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We have experimentally determined the production rate of $^{39}$Ar and $^{37}$Ar from cosmic ray neutron interactions in argon at sea level. Understanding these production rates is important for argon-based dark matter experiments that plan to utilize argon extracted from deep underground because it is imperative to know what the ingrowth of $^{39}$Ar will be during the production, transport, and storage of the underground argon. These measurements also allow for the prediction of $^{39}$Ar and $^{37}$Ar concentrations in the atmosphere which can be used to determine the presence of other sources of these isotopes. Through controlled irradiation with a neutron beam that mimics the cosmic ray neutron spectrum, followed by direct counting of $^{39}$Ar and $^{37}$Ar decays with sensitive ultra-low background proportional counters, we determined that the production rate from cosmic ray neutrons at sea-level is expected to be $(759 \pm 128)$ atoms/kg$_\text{Ar}$/day for $^{39}$Ar, and $(51.0 \pm 7.4)$ atoms/kg$_\text{Ar}$/day for $^{37}$Ar. We also performed a survey of the alternate production mechanisms based on the state-of-knowledge of the associated cross-sections to obtain a total sea-level cosmic ray production rate of $(1048 \pm 133)$ atoms/kg$_\text{Ar}$/day for $^{39}$Ar, $(56.7 \pm 7.5)$ atoms/kg$_\text{Ar}$/day for $^{37}$Ar in underground argon, and $(92 \pm 13)$ atoms/kg$_\text{Ar}$/day for $^{37}$Ar in atmospheric argon., Comment: 13 pages, 9 figures, 6 tables; Minor updates to systematic uncertainty evaluation, formatting

Objective To provide an overview of the technical aspects and potential clinical applications of microvessel perfusion as depicted by microbubble-enhanced sonography. Methods Sonographic depiction of microvessel perfusion was obtained by microbubble-enhanced sonography. This technique was used for imaging in vivo murine tumors and was correlated with magnetic resonance and fluorodeoxyglucose autoradiography. Sonographic estimation of microvessel perfusion used parameters derived from time-activity curves. Results Preliminary data indicate that accurate and reproducible quantification of microvessel perfusion is possible with the use of microbubble-enhanced sonography. Conclusions Microbubble-enhanced sonography can depict microvessel perfusion. This technique has several potential clinical applications, including assessment of tumor blood flow and changes that occur with treatment.

Différentes espèces phytoplanctoniques ont été à l'origine d'efflorescences toxiques sur l'ensemble du littoral français ces dernières années. Parmi celles-ci, les efflorescences de l'espèce Alexandrium minutum s'avèrent comme particulièrement dangereuses. Cette espèce produit des toxines paralysantes responsables chez l'homme du syndrome PSP ("Paralytic Shellfish Poisoning"). Les incidences des eaux colorées pour les activités économiques se traduisent par des interdictions préfectorales de commercialisation et de ramassage des mollusques filtreurs pouvant entraîner des pertes financières non négligeables pour les professionnels (ostréiculteurs, mytiliculteurs, ... ) ainsi qu'un préjudice sur l'image de marque des zones contaminées pour la fréquentation touristique. La présence en France d'Alexandrium minutum dans les eaux côtières n'a été signalée que très récemment : elle a été observée pour la première fois en rivière de Penzé en juin 1988 puis dans les abers (Aber Wrac'h et Aber Benoit) en août 1988. L'espèce tend à se disséminer et sa présence a été relevée ces dernières années en Baie de Lannion, dans la Rance et en Baie de Vilaine. Récemment, sa présence a également été signalée dans le bassin de Marennes-Oléron et dans la Rade de Toulon. Les conditions de prolifération de l'espèce demeurent encore très mal connues. Son développement sur les côtes bretonnes semble restreint aux estuaires et aux baies aquacoles soumis à des apports anthropiques accentués ; l'enrichissement des eaux côtières en éléments nutritifs (azote, phosphore) voire en d'autres espèces chimiques (métaux, matières organiques, ... ) pourraient favoriser son développement jusqu'au stade d'eaux colorées toxiques. Cependant, l'incidence exacte de ces apports sur le développement de cette algue n'est qu'imparfaitement connue : ainsi dans l'Étang de Thau, malgré une politique de réduction importante des apports anthropiques, une espèce « analogue » (Alexandrium tamarense) est apparue en fortes concentrations en 1998. La Baie de Morlaix, réceptacle de rejets agricoles et urbains importants, apparaît actuellement comme un site fortement colonisé par Alexandrium minutum. Des efflorescences sont relevées régulièrement chaque année dans l'estuaire de la Penzé et de la Rivière de Morlaix. La présence de formes de résistance de l'espèce dans le sédiment a été établie ; si la répartition des kystes et leur confinement dans l'estuaire sont bien documentés (Érard-Le Denn et al., 1993), les facteurs qui déclenchent leur germination in situ restent par contre pour le moment mal définis. La prolifération de l'espèce dans la colonne d'eau suppose l'établissement de conditions favorables qu'il est nécessaire de cerner avant d'envisager une prévention et une meilleure gestion des épisodes toxiques. Le développement d'Alexandrium minutum (comme pour toute espèce phytoplanctonique) est lié à des facteurs physiques (température, salinité, lumière) et à des facteurs nutritionnels (azote, phosphore, métaux traces, matière organique, ... ). L'accumulation des cellules créant des eaux colorées en surface (figure 1) dépend également de la croissance nette de la population et du comportement des cellules. Cette algue croît dans un contexte biologique qu'il est aussi nécessaire d'étudier, en particulier en ce qui concerne les espèces accompagnatrices. Comme le développement de l'espèce est restreint à des systèmes nettement perturbés par les apports anthropiques, l'hypothèse d'une modification des facteurs nutritionnels favorisant la floraison d'Alexandrium minutum doit être examinée.

International audience; The C70 ARRONAX is a high intensity (up to 2x375uA) multi-particle cyclotron aiming at R&D on material and radiolysis and production of radioisotopes. It began its hands-on phase in December 2010, and is currently undergoing beam lines' modification in experimental halls for present and future experiments. Characterisation of the beams at the end of beamlines is of particular importance to determine the capacity of the cyclotron for end-line experimental users. A program of beam characterisation is being performed based in one hand on dedicated diagnostics e.g. beam profilers, faraday cups, alumina foils and in the other hand on a series of Geant4 beam simulations. The out coming results of the measurements, along with the simulations, are detailed in this report for proton and alpha particle beams, as well as the future prospects of the characterisation program.

consultable à l'adresse suivante : http://archimer.ifremer.fr/doc/00197/30785/29143.pdf; International audience; To design a prototype for an Integrated Ocean Observing System (IOOS), at least three components are mandatory: a modeling platform, an in situ observing system and a structure to collect and to disseminate the information (e.g. database, website). The PREVIMER project followed this approach and in order to sustain model applications, PREVIMER has developed, funded and organized part of in situ observing networks in the Bay of Biscay and the Channel. For a comprehensive system, focus was addressed on fi xed platforms (MAREL MOLIT, MAREL Iroise, Island network and D4 for sediment dynamics), ships of opportunity (RECOPESCA program and FerryBoxes), and coastal profi lers (ARVOR-C/Cm). Each system is briefl y described and examples of scientifi c results obtained with corresponding data are highlighted to show how these systems contribute to solve scientifi c multidisciplinary issues from the coastal ocean dynamics to the biodiversity including pelagic and benthic habitats.

International audience; Clinical manifestations of COVID-19 caused by the new coronavirus SARS-CoV-2 are associated with age1,2. Adults develop respiratory symptoms, which can progress to acute respiratory distress syndrome (ARDS) in the most severe form, while children are largely spared from respiratory illness but can develop a life-threatening multisystem inflammatory syndrome (MIS-C)3-5. Here, we show distinct antibody responses in children and adults after SARS-CoV-2 infection. Adult COVID-19 cohorts had anti-spike (S) IgG, IgM and IgA antibodies, as well as anti-nucleocapsid (N) IgG antibody, while children with and without MIS-C had reduced breadth of anti-SARS-CoV-2-specific antibodies, predominantly generating IgG antibodies specific for the S protein but not the N protein. Moreover, children with and without MIS-C had reduced neutralizing activity as compared to both adult COVID-19 cohorts, indicating a reduced protective serological response. These results suggest a distinct infection course and immune response in children independent of whether they develop MIS-C, with implications for developing age-targeted strategies for testing and protecting the population.

We report the natural history, clinical manifestations, genetics, and immunohematological findings in 14 patients from 11 families with ARPC1B deficiency, delineating the spectrum of the disease that appears progressive and challenging to manage clinically.

Lam et al. characterize a novel hematological/autoinflammatory disorder due to a de novo recurrent missense mutation of CDC42. The authors use in silico, in vitro, and in vivo analyses to correlate the molecular mechanisms altering CDC42 function to the observed phenotype., Hemophagocytic lymphohistiocytosis (HLH) is characterized by immune dysregulation due to inadequate restraint of overactivated immune cells and is associated with a variable clinical spectrum having overlap with more common pathophysiologies. HLH is difficult to diagnose and can be part of inflammatory syndromes. Here, we identify a novel hematological/autoinflammatory condition (NOCARH syndrome) in four unrelated patients with superimposable features, including neonatal-onset cytopenia with dyshematopoiesis, autoinflammation, rash, and HLH. Patients shared the same de novo CDC42 mutation (Chr1:22417990C>T, p.R186C) and altered hematopoietic compartment, immune dysregulation, and inflammation. CDC42 mutations had been associated with syndromic neurodevelopmental disorders. In vitro and in vivo assays documented unique effects of p.R186C on CDC42 localization and function, correlating with the distinctiveness of the trait. Emapalumab was critical to the survival of one patient, who underwent successful bone marrow transplantation. Early recognition of the disorder and establishment of treatment followed by bone marrow transplant are important to survival., Graphical Abstract

The coupling between long and short structural wavelengths is here investigated by using two different modelling techniques. The first is based on standard Finite Element Approach and used as a reference, while the second is built by scaling only the FEA model of the component carrying the shorter waves. The physical domain belonging to this one was scaled while the related original damping loss factor was artificially increased to recover the original energy content. This procedure is known as ASMA, Asymptotical Scaled Modal Analysis and it was defined for reducing the computational effort needed for the simulation of a given structural problem at increasing values of the modal overlap factors. Here, two configurations taken from the specific literature were investigated: the structural dynamic response of two in-line rods and a beam coupled with a plate. The present simulation results highlight the limits and the advantages of ASMA in analysing this specific coupling. This work is aimed to the definition of a hybrid approach between deterministic and energy methods.