Defects on a pyrite(100) surface produce chemical evolution of glycine under inert conditions : experimental and theoretical approaches

Acknowledgements This work has been supported by the MINECO project ESP2017-89053. The Instituto Nacional de Tecnica Aeroespacial supported the work performed at CAB. EER is thankful to Javier Martin-Torres, Alfonso Hernandez-Laguna and C. M. Pradier for their support and suggestions. This Project has been partially funded by the Spanish State Research Agency (AEI) Project No. MDM-2017-0737 Unidad de Excelencia ‘‘Marıa de Maeztu’’-Centro de Astrobiologıa (CSIC-INTA).Peer reviewedPublisher PD

Double-balloon catheter for induction of labour in women with a previous cesarean section, could it be the best choice?

INTRODUCTION: We analysed the efficacy and safety of double-balloon catheter for cervical ripening in women with a previous cesarean section and which were the most important variables associated with an increased risk of repeated cesarean delivery. MATERIALS AND METHODS: We designed an observational retrospective study of 418 women with unfavourable cervices (Bishop Score <5), a prior cesarean delivery, and induction of labour with a double-balloon catheter. Baseline maternal data and perinatal outcomes were recorded for a descriptive, bivariate, and multivariate analysis. A p value <0.05 was considered statistically significant. RESULTS: Most women improved their initial Bishop Score (89.5%) although only a 20.8% of them went into spontaneous active labour. Finally, 51.4% of the women achieved a vaginal delivery. Five cases of intrapartum uterine rupture (1.2%) occurred. After multivariate analysis, main risk factors for repeated cesarean section were dystocia in the previous pregnancy (OR 1.744; CI 95% 1.066–2.846), the absence of previous vaginal delivery (OR 2.590; CI 95% 1.066–6.290), suspected fetal macrosomia (OR 2.410; CI 95% 0.959–6.054), and duration of oxytocin induction period (OR 1.005; CI 95% 1.004–1.006). The area under the curve was 0.789 (p < 0.001). CONCLUSIONS: Double-balloon catheter seems to be safe and effective for cervical ripening in women with a previous cesarean delivery and unfavourable cervix. In our study, most women could have a vaginal delivery in spite of their risk factors for cesarean delivery. A multivariate model based on some clinical variables has moderate predictive value for intrapartum cesarean section

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

UV irradiation study of a tripeptide isolated in an argon matrix: A tautomerism process evidenced by infrared and X-ray photoemission spectroscopies.

International audienceMatrix isolation is a powerful tool for studying photochemical processes occurring in isolated molecules. In this way, we characterized the chemical modifications occurring within a tri peptide molecule, IGF, when exposed to the influence of Ultraviolet (UV) irradiation. This paper first describes the successful formation of the tripeptide (IGF) argon matrix under vacuum conditions, followed by the in situ UV irradiation and characterization of the molecular matrix reactivity after UV-irradiation. These studies have been performed by combining two complementary spectroscopic techniques, Fourier-Transform Reflexion Absorption Spectroscopy (FT-IRRAS) and X-ray Photoelectron Spectroscopy (XPS). The IR spectra of the isolated peptide-matrix, before and after UV irradiation, revealed significant differences that could be associated either to a partial deprotonation of the molecule or to a tautomeric conversion of some amide bonds to imide ones on some peptide molecules. XPS analyses undoubtedly confirmed the second hypothesis; the combination of IRRAS and XPS results provide evidence that UV irradiation of peptides induces a chemical reaction, namely a shift of the double bond, meaning partial conversion from amide tautomer into an imidic acid tautomer

CO2 adsorption capacities of amine-functionalized microporous silica nanoparticles

Efforts on CO2 capture have intensified as climate change compromises ecosystems and biodiversity. Therefore, it is crucial to develop different methods for CO2 sequestration to improve solid sorbent capabilities (NPs). To this end, the surface of 200-nm silica nanoparticles (SiO2NPs) was covalently anchored with aminated ligands, 3-aminopropyltriethoxysilane (APTES), poly(amidoamine) dendrimers (PAMAM) and a short peptide comprising two lysine units, aiming for CO2 adsorption over a wide range of pressures. Our goal was to explore the influence of functional chemical groups (attached to the SiO2NPs) on CO2 sequestration. The observed results showed that at low and high CO2 gas pressure conditions, typical APTES functionalized SiO2Np surpassed the CO2 adsorption capacities of dendritic and peptide-based nanoparticles bearing amine-polymer functionalities, a remarkable effect that was investigated in this work. In addition, a convenient and facile method to decorate and quantify SiO2 nanoparticles with PAMAM and a short peptide is reported.This work has been supported by MINECO grants PID2019-104205GB-C21 and PID2019-107442RB-C32) and has been partially funded by the Spanish State Research Agency (AEI) Project No. MDM-2017-0737 Unidad de Excelencia “María de Maeztu”-Centro de Astrobiología (INTA-CSIC) and by PCTI 2013-2017 from the Principado de Asturias and ERDF through projects RTI2018-100832-B-I00 and IDI/2018/000233. E. C. D: Talent Attraction Postdoctoral Fellowship from CAM, reference: 2018-T2/TIC-10616. The authors also thank Maite Sampedro for her help during IR measurements.Peer reviewe

Highly dense nickel hydroxide nanoparticles catalyst electrodeposited from a novel Ni(II) paddle–wheel complex

International audienc

Future space experiment platforms for astrobiology and astrochemistry research

Space experiments are a technically challenging but a scientifically important part of astrobiology and astrochemistry research. The International Space Station (ISS) is an excellent example of a highly successful and long-lasting research platform for experiments in space, that has provided a wealth of scientific data over the last two decades. However, future space platforms present new opportunities to conduct experiments with the potential to address key topics in astrobiology and astrochemistry. In this perspective, the European Space Agency (ESA) Topical Team Astrobiology and Astrochemistry (with feedback from the wider scientific community) identifies a number of key topics and summarizes the 2021 “ESA SciSpacE Science Community White Paper” for astrobiology and astrochemistry. We highlight recommendations for the development and implementation of future experiments, discuss types of in situ measurements, experimental parameters, exposure scenarios and orbits, and identify knowledge gaps and how to advance scientific utilization of future space-exposure platforms that are either currently under development or in an advanced planning stage. In addition to the ISS, these platforms include CubeSats and SmallSats, as well as larger platforms such as the Lunar Orbital Gateway. We also provide an outlook for in situ experiments on the Moon and Mars, and welcome new possibilities to support the search for exoplanets and potential biosignatures within and beyond our solar system