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Clustering and visualisation of the GABRIEL network expertise in the field of infectious diseases
No full textInternational audienceIntroduction The Global Approach to Biology Research, Infectious diseases and Epidemics in Low-income countries (GABRIEL) network is an international scientific network of 21 centres coordinated by the Merieux Foundation (Lyon, France). Mapping and characterising the similarities and differences in expertise and activities across four major infectious diseases (tuberculosis, antimicrobial-resistant infections, acute respiratory infections and emerging pathogens) among these centres would help to provide a better understanding of the network’s capacity. It will also highlight how the applied methodology can enhance information sharing within research networks. Methods Each centre responded to a questionnaire on their core activities and research themes. An advanced multivariate analysis was performed to relate all items together and highlight new synergies among members of the GABRIEL network. Similarities were found using a clustering algorithm and data were visualised using alluvial plots. Results This strategy enabled to find new patterns in the GABRIEL network for the implementation of new projects on global health, regardless of geographical proximity or historical connections. Five clusters based on core activities, consisting of 6, 1, 3, 9 and 2 research units, respectively, have been identified, with clusters 1 and 4, including the majority of the units. Four clusters have been defined based on the four major infectious diseases, comprising 7, 3, 5 and 6 research units, respectively. Conclusions The same methodology could also be applied to identify proximities on other networks of experts or between members of different networks for more efficient research or surveillance global programmes
High-Throughput Analysis of the Flagella FliK-Dependent Surfaceome and Secretome in Bacillus thuringiensis
No full textInternational audienceBacterial pathogens employ multiple strategies to invade and damage host tissues while evading immune defenses. Recent studies highlight flagella as crucial contributors to bacterial virulence, not only by facilitating motility, but also by regulating the secretion of virulence factors. However, the role of the flagella-dependent secretome remains largely unexplored. We have recently shown that FliK, a key regulator that defines substrate specificity in the flagellar export apparatus, is essential for the resistance of Bacillus thuringiensis (B. thuringiensis) against antimicrobial peptides (AMPs) and its virulence in a Drosophila infection model. In this study, we used liquid chromatography-tandem mass spectrometry to conduct a large-scale comparative analysis of the proteins secreted in culture supernatant or associated with the cell wall of the ΔfliK mutant and its reference strain. Our results reveal significant differences in the secretome and surfaceome of the ΔfliK mutant compared to the reference strain. These findings emphasize the role of FliK in regulating the production and secretion of several proteins, underscoring the importance of flagella in controlling various biological processes. This work provides valuable insights into the functional characterization of potential candidate proteins involved in B. thuringiensis virulence and AMP resistance mechanisms. Overall, these results open new perspectives for understanding the molecular processes that govern bacterial resistance to AMPs
Sociodemographic impact on smart cities IoT adoption in China
No full textInternational audienceDigital disruption is one of the most important social megatrends that deeply impact recent and future economic activities. IoT has contributed to the development of Chinese smart cities in recent years. Building on the authors' prior study (Boustani, Xu, & Xu, 2022), which established the mediating role of blockchain adoption between IoT and continuous usage intention, this study investigates how sociodemographic variables moderate these relationships. The authors use Partial Least Squares Structural Equation Modeling (PLS-SEM) and Partial Least Squares Multi-Group Analysis (PLS-MGA) with the SmartPLS software, analyzing a dataset comprising over a thousand samples in China. The authors' findings demonstrate that age positively moderates the blockchain adoption-continuous usage intention relationship, IoT knowledge positively moderates the citizen empowerment-IoT relationship, while frequency of IoT use negatively moderates the social influence-IoT relationship. These results extend UTAUT theory by revealing boundary conditions of technology adoption in smart cities
AI-Based Human Detection in Indoor Environments using IR-UWB Radar
No full textInternational audienceThis paper is built on a previously developed IR-UWB radar-based detection approach for industrial indoor environments. The proposed signal processing steps resulted in range-Doppler maps of moving objects and humans, which are classified using machine/deep learning algorithms. We evaluate the performance of Support Vector Machines (SVM) and three convolutional neural network (CNN) architectures - AlexNet, GoogLeNet, and ResNet-18 - across various signal-to-noise ratio (SNR) levels. Their effectiveness, assessed in terms of correct classification rate (CCR) and confusion matrix, is compared and discussed in the paper
De la résistance à l’épuisement : 50 ans de conflits (1975-2025) ont-ils eu raison de la « résilience » démographique libanaise ?
No full textInternational audienceOn April 13, 1975, the Lebanon War broke out. Fifty years after its onset, and 35 years after its official conclusion, what demographic legacy can be drawn from this period of conflict? In a country that has not carried out a census for nearly a century, addressing this question involves not only the analysis of demographic data but also an investigative effort akin to forensic inquiry. Lebanon’s demographic developments over the past five decades remain largely obscure. This study seeks to shed light on them by examining the evidence left by those who have previously explored it. Ultimately, the article interrogates the limits of “demographic resilience”: the capacity of populations confronted with prolonged instability –marked by successive crises of varying intensity and nature– to maintain their ability to envision and prepare for a stable medium-term future.Le 13 avril 1975 commençait la guerre du Liban. Cinquante ans après le début de ce conflit, 35 ans après son terme officiel, quel bilan démographique peut-on tirer de ces années troubles ? Dans un pays qui n’a pas organisé de recensement depuis près d’un siècle, tenter de répondre à cette question relève tout autant de l’analyse de données démographiques que de l’enquête au sens policier du terme. La démographie du Liban depuis 50 ans reste une histoire encore bien mystérieuse dont nous essayons de lever le voile à partir des indices laissés par ceux qui se sont déjà penchés dessus. Cet article pose in fine la question des limites des capacités de « résilience démographique » dont sont capables les populations confrontées à des contextes caractérisés par une grande instabilité, où les crises de nature et d’importance inégales se succèdent et affectent la capacité des populations à se projeter sereinement à moyen terme
Cross-Device Distributed Federated Learning Coalition Formation Game for Constrained IoT
No full textInternational audienceEdge computing is an efficient way to help constrained IoT devices by offloading heavy tasks on edge servers, especially computing tasks related to machine learning (ML). Moreover, such devices can only store a limited amount of data because of their reduced capacity. Consequently, ML is bound to be smeared with relatively high error prediction as these devices resort to a small training dataset for their learning. To mend that issue, IoT devices can group in clusters and resort to federated learning (FL) with their pairs in the same cluster or coalition. However, the learned model needs to be transmitted repeatedly over a wireless access network, which is energy consuming. Hence, although learning collectively through FL can reduce the learned model variance, it inflicts a communication cost, dependent on the coalition size, that must be taken into account. Therefore, a cost function is devised astutely by factoring in both the prediction error and communication cost in a learning cluster. Then, a coalition formation game is conceived to minimize the devised cost function. Autonomous IoT devices will engage in the proposed game leading to coalitions of optimal size. Once clusters are formed, distributed FL is applied in any cluster in order to reduce the learning error of participating devices while curbing their communication cost
Sustainable 2-Phenylethanol Production: Co-Cultivation of Yarrowia lipolytica Strains in Mixed Agro-Industrial By-Products
No full textInternational audienceThe bioproduction of 2-phenylethanol (2-PE), a high-value aromatic compound widely used in the fragrance, cosmetic, food and beverage, and pharmaceutical industries, through yeast fermentation offers a sustainable alternative to chemical synthesis and rose extraction. This study explores the fermentation of Yarrowia lipolytica strains using mixed agro-industrial by-products as substrates to produce 2-PE via de novo synthesis, without supplementation with the costly precursor L-phenylalanine. Y. lipolytica strains were genetically engineered to enhance flux through the shikimate pathway and enable the hydrolysis of a broader range of substrates. The culture media consisted solely of a mixture of agro-industrial by-products: sugar beet molasses (SBM), brewer’s spent grain (BSG) pressing extract, and chicory root (CR) pressing extract, serving as the primary carbon and nitrogen sources without the addition of nutrients, minerals, synthetic, complex ingredients, or costly additives. The co-culture approach enhanced substrate utilization, leading to an increase in 2-PE titers, reaching approximately 2.5 g/L 2-PE production after 240 h of fermentation. This study demonstrates the feasibility of integrating co-culture fermentation and agro-industrial waste valorization for sustainable 2-PE production, offering a scalable bioprocess for industrial applications
Holocene Evolution of a High-Altitude Peatland in the Eastern Mediterranean: The Case of the Troodos Peatlands (Cyprus)
No full textInternational audienceThe Levant, identified as a major climate hotspot by the IPCC’s Sixth Assessment Report, is highly sensitive to hydroclimatic changes. Even slight shifts in precipitation or temperature can significantly affect ecosystems, resource availability, and the frequency of extreme weather events. Understanding long-term regional trends is therefore critical to assess past environmental responses and societal resilience. While many paleoenvironmental studies in Cyprus have investigated such changes, they have largely focused on lowland coastal areas near key archaeological sites (Hala Sultan Tekke, Akrotiri) and in the lower reaches of coastal watershed (Tremithos valley). These studies have revealed significant hydroclimatic disruptions over the last 6,000 years BP.However, the island’s topography is a key factor influencing the spatial distribution of temperature, precipitation, and natural habitats across Cyprus, thereby creating distinct Mediterranean mountain environments that differ markedly from the coastal zones. In this context, the minerotrophic peatlands of the Troodos Mountains offer valuable archives for reconstructing past environmental changes in high-altitude settings, thereby helping to fill an important knowledge gapThis study builds on previous pollen-based research by introducing new inorganic proxies and refining the chronological framework of two sediment cores (Almyrolivado and Pasa Livadi) extracted at ~1600 m a.s.l. The poster presents recent analytical results and offers initial interpretations of long-term hydroclimatic variability and landscape dynamics—namely, the alternation between phases of stability (biostasy) and erosion (rhexistasy)—over the past 8,000 years
L'éthique du care au service de l'évolution des pratiques de GRH socialement responsables : cas des salariés aidants dans les structures médico-sociales
No full textNational audienceDans cette communication, nous explorons comment l'éthique du care peut enrichir la dimension socialement responsable des pratiques de Gestion de Ressources Humaines destinées aux salariés aidants dans le secteur médico-social. À travers une analyse de 102 accords d'entreprise et, plus précisément, de 13 accords du secteur médico-social, nous avons identifié 28 pratiques de GRH qui peuvent être mobilisées par le salarié aidant pour l'accompagner dans son rôle d'aidant. Il ressort que, même si ces pratiques témoignent d'une écoute des besoins des salariés aidants, elles restent réactives aux obligations légales et s'inscrivent plus dans une logique de protection que dans celle d'un bon care organisationnel. Nous soutenons que repenser les politiques de GRH en s'appuyant sur les trois éléments essentiels à l'évaluation des pratiques de care proposés par Tronto (2010) – à savoir la finalité du care, le particularisme et les relations de pouvoir - permettrait de développer un cadre de réflexion propice à la mise en œuvre de pratiques de GRH plus socialement responsables et mieux adaptées aux besoins diversifiés des salariés aidants
Diesel generator exhaust emissions : Chemical characterization and cytotoxicity in bladder spheroids
No full textInternational audienceDiesel generators, widely used in developing countries, compensating for long power outages and blackouts, are significant sources of air pollution. In this study, diesel exhaust particulate matter (DEPM) samples were collected from two midsize generators operating in Beirut by cascade impaction, and gravimetrically analyzed for size. The smallest fraction captured on quartz filter was then chemically characterized for its constituents, and examined for its cytotoxicity on 2D and 3D human uroepithelial cell cultures. Results showed that 87 % of collected PM are quasi-ultrafine (<0.33 μm in diameter), and marked high emissions of organic and elemental carbon (OC/EC), elements and metals, particularly Ca, Fe, S, Al, and Ti, and polyaromatic hydrocarbons (PAHs), mainly Benzo[g,h,i]perylene and Dibenzo[a,h]anthracene, as well as high emissions of dioxins, furans and polychlorinated biphenyls (PCBs), particularly OCDD, 1,2,3,4,6,7,8 HpCDF, and PCB118. In addition, in vitro testing showed decreased proliferation, viability, and spheroid formation ability only at high concentrations. In conclusion, DEPM from domestic generators consists of a wide panel of potent toxicants, notably genotoxic, carcinogenic, and endocrine disrupting compounds. Additionally, in vitro results provide a solid basis to further examine the potential contribution of DEPM to bladder tumorigenesis in established cell culture models