Microstructure and mechanical properties of high strength steel deposits obtained by Wire-Arc Additive Manufacturing

Wire-arc additive manufacturing has become an alternative way to produce industrial parts. In this work 15 kg walls are built with an effective building rate of 4.85 kg/h using an ER100 wire providing good tensile properties and toughness under welding conditions. The thermal evolution of the walls during manufacturing is measured by thermocouples and an IR camera: it depends on process parameters, deposit strategy and the size of the part. The walls are then characterised as deposit and after heat treatment through hardness, tensile and Charpy-V notch tests. The results show a fine microstructure with unexpected retained austenite and coarse allotriomorphic ferrite in the as deposited walls. The final hardness values vary from about 220 to 280 HV2; the yield stress and tensile strength are 520 and 790 MPa, respectively, and a toughness of about 50 J is obtained at room temperature. The heat treatment transforms the retained austenite, leading to an improvement of the yield stress to 600 MPa

Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome associated with COVID-19: An Emulated Target Trial Analysis.

RATIONALE: Whether COVID patients may benefit from extracorporeal membrane oxygenation (ECMO) compared with conventional invasive mechanical ventilation (IMV) remains unknown. OBJECTIVES: To estimate the effect of ECMO on 90-Day mortality vs IMV only Methods: Among 4,244 critically ill adult patients with COVID-19 included in a multicenter cohort study, we emulated a target trial comparing the treatment strategies of initiating ECMO vs. no ECMO within 7 days of IMV in patients with severe acute respiratory distress syndrome (PaO2/FiO2 <80 or PaCO2 ≥60 mmHg). We controlled for confounding using a multivariable Cox model based on predefined variables. MAIN RESULTS: 1,235 patients met the full eligibility criteria for the emulated trial, among whom 164 patients initiated ECMO. The ECMO strategy had a higher survival probability at Day-7 from the onset of eligibility criteria (87% vs 83%, risk difference: 4%, 95% CI 0;9%) which decreased during follow-up (survival at Day-90: 63% vs 65%, risk difference: -2%, 95% CI -10;5%). However, ECMO was associated with higher survival when performed in high-volume ECMO centers or in regions where a specific ECMO network organization was set up to handle high demand, and when initiated within the first 4 days of MV and in profoundly hypoxemic patients. CONCLUSIONS: In an emulated trial based on a nationwide COVID-19 cohort, we found differential survival over time of an ECMO compared with a no-ECMO strategy. However, ECMO was consistently associated with better outcomes when performed in high-volume centers and in regions with ECMO capacities specifically organized to handle high demand. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Use of Renewable Resources Towards the Sustainable Production of Crop Protection Agents

Today, the production of food accounts for roughly one quarter of the anthropogenic greenhouse gas emissions. Since the 1970s, thanks to substantial research and development, the overall yield output in farm fields has increased by ca. 60%, while the net use of crop protection agents per square meter of farm field has been reduced by more than 90%. The development of modern crop protection agents remains an important need as new pests, diseases and weeds continue to affect crops. The vast majority of these effective solutions are manufactured using raw materials that ultimately come from fossil resources. In this article, we are touring within the agrochemical landscape to provide the reader with an overview of concrete examples on how in this industrial field, renewable and sustainable raw materials have been used to produce active ingredients. We are also discussing the opportunities for future development as well as some of the challenges and needs that are emerging

Long-term functional outcomes of perineal gangrene: worse than expected?-an observational retrospective study

International audiencePurpose - For survivors of perineal gangrene (PG), quality of life and functional prognosis of pelvic functions are probably overestimated. The aim of this study was to report long-term anal and urinary sphincter dysfunctions, sexual sequelae, and patients' quality of life after treatment of perineal gangrene. Methods - This retrospective observational study was conducted in one university hospital over 16 years. Seventy-three patients experienced PG; 22 were subject to long-term follow-up. Three questionnaires were sent to patients to assess pelvic dysfunction and quality of life: the GIQLI, the Cleveland Incontinence Score, and the USP score for urinary dysfunction. Sexual sequelae were considered if orchiectomy or penile resection for male patients and vulvar resection for female patients were performed. Results - Of the 72 patients included, seven died before discharge (9.7%) and at least 14 died during follow-up (19.4%), despite a mean age of 62 years (± 13). Among the surviving patients, seven experienced an alteration of their quality of life (44%) (GIQLI < 96). Six patients still had a colostomy, and among the remaining patients, 11 experienced minimal to mild incontinence (68.7%), while one experienced constipation (6.2%). One patient suffered from urinary incontinence (4.5%), and six suffered from dysuria (27.3%). Three male patients (14%) underwent an orchiectomy, and one female patient (100%) underwent a vulvar resection. Conclusion - PG leads to a high rate of anal and urinary dysfunctions. Urinary dysfunctions are taken into account and treated; however, anal incontinence is not investigated even though it could lead to decreased quality of life

Analyse bioinformatique des marques d'histone chez le poulet exposé à la chaleur pendant l'incubation

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Analyse bioinformatique des modifications post-traductionnelles des histones chez le poulet thermomanipulé durant l'embryogenèse

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Environmental epigenetics in birds: when the embryo feels the heat

National audienceChanges in gene activity through epigenetic alterations induced by early environmental challenges during the embryogenesis are known to impact the phenotype, health and disease risk of animals. The epigenome is therefore an essential contributor to phenotypic plasticity, and learning how environmental exposures translate into persisting epigenetic changes may open new doors to improve robustness and resilience of developing animals. Birds are agronomic species of choice to directly manipulate the embryonic environment with limited maternal impact and to study its consequences on the developing animal. We previously showed that the heat tolerance of male commercial chickens was improved by cyclically elevating the egg incubation temperature. This treatment named embryonic thermal manipulation (TM) was associated with changes in gene expression that persisted during the development of chickens and enhanced gene expression response in case of heat challenge at slaughter age, 35 days post-hatch. To further explore the molecular basis of heat acclimation, we took advantage of an inbred line of Japanese quails (Coturnix japonica) to investigate the impact of TM on bird methylome. Among other advantages, quail generation cycle is 3-4 time faster than chicken and the use of an inbred genotype should reduce the phenotype variations associated with genetic variability. A characterization of TM on quail phenotype was performed in interaction with a post-hatch heat stress at the onset of sexual maturity. Notably, we observed an impact of the embryonic treatment on the temperature and the weight of young quails, similarly to what was reported for chicken. Concomitantly we investigated the impact of TM on quail transcriptome by RNA-seq and methylome by whole genome bisulfite sequencing (WGBS) on brain tissues sampled at hatch. Several differentially expressed genes and methylated regions were identified. Interestingly, the nature of some transcripts seemed to be affected by the embryonic treatment at both methylation and transcript levels

Thermal Manipulation During Embryogenesis Impacts H3K4me3 and H3K27me3 Histone Marks in Chicken Hypothalamus

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La grotte Huchard (Saint-Martin-d'Ardèche ; Ardèche) : approche chronologique intégrée d'une grotte ornée paléolithique à la sortie des gorges de l'Ardèche

International audienceResearch was carried out at Huchard Cave in 2020 and 2021 as part of the "Cave Art Dating" project. The aim of this project, since 2008, is to investigate the chronology of human and animal activities in the Palaeolithic rock art caves of the Ardèche river gorge, and the ways prehistoric human groups made sense and symbolically inscribed subterranean landscapes, as well as the socio-cultural contexts in which Palaeolithic cave art was created.In 2016, a visit to Huchard Cave highlighted its chronological potential and the interest in resuming research at the site.Huchard Cave, also known as Grotte du Ranc Pointu no1 or Grotte du Squelette, is located in the last meander of the Ardèche river gorge (Saint-Martin-d'Ardèche; Ardèche). In 1908, P. Raymond reported deep engravings, attributed to the Upper Palaeolithic in its penumbra zone, between 2.5 and 3.5 m above the current ground.The position of Huchard Cave among a series of seven rock art caves in the “Ranc Pointu site complex” raises the question of the possible complementarity of their – functional and/or symbolic – uses. The proximity of Deux-Ouvertures and Huchard Caves, and the latter's position as a compulsory passageway to the former raise the question of whether they should be considered as a single site. Are there contemporaneous phases of use of these two caves, as well as the other rock art caves in the Ranc Pointu meander? And, if so, what reciprocal interactions could have existed between them at an anthropological and sociological level?While the chronology established in the Deux-Ouvertures and most of the rock art caves of the Ranc Pointu meander provide an overview of human activity in the sector, Huchard Cave had not yet benefited from an in-depth study. Since the end of the 19th century, various archaeological operations have been carried out at Huchard Cave. But the chronology of human activity in the cave during the Upper Palaeolithic remained imprecise.In 2016, we identified against the walls some remains of the sedimentary levels excavated in 1957 by P. Huchard. These observations prompted an archaeological operation in 2020 and 2021. The aim was to obtain an age for the archaeological remains contained in these deposits and to test the chronocultural attribution previously proposed on the basis of lithic material. It was also the opportunity to check whether other chronological phases were present and to discuss the morphology of the floor during the Upper Palaeolithic.To achieve this, we focused on: (1) a 3D digital recording of the cave, the engravings and the deposits remaining against the wall, (2.1) a geoarchaeological study of the sedimentary deposits, (2.2) an analysis of the archaeological palaeontological and paleoenvironmental material they contained, (3) a study of the natural and anthropogenic traces on the walls, and (4) an approach to the geometry of past sedimentary fillings of the cave and their chronological and spatial positioning in relation to the parietal engravings.In the end, we identified 6 siliceous lithic pieces, 56 microcharcoal, 4 elements of red colouring matter, 3 pebbles and 3 remains of microfauna on the surface of the residual sedimentary deposits of the diverticulum. These remains were mainly concentrated in, on the upper 12 to 17 cm of the deposits (SU 1). Radiocarbon measurements yielded seven dates ranging from 16,330 to 13,250 cal. BP. This chronological range is compatible with the Upper Magdalenian attribution previously proposed by J. Combier on the basis of the lithic industry. However, the 14C ages obtained suggest that human presence also took place during the Epipaleolithic. The geoarchaeological observations and the results of the lithic and anthracological studies are also consistent with the cultural and paleoenvironmental data available for the Upper Palaeolithic in the region. Although not providing precise chronological information, the presence of colouring matter, pebbles and faunal remains is compatible as well with an Upper Palaeolithic age. The only divergent data comes from palynology. The long use of the cave as a sheepfold during the Holocene period, the circulation of water in the sediment of SU 1 and the exposition of the stratigraphy to the open air for more than 60 years, are all possible sources of pollution that could explain these discrepancies.The altitude of the engravings is compatible with Palaeolithic circulation floors at the level of the archaeological layer (SU 1). The engraved wall would then be within the manual range of a medium-sized individual (1.70 m). However, we identified a discordance between SU 1 and SU 2. This gap covers a period from the Early Dryas to potentially the Middle Pleistocene. Although there is no archaeological evidence to substantiate it, we cannot dismiss the creation of the engravings during this pre-Magdalenian period.Regarding the socio-cultural interplay between the various rock art caves of the Ranc Pointu meander, we identified archaeological and spatial similarities between Huchard cave and the other engraved caves (Chabot, Figuier and, to a lesser extent, Sombre Caves). These four rock art caves are the manifestation of phenomena that seem chronologically related (pre-Magdalenian) and anthropologically similar (dwelling sites), albeit with possible complementarities. Apart from Figuier cave, no evidence of recent Upper Palaeolithic and/or Epipalaeolithic occupation, contemporary with that of Huchard cave, is known in these caves. It may be due to the early nature of the excavations carried out there, or it could indicate an older age for Huchard Cave engravings. In fact, both in Huchard and Figuier Caves, the presence of Magdalenian remains may simply reflect the relatively marked presence of this chronological period in the Ardèche river gorge.As for potential connections with the three caves of the Ranc Pointu meander whose rock art is located in total darkness (Tête-du-Lion, Deux-Ouvertures, and possibly Saint-Marcel), there is a chronological dissimilarity between the periods of human activity in these caves and the dates of occupation of Huchard Cave. It is therefore difficult to support the hypothesis of regular and/or intensive Magdalenian interactions between interior spaces located in total darkness and residential spaces with rock engravings in the semi-dark zone of Huchard, Chabot and Figuier Caves. This observation calls into question the pre-Magdalenian nature of the engravings of Huchard Cave and, consequently, suggests a possible chronological disjunction between the age of the remains found in its sedimentary deposits and the age of its parietal engravings.The Ranc Pointu meander thus emerges as an ensemble in its own that needs to be understood as a whole. The results obtained at Huchard Cave represent an important milestone opening up further prospects for research on the scale of this complex of sites.Une approche intégrée de la grotte Huchard, ou grotte du Ranc pointu no1, a été menée en 2020 et 2021. Elle a eu pour objectif d’investiguer les éventuelles complémentarités d’usages fonctionnels et/ou symboliques ayant pu exister entre les différentes grottes ornées du « complexe de sites » du Ranc pointu, dont fait partie la grotte Huchard. Ceci a impliqué d’aborder au préalable la question de la contemporanéité d’une ou de plusieurs phase/s de fréquentation de ces cavités. Pour ce faire, plusieurs opérations ont été réalisées, à savoir : un enregistrement numérique 3D de la cavité, une étude des lambeaux de remplissage laissés par les fouilles de 1957 et des vestiges qu’ils comprennent, ainsi qu’une approche de la géométrie des remplissages et de leur position vis-à-vis des gravures pariétales.Les âges 14C obtenus sur charbons dans ces placages sédimentaires se placent entre 16 330 et 13 250 cal. BP. Globalement cohérents avec le reste des études, ces résultats viennent confirmer les attributions chronoculturelles proposées antérieurement sur la base du matériel lithique (Magdalénien supérieur), tout en les étendant significativement à l’Épipaléolithique. La position altitudinale des gravures pariétales est, par ailleurs, compatible avec des sols de circulation dans la continuité des niveaux archéologiques de l’US 1.Du point de vue des relations entre les différentes grottes ornées du méandre du Ranc pointu, la rareté des traces d’activité humaine attribuables au Paléolithique supérieur récent dans les zones d’obscurité des cavités du secteur ressort nettement. Ce constat rend difficile de soutenir l'hypothèse d'interactions intenses et/ou régulières au Magdalénien supérieur entre des espaces situés dans l'obscurité totale (Deux-Ouvertures, Tête-du-Lion) et des espaces de résidence dotés d’une ornementation en entrée de grotte (Huchard, Chabot, Figuier). Au contraire, ceci amène à s’interroger sur le caractère anté-magdalénien des gravures de la grotte Huchard et, par conséquent, sur une possible disjonction chronologique entre l’âge des vestiges retrouvés dans les dépôts sédimentaires et l’âge des gravures pariétales