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L’ expression émotionnelle en fonction du matériel dans la production d’un dessin expressif
No full textBetween the ages of 3 and 5, children gradually develop the ability to identify, understand, and express emotions. Drawing, as a non-verbal form of expression accessible from an early age, provides a valuable medium for observing these emotional skills. This study focuses on how children express the emotions of joy and anger through an expressive human figure drawing, depending on their age and the art materials made available to them. Using both quantitative (frequency of tool usage) and qualitative (types of emotional indicators used) analyses, the research explores the impact of the emotional valence of materials (neutral, positive, negative) on children’s graphic choices. The results reveal a developmental progression in how children select materials and symbolise emotions: younger children favour simple tools and literal indicators, while older children employ more varied and symbolic strategies. This work highlights the expressive potential of materials in children's drawings and underlines its relevance in supporting emotional education in early childhood education.Entre 3 et 5 ans, les enfants développent progressivement leur capacité à identifier, comprendre et exprimer les émotions. Le dessin, langage non verbal accessible dès le plus jeune âge, constitue un support privilégié pour observer ces compétences. Cette recherche s’intéresse à la manière dont les enfants expriment émotionnellement la joie et la colère à travers un dessin expressif de bonhomme, en fonction de leur âge et du matériel plastique mis à leur disposition. En s’appuyant sur une analyse à la fois quantitative (fréquence d’utilisation des outils) et qualitative (type d’indices émotionnels mobilisés), l’étude explore l’impact de la valence émotionnelle du matériel (neutre, positive, négative) sur les choix graphiques réalisés. Les résultats montrent une évolution développementale dans la sélection des matériaux et dans la symbolisation des émotions : les plus jeunes privilégient des outils simples et des indices littéraux, tandis que les plus âgés mobilisent des procédés plus symboliques et variés. Ce travail met ainsi en lumière le rôle expressif de la matière dans le dessin et son intérêt pour accompagner l’éducation émotionnelle dès la maternelle
Filament formation and NAD processing by noncanonical human FAM118 sirtuins
No full textInternational audienceSirtuins are an ancient family of enzymes with diverse nicotinamide adenine dinucleotide (NAD)-dependent activities. Here we identify family with sequence similarity 118 member B (FAM118B) and FAM118A—two understudied vertebrate proteins—as vertebrate-specific sirtuins with similarities to bacterial antiphage sirtuins. We show that human FAM118B forms head-to-tail filaments both in vitro and in living human cells, a feature that appears to be conserved in both FAM118B and its paralog FAM118A across vertebrates. While human FAM118B and FAM118A have individually very weak NAD-processing activity in vitro, their interaction leads to markedly increased activity, suggesting a tightly regulated system. The overexpression of wild-type human FAM118B and FAM118A leads to strongly decreased NAD levels in human cells, an effect that is abolished in catalytically dead or filament-deficient mutants. Our study highlights filament formation and NAD processing as conserved mechanisms among immunity-associated sirtuins across evolution
Pulsar B1237 + 25 aberration/retardation analysis from decimetre to decametre wavelength: challenge to ‘radius-to-frequency mapping’
No full textInternational audiencePSR B1237 + 25 is perhaps the canonical example of a pulsar with a core/double cone profile. Moreover, it is bright with little spectral turnover, and its profile perhaps uniquely remains undistorted by scattering far into the decametric band. Here, we assemble more than a dozen of the highest quality profiles (30 MHz to 5 GHz) from half a dozen observatories, where possible polarimetric. The pulsar's 2.6 • core component marks the magnetic axis longitude, and we confirm that this point coincides both with the linear polarization angle inflection point and the zero-crossing of its antisymmetric circular signature -thus providing the possibility to estimate emission heights over a very broad band using aberration/retardation (A/R). We then carefully fit the profile components with Gaussians to identify and study the subtle asymmetries produced by A/R. We find a consistent A/R in the pulsar's profiles of some 0.5 • longitude or 2 ms -corresponding to a putative conal emission height of 200-400 km -with a formal error of about 100 km. Our analysis finds no evidence whatsoever for an emission height increase with wavelength, the so-called radius-to-frequency mapping. Nor do we find any significant difference in A/R effect between the outer and inner cones.</div
A narrative review of potential therapies for the treatment of myocardial tissue in relation to heart failure
No full textInternational audienceHeart failure (HF) is not a disease but a combination of signs and symptomscaused by the failure of the heart to pump blood to support the circulatory system atrest or during activity. HF is the potential end stage of all heart diseases in whichcardiomyopathies are a diverse group of cardiac disorders with distinct phenotypes,depending on the protein and pathways affected. Cardiomyopathies representmajor causes of morbidity and mortality at all ages in humans in which hypertrophiccardiomyopathy (HCM) and dilated cardiomyopathy (DCM), are the most common.Among the different common diagnostic tests for heart failure such as physicalexamination, blood tests, chest X-rays, electrocardiogram (ECG), etc. ultrasound hasalso been used not only for diagnosis such as echocardiography but also fortherapeutic purposes. The development of therapeutic strategies for HF aiming toimprove the heart’s function, delay progression of HF, and treat HF symptoms aswell as to stimulate the capacity to regenerate cardiomyocytes via stem cell therapyhave been under intensive research interest. This narrative review aims to presentthe current understanding of the pathogenesis, diagnosis, and treatment of HF.Furthermore, as a perspective, this review navigates emerging therapies for HF byemphasizing on the use of low-intensity pulsed ultrasound (LIPUS) as a noninvasivetherapy for (1) stimulation of the myocardial tissue reconstructionmechanisms; and (2) exploration of the molecular mechanisms behind themechanotransduction from the muscle LIM protein (MLP), which is believed to beinvolved in human HF, using its expression vector via glycosylphosphatidylinositol,GPI, anchor
Ireland in the Concert of Nations
No full textInternational audienceThis volume explores different aspects of Ireland, its history and cultural as well as artistic expressions, around the theme of the concert of nations, since independence and the partition of the country back in 1922. The angle chosen is at once historical, political and aesthetic. The two parts of the book – the political and the artistic – reflect the multidisciplinary approach of Irish studies in France, and the desire to give substance to this theme well beyond the most obvious question of international relations between states.The book follows in the footsteps of the Decade of Commemorations that marked the centenary of the events ranging from 1912 to 1923 in Ireland. It bears witness to the abundant historiographical and creative activity of the early twenty-first century. It examines the increasingly complex issues and imaginaries of migration and diaspora, on a planet that seems to be shrinking, reminiscent of the “global village” described by Marshall McLuhan as early as 1967, where socio-economic, political and environmental questions and crises arise and collide more dramatically than ever
A HyperFlash and ECLAT view of the local environment and energetics of the repeating FRB 20240619D
No full textInternational audienceTime-variable propagation effects provide a window into the local plasma environments of repeating fast radio burst (FRB) sources. Here we report high-cadence observations of FRB 20240619D, as part of the HyperFlash and ÉCLAT programs. We observed for h and detected bursts, including bursts with high fluence ( Jy ms) and implied energy. We track burst-to-burst variations in dispersion measure (DM) and rotation measure (RM), from which we constrain the parallel magnetic field strength in the source's local environment: mG. Apparent DM variations between sub-bursts in a single bright event are interpreted as coming from plasma lensing or variable emission height. We also identify two distinct scintillation screens along the line of sight, one associated with the Milky Way and the other likely located in the FRB's host galaxy or local environment. Together, these (time-variable) propagation effects reveal that FRB 20240619D is embedded in a dense, turbulent and highly magnetised plasma. The source's environment is more dynamic than that measured for many other (repeating) FRB sources, but less extreme compared to several repeaters that are associated with a compact, persistent radio source. FRB 20240619D's cumulative burst fluence distribution shows a power-law break, with a flat tail at high energies. Along with previous studies, this emphasises a common feature in the burst energy distribution of hyperactive repeaters. Using the break in the burst fluence distribution, we estimate a source redshift of -. We discuss FRB 20240619D's nature in the context of similar studies of other repeating FRBs
The impact of “empty-corner” tetrahedra in the synthesis of MFI type zeolites: unveiling selenium stereoactivity
No full textInternational audienceThis study investigates the impact of selenium in different oxidation states, specifically Se 6+ and Se 4+ , on the structural features of MFI-type zeolites. Se 4+ is characterized by trigonal pyramidal coordination, forming a [Se 4+ O 3 E] 2-entity (E being an active lone pair of electrons). The three-coordinated [Se 4+ O 3 E] 2- entity represents an "empty-corner tetrahedron", analogous to four-coordinated [Se 6+ O 4 ] 2-and [SiO 4 ] 4- tetrahedra. Aiming to understand the impact of lone pair bearing complexes on MFI, Se 4+ and Se 6+ were introduced through a one-pot synthesis approach giving rise to Se(IV)-MFI and Se(VI)-MFI samples. Both the Se(IV)-MFI and Se(VI)-MFI samples exhibit monoclinic symmetry at room temperature, transitioning into orthorhombic symmetry at temperatures above 100 °C and reverting to monoclinic symmetry upon cooling. A significant difference was observed in terms of the silanol content, i.e. Se(IV)-MFI shows a lower concentration of SiOH compared to Se(VI)-MFI. These observations are coherently supported by 29 Si and 77 Se NMR, Se K-edge XAS, FT-IR, and Raman spectroscopy, suggesting that Se 4+ oxycomplexes with a lone pair of electrons are more favorable for incorporation into the MFI framework compared to Se 6+ . 77 Se NMR analyses revealed similar Se tetrahedral coordination in both Se(VI)-MFI and Se(IV)-MFI, indicating the stabilizing role i.e. oxidation of Se 4+ to Se 6+ directly during crystallization of MFI. Considering the differences in the silanol content and the similarities in Se coordination states in Se(IV)-MFI and Se(VI)-MFI, the transformation of "empty-corner tetrahedra" into regular tetrahedra i.e. selenite to selenate favors the introduction of Se in the MFI framework. These results provide valuable insights into the tunability of zeolite frameworks using selenium in different oxidation states
Formation of skin-core structure in filled room-temperature vulcanized polydimethylsiloxane after long exposure to moderate temperatures
No full textInternational audienceThis study highlights the formation of a skin-core effect inside a filled silicone rubber exposed to air for durations up to 600 days at temperatures between 30 • C and 70 • C. Coupling mechanical and physico-chemical characterisations reveal that the volatile components, such as crosslinking by-products and oligomers, evaporate from the elastomeric network during the exposure, resulting in the shrinkage of the sample. This phenomenon gives rise to the formation of a composition gradient from the sample's surface towards its core. All the samples become more brittle with ageing, but the tensile modulus increase only slightly at the longest durations and highest temperatures. More fillers are found on the outer surface while the infrared spectra in the core of the sample remain unaffected by neither the temperature nor the duration. The nanoindentation highlights gradients of elastic modulus on the cross-section and provides an estimation of the skin thickness. By wrapping the samples in aluminum foil, the evaporation of volatile components is prevented. The measured properties remain constant with the duration of thermal exposure even at the highest temperature
Mn <sup>2+</sup> Complex of a Fluorinated CDTA‐Derivative: Stability, Inertness, and Paramagnetic <sup>1</sup> H, <sup>17</sup> O, and <sup>19</sup> F Relaxation Properties
No full textInternational audienceL2 is a bisamide derivative of cyclohexyl-diamine tetraacetate (CDTA) containing one trifluoromethyl-piperidine- and one dimethyl-amide. While the amide functions are stable at pH 7, at pH 4.35 hydrolysis occurs after 1 day, and it is faster for the amide involving the piperidine. pH potentiometry showed lower basicity for L2 than for CDTA, and similar stability for the two complexes (pMn = 8.28 vs. 8.68 for MnL2 and MnCDTA, respectively). The replacement of carboxylates by amides results in two orders of magnitude higher kinetic inertness for MnL2 (t1/2 = 1134 hours vs. 12 hours; pH 7.4). 17O NMR confirmed one inner sphere water in MnL2 and fast exchange (kex298 = 2.8 × 107 s−1). Its proton relaxivity is remarkable for a small Mn2+ chelate (r1 = 4.59 mM−1s−1, 25 °C, 20 MHz). In the complex, 19F relaxation is strongly accelerated with respect to free L2, with more important effect on longitudinal (130-fold), than on transverse relaxation (25–70-fold). A Mn─F distance of ∼8 Å was estimated from the 19F relaxation rates. MnL2 provides good signal-to-noise ratios on 19F phantom UTE MR images. These data show that fluorinated, monohydrated Mn2+ complexes can offer both 1H and 19F MRI detection
Development of optimized exatecan-based immunoconjugates with potent antitumor efficacy in HER2-positive breast cancer
No full textInternational audienceThe prognosis of human epidermal growth factor receptor 2 (HER2)-positive breast cancer has significantly improved with the advent of anti-HER2 therapies, especially antibody-drug conjugates (ADCs). In this field, ADCs, like trastuzumab deruxtecan (T-DXd), using camptothecin analogs, represent a promising strategy. However, T-DXd can induce resistance and serious adverse effects, potentially driven by a nonspecific Fcγ receptor-mediated endocytosis. Here, we report the development of novel HER2-targeting conjugates, using the camptothecin derivative exatecan and a linker optimized to control hydrophobicity. Three formats were evaluated: a high drug-toantibody ratio (DAR) 8 IgG-based ADC (IgG(8)-EXA), and two DAR 4 Fc-free constructs (Mb(4)-EXA and Db(4)-EXA). Thus, IgG(8)-EXA and Mb(4)-EXA displayed potent, specific cytotoxicity against HER2-positive breast cancer cells and strong antitumor activity in vivo. Notably, IgG(8)-EXA exhibited a favorable pharmacokinetic profile, despite its high DAR, supporting the potential of this drug-linker design. These two conjugates represent promising candidates for further preclinical developmen