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Editorial: The blue frontier: cancer research meets the diversity of marine chemistry and biology, new challenges, and prospects
No full textInternational audienceEditorial on the Research TopicThe blue Frontier: cancer research meets the diversity of marine chemistry and biology, new challenges and prospects Marine ecosystems account for more than 80% of the planet's biodiversity (Dayanidhi et al., 2021). Despite their immense potential for health, they have been studied far less than terrestrial ecosystems for the discovery of innovative drugs. Nonetheless, 15 marine-derived drugs have already been approved for commercialization (https://www. marinepharmacology.org/approved), including eight anticancer drugs. This vast marine biodiversity, along with the intricate and unique adaptations that enable survival in challenging physical environments, serves as a rich source of inspiration for scientists, driving innovative concepts and biotechnological developments. Over the past decades, several exciting areas of research have emerged and benefited from translational exchanges between marine sciences and oncology. Some examples include the "One World-One Health Concept" for the study of the impact of human activities on marine species oncogenesis, transmissible cancers, and tumor suppressor mechanisms (Dujon et al., 2021). The deep sea environment offers a vast reservoir of microorganisms, fungi, and invertebrates, complemented by algae and phytoplankton thriving in upper sea levels. Together, these organisms produce an extensive variety of primary and secondary metabolites, many of which exhibit potential anticancer and/or immunomodulatory properties (Molinski et al., 2009). Beyond small molecules, marine organisms also synthesize a diversity of macromolecules with unique biological, physicochemical, and structural properties, holding potential for by-product valorization, offering positive outcomes for both marine science and oncology (Claverie et al., 2020). The articles within this Research Topic explore various aspects of these compelling translational connections (https://www.frontiersin.org/research-topics/58861/the-blue-frontier-cancerresearch-meets-the-diversity-of-marine-chemistry-and-biology-new-challenges-and-prosp ects/articles).</div
THE DETECTION OF A POTENTIAL BIOSIGNATURE BY THE PERSEVERANCE ROVER ON MARS
No full textInternational audienceThe Perseverance rover has explored and sampled igneous and sedimentary rocks in Jezero crater to characterize early Martian geological processes and habitability and search for biosignatures. Upon entering Neretva Vallis, Perseverance investigated a set of distinct mudstone and conglomerate outcrops. We report on measurements from these rocks and describe the discovery of a potential biosignature [1]
Multi-Scale Photogrammetric 3D Reconstruction of Apollo 17 Station 7
No full textInternational audienceThe Apollo 17 manned mission landed in the Taurus Littrow valley on the Moon in December 1972. During three days spent at the lunar surface, a total of 111 kg of well-documented rock and soil samples were collected from geologic waypoints and brought back to Earth [1, 2]. In a previous study, we used scanned photographs taken in situ with astronaut’s Hasselblad film cameras to reconstruct 3D models of boulders using Structurefrom-Motion photogrammetry [3, 4]. In addition to the 3D reconstruction of the boulders, we have shown in [5] that the lunar rock samples retrieved from these boulders could also be reconstructed in 3D using photogrammetry applied on archived photographs, in addition to the 360° panoramas. This allowed to setup a comprehensive 3D model of Staton 6, that can be explored in Virtual Reality (VR) [5]. The present work is focused on reconstructing the next waypoint, the “Station 7” geologic sampling site, also lying at the base of the North Massif
Photogrammetric processing of MSL images: a case study at the Mont Mercou outcrop in Gale crater on Mars
No full textInternational audienceThe Curiosity Mars rover spent more than 70 sols to investigate the Mont Mercou outcrop in Gale crater in 2021 [1], capturing a unique set of image data with wide spatial coverage and high overlap. This allowed us to create a high resolution 3D Digital Outcrop Model (DOM) using 6825 images from the rover's Mastcam and Navcam instruments with a Structure from Motion (SfM) process. This process is often difficult and time intensive, so we developed a new Python-based pre-processing pipeline to make the creation of large DOMs more straightforward
Prow & co.: inside the fluvial lenses of Gale's layered sulfate unit
No full textInternational audienceFor three years, the Curiosity rover has been exploring the layered sulfate unit (LSu) of Gale crater, Mars. Not only interesting as a potential record of a monotonic environmental shift towards arid conditions at the Noachian-Hesperian transition, we now know that this interval evidences complex environmental parameters which are characterized by alternating wetter and drier conditions at various timescales [1-3]. Such changes in depositional setting are particularly apparent within the Contigo mbr. of the Mirador fm. There, the LSu strata is dominated by stacked, large-scale cross-stratified aeolian sandstones, tens of meters in thickness, that are punctuated by erosion-resistant, decameter-wide, darker-toned and mostly lens-shaped sandstone bodies that suggest a fluvial deposition [4]. Using image data acquired with Mastcam and ChemCam’s RMI, we detail a wealth of sedimentary structures distributed across these lenses, focusing at the Prow outcrop and neighboring buttes (Fig. 1). We also provide a first assessment of the chemical compositions seen by ChemCam’s LIBS at the Prow
Brasser les milliards de l’État grâce au carrousel de la TVA: un guide pratique avec la série d’argent et de sang
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Hypothermic machine perfusion in uterus transplantation in a porcine model: A proof of concept and the first results in graft preservation
No full textInternational audienceIntroduction: Graft optimization is a necessity in order to develop uterus transplantation from brain-dead donors, as a complement to living donors, as these grafts are rare and the last organs retrieved in multiple organ donation. The aim of this study was to assess the feasibility and interest of hypothermic machine perfusion (HMP) in uterus transplantation using a porcine model; secondary outcomes were the evaluation of the graft's tolerance to a prolonged cold ischaemia time and to find new biomarkers of uterus viability.Material and methods: Fifteen uterus allotransplantations were performed in a porcine model, after 18 h of cold ischaemia, divided in three groups: Static cold storage in a HTK solution, HMP (with the VitaSmart (™) machine Bridge to Life Ltd.) with a UW-MP solution, and static cold storage in a UW solution. The main outcome was macroscopic: uterine arteries pulsatility, recoloration, and bleeding at the cut. Secondary outcomes were histological analyses (Zitkute and inflammation scores), caspase3 immunohistochemistry and plasmatic dosage of biomarkers.Results: 14/15 allotransplantations were performed according to the protocol and met the criteria of macroscopic vitality. Grafts treated with HMP (MP did not show significantly more tissue) damage than the recipient's uterus, contrary to grafts in static cold storage, independently of the solution used. This difference disappeared one and 3 h after uterus transplantation. Plasma dosages before and after uterus transplantation did not allow to identify a new biomarker of uterus viability.Conclusions: HMP is feasible in a porcine model, without inflicting damage on the grafts during cold ischaemia time. Grafts exposed to HMP seemed to better endure reperfusion phenomena, but this advantage did not last over time
Optoelectronic properties study of arylamine-functionalized benzothiophenes and benzothiophene S,S-Dioxides. Application in solution-processed organic light-emitting diodes
No full textInternational audienceConjugated organic molecules based on core benzothiophene and benzothiophene S,S-dioxide substituted with triphenylamines at positions 3,5,6 and 2,4,7 were designed and synthesized in a facily manner. All compounds exhibited bright emission within the visible region and were solution processable from halogen-free solvents. Organic light-emitting diode (OLED) devices were fabricated through an air process spin-coating method where all layers except the top cathode were solution processed. Device luminance exceed 1000 cd/m 2 using one compound based on the 2,4,7triphenylaminebenzothiophene S,S-dioxide scaffold which in turn was successfully translated to a large area module slotdie coated on a plastic substrate.</div
Indicateurs statistiques pour la prédiction optimale des temps de défaillance des systèmes de fiabilité stochastique : une approche rationnelle basée sur les attentes
No full textInternational audienceWe introduce a method to estimate the failure time of a class of weighted k-out-of-n systems using the idea of rational expectations, which to the best of our knowledge is a new approach, not found elsewhere in the existing literature. This paper explores the predictive power of several statistical indicators (variance, skewness, kurtosis, Gini coefficient, entropy) and shows how they perform differently as the system approaches global failure. The proposed method is shown to outperform a benchmark prediction model obtained without rational expectations, and our results offer a panoramic view of the predictive power of the statistical indicators under different assumptions about the initial weight distributions
Spatially-Clustered Spatial Autoregressive Models with Application to Agricultural Market Concentration in Europe
No full textInternational audienceIn this paper, we present an extension of the spatially-clustered linear regression models, namely, the spatially-clustered spatial regression (SCSR) model, to deal with spatial heterogeneity issues in clustering procedures. In particular, we extend classical spatial econometrics models, such as the spatial autoregressive model, the spatial error model, and the spatially-lagged model, by allowing the regression coefficients to be spatially varying according to a cluster-wise structure. Cluster memberships and regression coefficients are jointly estimated through a penalized maximum likelihood algorithm which encourages neighboring units to belong to the same spatial cluster with shared regression coefficients. Motivated by the increase of observed values of the Gini index for the agricultural production in Europe between 2010 and 2020, the proposed methodology is employed to assess the presence of local spatial spillovers on the market concentration index for the European regions in the last decade. Empirical findings support the hypothesis of fragmentation of the European agricultural market, as the regions can be well represented by a clustering structure partitioning the continent into three-groups, roughly approximated by a division among Western, North Central and Southeastern regions. Also, we detect heterogeneous local effects induced by the selected explanatory variables on the regional market concentration. In particular, we find that variables associated with social, territorial and economic relevance of the agricultural sector seem to act differently throughout the spatial dimension, across the clusters and with respect to the pooled model, and temporal dimension. Supplementary materials accompanying this paper appear online