33 research outputs found
Raman-IR spectroscopic, and XRD analysis of selected samples from Fogo Island, Cabo Verde: Implications for ancient Martian volcanology
Several space missions from NASA, and ESA have visited and will land on Mars in the search for life. The last mission to arrive was the Mars 2020 Perseverance rover on 18 February 2021. The next mission to Mars will be ExoMars Rosalind Franklin rover, expected to touch down sometime after 2028. Both Mars2020 and ExoMars are equipped with Raman spectroscopic systems: SuperCam and SHERLOC on Perseverance, and Raman Laser Spectrometer (RLS) on Rosalind Franklin (RF). These instruments will be tasked with identifying rocks, minerals, and potential organic biosignatures on the Martian surface. There are many challenges associated with the qualitative and quantitative analysis of resulting data received from current missions on Mars. It is our belief that studies of new terrestrial Martian analogues can help to overcome these challenges. Here, we introduce Chã das Caldeiras Outcrop, Fogo Island, Cabo Verde as a new volcanic terrestrial analog for Mars. We sampled several areas of relevance in Chã das Caldeiras and conducted a complete band analysis of Raman spectra for targets from this site. Additional analyses included ATR-FTIR and XRD. We detected several pyroxene types (augite and diopside) and plagioclase feldspar species (orthoclase, bytownite, sanidine, albite, and anorthite), olivine (forsterite), oxides (magnetite), and leucite. The alteration and secondary minerals detected were carbonates (calcite and dolomite), oxides (goethite, anatase, and hematite), spinel (chromite), phosphate (apatite), various clays, and zeolites (chabazite and muscovite and analcime). We present the Chã das Caldeiras site as a possible new volcanic analogue for Mars given: 1) the similarities to other volcanic places in the Canary Islands; 2) the exclusive geological evolution that is only present in the volcanic emplacement from the Macaronecia-group; 3) the pristine quality of the samples from the outcrop as well as the alteration volcanic minerals.MGD at CRESS, York University, is especially thankful for the financial support provided by the Natural Sciences and Engineering Research Council of Canada (NSERC), the Ontario Centre of Excellence (OCE), and the Canadian Space Agency. GLR, MV, FR, and JAM would like to acknowledge the financial support provided for this project by the European Research Council in the H2020- COMPET-2015 Programme (grant 687302) and the Ministry of Economy and Competitiveness (MINECO, grant PID2019-107442RB-C31/AEI/10.13039/501100011033). EAC thanks the Canada Foundation for Innovation, Research Manitoba, NSERC, the Canadian Space Agency, and the University of Winnipeg for supporting this study. Finally, EAL and MK want to thank Pebbles for her logistical support.Peer reviewe
VizieR Online Data Catalog: HAT-P-3b and TrES-3b light curves and Mid-times (Ricci+, 2017)
Tables contain the light curves and the calculated Mid-times. (15 data files)
Whole-genome sequencing reveals host factors underlying critical COVID-19
Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2–4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease
Rare predicted loss-of-function variants of type I IFN immunity genes are associated with life-threatening COVID-19
Background: We previously reported that impaired type I IFN activity, due to inborn errors of TLR3- and TLR7-dependent type I interferon (IFN) immunity or to autoantibodies against type I IFN, account for 15–20% of cases of life-threatening COVID-19 in unvaccinated patients. Therefore, the determinants of life-threatening COVID-19 remain to be identified in ~ 80% of cases. Methods: We report here a genome-wide rare variant burden association analysis in 3269 unvaccinated patients with life-threatening COVID-19, and 1373 unvaccinated SARS-CoV-2-infected individuals without pneumonia. Among the 928 patients tested for autoantibodies against type I IFN, a quarter (234) were positive and were excluded. Results: No gene reached genome-wide significance. Under a recessive model, the most significant gene with at-risk variants was TLR7, with an OR of 27.68 (95%CI 1.5–528.7, P = 1.1 × 10−4) for biochemically loss-of-function (bLOF) variants. We replicated the enrichment in rare predicted LOF (pLOF) variants at 13 influenza susceptibility loci involved in TLR3-dependent type I IFN immunity (OR = 3.70[95%CI 1.3–8.2], P = 2.1 × 10−4). This enrichment was further strengthened by (1) adding the recently reported TYK2 and TLR7 COVID-19 loci, particularly under a recessive model (OR = 19.65[95%CI 2.1–2635.4], P = 3.4 × 10−3), and (2) considering as pLOF branchpoint variants with potentially strong impacts on splicing among the 15 loci (OR = 4.40[9%CI 2.3–8.4], P = 7.7 × 10−8). Finally, the patients with pLOF/bLOF variants at these 15 loci were significantly younger (mean age [SD] = 43.3 [20.3] years) than the other patients (56.0 [17.3] years; P = 1.68 × 10−5). Conclusions: Rare variants of TLR3- and TLR7-dependent type I IFN immunity genes can underlie life-threatening COVID-19, particularly with recessive inheritance, in patients under 60 years old
SuperCam Calibration Targets: Design and Development
SuperCam is a highly integrated remote-sensing instrumental suite for NASA’s Mars 2020 mission. It consists of a co-aligned combination of Laser-Induced Breakdown Spectroscopy (LIBS), Time-Resolved Raman and Luminescence (TRR/L), Visible and Infrared Spectroscopy (VISIR), together with sound recording (MIC) and high-magnification imaging techniques (RMI). They provide information on the mineralogy, geochemistry and mineral context around the Perseverance Rover.
The calibration of this complex suite is a major challenge. Not only does each technique require its own standards or references, their combination also introduces new requirements to obtain optimal scientific output. Elemental composition, molecular vibrational features, fluorescence, morphology and texture provide a full picture of the sample with spectral information that needs to be co-aligned, correlated, and individually calibrated.
The resulting hardware includes different kinds of targets, each one covering different needs of the instrument. Standards for imaging calibration, geological samples for mineral identification and chemometric calculations or spectral references to calibrate and evaluate the health of the instrument, are all included in the SuperCam Calibration Target (SCCT). The system also includes a specifically designed assembly in which the samples are mounted. This hardware allows the targets to survive the harsh environmental conditions of the launch, cruise, landing and operation on Mars during the whole mission. Here we summarize the design, development, integration, verification and functional testing of the SCCT. This work includes some key results obtained to verify the scientific outcome of the SuperCam system
Whole-genome sequencing reveals host factors underlying critical COVID-19
Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2,3,4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease
Systematic isotopic marking of polymeric components for in-situ space missions
In the last decades, together with the technological advances, the exploration of closer celestial bodies has experimented a high increasing, with a special relevance of the missions whose objective is the scientific search of life precursors. Since the birth of COSPAR (Committee on space research) in 1964, many advances have been achieved in terms of Planetary Protection, to avoid introducing terrestrial contamination in other systems, and/or come back with extraterrestrial contaminations in sample return missions. Many restrictive protocols are adopted by space missions to minimize the bacteriological, molecular and particle contaminations, and especially harder in scientific missions, where the risk of a false positive in an analysis due to terrestrial contamination is critical. These missions search for small quantities of organic material, and any trace of simple signals of C–H, C–O, C–C, C–N, etc. bonds are the target. Many of these signals are present in all the polymeric components used in a space vehicle, and any accidental or natural contamination could lead to a false positive detection of precursors of life. In this work, a new protected technology to avoid any doubt in these cases is proposed: the systematic isotopic marking of polymeric materials used in space missions. As proof of concept, polyethylene terephthalate (PET) polymers, with the same characteristics of the one used in the calibration target for the Raman Laser Spectrometer (RLS) in the ExoMars mission, were synthetized in three different ratios of deuterium marking: 0%, 35%, and 100%. In addition the calibration target of the SuperCam instrument of the Mars 2020 mission also includes a sample of PET. The polymeric characterization by Thermo-gravimetric analysis (TGA) and Differential scanning calorimetry (DSC) showed similar characteristics, in the range of commercial PET polymers. The same analytical techniques used for organic studies, on board of the ExoMars laboratory, were used for this study: Raman spectroscopy, and Gas chromatography with mass spectrometry (GC/MS). Results showed that both marked compositions could be unequivocally identified, due to the expected differences caused by the increasing of mass of the marked hydrogen atoms. The materials were subjected to the outgassing test, according to ECSS-Q-ST-70-02C standard, of mandatory compliance for every material used in a space mission following the European standards ECSS, to test the validity for space use. All materials, marked and unmarked, passed this test, and even a slight improvement in RML could be observed in the fully deuterium marked (100%) PET, probably caused by its higher weight, but further studies are needed to verify this trend.With funding from the Spanish government through the "MarÃa de Maeztu Unit of Excellence" accreditation (MDM-2017-0737
Biological activity of Pouteria sapota leaf extract on post-embryonic development of blowfly Chrysomya putoria (Wiedemann, 1818) (Calliphoridae)
Chemical insecticides have been the main way to control synanthropic flies of medical and veterinary importance; however, residuals of these products have become a factor impacting on the environment, as well as the potential toxicological that they may cause damage to humans and domestic animals. Phytochemical screening carried out with the aqueous crude extract of Pouteria sapota (Jacq.) H.E. Moore & Stearn, Sapotaceae, leaves showed that coumarins, reducing sugars, flavonoids and cyanogenic glycosides were its most abundant metabolites. This study evaluated the activity of the crude aqueous extract of this plant on the post-embryonic development of Chrysomya putoria. Larvae treated with 5, 10 and 25% extract showed a decrease in the pupal period and in the newly-hatched larvae to adult period when compared to the control groups. Larvae from the 25% extract group were the lightest (45.8 mg) when compared with the control group (46.5 mg). The larval and newly-hatched larvae to adult stages were more sensitive to the leaf extract from P. sapota (5%) and the treated flies showed the low viability (47.5 and 45.5% respectively). The results demonstrated that topic treatment with P. sapota could alter C. putoriapost embryonic development
Multi-filter transit observations of HAT-P-3b and TrES-3b with multiple Northern Hemisphere telescopes
We present a photometric follow-up of transiting exoplanets HAT-P-3b and TrES-3b, observed by using several optical and near-infrared filters, with four small-class telescopes (D = 36-152 cm) in the Northern Hemisphere. Two of the facilities present their first scientific results. New 10 HAT-P-3b light curves and new 26 TrES-3b light curves are reduced and combined by filter to improve the quality of the photometry. Combined light curves fitting is carried out independently by using two different analysis packages, allowing the corroboration of the orbital and physical parameters in the literature. Results find no differences in the relative radius with the observing filter. In particular, we report for HAT-P-3b a first estimation of the planet-to-star radius (Formula Presented) in the B band which is coherent with values found in the VRIz\ue2\u80\u99JH filters. Concerning TrES-3b, we derive a value for the orbital period of P = 1.3061862 \uc2\ub1 0.0000001 days which shows no linear variations over nine years of photometric observations