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Flexible Determination of the Nonlinear Refractive Index or Pulse Duration in the Visible Range Using Z-Scan-Based Technique: Application to Fused Silica
No full textSediment implication in shift in nutrient limitation and impact on purification capacity: Application on a common Atlantic east coast pond
No full textInternational audienceSalt marshes are widely recognized as regulation areas of nutrient flows to the ocean. However, poor knowledge of nutrient dynamics in these environments counteracts the understanding of nutrient regulation within the land- sea continuum, previous works mainly focusing on the water compartment. To overcome this gap, an experimental pond was monthly (open system) and weekly (closed system) monitored between February and October 2021. Bio(geo)chemical parameters (in water and sediment) and nutrient fluxes at the sediment-water interface (SWI) were relevantly explored to highlight the coupling between the benthic and pelagic compartments. A significant shift from P limitation (February–June period) to N limitation (July–October period) was observed and attributed to the phosphate mobilization (named soluble reactive phosphorus, SRP) processes in the sediment and its effluxes toward the water column. This SRP mobilization was strongly linked to the respiration of iron oxides for mineralization of organic matter (OM) and anammox processes. Surprising high carbon production in September (>1200 mgC. m-3. d-1 ) in a low nutrient concentration range indicated significant regenerated N production and potentially new P production. Monitoring in enclosed system indicated a 3-week water retention time for a maximum nutrient removal and minimal impact for water export to the coastal waters. In non-bloom period, sediment SRP efflux from the sediment could contribute up to 40 % of SRP increase in the water column in September and to 60 % of the P-production demand in October. This work highlighted the importance of sediment for water nutrient re-supply and the temporality of water retention time in pond system to optimize purification effect and limit risks of eutrophication in coastal waters. While the eutrophication potential associated with nitrogen seemed to be reduced in such pond, that of phosphorus needs to be more considered
DISCRETE HARMONIC POLYNOMIALS IN MULTIDIMENSIONAL ORTHANTS
No full textWe consider multidimensional random walks in pyramidal cones (or multidimensional orthants), which are intersections of a finite number of half-spaces. We explore the connection between the existence of (positive) discrete harmonic polynomials for the random walks, with Dirichlet conditions on the boundary of the cone, and geometric properties of the cone, being or not the Weyl chamber of a finite Coxeter group. We prove that the first property implies the second, derive the converse in dimension two and show in this case that it coincides with the probabilistic harmonic function.</div
Determinants of retinopathy and short-term neurological outcomes after cerebral malaria
No full textInternational audienceAbstract Neurological abnormalities are frequent after cerebral malaria (CM) resolves. The identification of survivors that should be prioritized during follow-up after CM is necessary for post-hospitalization care. We analysed social, clinical, and immune determinants of malarial retinopathy (MR) and short-term neurological outcomes after CM. Children aged 24 to 71 months with CM were prospectively followed-up until 28 days after admission at two hospitals in Benin. Direct ophthalmoscopy was performed shortly after admission. Plasma biomarkers were measured at admission. A neurocognitive deficit screener was administered at discharge and 21–28 days after admission. Of 70 children, 20 died before discharge (28.6%). Neurological deficits decreased from 100% on admission to 48.9% at discharge, and to 16.7% at 21–28 days after admission. MR was found in 58% of children. In multivariate analysis, factors associated with MR were a traditional consultation before admission and study site. In addition, neurological deficits were associated with MR (Odds Ratio 5.54 95% CI (1.30–23.54)). In univariate analysis, higher plasma levels of angiopoietin-2 were associated with neurological deficit at discharge and at days 21–28 post-admission. Therefore, MR and endothelium activation may be markers of neurological deficit, the former at hospital discharge and the latter at discharge and at D21–D28 post-admission
Psychometric properties of the Feeling of Unsafety Scale—Arabic in general population adults
No full textInternational audienceBackground Feelings of unsafety, including fear of crime, uncertainty, or insecurity, can negatively impact individuals by reducing psychological well-being and worsening health. Validating a simple and cost-effective tool to assess the general feeling of unsafety in the Arabic-speaking population, primarily residing in the Middle-East and North-Africa (MENA) region where safety can be a major concern, would be highly beneficial. The study aimed to translate the Feeling of Unsafety Scale into Arabic (FUSA) and evaluate its psychometric properties, including internal reliability, sex invariance, composite reliability, and correlation with a measure of intolerance of uncertainty. Methods A total of 484 Arabic-speaking adults was recruited between March and April 2024. A self-administered anonymous survey was distributed through social media using a Google Forms link. We used the FACTOR software to conduct the exploratory factor analysis (EFA) of the FUSA scale and RStudio for the confirmatory factor analysis (CFA). Results The confirmatory factor analysis of the unidimensional model was poor; the EFA conducted on the first split subsample showed a two-factor solution, with the CFA conducted on the second split subsample showing good fit. The latter model fit indices improved even more after adding a correlation between items 2–5 due to high modification indices. The reliability of the scale was excellent as shown by the McDonald’s omega and Cronbach’s alpha values for the total score ( ω = 0.89 and α = 0.90), Factor 1 = Feeling of outdoor unsafety (ω = 0.91 and α = 0.91) and Factor 2 = Feeling of indoor unsafety (ω = 0.83 and α = 0.83). Invariance was established between males and females. Good concurrent validity was attested by positive correlations between FUSA scores and intolerance of uncertainty dimensions. Conclusion The FUSA was found to be reliable, valid, and cost-effective for measuring the general feeling of unsafety in the general population. To evaluate its practical effectiveness and further enhance data on its construct validity, future studies should assess the scale in diverse contexts and among specific populations
VOC-ADO: A lexical database for French-speaking adolescents
No full textInternational audienceWe present VOC-ADO, a database of the written vocabulary of French adolescents between the ages of 11 and 15 (French secondary school students). VOC-ADO provides a wealth of lexical information for 110,338 words listed in school textbooks of all disciplines (i.e., academic vocabulary), as well as novels, comics, and magazines (i.e., non-academic vocabulary). For each word, several indexes of frequency and lexical dispersion are reported, as well as word length, syntactic categories, orthographic neighborhood size, and lemma frequency. Each analysis is presented separately for the Academic and Non-academic subcorpora, as well as for the overall Global corpus. Analyses of the corpora indicate that the Academic subcorpus contains a smaller variety of unique words than the Non-academic subcorpus and exhibits higher lexical sophistication. By contrast, there is a larger proportion of content words in non-academic media than in school textbooks. Finally, VOC-ADO shows a strong frequency correlation with Manulex, a French database of elementary school vocabulary, and Lexique, a lexical database of adult vocabulary. However, many words present in VOC-ADO are not found in elementary school vocabulary. These results underscore the need to examine lexical development beyond elementary school, considering the unique characteristics of the written vocabulary encountered by French-speaking adolescents. In this regard, VOC-ADO provides researchers, educators, and clinicians interested in adolescent literacy with a valuable tool to select and analyze words based on specific characteristics. The database is freely available and can be downloaded by clicking on the following link: VOC-ADO Database link
Acne-induced Post-inflammatory Hyperpigmentation: From Grading to Treatment
No full textInternational audienceAcne-induced post-inflammatory hyperpigmentation (AI-PIH) can occur without any visible clinical evidence of significant inflammation, even in patients with mild to moderate acne. Currently, visual assessment is the main criterion for evaluating the severity of PIH, including that of AI-PIH in daily clinical practice. Treatment indications are lacking. This work provides an easy-to-use AI-PIH severity grading tool for daily clinical practice as well as indications on how to prevent and treat AI-PIH using currently available treatment options. Five experts in acne provided a short overview concerning the epidemiology and physiopathology of AI-PIH, developed an AI-PIH severity grading tool, and proposed preventive measures as well as an AI-PIH treatment algorithm. Only a small number of epidemiological data on AI-PIH are available, confirming that the condition is mainly observed in patients with Phototypes IV to VI. The physiopathology of AI-PIH is still not completely understood. Innate immunity, Cutibacterium acnes, and external factors such as UV radiation, visible light, and air pollution play a role in its development. An easy-to-use AI-PIH severity grading tool (Acne PIgmentation Grading) allows quick assessment of acne severity during the consultation, and, in addition to proposed preventive measures, a treatment algorithm is proposed according to AI-PH severity. Patient education remains key. Providing an AI-PIH severity assessment tool as well as preventive and treatment recommendations may help to manage AI-PIH more efficiently
Jeunes chercheur.es d'ESO-Caen : quels héritages ?
No full textLongtemps homogène du point de vue des trajectoires universitaires, la composition du bureau des jeunes chercheur.e.s du laboratoire (203/204 dans la MRSH) s'est récemment vu transformée. Actuellement, la majorité des doctorant.e.s n'a pas suivi le master adossé au laboratoire Espaces et Sociétés (ARTESO puis GAED) et a fortiori n'est pas diplômée de l'UFR SEGGAT. Dès lors, plusieurs questions surviennent : Quels sont nos liens ? Avons nous un héritage en commun ? Si oui, lequel ? Quels éléments expliquent nos différences d'approches scientifiques ? Cet arbre (généalogique) a été réalisé à partir des thèses en cours ou soutenues récemment (entre 2019 et 2024)
