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Quantification of matrix effects observed in LIBS analysis of metal alloys
No full textInternational audienceAs a direct solid analysis technique combining sampling and excitation of the material by laser ablation, LIBS is subject to matrix effects. These effects result in variations in ablated mass, temperature, and plasma density from one material to another. They are therefore essential to characterize when dealing with different types of matrices. Certain quantification methods, such as the well-known CF-LIBS, allow them to be corrected based on spectroscopic measurements of plasma characteristics [1]. However, these measurements are subject to uncertainties related to spectroscopic parameters such as the Stark broadening parameter or the Einstein coefficient of the transition, and/or measurement biases due, for example, to self-absorption.Here, we are interested in accurately characterizing the matrix effects observed in a model case, namely the analysis of impurities in metal alloys. To do this, we use a method described in previous work, in which a tracer element is deposited on the surface of the samples [2]. Iron is chosen because it allows the temperature and electron density of the plasma to be measured. The deposit is made in such a way that it has only a marginal, or even negligible, influence on ablation and plasma parameters. The ablated mass is then measured by an interferometric profilometer. The temperature is determined by a Boltzmann plot, with particular attention paid to the choice of lines limiting measurement bias. Finally, the electron density is estimated in the conventional manner by measuring the Stark broadening.We will discuss the measurements of these three parameters characterizing matrix effects, and we will present calibrations of iron concentration in seven metal alloys, corrected for variations in ablated mass, plasma temperature, and density. The results show that matrix effects can be satisfactorily corrected for four of them. The discrepancies observed for the others will also be discussed. Differences in crystal structure and vaporization yield of the ablated material may be invoked to explain these discrepancies
Plasticity in the brooding cidaroid Ctenocidaris nutrix : a morphological, trophic, and molecular investigation
No full textInternational audiencePhenotypic plasticity refers to the capacity of an organism’s phenotype to vary in response to changes in environmental conditions, without any change in the individual genotype. Sea urchins (Echinoidea) are well-known for their morphological and behavioural plasticity in response to changing habitats or trophic environments. Phenotypic plasticity has been little studied in directly developing species, in which low levels of phenotypic plasticity are usually expected as a consequence of high levels of genetic differentiation among populations and local genetic adaptation. In the present work, we report a significant plasticity in the direct-developing and brooding sub-Antarctic species Ctenocidaris ( Eurocidaris ) nutrix (Echinoidea, Cidaridae) through morphological and trophic analyses of gut contents and δ 13 C and δ 15 N isotopic compositions. Molecular data (COI mtDNA) confirm that the different phenotypes of C. nutrix , the short-spined C. nutrix nutrix and the long-spined C. nutrix longispina , are a single species restricted to sub-Antarctic waters. As formerly demonstrated in broadcasting echinoid species, morphological plasticity appears to be mainly linked to depth and swell exposure, specimens from exposed and shallow sites showing shorter spines and larger apical systems compared to specimens from sheltered or deep sites. Significant differences in the diet and trophic niche of the different phenotypes suggest that prey type and food diversity may also be a factor promoting distinct phenotypic responses, both in the feeding behaviour and morphology of echinoids
Randomized, multicenter Phase III trial of adjuvant chemotherapy with modified FOLFIRINOX versus capecitabine or gemcitabine in patients with resected ampullary adenocarcinoma
No full textInternational audienceBackground: Ampullary adenocarcinoma (AAC) is a rare and aggressive cancer with a 5-year overall survival (OS) rate ranging from 30% to 67% after resection due to a high recurrence rate. Yet, adjuvant therapy's role is still debated. Recent French FFCD-AC cohort study highlighted that adjuvant therapy, can benefit intermediate and high-risk patients. Chemotherapy regimens, include gemcitabine and 5-fluorouracil (5FU) but practices are highly heterogenous due to the low level of evidence. Previous studies suggest that combination chemotherapy, such as mFOLFIRINOX, could offer improved outcomes.Design: PRODIGE 98 - AMPIRINOX trial (NCT06813976) is a multicenter, open-label, randomized phase 3 trial designed to compare the efficacy of adjuvant mFOLFIRINOX versus single-agent chemotherapy (capecitabine or gemcitabine) in patients with resected AAC. Primary outcome is disease free survival and secondary outcomes include overall survival (OS), safety and quality of life. Patients (ages 18-79) must have undergone macroscopically complete (R0/R1) resection of AAC, with exclusion of patients previously treated with chemotherapy, and pT1N0M0 tumors. Ancillary studies will focus on an in-depth molecular profiling of AAC to identify prognostic and predictive biomarkers. AMPIRINOX is currently recruiting and is expected to provide essential data on how to optimize treatment for AAC patients in the coming years
Tree water status behavior of two common European urban species using dendrometric measurements and remote sensing imagery.
No full textInternational audienceWith growing urban populations and rising heatwaves, urban trees are increasingly valued for their cooling benefits through transpiration and shading. However, water stress can limit transpiration, and the effects of urban environment and species-specific traits on tree water status remain understudied. This work investigates how meteorology, soil imperviousness and species influence tree water status behavior, and how vegetation indices derived from remote sensing relate to tree water status, at both seasonal and individual tree scales. Eleven mature Acer platanoides and Tilia x euchlora trees (two common European urban species) growing under varying soil imperviousness levels in a medium-sized French city were monitored. For summer 2023 and spring 2024, two dendrometric indicators of water status - maximum daily shrinkage (MDS) and tree water deficit (TWD) - were calculated, and vegetation index NDVI was extracted from SuperDove imagery. Results show that TWD, more than MDS, effectively assessed tree water status and was closely linked to vapor pressure deficit and relative humidity. Higher soil imperviousness increased water deficit in both seasons, particularly for trees in pits. Acer platanoides exhibited a more isohydric strategy than Tilia x euchlora. NDVI was strongly correlated with TWD in summer 2023 (R² = -0.43), and with MDS in spring 2024 (R² = 0.40). These findings underline the value of dendrometric measurements in urban environments for understanding tree water status, and highlight the potential of very high spatio-temporal resolution satellite data to assess individual tree water status across cities, supporting improved management to maximize the cooling benefits of urban trees
Neurological and psychiatric issues in 187 adults with early-treated PKU: The ECOPHEN study
No full textInternational audienceIntroduction: Phenylketonuria (PKU) is an autosomal recessive disorder caused by mutations in the PAH gene leading to phenylalanine hydroxylase deficiency. This results in the accumulation of phenylalanine (Phe) in blood and brain, causing neurological and psychiatric impairments if untreated. Newborn screening (NBS) introduced in the 1960s enables early PKU diagnosis, allowing prompt dietary or sapropterin treatment. The long-term outcomes in adults with early-treated PKU, however, may include subtle neurocognitive deficits alongside somatic neurological and psychiatric complications, which remain incompletely characterized. Patients and methods: The ECOPHEN study was a French 5-year multicenter prospective cohort assessing neuropsychiatric disorders in adults with early-treated PKU. Results: Here are presented the data at inclusion. The study recruited 187 patients who were classified by PKU severity-classic, mild, or mild persistent hyperphenylalaninemia-and diet adherence status. Neurological history revealed symptoms in 11.2 % of patients, exclusively in classic PKU, including tremor, migraines, and balance disorders, without significant differences between diet groups. Neurological examination abnormalities predominantly included abnormal deep tendon reflexes in classic PKU patients. Psychiatric issues affected 25.7 % of patients across severity groups, mainly depressive episodes and anxiety, with no clear influence of diet adherence. Discussion/conclusion: The present study highlights neurological complications persisting despite early treatment, particularly in classic PKU. Diet adherence and current plasma Phe levels did not correlate significantly with neurological or psychiatric outcomes, possibly due to suboptimal metabolic control. Limitations included the cross-sectional design, absence of control group, and retrospective data collection. Overall, adults with early-treated PKU show a generally favorable outcome but remain at risk for neuropsychiatric manifestations, supporting the need for lifelong follow-up including neurologic and psychiatric evaluation
Some PDE's and their rogue waves +
No full textWe give some of our results over the past few years about rogue waves. For the (NLS) and (KP) equations, we give different types of representations of the solutions, in terms of Fredholm determinants, Wronskians and degenerate determinants of order 2N . These solutions are called solutions of order N . In the case of the (NLS) equation, the solutions explicitly constructed, appear as deformations of the Peregrine breathers PN as the last one can be obtained when all parameters are equal to zero. At order N , these solutions are the product of a ratio of two polynomials of degree N (N +1) in x and t by an exponential depending on time t and depending on 2N -2 real parameters: they are called quasi rational solutions. For the (KPI) equation, we obtain explicitly solutions at order N depending on 2N -2 real parameters. We present different examples of rogue waves for the (LPD) and Hirota equations
Shape-Morphing Photo-Crosslinked Alginate Hydrogels via Digital Light Processing 4D Printing
No full textInternational audienceThe development of smart biomaterials capable of dynamic shape transformation is a key challenge in advancing 4D printing for biomedical applications. In particular, hydrogel systems must combine biocompatibility with precise control over volumetric changes to enable functionalities such as tissue scaffolds, responsive implants, or drug delivery devices. In this study, methacrylated alginate was prepared for 3D photo-crosslinked hydrogels using digital light processing (DLP). Hydrogels were fabricated with either uniform isotropic or heterogeneous anisotropic photo-crosslinking patterns. A secondary level of physical crosslinking was introduced through coordination of alginate guluronate blocks with Ca²⁺ ions, resulting in controlled hydrogel contraction. Volumetric changes, water uptake, and compression properties were first investigated on isotropic hydrogels with varying degrees of photo-crosslinking. Results showed that increasing the degree of photo-crosslinking restricted swelling in phosphate buffered saline (PBS) and contraction in calcium solution, due to reduced mesh sizes within the hydrogel network. Furthermore, anisotropic photo-crosslinking enabled spatially programmed volumetric deformations, allowing tailored shape morphing upon swelling or contraction. This effect was demonstrated in 3D-printed films with gradient crosslinking, which exhibited bidirectional bending when alternately exposed to PBS and CaCl₂ solution. More complex deformations were achieved in tubular structures and porous cubes by designing specific crosslinking gradients. Finally, cytocompatibility assays performed on fibroblast NIH 3T3 cells confirmed the non-cytotoxicity of the 4D-printed devices, highlighting their potential for biomedical applications.1.</div
Expectations about plant edibility in 6-month-old infants
No full textThis article is part of a Special Issue entitled: ‘Cognitive Development’ published in Evolution and Human Behavior.International audienceWatching what others put in their mouths is a powerful way to learn what to eat. Yet human diets and eating behaviors are complicated, and not everything that goes into another person's mouth is food: The fusilli is edible, but the fork is not. Therefore, some selectivity is necessary to guide social learning processes about food. Here we examined 6-month-old infants' expectations about what kinds of entities are likely to be edible using a violation-of-expectation setup in which infants viewed an actor eating from two different items. We hypothesized that infants may have selective edibility expectations about plants, and in particular fruits, that stem from humans' long evolutionary history of foraging wild plant foods and specialization in higher caloric density plant parts. In Experiment 1 (N = 40), we found that infants expect plants, relative to feature-matched artifacts, to be edible, replicating a previous finding [Wertz & Wynn, 2014a]. In Experiments 2 (N = 40) and 3 (N = 39), we examined, for the first time, whether selective expectations about plant edibility are tied to particular plant parts. Our results showed that infants do not differentially expect leaves to be edible, but our results for fruits were inconclusive. Taken together, these findings suggest that infants differentially expect plants to be edible and that these expectations appear to be strongest for whole plants
Les mitards d’Alphonse : Boudard ou l’argot en témoignage
No full textInternational audienceThe time served in prison by Alphonse Boudard enabled him to accumulate a huge amount of slang vocabulary, which is the original part of its work.The following writings are a valued evidence on penitentiary slang used in the first part of the 20th century. This study identifies how and why Boudard is a unique emissary and observer in this literature era, thanks to its work on slang used by him and others inmates