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Calcium wave dynamics in the embryonic mouse gut mesenchyme: impact on smooth muscle differentiation
No full textInternational audienceAbstract Intestinal smooth muscle differentiation is a complex physico-biological process involving several different pathways. Here, we investigate the properties of Ca 2+ waves in the developing intestinal mesenchyme using GCamp6f expressing mouse embryos and investigate their relationship with smooth muscle differentiation. We find that Ca 2+ waves are absent in the pre-differentiation mesenchyme and start propagating immediately following α-SMA expression. Ca 2+ waves are abrogated by Ca V 1.2 and gap-junction blockers, but are independent of the Rho pathway. The myosine light-chain kinase inhibitor ML-7 strongly disorganized or abolished Ca 2+ waves, showing that perturbation of the contractile machinery at the myosine level also affected the upstream Ca 2+ handling chain. Inhibiting Ca 2+ waves and contractility with Ca V 1.2 blockers did not perturb circular smooth muscle differentiation at early stages. At later stages, Ca V 1.2 blockers abolished intestinal elongation and differentiation of the longitudinal smooth muscle, leading instead to the emergence of KIT-expressing interstitial cells of Cajal at the gut periphery. Ca V 1.2 blockers also drove apoptosis of already differentiated, Ca V 1.2-expressing smooth muscle and enteric neural cells. We provide fundamental new data on Ca 2+ waves in the developing murine gut and their relation to myogenesis in this organ
MHONGOOSE: A MeerKAT nearby galaxy H I survey
No full textInternational audienceThe MHONGOOSE (MeerKAT H I Observations of Nearby Galactic Objects: Observing Southern Emitters) survey maps the distribution and kinematics of the neutral atomic hydrogen (H I) gas in and around 30 nearby star-forming spiral and dwarf galaxies to extremely low H I column densities. The H I column density sensitivity (3σ over 16 km s−1) ranges from ∼5 × 1017 cm−2 at 90″ resolution to ∼4 × 1019 cm−2 at the highest resolution of 7″. The H I mass sensitivity (3σ over 50 km s−1) is ∼5.5 × 105 M⊙ at a distance of 10 Mpc (the median distance of the sample galaxies). The velocity resolution of the data is 1.4 km s−1. One of the main science goals of the survey is the detection of cold accreting gas in the outskirts of the sample galaxies. The sample was selected to cover a range in H I masses from 107 M⊙ to almost 1011 M⊙ in order to optimally sample possible accretion scenarios and environments. The distance to the sample galaxies ranges from 3 to 23 Mpc. In this paper, we present the sample selection, survey design, and observation and reduction procedures. We compared the integrated H I fluxes based on the MeerKAT data with those derived from single-dish measurement and find good agreement, indicating that our MeerKAT observations are recovering all flux. We present H I moment maps of the entire sample based on the first ten percent of the survey data, and find that a comparison of the zeroth- and second-moment values shows a clear separation in the physical properties of the H I between areas with star formation and areas without related to the formation of a cold neutral medium. Finally, we give an overview of the H I-detected companion and satellite galaxies in the 30 fields, five of which have not previously been cataloged. We find a clear relation between the number of companion galaxies and the mass of the main target galaxy
Tailored functional monolayers made from mesoionic carbenes
No full textInternational audienceSignificant progress has been made over the last decades in surface functionalization of coinage metals using thiols and more recently N-heterocyclic carbenes. As shown in this work, mesoionic carbenes (MICs) provide straightforward access to a novel class of surface ligands including electroactive ones and thus materials. Importantly, MICs are easily accessed from triazolium salts (TS) onto which functional groups may be attached with little synthetic effort. Here, we present a library of TS that were further converted, in situ, into MICs and grafted onto gold surfaces. The modified surfaces were thoroughly characterized by advanced spectroscopic methods such as XPS, infrared and Tip-Enhanced Raman Spectroscopy. Through cyclic voltammetry at 100 Vs-1, we could evaluate the surfacic concentration of the grafted molecules for electroactive MICs. We also prepared mixed MIC/thiol self-assembled monolayers, which opens the route to multifunctional surfaces
Possible origins of anomalous H I gas around MHONGOOSE galaxy, NGC 5068
No full textInternational audienceThe existing reservoirs of neutral atomic hydrogen gas (H I) in galaxies are insufficient to have maintained the observed levels of star formation without some kind of replenishment. This refuelling of the H I reservoirs is likely to occur at column densities an order of magnitude lower than previous observational limits (NH I, limit ∼ 1019 cm−2 at a 30″ resolution over a linewidth of 20 km s−1). In this paper, we present recent deep H I observations of NGC 5068, a nearby isolated star-forming galaxy observed by MeerKAT as part of the MHONGOOSE survey. With these new data, we were able to detect low column density H I around NGC 5068 with a 3σ detection limit of NH I = 6.4 × 1017 cm−2 at a 90″ resolution over a 20 km s−1 linewidth. The high sensitivity and resolution of the MeerKAT data reveal a complex morphology of the H I in this galaxy - a regularly rotating inner disk coincident with the main star-forming disk of the galaxy, a warped outer disk of low column density gas (NH I < 9 × 1019 cm−2), in addition to clumps of gas on the north-western side of the galaxy. We employed a simple two disk model that described the inner and outer disks, which enabled us to identify anomalous gas that deviates from the rotation of the main galaxy. The morphology and the kinematics of the anomalous gas suggest a possible extra-galactic origin. We explore a number of possible origin scenarios that may explain the anomalous gas, and conclude that fresh accretion is the most likely scenario. The reduced datacubes as FITS files are available at https://mhongoose.astron.nl
UPPER INDUS EPIGRAPHIC AND PETROGLYPHIC COMPLEXES IN NORTHERNPAKISTAN: DIGITAL SURVEY PROGRESS REPORT (2022–2024) AND NEW TOOLSFOR ANALYSIS OF INSCRIPTIONS AND PETROGLYPHS
No full textInternational audienceSince the previous presentation at the 25th EASAA meeting in Barcelona, a project team ofdigital imaging specialists based in the Lahore University of Management Sciences (LUMS)has made considerable progress in collecting and processing data from sites in the flood zonesof Diamer-Basha dam under construction on the Upper Indus River in Chilas-Diamer district,Gilgit-Baltistan, Pakistan. This work builds upon and enhances previous European and SouthAsian research published to date in volumes of Antiquities of Northern Pakistan, detailedcatalogs of selected sites in Materialien zur Archäologie der Nordgebiete Pakistans, and anonline database of the Heidelberger Akademie der Wissenschaften. In addition to Hodar andThalpan sites on the Indus right bank, surveys of Chilas sites (Chilas Bridge, Chilas 7–15),Oshibat, Turril Nala, Thor sites, and Minar Gah on the Indus left bank have been completed,with the aim of generating comprehensive 3D models of individual rocks usingphotogrammetry 2000+ models posted to Sketchfab collections), panotours for virtual tours,and point clouds from terrestrial laser scanning from which various digital assets can begenerated (examples are available at http://heritage360.pk/Diamer/Diamer.html). In tandem with providing a progress report on field survey activities, this presentation will alsoaim to introduce tools for analysis of the written and visual materials developed throughinternational collaboration with European, Australian, and Canadian researchers andinstitutions. A repository of images hosted on HeidICON (Heidelberg University Library)enables IIIF tagging. A controlled vocabulary with interoperable terms specifically relevant foranalysis of Upper Indus petroglyphs and inscriptions developed by Ani Danielyan and JasonNeelis is posted to Research Vocabularies Australia. An Image Annotation Workbench (part ofREAD Workbench) allows researchers to apply the terms to 2D images, which can also belinked to the 3D photogrammetry models. By sharing these new tools with archaeologists andart historians, we seek further input on methodological approaches that may be usefully appliednot only to the research field of Upper Indus inscriptions and petroglyphs in northern Pakistan,but to other fields as well. Our goal is to stimulate productive discussions about the scope forusing these tools for analysing valuable epigraphical and visual data that is under imminentthreat
Five years on: analysis of university lecturers’ experiences of the French government’s health promotion education program
No full textInternational audienceAbstract Background The National Health Promotion Intervention Program by Student (HPIPS) is a French government educational program introduced in 2018, aiming at developing all health students’ health promotion knowledge and abilities, as well as implementing health promotion interventions for specific subpopulations in the general public. Its pedagogical framework was elaborated in 2018 and then evaluated by the French Council for Public Health in 2022, highlighting certain difficulties for the program to be homogeneously implemented in France. The aim of this study was to explore and describe the experiences and feedback of university lecturers in charge of this HPIPS training. Methods Semi-structured interviews were conducted with HPIPS lecturers from various health fields and from French universities, and a qualitative content analysis was carried out. Results Fourteen interviews were conducted during the autumn of 2022 with HPIPS program university lecturers including five doctors, three dentists, two nurses, two pharmacists, one midwife, and one physiotherapist from eight different towns belonging to six regions. Depending on the professional background, the component, and the local resources available, the teaching experience varied from one lecturer to another. A number of difficulties arose in setting up this educational program and complying with the latter legislation. The work overload was considerable, and the lecturers’ heavy commitments some lecturers to be discouraged, especially since some lecturers were not trained in health promotion abilities. Although interprofessionality was a strength of this HPIPS, it was also its main challenge. Pedagogical innovations were developed, notably through the use of digital technology; cross-disciplinary collaboration was established; and lecturers–students specific boundaries have emerged thanks to this health promotion project. Conclusions In France, setting up the HPIPS rapidly was experienced as a real pedagogical challenge for the interviewed university lecturers. While most of them noted the positive and beneficial contributions made by the introduction of prevention and health promotion intervention skills for health students, they also shared recommendations in order to match the ambitions and increase the HPIPS impact on the development of a culture of prevention and health promotion among health students
“Codex Renatus Lincopensis” and two other Tibetan and Mongolian folios preserved in the Linköping City Library
No full textInternational audienceThe paper presents one Tibetan and two Mongolian folios that have been held at the Linköping City Library, most probably since the 1720s. One of these folios is closely associated with the famous Swedish writer August Strindberg, who somewhat misleadingly referred to it as ‘Codex Renatus Linkopensis’. An intriguing Russian inscription found on this folio, dated July 1720, is given close attention, revealing that the folio could not have been brought to Sweden by Johan Renat, a captive Carolean who spent many years at the court of the Dzungar rulers. The authors suggest Johan von Strahlenberg as a more plausible source of the folios
Коллекция вещей римского времени и эпохи Великого переселения народов из Восточного Крыма
No full textInternational audienceThe article examines a collection of metal elements of costume from the Roman period and the Great Migration periodfrom the State Historical Museum. It comes from Eastern Crimea (Kerch or Theodosia). Among the Roman time artifacts,the most numerous are brooches and buckles, bracelets, and pendants of “barbarian” origin, associated with the Sarmatians,Germans, and, possibly, the Western Balts. Items from the era of the Great Migrations, including brooches, buckles, andbracelets, belong to the Goths of the Cimmerian Bosporus. Their presence in this collection allows us to reiterate the questionabout the population of Theodosia at the beginning of the Middle Ages.В статье рассматривается коллекция металлических элементов костюма римского времени и эпохи Великого пере-селения народов из Государственного Исторического музея. Она происходит из Восточного Крыма (Керчь или Феодо-сия). Среди предметов римского времени наиболее многочисленными являются фибулы и пряжки, браслеты и подвески«варварского» происхождения, связанные с сарматами, германцами и, возможно, западными балтами. Вещи эпохиВеликого переселения народов, фибулы, пряжки и браслеты принадлежат готам Боспора Киммерийского. Их наличиев данной коллекции позволяет снова поставить вопрос о населении Феодосии в начале средневековья
