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We used ancient DNA (aDNA) extraction methods to sequence museum voucher samples of Oligobrachia webbi, a frenulate siboglinid polychaete described from a northern Norwegian fjord over fifty years ago. Our sequencing results indicate a genetic match with the cryptic seep species, Oligobrachia haakonmosbiensis (99% pairwise identity for 574 bp mtCOI fragments). Due to its similarity with O. webbi, the identity of O. haakonmosbiensis has been a matter of debate since its description, which we have now resolved. Furthermore, our results demonstrate that chemosynthesis-based siboglinids, that constitute the bulk of the biomass at Arctic seeps are not seep specialists. Our data on sediment geochemistry and carbon and nitrogen content reveal reduced conditions in fjords/sounds, similar to those at seep systems. Accumulation and decomposition of both terrestrial and marine organic matter results in the buildup of methane and sulfide that apparently can sustain chemosymbiotic fauna. The occurrence of fjords and by extension, highly reducing habitats, could have led to Arctic chemosymbiotic species being relatively generalist with their habitat, as opposed to being seep or vent specialists. Our stable isotope analyses indicate the incorporation of photosynthetically derived carbon in some individuals, which aligns with experiments conducted on frenulates before the discovery of chemosynthesis that demonstrated their ability to take up organic molecules from the surrounding sediment. Since reduced gases in non-seep environments are ultimately sourced from photosynthetic processes, we suggest that the extreme seasonality of the Arctic has resulted in Arctic chemosymbiotic animals seasonally changing their degree of reliance on chemosynthetic partners. Overall, the role of chemosynthesis in Arctic benthos and marine ecosystems and links to photosynthesis may be complex, and more extensive than currently known.

Rimicaris exoculatashrimps from hydrothermal vent ecosystems are known to host dense epibiotic communities inside their enlarged heads and digestive systems. Conversely, other shrimps from the family, described as opportunistic feeders have received less attention. We examined the nutrition and bacterial communities colonizing “head” chambers and digestive systems of three other alvinocaridids –Rimicaris variabilis,Nautilocaris saintlaurentaeandManuscarissp. – using a combination of electron microscopy, stable isotopes and sequencing approaches. Our observations inside “head” cavities and on mouthparts showed only a really low coverage of bacterial epibionts. In addition, no clear correlation between isotopic ratios and relative abundance of epibionts on mouthparts could be established among shrimp individuals. Altogether, these results suggest that none of these alvinocaridids rely on chemosynthetic epibionts as their main source of nutrition. Our analyses also revealed a substantial presence of several Firmicutes within the foreguts and midguts of these shrimps, which closest known lineages were systematically digestive epibionts associated with alvinocaridids, and more broadly from digestive systems of other crustaceans from marine and terrestrial ecosystems. Overall, our study opens new perspectives not only about chemosynthetic symbioses of vent shrimps, but more largely about digestive microbiomes with potential ancient and evolutionarily conserved bacterial partnerships among crustaceans.

Spectrum of $^7$Li and elastic scattering reaction $^4$He($^3$H, $^3$H)$^4$He are studied using the unified description of the Gamow shell model in the coupled-channel formulation (GSMCC). The reaction channels are constructed using the cluster expansion with the two mass partitions [$^4$He + $^3$H], [$^6$Li + n]., Comment: 10 pages, 3 figures. Presented at Zakopane 2022 Conference on Nuclear Physics

17 pages; International audience; Kelp forests dominated by Macrocystis pyrifera are widely distributed in coastal waters from boreal, temperate and subantarctic regions. This widespread distribution may result in regional differences in food web structure and functioning. In temperate northern regions, where most studies on kelp forest benthic food webs have been conducted, kelp grazing is a well-documented phenomenon and can lead to the overgrazing of M. pyrifera by sea urchins when their predators (e.g., sea otters) are absent. In contrast, little is known about their counterparts in subantarctic areas. The present study aimed to reconstruct the benthic food web of a kelp forest dominated by M. pyrifera in a subantarctic environment using stable isotope analysis. Stable carbon (δ13C), nitrogen (δ15N) and sulfur (δ34S) isotope ratios were measured from food sources (macrophytobenthos, suspended particulate organic matter SPOM, and sediment) and consumers (sponges, bivalves, gastropods, sedentary and mobile polychaetes, arthropods and echinoderms) which were sampled in a kelp forest of the Kerguelen archipelago. Mixing models highlighted two interconnected trophic pathways which were either supported by SPOM and resuspended macrophytobenthos detritus (bentho-pelagic), or by live micro/macrophytobenthos (phytobenthos-based). No major prey were highlighted for several consumers, indicating the existence of potential supplementary trophic pathways. No consumer relying primarily on living M. pyrifera was highlighted by the mixing models. The investigated kelp forest is hence a complex ecosystem supporting multiple trophic pathways, and direct consumption of M. pyrifera is limited. Nonetheless, M. pyrifera and other macrophytobenthos species may constitute a pool of detritus supporting several trophic pathways.

To date, two main vent faunal assemblages have been described on active sulfide edifices along the northern Mid-Atlantic Ridge (nMAR): one dominated by bathymodiolin mussels in low temperature areas and the other dominated by alvinocaridid shrimp in warmer habitats. In this study, we describe the ecology of new types of assemblage, dominated by gastropods, that are recurrent in several nMAR vent fields, from ~830 m to 3500 m depth. We assessed and compared the composition, abundance, diversity and trophic niche of these assemblages from three vent fields (Menez Gwen, Lucky Strike and Snake Pit) and characterized their habitats in terms of key environmental conditions. These assemblages, first seen during the Momarsat cruise in 2012 at the Lucky Strike vent field, were investigated during several subsequent cruises. They appear to be widespread along the nMAR, forming two distinct assemblages, one dominated by Lepetodrilus atlanticusat the shallowest vent field Menez Gwen, and the other by Peltospira smaragdina at the other investigated fields. Our data seem to indicate that these gastropods dominate an intermediate habitat at MAR vents and may play an important ecological role in these communities.

Spectroscopic factors involving well bound nucleons in light nuclei are calculated with standard shell model, no-core shell model and Gamow shell model. Continuum coupling is included exactly in the Gamow shell model, due to the use of the Berggren basis, which contains bound, resonance and scattering states. Conversely, it is absent from standard and no-core shell models, where a basis of harmonic oscillator states is used. As the A−1 nuclei for which spectroscopic factors are calculated are either weakly bound or unbound, coupling to continuum is prominent, even though the A nuclei are well bound. It is then showed that Gamow shell model can properly reproduce experimental data and is a predictive tool for detailed nuclear structure at drip-line, contrary to standard and no-core shell model.

Alzheimer's disease (AD) is a common neurodegenerative disease that leads to memory and cognitive impairment. Exercise is suggested to prevent it. However, the exact mechanism remains unclear. This study investigated the effect of moderate exercise on cognitive function, oxidative stress and neuro-inflammation in the hippocampal tissue of experimentally-induced AD rats and the possible role of Nuclear Factor Erythroid 2- Related Factor 2 (NRF2) in mediating this effect. Forty adult male albino rats were divided into control and AD groups. Each group is further subdivided into sedentary and exercised ones. AD was induced by intraperitoneal injection with aluminium chloride (70 mg/kg b.w.) for 6 weeks. Exercise protocol was done by swimming 60 min, 5 times a week for 4 weeks. The following parameters were evaluated in all groups: hippocampal tissue assessment of NRF2, amyloid beta, malondialdehyde, interleukin 6 and total antioxidant capacity. Assessment of cognitive performance was done using Morris water maze at weeks 3, 4 and 6 after AD induction. Results revealed significantly lower hippocampal NRF2 and TAC levels with significant higher Aβ, MDA, IL-6 and impaired cognitive dysfunction in sedentary AD rats. These were reversed by swimming exercise. NRF2 was negatively correlated with Aβ, IL-6 and MDA in both AD groups with positive correlation with TAC. In conclusion, moderate swimming exercise exerts neuroprotective effects in AD through improvement of cognitive function, restoration of the antioxidant and anti-inflammatory capacity. The upregulation of NRF2 could mediate these effects. Therefore, targeting NRF2 could be promising as a therapeutic agent for neurodegenerative diseases.

Abstract Here we report the discovery of a high-temperature hydrothermal vent field on the Woodlark Ridge, using ship-borne multibeam echosounding and Remotely Operated Vehicle (ROV) exploration. La Scala Vent Field comprises two main active areas and several inactive zones dominated by variably altered basaltic rocks, indicating that an active and stable hydrothermal circulation has been maintained over a long period of time. The Pandora Site, at a depth of 3380 m, is mainly composed of diffuse vents. The Corto site, at a depth of 3360 m, is characterized by vigorous black smokers (temperature above 360 °C). The striking features of this new vent field are the profusion of stalked barnacles Vulcanolepas sp. nov., the absence of mussels and the scarcity of the gastropod symbiotic fauna. We suggest that La Scala Vent Field may act as a dispersing centre for hydrothermal fauna towards the nearby North Fiji, Lau and Manus basins.

Funding Acknowledgements Type of funding sources: None. Background Despite the increasing number of studies concerning Left Atrial Strain (LAS), few data are available comparing LAS patients with cardiac amyloidosis (CA) and sarcomeric hypertrophic cardiomyopathies (HCM). Purposes We aimed to perform a comparative multimodal imaging analysis of LAS of a prospective cohort of patients with CA and HCM. Methods For each enrolled patient, we performed same-day two and three-dimension echocardiography (TTE) and cardiac magnetic resonance imaging (CMR) to blindly measure the peak atrial longitudinal strain (PALS) and the peak atrial contraction strain (PACS). Patients with acute atrial fibrillation were excluded. Results Between January 2020 and July 2021, 67 patients were included: 31 patients with CA (age 75.1 ± 10 years, left ventricular ejection fraction 60.6 ± 10.4%, maximum left ventricular thickness 17.8 ± 3.9 mm) and 36 with HCM (age 50.8 ± 15.5 years, left ventricular ejection fraction 66.1 ± 9.8%, maximum left ventricular thickness 20.7 ± 4.5 mm). Left atrial volume was similar in the 2 groups (42.5 ± 15.6 mL/m2 in HCM vs 47.9 ± 15 in CA, P = 0.1557). Concerning PALS, its values for CA and for CMH were on 2D TTE manual (10.9 ± 5.8% vs 21.4 ± 9.4%, P Concerning PACS, its values for CA and for CMH were on 2D TTE manual (5.2 ± 3.4% vs 10 ± 4%, P Multivariate analysis adjusted on main factors influencing LAS (left ventricular (LV) mass, LV ejection fraction, LV global longitudinal strain, renal function and history of hypertension) found that the differences between the two groups remained significant for PALS and PACS for almost all technics. Furthermore, although concordance between the 3 echocardiographic technics was excellent (the interclass correlation coefficient (ICC) was higher than 0.80 between each TTE methods), ICC was poor between TTE and CMR technics: 0.40 (0.18-0.59) for manual 2D TTE and CMR, 0.46 (0.24-0.63) for auto 2D TTE and CMR, 0.40 (0.14-0.60) for 3D TTE and CMR. Conclusion Our study is the first to describe and compare, both on TTE and CMR, LAS on a prospective cohort of patients with CA and HCM. Although they have same mean left atrial volume, we found significant differences on PALS and PACS between these two groups of patients on all the studied technics. These findings may be used in future multi-modality imaging studies dealing with diagnosis or prognosis of these hypertrophic cardiopathies. Abstract Figure. LAS 2D TTE manual Abstract Figure. LAS comparison between CA and HCM

Although they are part of the lightest nuclei, the hydrogen isotopes are not well understood both experimentally and theoretically. Indeed, besides deuteron and triton, all known hydrogen isotopes are resonances of complex structure. Even more elusive is 7H, which may have been observed experimentally and has been claimed to be a narrow resonance. Nevertheless, even its existence is controversial, and its theoretical study is difficult due to both its unbound character and large number of interacting valence nucleons. It is then the object of this paper to theoretically study the hydrogen isotopes {4-7}H with the Gamow shell model, which is, up to our knowledge, the first direct calculation of unbound resonance hydrogen isotopes up to 7H. As the Gamow shell model includes both continuum coupling and inter-nucleon correlations, useful information can be obtained about poorly known unbound hydrogen isotopes. Our present calculations indicate that {4,6}H ground states are fairly broad resonances, whereas those of {5,7}H are narrow, which is in accordance with current experimental data. The results then suggest that, in particular, {5,7}H should be more heavily studied, as they might well be among the most narrow neutron resonances of the light nuclear chart.

Sea stars (Echinodermata: Asteroidea) are a key component of Southern Ocean benthos, with 16% of the known sea star species living there. In temperate marine environments, sea stars commonly play an important role in food webs, acting as keystone species. However, trophic ecology and functional role of Southern Ocean sea stars are still poorly known, notably due to the scarcity of large-scale studies. Here, we report 24332 trophic marker (stable isotopes and elemental contents of C, N and S of tegument and/or tube feet) and biometric (arm length, disk radius, arm to disk ratio) measurements in 2456 specimens of sea stars. Samples were collected between 12/01/1985 and 08/10/2017 in numerous locations along the Antarctic littoral and Subantarctic islands. The spatial scope of the dataset covers a significant portion of the Southern Ocean (Latitude: 47.717° South to 86.273° South; longitude: 127.767° West to 162.201° East; depth: 6 to 5338 m). The dataset contains 133 distinct taxa, including 72 currently accepted species spanning 51 genera, 20 families and multiple feeding guilds / functional groups (suspension feeders, sediment feeders, omnivores, predators of mobile or sessile prey). For 505 specimens, mitochondrial CO1 genes were sequenced to confirm and/or refine taxonomic identifications, and those sequences are already publicly available through the Barcode of Life Data System. This number will grow in the future, as molecular analyses are still in progress. Overall, thanks to its large taxonomic, spatial, and temporal extent, as well as its integrative nature (combining genetic, morphological and ecological data), this dataset can be of wide interest to Southern Ocean ecologists, invertebrate zoologists, benthic ecologists, and environmental managers dealing with associated areas. Please cite this data paper in research products derived from the dataset, which is freely available without copyright restrictions.

We have applied the Gamow shell model to calculate nuclear observables of $^{26-31}$Ne isotopes pertaining to one-neutron halo structure, these nuclei being situated close to neutron drip-line. As both many-body correlations and continuum coupling are taken into account in that approach, halo structure can be analyzed properly. Our calculations provide good descriptions of $^{26-31}$Ne, where asymptotic behavior is crucial for that matter. One-body density, neutron root-mean-square radii of $^{26-31}$Ne, and one-neutron overlap functions of $^{29,31}$Ne have been calculated as well. Our results support the presence of a one-neutron \textit{p}-wave halo in $^{31}$Ne, already pointed out experimentally. A similar situation also occurs in the ground state of $^{29}$Ne, which is mainly a \textit{p}-wave valence neutron coupled to the inner $^{28}$Ne \textit{core}. The $3/2^+$ excited state of $^{29}$Ne, which is dominated by a \textit{d}-wave valence neutron, has also been considered. A larger radius and more extended wave function occur for the ground state of $^{29}$Ne when compared to its $3/2^+$ first excited state. The present results suggest that $^{29}$Ne is a good candidate for one-neutron \textit{p}-wave halo in the medium-mass region., Comment: 7 Pages, 3 Figures

^{18}Mg was observed, for the first time, by the invariant-mass reconstruction of ^{14}O+4p events. The ground-state decay energy and width are E_{T}=4.865(34) MeV and Γ=115(100) keV, respectively. The observed momentum correlations between the five particles are consistent with two sequential steps of prompt 2p decay passing through the ground state of ^{16}Ne. The invariant-mass spectrum also provides evidence for an excited state at an excitation energy of 1.84(14) MeV, which is likely the first excited 2^{+} state. As this energy exceeds that for the 2^{+} state in ^{20}Mg, this observation provides an argument for the demise of the N=8 shell closure in nuclei far from stability. However, in open systems this classical argument for shell strength is compromised by Thomas-Ehrman shifts.

Single-nucleon knockout reaction studies of the proton-dripline nuclei $^9$C and $^{13}$O suggest an appreciable suppression of spectroscopic factors. In this work, we calculate the one-neutron and one-proton spectroscopic factors for the mirror pair $^9$C-$^9$Li and $^{13}$O using two variants of the continuum shell model: the complex-energy Gamow Shell Model and the real-energy Shell Model Embedded in the Continuum. Our results indicate that the continuum effects strongly suppress the spectroscopic factors of well-bound orbits in the dripline systems, but have less impact on the spectroscopic factors of weakly-bound states., 7 pages, 3 figures, 1 table

Cet article examine les contributions de Dalal (2019) et de Samuels (2019), qui explorent les tensions entre l’individu et le groupe, les complexites des dynamiques de pouvoir et de responsabilite personnelle dans un groupe, ainsi que le concept de croissance personnelle ou de maturation. Autant d’elements que cet article considere comme une consequence de l’interjeu entre l’individu et les processus sociaux.

A kinematically complete quasi-free $(p,pn)$ experiment in inverse kinematics was performed to study the structure of the Borromean nucleus $^{17}$B, which had long been considered to have neutron halo. By analyzing the momentum distributions and exclusive cross sections, we obtained the spectroscopic factors for $1s_{1/2}$ and $0d_{5/2}$ orbitals, and a surprisingly small percentage of 9(2)$\%$ was determined for $1s_{1/2}$. Our finding of such a small $1s_{1/2}$ component and the halo features reported in prior experiments can be explained by the deformed relativistic Hartree-Bogoliubov theory in continuum, revealing a definite but not dominant neutron halo in $^{17}$B. The present work gives the smallest $s$- or $p$-orbital component among known nuclei exhibiting halo features, and implies that the dominant occupation of $s$ or $p$ orbitals is not a prerequisite for the occurrence of neutron halo., Accepted for publication in Physical Review Letters,8 pages, 4 figures

Groups are arguably an essential and unavoidable part of our human lives—whether we are part of families, work teams, therapy groups, organizational systems, social clubs, or larger communities. In Groups in Transactional Analysis, Object Relations, and Family Systems: Studying Ourselves in Collective Life, N. Michel Landaiche, III addresses the intense feelings and unexamined beliefs that exist in relation to groups, and explores how to enhance learning, development and growth within them. Landaiche’s multidisciplinary perspective is grounded in the traditions of Eric Berne’s transactional analysis, Wilfred Bion’s group-as-a-whole model, and Murray Bowen’s family systems theory. The book presents a practice of studying ourselves in collective life that utilizes a naturalistic method of observation, analysis of experiential data, and hypothesis formation, all of which are subject to further revision as we gather more data from our lived experiences. Drawing from his extensive professional experience of group work in a range of contexts, Landaiche deftly explores topics including group culture, social pain, learning and language, and presents key principles which enhance and facilitate learning in groups. With a style that is both deeply personal and theoretically grounded in a diverse range of studies, Groups in Transactional Analysis, Object Relations, and Family Systems presents a contemporary assessment of how we operate collectively, and how modern life has changed our outlook. It will be essential reading for transactional analysts in practice and in training, as well as other professionals working with groups. It will also be of value to academics and students of psychology, psychotherapy, and group dynamics, and anyone seeking to understand their role within a group. See the below link to an interview about the book with Tess Elliott: https://vimeo.com/510266467

Among hydrothermal vent species, Rimicaris exoculata is one of the most emblematic, hosting abundant and diverse ectosymbioses that provide most of its nutrition. Rimicaris exoculata co-occurs in dense aggregates with the much less abundant Rimicaris chacei in many Mid-Atlantic Ridge vent fields. This second shrimp also houses ectosymbiotic microorganisms but has a mixotrophic diet. Recent observations have suggested potential misidentifications between these species at their juvenile stages, which could have led to misinterpretations of their early-life ecology. Here, we confirm erroneous identification of the earliest stages and propose a new set of morphological characters unambiguously identifying juveniles of each species. On the basis of this reassessment, combined use of C, N and S stable isotope ratios reveals distinct ontogenic trophic niche shifts in both species, from photosynthesis-based nutrition before settlement, towards a chemosynthetic diet afterwards. Furthermore, isotopic compositions in the earliest juvenile stages suggest differences in larval histories. Each species thus exhibits specific early-life strategies that would, without our re-examination, have been interpreted as ontogenetic variations. Overall, our results provide a good illustration of the identification issues persisting in deep-sea ecosystems and the importance of integrative taxonomy in providing an accurate view of fundamental aspects of the biology and ecology of species inhabiting these environments.

Among hydrothermal vent species, Rimicaris exoculata is one of the most emblematic, hosting abundant and diverse ectosymbioses that provide most of its nutrition. Rimicaris exoculata co-occurs in dense aggregates with the much less abundant Rimicaris chacei in many Mid-Atlantic Ridge vent fields. This second shrimp also houses ectosymbiotic microorganisms but has a mixotrophic diet. Recent observations have suggested potential misidentifications between these species at their juvenile stages, which could have led to misinterpretations of their early-life ecology. Here, we confirm erroneous identification of the earliest stages and propose a new set of morphological characters unambiguously identifying juveniles of each species. On the basis of this reassessment, combined use of C, N and S stable isotope ratios reveals distinct ontogenic trophic niche shifts in both species, from photosynthesis-based nutrition before settlement, towards a chemosynthetic diet afterwards. Furthermore, isotopic compositions in the earliest juvenile stages suggest differences in larval histories. Each species thus exhibits specific early-life strategies that would, without our re-examination, have been interpreted as ontogenetic variations. Overall, our results provide a good illustration of the identification issues persisting in deep-sea ecosystems and the importance of integrative taxonomy in providing an accurate view of fundamental aspects of the biology and ecology of species inhabiting these environments.

The model of Paricaud (2011) has previously been shown to be able to accurately correlate the three-phase equilibrium conditions of TBAB semi-clathrates in the presence of pure CO2. While the model of Paricaud (2011) was derived in a manner that was expected to make it relatively straight forward correlating the three-phase equilibrium conditions of semi-clathrates in the presence of mixed gases this capability has not, at the time of writing, been tested. In the present work, the model of Paricaud (2011), along with the modification of Garcia et al. (2016), is examined for its ability to correlate the three-phase equilibrium conditions of TBAB semi-clathrates formed in the presence of binary mixtures of (CO2 + N2), (CO2 + H2), (CO2 + CH4), and (CO2 + CO) and in the presence of a ternary mixture of (CO2 + H2+CO). The computations were carried out at temperatures between (281 and 293) K, at pressures between (2.0 and 6.6) MPa and in aqueous TBAB solutions of wTBAB = (0.05, 0.10, and 0.20). The average absolute relative deviation of the correlations ranged from 3.7%, for TBAB semi-clathrates formed in the presence of an equimolar mixture of (CO2 + N2), to 7.1%, for TBAB semi-clathrates formed in the presence of a ternary gas mixture of (CO2 + H2+CO).

Colorectal cancer (CRC) is a common worldwide cancer associated with different genetic changes. The present study aimed to elucidate the possible crosstalk between colorectal cancer-derived non-coding RNAs (ncRNAs), tumor mitochondrial biogenesis, and macrophage polarization in colorectal cancer patients. Fresh tumor tissue samples with adjacent normal tissues were obtained from 62 CRC patients, quantitative real-time PCR (qRT-PCR) was used to detect the tissue expression of long non-coding RNAs (lncRNAs) such as PTENP1, H19, XIST, MALAT1, and HOTAIR as well as microRNA ((miR-133a)), mitochondrial markers as mtDNA copy number and Uncoupling protein 2 (UCP2), macrophage markers (INOS, CD80 and CD163) and other genes as TGFβRII and NRF-2. The expression levels of the 5 studied lncRNAs were upregulated in CRC tissues compared to the adjacent non-cancer tissues. HOTAIR expression was negatively correlated with CD80 (M1-polarization marker) and positively correlated with CD163 (M2-polarization marker) while miR-133a showed opposite association with these macrophage markers. Non-significant increase was observed in the tumor mtDNA copy number which showed a positive correlation with XIST. Moreover, a significant positive correlation was shown between CD163 and UCP2 expressions. Furthermore, TGFβRII expression was directly correlated with some lncRNAs (PTENP1, MALAT1, and HOTAIR) and tumor mtDNA copy number. The study highlighted significant crosstalk between ncRNA (HOTAIR and miR-133a) and M2-polarization. The obtained data suggest the potential roles of HOTAIR, miR-133a, UCP2 and TGFβRII in the development of CRC, suggesting their possible diagnostic and therapeutic potentials in CRC.

Introduction Le dosage des IgE specifiques represente une etape importante dans le diagnostic des allergies de type I. L’un des systemes les plus couramment utilises et valides pour ce dosage est le systeme ImmunoCAP®. Nous avons evalue les resultats obtenus avec le systeme NOVEOS® puis les avons compare a l’ImmunoCAP®, dans une cohorte de patients souffrant d’allergies respiratoires et alimentaires. Methodes L’etude a ete conduite au CHU de Montpellier, France, en 2020. Pour evaluer le systeme NOVEOS®, nous avons realise une etude de precision de 5 jours et un test LoB/LOQ. Nous avons ensuite compare les resultats obtenus en utilisant les deux systemes differents, en evaluant la concordance relative et avec une analyse Passing Bablok. Nous avons realise l’etude sur des echantillons de 82 patients mono-sensibilises. Les allergenes evalues comprenaient : Dermatophagoides pteronyssinus (D001), Der p 1 (D202), squames de chat (E001), Phleum pratense (G006), Phl p 1 (G205), Juniperus sabinoides (T006), arachide (F013), rAra h 2 (F423). Resultats Au cours de l’evaluation, des ecarts ont ete observes dans les performances du NOVEOS® aux jours 1 a 3. Le systeme a ete realigne et a subi une mise a jour. Il y avait un intervalle d’un mois entre les jours 5 et 6 de l’evaluation. Les resultats des analyses des jours 6 a 10 ont montre que, a l’exception de deux echantillons, tous les resultats presentaient des coefficients de variations entre 3,7 % et 8,7 %. L’analyse LoQ a montre que tous les allergenes testes presentaient une LoQ inferieure a 0,17 kUA/L, qui est la LoQ presentee dans l’insert directionnel du fabricant. Lors de la comparaison des resultats du systeme NOVEOS® et de l’ImmunoCAP®, la concordance positive de sensibilite etait de 89,86 %, tandis que la concordance negative de specificite etait de 100 %. La correlation evaluee par une analyse Passing Bablok a montre un r = 0,782. Conclusion Nos resultats suggerent que les performances du systeme NOVEOS® sont comparables a celle de l’ImmunoCAP® pour tous les allergenes evalues. Le NOVEOS® repond donc aux criteres de dosage d’IgE seriques specifiques en milieu clinique et de laboratoire, avec des echantillons de seulement 4 ml au lieu de 40 ml.

Introduction La Polyarthrite Rhumatoïde (PR) est le plus fréquent des rhumatismes inflammatoires chroniques. Le facteur rhumatoïde (FR) est très fréquemment positif dans la PR (70 à 80 %), sans être spécifique de cette pathologie puisqu’il s’observe dans d’autres pathologies auto-immunes, infectieuses ou hématologiques (Ingegnoli - 2013). Il est probable que les différents éléments à l’origine de faux positifs lors des tests sérologiques visant SARS-CoV, en particulier la présence d’auto-anticorps dont le FR, soit aussi à l’origine de faux positifs lors de la réalisation de tests sérologiques visant le SARS-CoV-2. Ce projet a pour but de valider et d’optimiser les tests diagnostiques sérologiques COVID-19 pour pouvoir mieux interpréter les faux positifs dans cette population particulière de patients avec FR positif, afin de choisir le test idéal pour minimiser les faux positifs. Matériels et méthodes Étude rétrospective. 265 sérums des échantillons des patients atteints de PR prélevé avant 07/2019 pour assurer la vraie négativité au Covid-19 ont été inclus et répartis en 2 groupes Groupe 1(G1) : PR séropositive pour le FR+ et Groupe 2 (G2) : PR séronégative pour le FR- Une analyse de FR et de ses sous-types de FR (IgM et IgA) a été réalisé pour évaluer l’influence sur la spécificité des 3 différents tests sérologiques du SARS-CoV-2(UNscience, SureScreen, iSIA) disponibles pour la détection des IgG et IgM spécifiques et l’analyse ELISA de SARS-CoV-2. Résultats G1 : n = 210 ; G2 : n = 55. Résultats : G1 : UNscience : spécificité : 91 % (taux de faux positifs : 9,0 %) ; SureScreen : spécificité : 92 % (taux de faux positifs : 7,6 %) ; iSIA : spécificité : 58 % (taux de faux positifs : 44,3 %) ; ELISA : spécificité : 99 % (taux de faux positifs : 1,0 %) G2 : UNscience : spécificité : 98 % (taux de faux positifs : 1,8 %) ; SureScreen : spécificité : 96 % (taux de faux positifs : 3,6 %) ; iSIA : spécificité : 91 % (taux de faux positifs : 9,1 %) ; ELISA : spécificité : 98 % (taux de faux positifs : 1,8 %). Les sous-types de FR associé à la fausse positivité du test : Unscience IgA ; iSIA IgA et IgM ; SureScreen. Discussion Si on compare les patients PR en fonction de la positivité du FR et selon la positivité des IgM et/ou des IgA, le taux de faux positifs SARS-CoV-2 est significativement supérieur dans le groupe FR positif si les IgA et les IgM sont positives. Les analyses stratifiées confrontant respectivement les taux d’IgM et d’IgA ont montré que la proportion des faux positifs avec le test iSIA augmentait avec les taux d’IgA et d’IgM. La spécificité du test iSIA est fortement influencée par la présence du FR, raison pour laquelle ce test ne devrait pas être un choix de test sérodiagnostic du SARS-CoV-2 pour cette poblation. Conclusion Si on compare chacun de 3 test sérodiagnostic du SARS-CoV-2 rapides et le test Elisa chez des patients porteurs de FR on observe un taux de faux positifs significativement supérieur avec le test iSIA comme en témoigne un taux de faux positifs significativement plus élevé avec le FR positif (44,3 %) que parmi les sérums FR négatif (9,5 %). Pour pouvoir mieux interpréter un résultat de sérologie SARS-Cov2, il faut tenir compte de la positivité du FR. Le test ELISA parait le plus approprié.

This paper presents performances achieved with InAlGaN/GaN HEMTs with 0.15 µm gate length on SiC substrate. Technology Computer Aided Design simulations were used to optimize the heterostructure. Special attention was paid to the design of the buffer structure. I-V measurements with DC and pulsed bias voltages were performed. CW measurements at millimeter waves were also carried out and are detailed in the following sections. The technology, optimized for power applications up to 45 GHz, demonstrates a current gain cut-off frequency FTof 70 GHz and a maximum available gain cut-off frequency FMAGof 140 GHz. CW Load-pull power measurements at 30 GHz enable to achieve a maximum PAE of 41% associated with an output power density of 3.5 W/mm when biased at VDS= 20 V. These devices, with an improved buffer structure show, reduced recovery time in pulsed operating conditions. These improved characteristics should have a positive impact for pulsed or modulated signal applications.

Silicon drift detectors have been successfully employed in both soft and hard X-ray spectroscopy. The response function to incident radiation at soft X-ray levels has been well studied and modeled, but less research has been published on response functions for these detectors to hard X-ray input spectra above 20 keV. When used with hard X-ray sources a significant low energy, non-peak response exists which can adversely affect detection limits for lighter elements in, for example, X-ray fluorescence spectroscopy. We present a numerical model that explains the non-peak response function of silicon drift detectors to hard X-rays based on incoherent Compton scattering within the detector volume. Experimental results are presented and numerically compared to model results.

Myotonic Dystrophy type 1 (DM1) is caused by an expansion of CUG repeats in DMPK mRNAs. This mutation affects alternative splicing through misregulation of RNA-binding proteins. Amongst pre-mRNAs that are mis-spliced, several code for proteins involved in calcium homeostasis suggesting that calcium-handling and signaling are perturbed in DM1. Here, we analyzed expression of such proteins in DM1 mouse muscle. We found that the levels of several sarcoplasmic reticulum proteins (SERCA1, sarcolipin and calsequestrin) are altered, likely contributing to an imbalance in calcium homeostasis. We also observed that calcineurin (CnA) signaling is hyperactivated in DM1 muscle. Indeed, CnA expression and phosphatase activity are both markedly increased in DM1 muscle. Coherent with this, we found that activators of the CnA pathway (MLP, FHL1) are also elevated. Consequently, NFATc1 expression is increased in DM1 muscle and becomes relocalized to myonuclei, together with an up-regulation of its transcriptional targets (RCAN1.4 and myoglobin). Accordingly, DM1 mouse muscles display an increase in oxidative metabolism and fiber hypertrophy. To determine the functional consequences of this CnA hyperactivation, we administered cyclosporine A, an inhibitor of CnA, to DM1 mice. Muscles of treated DM1 mice showed an increase in CUGBP1 levels, and an exacerbation of key alternative splicing events associated with DM1. Finally, inhibition of CnA in cultured human DM1 myoblasts also resulted in a splicing exacerbation of the insulin receptor. Together, these findings show for the first time that calcium-CnA signaling is hyperactivated in DM1 muscle and that such hyperactivation represents a beneficial compensatory adaptation to the disease.

This article presents the performances obtained on a $0.15 \mu \mathrm{m}$ gate length InAlGaN/GaN HEMT technology on SiC substrate. This technology uses a back-barrier buffer layer to ensure the confinement of electrons in the channel, which minimizes variations of the drain current when the HEMT devices are submitted to DC or RF pulses. Measurements of the drain current recovery time are shown when the devices are submitted to V DS , V GS or microwave RF pulses. A comparison with an AlGaN/GaN HEMT structure designed with an iron doped buffer layer is proposed.

This paper presents the measurement results of a MMIC power amplifiers (PA), based on InAlGaN/GaN HEMT technology, for Ka band applications. The three-stages MMIC is operating within a bandwidth of [25-31] GHz and demonstrate over this bandwidth a saturated output power of 40dBm. Each stage uses 8x50μm gate width HEMTs fabricated with a 0.I5μm gate length on 70μm thick SiC substrate.

International audience; This paper reports on atomic layer etching of several III-N materials such as GaN, AlN, AlGaN, and InAlGaN based on a sequential surface modification by chlorine adsorption followed by a low energy Ar plasma exposure to remove the modified layer using a reactive ion etching system. A study on the influence of several parameters, such as gas flow rates, removal step duration, RIE power and number of cycles on the etch per cycle, and the root-mean-square roughness, is performed. Low etch per cycle from 0.17 to 1.85 nm/cycle, respectively, for AlGaN and GaN and surfaces as smooth as the as-grown samples were obtained. The developed process is intended to be used for normally off GaN-based high electron mobility transistor processing.