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Summary of taxonomy changes ratified by the International Committee on Taxonomy of Viruses (ICTV) from the Animal DNA Viruses and Retroviruses Subcommittee, 2025
No full textInternational audienceThe International Committee on Taxonomy of Viruses (ICTV) holds a ratification vote annually after review of newly proposed taxa by ICTV Study Groups and members of the virology community. In March 2025, the vote outcome of the 11 proposals within the mandate of the Animal DNA Viruses and Retroviruses Subcommittee was made public. Here, we provide a summary of the newly accepted proposals. These include reorganization of taxa in the realm Varidnaviria , classification of the ‘polinton-like’ viruses into a new family ( Phypoliviridae ) within a new order Archintovirales ; establishment of a new phylum ( Commensaviricota ) in the kingdom Shotokuvirae ; the establishment of a new family called Filamentoviridae with two new genera and three new species; the addition of four new genera in the family Anelloviridae with 70 new species; and the addition of 85 new species in the families Adenoviridae ( n =16), Baculoviridae ( n =5), Circoviridae ( n =5), Parvoviridae ( n =55) and Polyomaviridae ( n =4). Also, in the family Belpaoviridae , 11 species were renamed to comply with the binomial requirement for species names
La transposase 5 dérivée de piggyBac (PGBD5) peut interagir avec des éléments de type piggyBac humains.
No full textPGBD5 is encoded by a gene domesticated at the chordate origin from a DNA transposon of the piggyBac family. During its evolution, PGBD5’s sequence has been under strong purifying selection among vertebrate genomes. This suggests PGBD5 functions in the development and physiology of chordates, as recently demonstrated in mouse and human brain development, where it was implicated in double strand DNA breaks on neurons. However, biochemical PGBD5 activities remain undefined due to lack of appropriate in vitro model systems. Furthermore, coevolution of PGBD5 with hosts has likely reshaped some of its functions, resulting in differences between vertebrate PGBD5 and the insect piggybac transposase (PB). Recent studies have found that PGBD5 can interact with two different “species” of piggyBac -like transposon element ( pble ). Here, we show that human PGBD5 can interact with four “species” human pbles and to promote their chromosomal integration in cells, a property it shares with insect PB. Human PGBD5 can also bind to distinct chromosomal copies of human pble in cell type-specific manner, and to genomic loci containing inverted repeats in human cells akin to those found in subterminal insect pble ends. These findings expand the scope of potential biological activities of PGBD5 and other domesticated DNA transposases
Low leakage and high blocking voltage GaN-on-GaN Schottky diode by TMAH surface treatment
No full textInternational audienceIn this study, the impact of surface treatment by TMAH and HF on the electrical characteristics of GaN-on-GaN Schottky diodes is examined through I-V and C-V characterizations. A TMAH surface treatment leads to an improvement in the reverse characteristics of the devices and improvement in breakdown voltage (BV) by almost 200 V compared to HF treatment. Additional XPS characterizations reveal a reduction in both O and C concentration from the surface due to TMAH treatment. When combined with proper edge termination techniques, this approach can help achieve breakdown voltages that are closer to the theoretical limits
A new high-entropy perovskite (LaNdSmSrBa)Co0.2Fe0.8O3-δ oxygen electrodes for reversible solid oxide cells
No full textInternational audienc
Male goats exposed to the “male-to-male effect” stimulate the reproductive activity and ensure high fertility of both does and male goats during the non-breeding season
No full textInternational audienceMale goats stimulated by the "male-to-male effect" for one month and then introduced to anestrous does are as efficient as those stimulated by photoperiod in inducing cyclicity in anestrous does. Here, we determined whether the sexually active (SA) male goats can stimulate reproduction in does and males when housed together in the same flock during the non-breeding season, and whether male goats exposed to the "male-to-male effect" can fertilize does with the same efficiency and timeframe as SA males stimulated by photoperiod. In March, one group of does was kept isolated from male goats, while three other groups were housed with seasonally hypoactive males (SH). In April, the isolated group was joined with two SA male goats (SA group), while the other three groups were managed as follows: one group was joined with two SA male goats (SA + SH group); the second group was joined with two SA male goats which were fitted with aprons to prevent mating (SA-apron + SH group); and the third group was joined with two SH male goats (SH + SH group). The percentages of does that kidded did not differ among SA (73 %), SA + SH (70 %) and SA-apron + SH (76)% groups; however, all three had greater kidding rates than the SH + SH group (29 %). We conclude that SA male goats stimulate the reproductive activity in both does and male goats during non-breeding season when housed together in the same group. Furthermore, male goats stimulated by the "male-to-male effect" can achieve fertility rates and fertilization timeframe comparable to those of SA male goats
Neural Field Equations and Hawkes processes: long-term stability of traveling wave profiles in the neutral case
No full textWe consider the long-time behavior of a population of interacting Hawkes processes on the real line, with spatial extension. The large population behavior of the system is governed by the standard Voltage-based Neural Field Equation (NFE). We prove long-time stability of the system w.r.t. traveling wave solutions for the NFE on a diffusive time scale, in the neutral case, that is when the speed of the traveling wave solution is zero: the position of the traveling wave profile becomes essentially Brownian on a diffusive time scale. We borrow here from the seminal work of Chevallier, Duarte, L\"ocherbach and Ost concerning the approximation of NFE by Hawkes processes, the existence result of traveling waves of Ermentrout and McLeod and from the stability result of the traveling wave profile from Lang and Stannat. We provide also similar results concerning the activity based NFE
Vers une réévaluation des tests de Bell : un protocole expérimental sans filtrage des coïncidences
No full textThe experiments carried out by Alain Aspect, and all the following ones, made it possible to test John Stewart Bell's inequalities by comparing the predictions of quantum mechanics with the more general ones of local hidden variable models. Starting from the observation that, for quantum mechanics, only coincidence situations exist and that the predictions therefore only concern these, we develop here a local model based on Malus's law which provides for the value S a prediction close to that of quantum mechanics and compatible with the known experimental results. This situation, paradoxical compared to Bell's theorem, can be explained by the statistical bias generated by the coincidence filtering operation in the experimental protocol. To experimentally validate this local model which violates Bell's inequalities, we propose an original protocol which should make it possible to determine whether or not the filtering operation creates a statistical bias. The experimental confirmation of this bias would strongly invalidate the current conclusions of previous experiments, namely the completeness of quantum mechanics.Les expériences réalisées par Alain Aspect, et toutes les suivantes, ont permis de tester les inégalités de John Stewart Bell en comparant les prédictions de la mécanique quantique avec celles, plus générales, des modèles locaux à variables cachées. Partant de l'observation que, pour la mécanique quantique, seules les situations de coïncidences existent et que les prédictions ne concernent donc que celles-ci, on développe ici un modèle local basé sur la loi de Malus qui fournit pour la valeur S une prédiction proche de celle de la mécanique quantique et compatible avec les résultats expérimentaux connus. Cette situation, paradoxale par rapport au théorème de Bell, peut s'expliquer par le biais statistique engendré par l'opération de filtrage des coïncidences dans le protocole expérimental. Pour valider expérimentalement ce modèle local qui viole les inégalités de Bell, nous proposons un protocole original qui doit permettre de déterminer si l'opération de filtrage crée, ou non, un biais statistique. La confirmation expérimentale de ce biais invaliderait fortement les conclusions actuelles des expériences précédentes, à savoir la complétude de la mécanique quantique
Mapd’O - Un nouvel outil pour la visualisation et l’analyse hydromorphologique des réseaux fluviaux à l’échelle nationale
No full textInternational audienceThe hydro-ecological functioning of river systems is influenced by the physical conditions within their corridors (e.g. topography, land use, geology). A systematic description of the physical functioning has so far been limited due to a lack of data on aspects such as lateral dynamics and floodplain connectivity. The Mapd'O project addresses this by providing datasets and a web interface that allow operators and scientists to analyze these conditions for the entire French river corridor network. Novel datasets such as a national land use map with a resolution of 1 m and the first national valley bottom and lateral continuity maps were created using the Fluvial Corridor Toolbox (FCT), a geographic information system toolbox for network-scale hydromorphic characterisation. Using the Mapd'O app, these datasets can be visualized, analyzed and interpreted to enable hydromorphological diagnosis of river systems at reach to network scales: the entire watershed, but also their sub-catchments and individual river axis level.Le fonctionnement hydro-écologique des systèmes fluviaux est influencé par les conditions physiques au sein de leurs corridors (par exemple, la topographie, l'utilisation des sols, la géologie). Une description systématique du fonctionnement physique a jusqu'à présent été limitée en raison d'un manque de données sur des aspects tels que la dynamique latérale et la connectivité des plaines alluviales. Le projet Mapd'O répond à cette problématique en fournissant des ensembles de données et une interface web qui permettent aux opérateurs et aux scientifiques d'analyser ces conditions pour l'ensemble du réseau fluvial français. De nouveaux jeux des données tels qu'une carte nationale d'occupation des sols avec une résolution de 1 m et les premières cartes nationales de fond de vallée et de continuité latérale ont été créés à l'aide de la Fluvial Corridor Toolbox (FCT), une boîte à outils de système d'information géographique pour l'hydromorphologie à grande échelle. En utilisant l'application Mapd'O, ces données peuvent être visualisées, analysées et interprétées pour faciliter un diagnostic hydromorphologique des rivières à différentes échelles : l'ensemble du bassin versant, mais aussi leur sous-bassin versant et l'échelle de l'axe individuel de la rivière
Spatial variations in runoff, sediment, and nutrient losses induced by toposequence and biochar application in upland maize farming
No full textInternational audienceSoil erosion is a natural process that can be intensified by inappropriate land use and agricultural practices. Therefore, it is essential to gain a deeper understanding of the effects of agro-ecological practices, such as biochar application, on soil erosion processes in upland areas, particularly in Southeast Asia. Moreover, understanding the variations in erosion characteristics across a toposequence is vital for sustaining upland agriculture. The objective of this study was to investigate the effects of toposequence position and biochar application on sediment loss, runoff, and nutrient losses under natural rainfall conditions in Nan Province, Thailand. We installed 24 plots of 1 m² each, located at four positions within the toposequence. The biochar was incorporated into the soil at 5 cm depth. Over two rainy seasons, we regularly measured sediment loss, runoff, and nutrient losses on plots with and without biochar along the four positions of the toposequence. Our findings indicated that the addition of biochar amendments to the topsoil effectively reduced nutrient loss through runoff, particularly nitrogen. This practice also improved vegetation cover, increased soil moisture, and decreased the presence of free elements such as micro- aggregates, gravels, and carbon nodules (biochar) on the soil surface. During the study, we observed the re-emergence of previously integrated biochar on the soil surface after eight months under natural conditions, which manifested as a crust on the soil surface. Positions within the toposequence had a significant impact on various soil properties, including the amount of sediment loss, runoff, and nutrient losses. Therefore, considering the influence of toposequence position is essential for enhancing soil management and implementing suitable agroecological practices
