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Guglielmo di Conches, Il dialogo di Filosofia, Introduzione, Traduzione e Commento
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CrystalNets: A web app for topology determination of crystalline structures
No full textInternational audienceBecause topology plays a key role in many chemical and physical properties of materials, identification of topology from crystalline structures is a common and important task in materials science. We present here a new web application, CrystalNets, whose user-friendly interface allows scientists to identify and visualize the topology of crystals from their atomic structure in CIF format. The software has a lot of options to customize its features, such as detection of bonding, choice of clustering model, type of materials (inorganic, hybrid, etc). It has a default mode with powerful heuristics, and allows the user to easily visualize and check the topology detected against the full structure. We also improved the underlying CrystalNets.jl Julia library, including a systematic algorithm to handle the complex case of unstable nets
La distribution des champignons mycorhiziens sur les écorces d'arbres corrèle avec la préférence d'hôte de l'orchidée épiphyte tropicale Bulbophyllum variegatum sur l'île de La Réunion
No full textInternational audienceWhile host preference of tropical epiphytic plants is mainly driven by tree abundance and size, the distribution of mycorrhizal fungi among tree species is likely to influence host preference in orchids. Here, we investigated the host preference of ten epiphytic orchids in a one-hectare forest plot in La Réunion, revealing a strong preference in the orchid Bulbophyllum varigatum.Using an Illumina sequencing of the ITS-2 barcode of fungi, we identified fungal communities, including mycorrhizal Tulasnellaceae, both in the bark of host tree species in the area and in the roots of B. variegatum across the island. Bark-dwelling fungal and mycorrhizal communities varied between tree species, with fungal OTUs being specific to the host of B. variegatum. Three of them (one Serendipitaceae and two Tulasnellaceae) were found to be mycorrhizal at different stages of the orchid's life cycle. Our results suggest that the uneven distribution of mycorrhizal fungi between tree barks could influence the host preference of epiphytic orchids, a hypothesis that will require experimental testing.Alors que la préférence d'hôte des plantes épiphytes tropicales dépend principalement de l'abondance et de la taille des arbres, la répartition des champignons mycorhiziens sur les différentes espèces d'arbres est susceptible d'influencer celle des orchidées . Dans cette étude, nous avons étudié la préférence d'hôte de dix orchidées épiphytes dans une parcelle forestière d'un hectare à La Réunion, révélant une forte préférence d'hôte chez l'orchidée Bulbophyllum varigatum. À l'aide d'un séquençage Illumina du code-barre fongique ITS-2, nous avons identifié les communautés fongiques, notamment les Tulasnellaceae mycorhiziens, à la fois dans l'écorce des espèces d'arbres hôtes de la région et dans les racines de B. variegatum à travers l'île. Les communautés fongiques et mycorhiziennes vivant dans l'écorce varient selon les espèces d'arbres, certaines OTUs fongiques étant spécifiques à l'hôte B. variegatum. Trois d'entre elles (un Serendipitaceae et deux Tulasnellaceae) se sont avérées mycorhiziennes à différents stades du cycle de vie de l'orchidée. Nos résultats suggèrent que la répartition inégale des champignons mycorhiziens entre les écorces des arbres pourrait influencer la préférence d'hôte des orchidées épiphytes, une hypothèse qui devra être vérifiée expérimentalement
Nivolumab ± Ipilimumab in Patients With Pretreated Advanced Neuroendocrine Carcinoma: The GCO-001 NIPINEC Randomized Phase II Trial
No full textInternational audiencePURPOSE There is no standard second-line therapy for gastroenteropancreatic (GEP) and lung large-cell neuroendocrine carcinoma (NEC) after the failure of platinum-based chemotherapy. This study aimed to investigate the efficacy of nivolumab ± ipilimumab. METHODS The GCO-001-NIPINEC (ClinicalTrials.gov identifier: NCT03591731 ) trial was a noncomparative, open-label, phase II trial. The main inclusion criteria were age ≥18 years, performance status (PS) ≤2, advanced large- and small-cell GEP-NEC and large-cell lung NEC, and second- or third-line treatment for NECs refractory to platinum-based chemotherapy. Patients were randomly assigned (1:1) and stratified by age and PS to receive nivolumab (3 mg/kg/once every 2 weeks) ± ipilimumab (1 mg/kg/once every 6 weeks) for 2 years or until progression or unacceptable toxicity. The primary end point was objective response rate (ORR) at 8 weeks, assessed by investigators. RESULTS A total of 185 patients (91 in the nivolumab arm and 94 in the nivolumab-ipilimumab arm) were enrolled between December 2018 and March 2021; 169 were analyzed (median age of 64.5 years, 71% male, 91% PS 0-1). The main primary tumor locations were lungs (50%), colorectal (15%), gastroesophageal (14%), and pancreatic (13%) regions. The ORR at 8 weeks was 7.2% (95% CI, 2.7 to 15.1]) in the nivolumab arm and 14.0% (95% CI, 7.4 to 23.1) in the nivolumab-ipilimumab arm. The best ORR was 9.6% and 20.9%, respectively, whereas the median progression-free and overall survival were approximately 2 months and 6 months in both arms. One treatment-related death occurred, in the nivolumab arm. The grade 3-4 adverse events (≥5%) were asthenia (13%), gamma-glutamyl transferase increase (10%), alkaline phosphatase increase (9%), dyspnea (7%), and anemia (6%) in the nivolumab-ipilimumab arm. CONCLUSION Nivolumab-ipilimumab could be a second-/third-line treatment option for patients with NECs. However, given the limited magnitude of benefit, studies are warranted to evaluate its use earlier and/or associated with chemotherapy
Buchpräsentation mit Judith Schalansky und Richard Stoiber (März Verlag, Berlin)
No full textInternational audienceIm Januar 2024 fand in Paris eine internationale Konferenz zum Werk der mit zahlreichen Preisen ausgezeichneten Schriftstellerin und Buchgestalterin Judith Schalansky statt. Die Bedeutung des Buchs als materiales Objekt für ihr kreatives Schaffen zu erkunden, war Ziel dieser von Mandana Covindassamy, Agathe Mareuge und Bénédicte Terrisse organisierten Veranstaltung. Denn Judith Schalanskys zügelloses und ganz überwiegend in der Staatsbibliothek zu Berlin ausgelebtes Interesse an der Buchgeschichte ist konstitutiv für ihr Werk: Was bisher nicht als Literatur galt, wird von ihr in einen ausgeweiteten Literaturbegriff aufgenommen, vom Insularium der Renaissance bis hin zum Schulbuch des 20. Jahrhunderts.Der vorzustellende Tagungsband – Ende 2025 im Berliner Literaturverlag MÄRZ erschienen und von Judith Schalansky selbst gestaltet – denkt Inhalt und Form daher auch zusammen. In der Form eines Readers versammelt er nicht nur die wissenschaftlichen Konferenzbeiträge von 13 Forschenden, sondern zudem Proben jenes Materials, das diese überhaupt erst ermöglichte: Notiertes und Kopiertes, Gesehenes und Gelesenes, Obskures und Erhellendes.Ein Abend im schillernden Graubereich zwischen kreativer Subjektivität und wissenschaftlicher Objektivität – mit Judith Schalansky, Mandana Covindassamy (École Normale Supérieure Paris), Agathe Mareuge (Sorbonne Université), Bénédicte Terrisse (Nantes Université) und Richard Stoiber (März Verlag)
Lanthanide complexes with acetophenone-based push-pull antennas as efficient MRI and two-photon microscopy imaging probes
No full textInternational audienceLanthanide(iii) (Ln3+) complexes possess unique magnetic and optical properties that make them ideal candidates for the development of multimodal MRI and optical probes. However, the requirements for developing effective MRI and optical probes are difficult to meet within a single ligand. Here, we propose the use of a DOTA-type ligand equipped with a pi-extended acetophenone moiety that (i) serves as a coordinating moiety to form stable Ln3+ complexes, (ii) acts as a 2P-excitable push-pull antenna to sensitize Eu3+ luminescence, and (iii) displays a carboxylate handle offering high water solubility and enabling conjugation to biomolecules for targeting purposes. We show that the Ln3+ complexes obtained are kinetically inert and thermodynamically stable. The Gd3+ complex exhibits positive in vivo characteristics with good contrast in all organs and rapid renal clearance, while the corresponding Eu3+ complex has excellent one-photon and two-photon (2P) absorption properties enabling high-quality in vivo 2P microscopy imaging of zebrafish embryos or in vitro imaging of living cells when conjugated to a cell-penetrating peptide
High β‐diversity in fig wasp communities driven by species turnover in widely distributed Neotropical fig trees
No full textInternational audienceWasp communities associated with fig trees, Ficus spp., are a model system to investigate how local and regional processes shape biodiversity across large geographical ranges. We investigated the β‐diversity of fig wasp assemblages associated with three widely distributed Neotropical fig species – F. citrifolia, F. obtusifolia and F. pertusa – using 27 years of spatially extensive sampling across Brazil, Costa Rica and Ecuador. We quantified β‐diversity using the Sørensen index and its components of turnover and nestedness. For all three Ficus species, β‐diversity was high (0.87–0.90), driven primarily by species turnover (85–96% of β‐diversity). Wasp guilds, i.e. gall inducers, kleptoparasites and parasitoids, presented similarly high turnover values. Our results showed that life‐history traits play a role in the variation of β‐diversity, as gall‐inducing species are more host‐specific. In contrast, kleptoparasitic and parasitoid wasps are more likely to use multiple hosts. Mantel tests revealed that both total β‐diversity and the turnover component were often positively correlated with geographic distance, particularly for the most sampled fig species. Despite the exceptional dispersal capacities reported for several fig wasp lineages, our results suggest that competition for limited fig inflorescence resources, along with natural selection for local adaptation, can restrict species' geographic ranges, thus promoting higher levels of species turnover. These findings underscore the complex interplay between dispersal ability, local adaptation and competitive interactions in shaping the composition of fig wasp communities. Consequently, fig wasp systems present a compelling model for investigating the ecological and evolutionary processes driving biodiversity dynamics in specialized plant–insect interactions
Einleitung
No full textTraduction Anglais - AllemandRuin, Hans and Santini, Carlotta. "Einleitung". Nietzsche als Protagonist der europäischen und globalen Kulturen: Über die frühe Rezeption (1890–1930), edited by Hans Ruin and Carlotta Santini, De Gruyter, 2026, pp. 1-12. https://doi.org/10.1515/9783111709567-00
Combining gold(I/III) complexes and ferrociphenol scaffold for the generation of bimetallic complexes with anticancer activity
No full textInternational audienceA series of eleven heterobimetallic Au/Fe complexes featuring [Au(I)-thioglucose tetraacetate], [Au(I)-NHC], [(C^N)Au(III)Cl], [(C^N^C)Au(III)] or [(C^C)Au(III)Cl] fragments and (diphenylphosphino)ferrociphenol or (diphenylphosphino)ferrocene ligands have been synthesized. The compounds were fully characterized by NMR, high-resolution mass spectrometry, elemental analysis, as well as by X-ray diffraction for the representative Au-carbene complex. The electrochemical behavior of the complexes was studied by cyclic voltammetry. While the compounds resulting from (diphenylphosphino)ferrocene displayed a reversible, ferrocene-centered redox process, their analogs obtained from (diphenylphosphino)ferrociphenol showed additional irreversible multielectron redox transitions attributable to the redox-active ferrociphenol fragment. The antiproliferative activity of the complexes was evaluated in vitro on lung (A549) and triple-negative breast (MDA-MB-231) cancer cells and compared to non-cancerous breast cells (MCF-10A). Coordination of the gold fragments by (diphenylphosphino)ferrocene led to the buildup of antiproliferative activity with EC50 down to the submicromolar level. Comparatively, the antiproliferative activities of the analogous bimetallic complexes containing the (diphenylphosphino)ferrociphenol ligand were slightly lower. The ability of the complexes to inhibit thioredoxin reductase (TrxR), an established target of both gold complexes and ferrociphenol, was also investigated, including in oxidative conditions. Bimetallic complexes featuring exchangeable ligands, such as in Au(I)−chlorido, thiolato, and (C^N) cyclometallated Au(III) fragments, showed half-maximal effective concentrations (EC50) values in the nanomolar range, typical of related gold complexes. In contrast, bimetallic complexes bearing stable scaffolds such as Au(I)-NHC (NHC = N-heterocyclic carbene) and bis-cyclometallated (C^N^C) Au(III) required oxidation of the ferrociphenol moiety to induce significant thioredoxin reductase inhibition
