Resource competition affects plankton community structure; evidence from trait-based modeling

Understanding the phenology of phytoplankton species is a challenge and despite a lot of theoretical work on competition for resources, this process is under-represented in deterministic models. To study the main driver of the species selection, we used a trait-based model that keeps phenotypic variability through physiological trait parameterization. Next, we validated the results by using the toxic dinoflagellate Alexandrium minutum which is a toxic species. Due to their monitoring, we show that harmful algae are ideal models for studying ecological niches and for contributing to this more global challenge. As a first step, a dimensionless model of an estuary (France) was built with water temperature and water exchanges deduced from a hydro-dynamic model. The biological parametrization takes into account the size (from pico- to microphytoplankton) and the type of assimilation. The results show that temperature, competition for nutrients and dilution are important factors regulating the community structure and Alexandrium minutum dynamics (more especially the bloom initiation and magnitude). These drivers contribute to the determination of the ecological niche of A. minutum, influence the shape of its blooms and provide potential explanations of its interannual variability. This approach makes the community structure more flexible in order to study how environmental forcings could drive its evolution

Polymeric nanocapsules prevent oxidation of core-loaded molecules: evidence based on the effects of docosahexaenoic acid and neuroprostane on breast cancer cells proliferation

International audienceBackground:Nanocapsules, as a delivery system, are able to target drugs and other biologically sensitive moleculesto specific cells or organs. This system has been intensively investigated as a way to protect bioactives drugs frominactivation upon interaction with the body and to ensure the release to the target. However, the mechanism ofimproved activity of the nanoencapsulated molecules is far from being understood at the cellular and subcellularlevels. Epidemiological studies suggest that dietary polyunsaturated fatty acids (PUFA) can reduce the morbidityand mortality from breast cancer. This influence could be modulated by the oxidative status of the diet and it hasbeen suggested that the anti-proliferative properties of docosahexaenoic acid (DHA) are enhanced by pro-oxidantagents Methods:The effect of encapsulation of PUFA on breast cancer cell proliferation in different oxidative mediumwas evaluated in vitro. We compared the proliferation of the human breast cancer cell line MDA-MB-231 and ofthe non-cancer human mammary epithelial cell line MCF-10A in different experimental conditions. Results:DHA possessed anti-proliferative properties that were prevented by alpha-tocopherol (an antioxidant) andenhanced by the pro-oxidant hydrogen peroxide that confirmsthat DHA has to be oxidized to exert its anti-proliferativeproperties. We also evaluated the anti-proliferative effects of the 4(RS)-4-F4t-neuroprostane, a bioactive, non-enzymaticoxygenated metabolite of DHA known to play a major role inthe prevention of cardiovascular diseases. DHA-loadednanocapsules was less potent than non-encapsulated DHA while co-encapsulation of DHA with H2O2maintainedthe inhibition of proliferation. The nanocapsules slightly improves the anti-proliferative effect in the case of4(RS)-4-F4t-neuroprostane that is more hydrophilic than DHA. Conclusion:Overall, our findings suggest that the sensitivity of tumor cell lines to DHA involves oxidized metabolites.They also indicate that neuroprostane is a metabolite participating in the growth reducing effect of DHA, but it is not thesole. These results also suggest that NC seek to enhance the stability against degradation, enhance cellular availability,and control the release of bioactive fatty acids following their lipophilicities

Reproducible and relocatable regional ocean modelling: Fundamentals and practices

In response to an increasing demand for bespoke or tailored regional ocean modelling configurations, we outline fundamental principles and practices that can expedite the process to generate new configurations. The paper develops the principle of Reproducibility and advocates adherence by presenting benefits to the community and user. The elements to this principle are reproducible workflows and standardised assessment, with additional effort over existing working practices being balanced against the added value generated. The paper then decomposes the complex build process, for a new regional ocean configuration, into stages and presents guidance, advice and insight on each component. This advice is compiled from across the user community, is presented in the context of NEMOv4, though aims to transcend NEMO version. Detail and region specific worked examples are linked in companion repositories and DOIs. The aim is to broaden the user community skill base, and to accelerate development of new configurations in order to increase available time exploiting the configurations

Rapport d'etude Prospect'Kid 2030

Commissioned by Novachild (EU consortium for the Children industry), coordinated by the Comptoir Prospectiviste, supported by an audit of current opportunities and challenges are faced in children education and material culture. A speculative approach provided by a group of experts across disciplines (sociology, marketing, anthropology, education, childhood studies, Health) and sectors (Higher Education, children industry, healthcare) underpins this report and recommends exploratory avenues for policy makers and the industry. Dr Aude Le Guennec is one of these experts for children's material culture (Design Anthropology, CHildhood Studies). Institutional partners: University of Angers (ENJEUX), Design School Nantes (Food Lab), University of Poitiers (IAE), CHU Nantes, Ville de Cholet

The cerebral network of COVID-19-related encephalopathy: a longitudinal voxel-based 18F-FDG-PET study

International audienc

The Bristol CMIP6 Data Hackathon

The Bristol CMIP6 Data Hackathon formed part of the Met Office Climate Data Challenge Hackathon series during 2021, bringing together around 100 UK early career researchers from a wide range of environmental disciplines. The purpose was to interrogate the under-utilised but currently most advanced climate model inter-comparison project datasets to develop new research ideas, create new networks and outreach opportunities in the lead up to COP26. Experts in different science fields, supported by a core team of scientists and data specialists at Bristol, had the unique opportunity to explore together interdisciplinary environmental topics summarised in this article

The wide spectrum of COVID-19 neuropsychiatric complications within a multidisciplinary centre

International audienceA variety of neuropsychiatric complications has been described in association with COVID-19 infection. Large scale studies presenting a wider picture of these complications and their relative frequency are lacking. The objective of our study was to describe the spectrum of neurological and psychiatric complications in patients with COVID-19 seen in a multidisciplinary hospital centre over 6 months. We conducted a retrospective, observational study of all patients showing neurological or psychiatric symptoms in the context of COVID-19 seen in the medical and university neuroscience department of Assistance Publique Hopitaux de Paris-Sorbonne University. We collected demographic data, comorbidities, symptoms and severity of COVID-19 infection, neurological and psychiatric symptoms, neurological and psychiatric examination data and, when available, results from CSF analysis, MRI, EEG and EMG. A total of 249 COVID-19 patients with a de novo neurological or psychiatric manifestation were included in the database and 245 were included in the final analyses. One-hundred fourteen patients (47%) were admitted to the intensive care unit and 10 (4%) died. The most frequent neuropsychiatric complications diagnosed were encephalopathy (43%), critical illness polyneuropathy and myopathy (26%), isolated psychiatric disturbance (18%) and cerebrovascular disorders (16%). No patients showed CSF evidence of SARS-CoV-2. Encephalopathy was associated with older age and higher risk of death. Critical illness neuromyopathy was associated with an extended stay in the intensive care unit. The majority of these neuropsychiatric complications could be imputed to critical illness, intensive care and systemic inflammation, which contrasts with the paucity of more direct SARS-CoV-2-related complications or post-infection disorders