Vegetable oil hybrid films cross-linked at the air-water interface: formation kinetics and physical characterization

Vegetable oil based hybrid films were developed thanks to a novel solvent- and heating- free method at the air-water interface using silylated castor oil cross-linked via a sol-gel reaction. To understand the mechanism of the hybrid film formation, the reaction kinetics was studied in detail by using complementary techniques: rheology, thermogravimetric analysis, and infrared spectroscopy. The mechanical properties of the final films were investigated by nano-indentation, whereas their structure was studied using a combination of wide-angle X-ray scattering, electron diffraction, and atomic force microscopy. We found that solid and transparent films form in 24 hours and, by changing the silica precursor to castor oil ratio, their mechanical properties are tunable in the MPa-range by about a factor of twenty. In addition to that, a possible optimization of the cross-linking reaction with different catalysts was explored and finally, cytotoxicity tests were performed on fibroblasts proving the absence of film toxicity. The results of this work pave the way to a straightforward synthesis of castor-oil films with tunable mechanical properties: hybrid films cross-linked at the air-water interface combine an easy and cheap spreading protocol with the features of their thermal history optimized for possible future micro/nano drug loading, thus representing excellent candidates for the replacement of non-environment friendly petroleum-based materials

Sanctuaire de source, sanctuaire des eaux ou simple sanctuaire en milieu humide? Découverte d'un complexe cultuel antique à Magny-Cours (Nièvre)

In advance of the future extension of the "technopole" and the construction of a service station in the district of Magny-Cours, the undertaking of two evaluations covering 15 hectares and 4 hectares, respectively, has revealed dense occupation of the site from the Neolithic period to the Middle Ages. The most important remains are associated with the Roman period and belong to a complex endowed with public buildings including several temples in an organised arrangement. This paper, preliminary to a larger study that will report on the whole of the site, is concerned specifically with the results obtained in a waterlogged area comprised within a zone that was excluded from the rescue excavations. Located near the cult buildings, this area was found to contain a deposit of ex-votos belonging to the beginning of the Roman era.À l'occasion de la future extension du " technopole " sur la commune de Magny-Cours et la création d'une aire de service, la réalisation de deux diagnostics sur 15 ha et 4 ha a permis la mise en évidence d'une occupation dense du Néolithique au Moyen Âge. La période antique rassemble l'essentiel des vestiges, appartenant à un complexe doté de monuments publics dont plusieurs temples à plan centré. Cet article, préambule à une étude globale qui concernera l'ensemble du site, se limite à la présentation des résultats acquis dans une zone humide exclue de la fouille préventive. Située à proximité d'édifices cultuels, elle a livré un dépôt d'ex-voto remontant au début de la période romaine

Unprecedented inequivalent metal coordination environments in a mixed-ligand dicobalt complex

Bimetallic complexes of the transition metals containing mixed diimine and dithiolate ligands are of fundamental interest on account of their intriguing electronic properties. Almost always, such complexes are isolated as species in which both the metal centers are in identical coordination environments - this means that the two metals often have identical redox properties. In contrast, mixed-diimine/dithiolate bimetallic complexes of the first row transition metals where the two metals are in dissimilar coordination environments are exceedingly rare, and are only known for nickel. Herein, we report the first ever example of a mixed-diimine/dithiolate dicobalt complex where the two cobalt centers are in different coordination environments. The synthesis of this compound is straightforward, and produces a complex in which the two cobalt centers display very different redox properties

Targeting Class A and C Serine \u3b2-Lactamases with a Broad-Spectrum Boronic Acid Derivative

Production of \u3b2-lactamases (BLs) is the most widespread resistance mechanism adopted by bacteria to fight \u3b2-lactam antibiotics. The substrate spectrum of BLs has become increasingly broad, posing a serious health problem. Thus, there is an urgent need for novel BL inhibitors. Boronic acid transition-state analogues are able to reverse the resistance conferred by class A and C BLs. We describe a boronic acid analogue possessing interesting and potent broad-spectrum activity vs class A and C serine-based BLs. Starting from benzo(b)thiophene-2-boronic acid (BZBTH2B), a nanomolar non-\u3b2-lactam inhibitor of AmpC that can potentiate the activity of a third-generation cephalosporin against AmpC-producing resistant bacteria, we designed a novel broad-spectrum nanomolar inhibitor of class A and C BLs. Structure-based drug design (SBDD), synthesis, enzymology data, and X-ray crystallography results are discussed. We clarified the inhibitor binding geometry responsible for broad-spectrum activity vs serine-active BLs using double mutant thermodynamic cycle studies

Circulating adrenomedullin estimates survival and reversibility of organ failure in sepsis: the prospective observational multinational Adrenomedullin and Outcome in Sepsis and Septic Shock-1 (AdrenOSS-1) study

Background: Adrenomedullin (ADM) regulates vascular tone and endothelial permeability during sepsis. Levels of circulating biologically active ADM (bio-ADM) show an inverse relationship with blood pressure and a direct relationship with vasopressor requirement. In the present prospective observational multinational Adrenomedullin and Outcome in Sepsis and Septic Shock 1 (, AdrenOSS-1) study, we assessed relationships between circulating bio-ADM during the initial intensive care unit (ICU) stay and short-term outcome in order to eventually design a biomarker-guided randomized controlled trial. Methods: AdrenOSS-1 was a prospective observational multinational study. The primary outcome was 28-day mortality. Secondary outcomes included organ failure as defined by Sequential Organ Failure Assessment (SOFA) score, organ support with focus on vasopressor/inotropic use, and need for renal replacement therapy. AdrenOSS-1 included 583 patients admitted to the ICU with sepsis or septic shock. Results: Circulating bio-ADM levels were measured upon admission and at day 2. Median bio-ADM concentration upon admission was 80.5 pg/ml [IQR 41.5-148.1 pg/ml]. Initial SOFA score was 7 [IQR 5-10], and 28-day mortality was 22%. We found marked associations between bio-ADM upon admission and 28-day mortality (unadjusted standardized HR 2.3 [CI 1.9-2.9]; adjusted HR 1.6 [CI 1.1-2.5]) and between bio-ADM levels and SOFA score (p < 0.0001). Need of vasopressor/inotrope, renal replacement therapy, and positive fluid balance were more prevalent in patients with a bio-ADM > 70 pg/ml upon admission than in those with bio-ADM ≤ 70 pg/ml. In patients with bio-ADM > 70 pg/ml upon admission, decrease in bio-ADM below 70 pg/ml at day 2 was associated with recovery of organ function at day 7 and better 28-day outcome (9.5% mortality). By contrast, persistently elevated bio-ADM at day 2 was associated with prolonged organ dysfunction and high 28-day mortality (38.1% mortality, HR 4.9, 95% CI 2.5-9.8). Conclusions: AdrenOSS-1 shows that early levels and rapid changes in bio-ADM estimate short-term outcome in sepsis and septic shock. These data are the backbone of the design of the biomarker-guided AdrenOSS-2 trial. Trial registration: ClinicalTrials.gov, NCT02393781. Registered on March 19, 2015

Ceratonia siliqua: a non-nodulated legume hosting nodulating bacterial endophytes

Parmi les légumineuses, 3 sous-familles sont reconnues : les Papilionoideae, les Mimosoideae et les Caesalpinioideae. Si les deux premières comportent très majoritairement des espèces nodulées, chez les Caesalpinioideae la nodulation ne concerne que 5% des gemes. Parmi les différents clades des Caesalpinioideae, le plus proche des Mimosoideae comprend en particulier le geme Ceratonia. Le caroubier, Ceratonia siliqua, est un arbre cultivé et apprécié en zone méditerranéenne, en tant que fruitier. Il n'est pas nodulé mais est mycorhizé (mycorhizes arbusculaires). L'objectif de notre travail est d'étudier la diversité des bactéries associées aux racines de cette espèce en relation avec la mycorhization. Notre approche s'est déroulée en trois étapes. Sur le terrain nous avons récolté dans différents sites des feuilles de caroubier et d'espèces non légumineuses et légumineuses voisines afin (1) d'analyser le comportement du caroubier vis à vis de la fixation biologique de l'azote par l'analyse de l'abondance isotopique naturelle en 15N. Des racines et du sol sous caroubier ont également été récoltées afin d'évaluer la mycorhization arbusculaire et (2) d'analyser les communautés microbiennes naturellement associées au caroubier. A partir de fragments racinaires stérilisés en surface, (3) des essais d'isolements bactériens ont été réalisés. Les isolats obtenus ont été sélectionnés sur leur capacité à induire soit la nodulation monoxénique soit un phénotype de gonflement racinaire, chez deux légumineuses à large spectre de nodulation : Macroptilium atropurpureum et Mimosa pudica. Les souches positives pour l'un ou l'autre de ces phénotypes ont été caractérisées par séquençage de leur ADNr 16S. Les résultats des différentes analyses seront présentés et commentés en fonction des données obtenues aux différents niveaux d'analyse et de la littérature. (Résumé d'auteur

Human influence on growing-period frosts like the early April 2021 in Central France

International audienceAbstract. In early April 2021 several days of harsh frost affected central Europe. This led to very severe damage in grapevine and fruit trees in France, in regions where young leaves had already unfolded due to unusually warm temperatures in the preceding month (March 2021). We analysed with observations and 172 climate model simulations how human-induced climate change affected this event over central France, where many vineyards are located. We found that, without human-caused climate change, such temperatures in April or later in spring would have been even lower by 1.2 ∘C (0.75 to 1.7 ∘C). However, climate change also caused an earlier occurrence of bud burst that we characterized in this study by a growing degree day index value. This shift leaves young leaves exposed to more winter-like conditions with lower minimum temperatures and longer nights, an effect that overcompensates the warming effect. Extreme cold temperatures occurring after the start of the growing season such as those of April 2021 are now 2 ∘C colder (0.5 to 3.3 ∘C) than in preindustrial conditions, according to observations. This observed intensification of growing-period frosts is attributable, at least in part, to human-caused climate change with each of the five climate model ensembles used here simulating a cooling of growing-period annual temperature minima of 0.41 ∘C (0.22 to 0.60 ∘C) since preindustrial conditions. The 2021 growing-period frost event has become 50 % more likely (10 %–110 %). Models accurately simulate the observed warming in extreme lowest spring temperatures but underestimate the observed trends in growing-period frost intensities, a fact that yet remains to be explained. Model ensembles all simulate a further intensification of yearly minimum temperatures occurring in the growing period for future decades and a significant probability increase for such events of about 30 % (20 %–40 %) in a climate with global warming of 2 ∘C

Сверхлегкие генераторные модули для КВЧ-терапии

Разработаны миниатюрные генераторные модули для КВЧ-терапии, лег-ко фиксируемые в любом месте тела пациента. Могут быть использованы не только в медицине

Gut Pathology and Responses to the Microsporidium Nosema ceranae in the Honey Bee Apis mellifera

The microsporidium Nosema ceranae is a newly prevalent parasite of the European honey bee (Apis mellifera). Although this parasite is presently spreading across the world into its novel host, the mechanisms by it which affects the bees and how bees respond are not well understood. We therefore performed an extensive characterization of the parasite effects at the molecular level by using genetic and biochemical tools. The transcriptome modifications at the midgut level were characterized seven days post-infection with tiling microarrays. Then we tested the bee midgut response to infection by measuring activity of antioxidant and detoxification enzymes (superoxide dismutases, glutathione peroxidases, glutathione reductase, and glutathione-S-transferase). At the gene-expression level, the bee midgut responded to N. ceranae infection by an increase in oxidative stress concurrent with the generation of antioxidant enzymes, defense and protective response specifically observed in the gut of mammals and insects. However, at the enzymatic level, the protective response was not confirmed, with only glutathione-S-transferase exhibiting a higher activity in infected bees. The oxidative stress was associated with a higher transcription of sugar transporter in the gut. Finally, a dramatic effect of the microsporidia infection was the inhibition of genes involved in the homeostasis and renewal of intestinal tissues (Wnt signaling pathway), a phenomenon that was confirmed at the histological level. This tissue degeneration and prevention of gut epithelium renewal may explain early bee death. In conclusion, our integrated approach not only gives new insights into the pathological effects of N. ceranae and the bee gut response, but also demonstrate that the honey bee gut is an interesting model system for studying host defense responses

Biodiversité et dégradation des terres. Un combat commun pour le développement durable en zones sèches

" La diversité du vivant décline globalement à un rythme sans précédent dans l'histoire humaine ". La plate-forme intergouvernementale sur la biodiversité et les services écosystémiques (IPBES) dresse en 2019 un constat alarmant sur l'état de la biodiversité de la planète et nous appelle toutes et tous à (ré)agir au plus vite. Selon l'IPBES, environ 1 million d'espèces vivantes seraient menacées et l'érosion des populations interviendrait à un rythme 100 à 1 000 fois supérieurs à ceux des précédents processus d'extinction. Qu'en est-il des zones sèches ? Le CSFD donne son point de vue et propose neuf recommandations pour à la fois lutter contre la dégradation des terres et de la biodiversité, et appuyer le développement durable dans ces régions