 785 nm Raman and LIBS) to evaluate the improvements in the quantitative classification of samples in binary mixtures. We prepared two‐component mixtures that are potentially relevant in planetary exploration missions, using two different sulfates and a chloride. A more accurate classification of the samples is possible through a univariate analysis that combines the calculated concentration indicators for Raman and LIBS. On the other hand, multivariate analysis was run on Raman, LIBS, and Raman + LIBS low‐level fused data sets. The results showed a better improvement when fusing LIBS and Raman when compared with the redundant fusion but not a systematic improvement when compared with individual sets. We demonstrate that a quantification of the mineral abundances in binary mixtures can be obtained from Raman and LIBS data using univariate and multivariate analysis techniques, being the latter remarkably better, moving from performances of classification, in the whole range of concentrations, that could be over the 10% to values under 3.5%. Furthermore, the fusion of data coming from these techniques improves the classification limit with respect to the individual techniques. Thus, besides the (evident) hardware convenience of combining LIBS with 532‐nm Raman, there could be analytical advantages as well.
The outcrop of ''Los Azulejos" is visible at the interior of the Cañ adas Caldera in Tenerife Island (Spain). It exhibits a great variety of alteration processes that could be considered as terrestrial analogue for several geological processes on Mars. This outcrop is particularly interesting due to the content of clays, zeolite, iron oxides, and sulfates corresponding to a hydrothermal alteration catalogued as ''Azulejos" type alteration. A detailed analysis by portable and laboratory Raman systems as well as other different techniques such as X-ray diffraction (XRD) and Mö ssbauer spectroscopy has been carried out (using twin-instruments from Martian lander missions: Mö ssbauer spectrometer MIMOS-II from the NASA-MER mission of 2001 and the XRD diffractometer from the NASA-MSL Curiosity mission of 2012). The mineral identification presents the following mineral species: magnetite, goethite, hematite, anatase, rutile, quartz, gregoryite, sulfate (thenardite and hexahydrite), diopside, feldspar, analcime, kaolinite and muscovite. Moreover, the in-situ Raman and MicroRaman measurements have been performed in order to compare the capabilities of the portable system specially focused for the next ESA Exo-Mars mission. The mineral detection confirms the sub-aerial alteration on the surface and the hydrothermal processes by the volcanic fluid circulations in the fresh part. Therefore, the secondary more abundant mineralization acts as the color agent of the rocks. Thus, the zeolite-illite group is the responsible for the bluish coloration, as well as the feldspars and carbonates for the whitish and the iron oxide for the redish parts. The XRD system was capable to detect a minor proportion of pyroxene, which is not visible by Raman and Mö ssbauer spectroscopy due to the ''Azulejos" alteration of the parent material on the outcrop. On the other hand, Mö ssbauer spectroscopy was capable of detecting different types of iron-oxides (Fe 3+/2+ -oxide phases). These analyses emphasize the strength of the different techniques and the working synergy of the three different techniques together for planetary space missions.
We evaluate what will be the effectiveness of the ExoMars Raman Laser Spectrometer (RLS) to determine the degree of serpentinization of olivine-rich units on Mars. We selected terrestrial analogues of martian ultramafic rocks from the Leka Ophiolite Complex (LOC) and analyzed them with both laboratory and flight-like analytical instruments. We first studied the mineralogical composition of the samples (mostly olivine and serpentine) with state-of-the-art diffractometric (XRD) and spectroscopic (Raman, NIR) laboratory systems. We compared these results with those obtained using our RLS ExoMars Simulator. Our work shows that the RLS ExoMars Simulator successfully identified all major phases. Moreover, when emulating the automatic operating mode of the flight instrument, the RLS ExoMars simulator also detected several minor compounds (pyroxene and brucite), some of which were not observed by NIR and XRD (e.g. calcite). Thereafter, we produced RLS-dedicated calibration curves (R 2 between 0.9993 and 0.9995 with an uncertainty between ±3.0% and ±5.2% with a confidence interval of 95%) to estimate the relative content of olivine and serpentine in the samples. Our results show that RLS can be very effective to identify serpentine, a scientific target of primary importance for the potential detection of biosignatures on Mars-the main objective of the ExoMars rover mission.
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