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Incidence de l'adoption des droits de douane par le Président Trump
No full textInterview à la radio (NRJ et Nostalgie) à destination du grand public sur l'incidence des politiques douanières du Président Trum
Unpacking the meeting load paradox: impacts on engagement and burnout across work arrangements
Get PDFpeer reviewedPurpose-This paper aims to explore how workplace meetings, work arrangements and their interactions relate to employee engagement and burnout. Design/methodology/approach-This paper draws from the conservation of resources theory to hypothesize the relationships between the antecedent and outcome variables. To test the hypotheses, this study analyzes a structural equation model based on panel survey data from 1,137 respondents. Findings-This study finds that meeting load is positively related to burnout, but not to engagement in general. Also, relative to the hybrid work arrangement, engagement is lower in the in-person only arrangement and burnout is higher in the remote-only arrangement. As to the interaction effects, meeting load in the on-site work arrangement situation relates positively to both engagement and burnout. Practical implications-The findings provide valuable insight for practitioners in an increasingly complex and competitive environment, as they can be factored into debates around policies for meetings and work arrangements. Originality/value-The COVID-19 pandemic created a seismic shift in the way people work: it released an avalanche of workplace meetings; it normalized hybrid work arrangements; and it heightened attention on work outcomes. This study lies at the intersection of these three important trends
Uncorrelated Age-Related Changes in Visuo-Spatial Working Memory Binding and Thermoregulation.
Get PDFpeer reviewedAgeing is associated with alterations in circadian rhythms and thermoregulation, contributing to a fragmentation of the sleep-wake cycle and possibly age-related changes in cognitive performance. In this study, we investigated the relationship between visuo-spatial working memory (vsWM) performance and thermoregulation in young (18-34 years) and old (64-84 years) healthy human adults. Variations in the distal-proximal skin temperature gradient (DPG) were continuously monitored over the 24 h cycle in a field setting. vsWM was assessed during morning (09:00) and evening sessions (17:00) using an object-location binding task. As expected, a reduced circadian DPG amplitude was observed in old as compared to young participants. Likewise, old participants produced more errors than the young ones in object identification and location, suggesting reduced vsWM ability. Notwithstanding this, no significant association was found between circadian DPG modulation and vsWM performance, nor between testing time-of-day and cognitive performance. Further research is needed to explore environmental factors and the timing of peak circadian rhythms to better understand the interplay between circadian biology and cognitive ageing
Quantitative and Qualitative Variations in Eucalyptus Essential Oils Depending on Species and the Cultivation Location
Get PDFpeer reviewedObjectives: This study examined the impact of various abiotic factors, specifically temperature and precipitation, on the yield and composition (volatile profile) of essential oils (EO) from four Eucalyptus species, including Eucalyptus salmonophloia, Eucalyptus torquata, Eucalyptus lesouefii and Eucalyptus astringens. Additionally, the antimicrobial properties of these EO were assessed. Methods: The species were collected from five arboreta in Tunisia belonging to two climatic conditions (arid and semi-arid). EOs were extracted from the leaves using the hydrodistillation technique and analyzed by gas chromatography coupled with mass spectrometry (GC-MS). The antimicrobial activity was evaluated by measuring the diameters of inhibition zones using the agar well diffusion method and by determining the minimum inhibitory concentrations (MICs). Results: The yield of Eucalyptus EOs varied from 0.12% to 4.63% (w/w, dry weight) depending on the species and the plant's growing location. 1,8-cineole (29.71% to 67.16%) was by far the major compounds in EOs of E. salmonophloia, E. lesouefii and E. astringens, however E. torquata was torquatone chemotype (33.41% to 44.78%). In general, the aridity increased the extraction yield of EO. Higher temperature and lower rainfall conditions enhanced the production of key compounds such as, 1,8-cineole and ɑ-pinene, however, it decreases others compounds like spathulenol and viridiflorol. A notable antimicrobial activity was observed against all microbial strains tested, demonstrating both microbicidal and microbiostatic effects, particularly against Escherichia coli, Serratia marcescens, and Candida tropicalis. The EOs derived from the studied Eucalyptus species represent a valuable source of bioactive compounds, including 1,8-cineole, ɑ-pinene, spathulenol, and β-eudesmol. These compounds contribute to the oils’ significant antimicrobial efficacy, offering the additional advantage of being a natural product. Conclusion: Our findings reinforce the notion that environmental factors may serve as a limiting factor in the production and availability of Eucalyptus EO for medicinal and industrial applications
From benthic functional biodiversity to the mapping of ecosystem functions: a case study over the Black Sea northwestern shelf
No full textBenthic biodiversity is of global significance for the provision of ecosystem services and the mediation of global biogeochemical cycles. For instance, the macrozoobenthos plays a key role in marine carbon and nutrient cycling. Yet, current ocean biogeochemical models oversimplify or ignore life at the seafloor and its variability. The absence of detailed spatial distribution of the functions of the benthos, at large-scale (e.g., coastal and shelf scales), partly explains why benthic life characteristics are not taken into account in model formulation of benthic-pelagic exchanges. This lack of knowledge critically prevents our ability to predict the impact of climate change on the functioning of benthic life and its feedback on marine ecosystem and the biogeochemical budget of carbon, nitrogen, oxygen, phosphorus.Here, we propose to scale up benthic biodiversity data from field sampling to the evaluation of ecosystem functions at large-scale (e.g., carbon sequestration, denitrification), relevant for ecosystem-based management. In our study, we include mechanistic and statistical models to map functional benthic biodiversity in relation to environmental drivers, and ultimately to incorporate its variability into current ocean model.In more details, we compile macrozoobenthos occurrence from 210 sampling stations, covering constrained benthic habitats, over the northwestern shelf of the Black Sea. We use a functional approach of the biodiversity meaning that species are defined by their traits (e.g., dwelling depth and mobility) with an effect on ecosystem functioning. Then, species traits are upscaled at the community level by crossing species observations and their traits. From punctual values, we map continuous distribution of traits as a proxy of ecological processes (e.g., biomixing and biodeposition), precursors of ecosystem functions. We use a neural network to reconstruct maps of traits by linking them to environmental drivers, provided by a biogeochemical model, at high temporal and spatial resolution, run in an operational mode by Copernicus Marine Service (CMEMS). We use a combination of dozen biogeochemical (e.g., bottom oxygen and flux of organic carbon to the bottom) and physical drivers (e.g., bottom temperature and shear stress) as preliminary predictors of the distribution of traits. Then, we choose the best selection of predictors for our trait distribution models.Our key findings show that bottom oxygen and stock of organic carbon are strong predictors for the distribution of traits at shelf-scale. Specifically, areas with high suspended materials and nutrients, such as near the Danube Delta, show deeper burrowing depths and greater mobility in benthic communities meaning potentially higher impact on sediment biomixing. In contrast, permanently hypoxic waters are characterized by very low sediment biomixing potential and very low benthic biodiversity. Thanks to the maps of ecosystem functions, we adapt the parametrization of a current diagenetic model (e.g., depth of mixed layer, bioturbation coefficient) to incorporate the variability of the functional benthic biodiversity. A diagenetic model constrained by seafloor biodiversity, will constitute a significant step for the development of ocean models considering the impact of environmental changes on benthic life and its ability to deliver key marine ecosystem functions.14. Life below wate
Intégrité et conflit d’intérêts : financement de la recherche publiée en libre accès et dans les revues hybrides ? Le cas de la chirurgie cardiaque
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Biodiversité et Territoires
Get PDFCette conférence dresse un état des lieux alarmant de la biodiversité mondiale et locale, en insistant sur l’ampleur de la diversité biologique (plus de 2 millions d’espèces identifiées, dont 50 % d’insectes), l’incertitude sur le nombre total d’espèces, et l’accélération dramatique de leur disparition. Elle met en évidence les causes principales du déclin (agriculture intensive, artificialisation des sols, espèces exotiques envahissantes, changement climatique), l’importance des services écosystémiques, et les engagements de la Wallonie et de l’UE en faveur de la conservation (restauration des habitats, protection de 30 % du territoire, intégration de la biodiversité dans tous les secteurs). L’accent est mis sur l’urgence d’actions concrètes et ambitieuses
Use of Human Acute Myeloid Leukemia Cells to Study Graft-Versus-Leukemia Immunity in Xenogeneic Mouse Models of Graft-Versus-Host Disease.
No full textpeer reviewedAllogeneic hematopoietic cell transplantation (allo-HCT) is the main therapeutic approach for patients with high-risk acute myeloid leukemia (AML), but the rate of relapse remains high and is associated with poor outcomes. Discovering new approaches to maximize the graft-versus-leukemia (GVL) effects while mitigating graft-versus-host disease (GVHD) should therefore be pursued. Because of the difficulties in modeling AML in mice, patient-derived xenotransplantations (PDXs) in immunodeficient NOD-scid-IL2rgnull (NSG) mice are preferred to study the GVL effects. In PDX, AML is typically induced through the intravenous injection of cell lines or leukemic blasts obtained from patients. GVHD and GVL effects are induced by (co)-injecting human T cells or peripheral blood mononuclear cells (PBMCs). While this approach enables the induction of systemic leukemia, notably developing in the spleen and bone marrow of the animals, it can also be associated with difficulties in monitoring the disease, notably by flow cytometry. This can be circumvented by using luciferase-expressing AML cells or transplanting the leukemic cells in Matrigel to generate solid tumors that are easier to monitor. Here, we provide detailed instructions on how to prepare human PBMCs and leukemic cells, transplant them, and monitor the disease in NSG mice