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Internal browning detection in red-flesh apple (<i>Malus</i> <i>domestica</i>) using image analysis and acoustic signal-based detection
No full textInternational audienceUncorrelating red-flesh color and internal browning is a breeding target in the selection of red-flesh elite apple cultivars, and accurate phenotyping methods are needed to study the genetic architecture associated with internal browning. Image analysis combined with machine learning and two-stage data acquisition enabled the detection of seven QTLs for brown-related traits on LG1, LG9, and LG10 in four interconnected red-flesh F1 families. A major QTL on LG10, which colocalized with a polyphenol oxidase (PPO), was linked to early internal browning susceptibility. However, internal browning is a temporal and spatial process that involves biochemical (PPO-mediated phenolic oxidation) and structural (cellular integrity) factors. Non-destructive and accurate methods are required to evaluate internal browning throughout fruit senescence. For this purpose, acoustic signal-based detection of internal browning in red-flesh apple was investigated in one red-flesh parent. Machine learning models showed good accuracy in discriminating 'brown' and 'non brown' signals. cGAN data augmentation outperformed model performances suggesting that extended datasets should lead to better accuracy in internal browning detection. This study shows that acoustic measurement could be a valuable non-destructive tool to discriminate between brown and non-brown apples with potential applications for phenomic selection and/or automatic apple sorting. Altogether, this study provides insights into internal browning physiology in red-flesh apple with future applications in red-flesh breeding
« "Parle et je te dirai qui tu es". Langues, assignations identitaires et catégorisations sociales : quelles questions vives actuelles en sociolinguistique ? », Ouverture, co-animation et synthèse de Panel international
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The effect of extreme temperatures on healthcare utilization during pregnancy: Findings from a nationally representative survey in India
No full textInternational audienceBackground: Extreme temperatures are increasing in frequency and severity, posing growing risks to maternal and child health through adverse pregnancy and birth outcomes. This challenge is especially pronounced in countries like India, that lack adequate protections against climate-related health risks. While socio-economic and accessibility barriers already limit healthcare utilization during pregnancy, climatic factors such as extreme temperatures can create additional obstacles to accessing these essential services, thereby influencing pregnancy and birth outcomes both directly and indirectly.Methods: We conducted a cross-sectional analysis using data from the National Family Health Survey (NFHS-5), a nationally representative survey for India. We examined recent healthcare utilization reported by women in their fifth month of pregnancy or later (N = 10,606). Temperature exposure was measured using daily Wet Bulb Globe Temperature (WBGT), Heat Index, and Dry Bulb Temperature (DBT) matched to respondents' geo-coded residential clusters. We calculated the number of days during the study period when temperature values exceeded or fell below extreme temperature thresholds. Generalized mixed-effects models with Inverse Propensity of Treatment Weighting (IPTW) examined associations between extreme temperature and no healthcare contact, with effect modification tested across socioeconomic variables.Findings: Extreme heat exposure significantly increased the likelihood of healthcare non-utilization among pregnant women, with the strongest associations observed for WBGT and Heat Index measures. Each additional day above the 90th percentile WBGT threshold increased odds of no healthcare contact by 11%, with similar patterns across the 85th and 95th percentiles. Heat Index showed consistent positive associations across all thresholds (8-11% increases), while DBT trends were positive but not statistically significant. For extreme cold exposure, temperature indicators showed some association with healthcare non-utilization, though results were not consistent across exposure definitions. We did not find evidence of effect modification across socioeconomic groups, with only a few isolated exposure definitions showing significant difference between subgroups
Residential Segregation and Lung Cancer Risk in African American Adults
No full textInternational audienceImportance: Although structural racism as manifested by residential segregation is a documented root cause of race-based disparities in lung cancer survival and care, its impact on lung cancer development remains underexplored.Objective: To examine the association between residential segregation and lung cancer incidence and to identify modifiable factors mediating this association.Design, setting, and participants: This cohort study used data from the Southern Community Cohort Study (SCCS), which enrolled African American and non-Hispanic White participants who had no cancer at enrollment. The SCCS recruited participants from community health centers and random sampling from 12 southeastern states. Follow-up occurred between March 2002 to December 2019. Analysis was performed from April 2022 to March 2025.Exposures: Residential segregation, measured by the isolation index using 2010 census block group data, was linked to participants' baseline address.Main outcomes and measures: Incident lung cancer cases were identified via state cancer registries and the National Death Index (December 31, 2016, to December 31, 2019, depending on the state). Parametric g-computation estimated cumulative lung cancer risk under hypothetical interventions reducing residential segregation. Mediation analyses utilized inverse propensity weighting and marginal structural models to assess potential mediating pathways.Results: The cohort comprised 71 634 participants (median [IQR] age, 50 [45-57] years; 42 032 [58.7%] female; 50 898 [71.1%] African American and 20 736 [28.9%] non-Hispanic White) enrolled between 2002 and 2009. All hypothetical scenarios of lowering the isolation index were associated with lower 17-year culminative incidence of lung cancer among African American individuals but not among non-Hispanic White individuals. Approximately 24.7% (95% CI, 17.1%-36.6%) of the association between residential segregation and lung cancer risk in African American participants was mediated by menthol smoking, 13.1% (95% CI, 3.2%-25.4%) by exposure to particulate matter with a diameter of 2.5 μm or less, 4.7% (95% CI, 1.3%-9.6%) by secondhand smoke exposure at home, and 4.6% (95% CI, 2.1%-7.7%) by education.Conclusions and relevance: In this cohort study of non-Hispanic White and African American individuals, lower residential segregation was significantly associated with decreased lung cancer risk for African American individuals but not their non-Hispanic White counterparts. Mediation analysis identified mentholated smoking use and air pollution exposure as 2 major pathways between residential segregation and lung cancer incidence among African American adults. These findings suggest that lung cancer development reduction efforts should include policies with targetable segregation metrics and initiatives that lower exposure to documented mediators
Entretien avec André et Chantal Brasilier. "Partir du Visible, pour s’envoler vers l’Infini !" : la décoration de la chapelle Saint-Blaise de Pompadour
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Cytokinin-induced bud outgrowth depends on sugar metabolism and signalling
No full textInternational audienceShoot branching is a key process of plant growth and development, finely controlled by cytokinin and sugars. However, cytokinin fails to induce bud outgrowth in the absence of sugar and so far nothing is known about its ability to antagonize auxin when sugar availability is limited. Here we demonstrate in rose that cytokinin requires sugars metabolism and signalling to promote bud outgrowth, to downregulate the expression of RhBRC1, a transcription factor that inhibits axillary bud growth, and to antagonise the inhibitory effect of auxin on bud outgrowth. Cytokinin regulation of bud sink strength was tightly associated to sugar metabolism, which was evidenced by the gene expression in sugar metabolism (e.g. glycolysis, the tricarboxylic acid and the oxidative phosphate pentose phosphate: OPPP), metabolomic approach and the quantification of total carbon and nitrogen in buds. Cytokinin supply is associated with a significant upregulation of OPPP and nitrogen accumulation. Meanwhile, sugar upregulated bud sensitivity to cytokinin, associating with a significant down-regulation of cytokinin signalling regulator RhARR1. These findings highlight the key role of sugars metabolism and signalling in the cytokinin-induced bud outgrowth and provide new insights into the importance of nutrient-hormone crosstalk in the regulation of shoot branching
Identification of Natural Hydrogen Seeps: Leveraging AI for Automated Classification of Sub‐Circular Depressions
No full textInternational audienceHydrogen has long been used as an energy vector, but the recent discovery of natural hydrogen (H 2 ) opens the door for its use as a direct energy source. Identifying H 2 seepages is therefore crucial to advance exploration. Although the scientific community does not yet fully understand the parameters controlling H 2 leaks from underground, sub‐circular depressions (SCDs) appear to be key indicators associated with these emissions. However, distinguishing SCDs from similar landforms remains a challenge. This study leverages open‐source multispectral and high‐resolution imagery to train a deep learning model (YOLOv8) for classifying rounded landforms and detecting H 2 ‐related structures (i.e., SCDs). The model achieved 90% accuracy with Google Maps© imagery, outperforming Sentinel‐2 multispectral data. Applied to a pre‐existing data set from Brazil, the model allowed a large‐scale screening, discarding 52% of the structures as non‐H 2 emitting ones and pinpointing high‐potential areas for field validation. Future enhancements, including, for example, higher‐resolution input data and morphometric analysis, would aim to reduce false positives and boost predictive accuracy. This approach significantly improves H 2 exploration efficiency, with global applicability including some region‐specific adjustments during post‐processing analyses
Impact des pratiques linguistiques scolaires et familiales sur le potentiel créatif d'enfants polynésiens scolarisés en classe de CP-CE2
No full textInternational audienceDrawing on international research demonstrating the benefits of bilingualism for children’s academic success (Wright et al., 2015), the Ministry of Education of French Polynesia has launched an active policy aimed at revitalizing indigenous languages (Païa, 2014). Since 2019, a bilingual education program offering equal instructional time in French and Polynesian languages (DELPPH) has been implemented in 18 schools across several archipelagos. While these programs show promising outcomes in terms of linguistic revitalization (for a review, see Nocus, 2022), their long-term impact on students’ creative abilities remains largely underexplored (Yemez & Dikilitaş, 2022). Yet, bilingualism is known to have multifaceted effects on children’s cognitive development (Bialystok, 2009), including creativity (Dijk et al., 2019), understood here as the capacity to generate original and appropriate ideas (Lubart et al., 2019). However, this relationship remains debated (Booton et al., 2021), partly because it is difficult to disentangle the cognitive effects of bilingualism from those of linguistic and cultural practices.In the Polynesian context, while French–Polynesian bilingualism represents a significant cultural asset, its potential influence on children’s creativity has not yet been systematically studied. The DELPPH program, promoting balanced acquisition of both languages, offers a unique opportunity to examine its effects on students’ creative abilities.This study seeks to address this gap by investigating the impact of both school-based and family-based bilingualism on the creative development of Polynesian children, while considering the specificities of their linguistic and cultural environment. The research focuses on the linguistic practices of approximately 430 Polynesian students followed over three years (from first to third grade), across three geographic regions (Society Islands, Marquesas Islands, and Austral Islands). First, we examine school-based linguistic practices through the implementation of the DELPPH program. We hypothesize that participation in this program fosters positive effects on students’ creative performance, as measured through graphic and verbal creativity tasks. Second, we propose that this relationship between DELPPH participation and creativity is moderated by family language practices (FLP), assessed via questionnaires completed by children and their parents.Here, we present the results from the first year of the study, based on data collected at the beginning (T0) and end (T1) of the school year, involving 232 second-grade (CE1) students and 185 first-grade (CP) students.These findings contribute to the ongoing discussion of individual and site-related variability, shedding light on the influence of local cultural specificities and the differentiated impact of school-based and family-based linguistic practices on distinct dimensions of creativity (verbal and figural).S'appuyant sur les conclusions de la recherche internationale concernant les bienfaits du bilinguisme sur la réussite scolaire des enfants (Wright et al., 2015), le Ministère de l’Éducation de la Polynésie française mène une politique active en faveur de la revitalisation de ses langues autochtones (Païa, 2014). Ainsi, depuis 2019, un dispositif d’enseignement en langue polynésienne à parité horaire (DELPPH) est dispensé dans 18 écoles réparties à travers les différents archipels. Bien que ce type de programme soit prometteur sur le plan linguistique (pour une revue voir Nocus, 2022), leur impact à long terme sur les compétences créatives des élèves est peu étudié (Yemez & Dikilitaş, 2022). Pourtant, le bilinguisme est reconnu pour avoir des effets variés sur le développement cognitif des enfants (Bialystok, 2009), notamment sur leur créativité (Dijk et al., 2019), i.e. la capacité à produire des idées originales et adaptées (Lubart et al., 2019). Cependant, ces résultats ne font pas consensus (Booton et al., 2021), notamment en raison de la difficulté à distinguer les effets des facteurs cognitifs de ceux des pratiques linguistiques et culturelles. En Polynésie française, bien que le bilinguisme français-langue polynésiennes soit une richesse culturelle, son impact sur la créativité des enfants reste inexploré. Le dispositif DELPPH, favorisant un apprentissage équilibré des deux langues, représente une opportunité unique d’étudier cette influence sur les compétences créatives des élèves. Ainsi, notre étude vise à combler cette lacune en examinant de manière approfondie l’impact du bilinguisme scolaire et familial sur le développement créatif d’élèves polynésiens, en tenant compte des particularités de leur environnement linguistique et culturel. Elle concerne les pratiques linguistiques scolaires et familiales d’environ 430 élèves polynésiens suivis sur 3 ans du CP au CE2, et provenant de 3 sites géographiques (îles Sociétés, îles Marquises, archipel des Australes). D’une part, nous étudions les pratiques linguistiques scolaires à travers la mise en œuvre du DELPPH. Nous supposons que ce dispositif exerce un effet positif sur les performances créatives des élèves, évaluées à l’aide d’épreuves graphiques et verbales. Par ailleurs, nous postulons que ce lien entre le DELPPH et la créativité est modéré par les PLF, dont l’influence est mesurée grâce à un questionnaire rempli par l’enfant et ses parents.Nous présentons les analyses des données collectées en début (T0) et en fin d’année (T1) de la première année d’étude auprès de 232 élèves de CE1 et 185 élèves de CP.Les résultats obtenus permettent d’ouvrir la discussion sur la variabilité interindividuelle et intersites, afin de comprendre l’influence des spécificités culturelles locales, ainsi que l’impact différencié des pratiques linguistiques scolaires et familiales sur les différentes dimensions de la créativité (verbale et figurée)
Logistics Places: An Urban Geography of Post‐Industrial Blue‐Collar Workers: An Urban Geography of Post-Industrial Blue-Collar Workers
No full textInternational audienceThe Covid-19 pandemic and the various lockdown and curfew episodes in 2020 and 2021 cast light on places, flows and workers that had largely remained in the shadow of post-Fordist transformations and neoliberal policies at work in metropolitan areas. Due to shortages, the challenges related to supplying daily consumer goods were widely covered in the media. This chapter proposes to decipher the logistics places of metropolitan areas according to a social geography approach. It analyzes the geography of warehouse workers, which is mainly deployed around the urbanization front of agglomerations. The chapter then looks at the work and places of the delivery drivers and platform workers, mainly articulated around historical centers. In this way, it shows how this geography of postindustrial blue-collar workers and the associated social mobilizations partly reshape the contemporary working-class centralities of 21st-century urban areas. Warehouses are major places of employment for blue-collar workers, whom they are concentrating in increasing numbers