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A SEM-based method to determine the mineralogical composition and the particle size distribution of suspended sediment

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International Journal of Sediment Research 2019年第2期34卷 85-94页

作者： Sylvain Pinet Bruno lartiges Jean-Michel Martinez Sylvain Ouillonc University of Toulouse (Paul Sabatier) Geosciences Environment ToulouseCNRS(Centre National de la Recherche Scientifique)IRD(Institut de Recherche pour le Développement) instituto de Geosciencias Universidade de BrasiliaCampus Universitario Darcy RibeiroICC Centro University of Toulouse LEGOS(Laboratoire d'Etudes en Géophysique et Océanographie Spatiales)

A robust method for characterizing the mineralogy of suspended sediment in continental rivers is *** encompasses 3 steps:the filtration of a few milliliters of water,measurements of X-ray energy dispersive spectra using Scanning Electron Microscopy(SEM),and robust machine learning tools of *** method is applied to suspended particles collected from various Amazonian rivers.A total of more than 204,000 particles were analyzed by SEM-EDXS(Energy Dispersive X-ray Spectroscopy),*** 15,700 particles per sampling station,which lead to the identification of 15 distinct groups of mineralogical *** size distribution of particles collected on the filters was derived from the SEM micrographs taken in the backscattered electron imaging mode and analyzed with ImageJ *** determination of the main mineralogical groups composing the bulk sediment associated with physical parameters such as particle size distribution or aspect ratio allows a precise characterization of the load of the terrigenous particles in rivers or *** the case of the Amazonian rivers investigated,the results show that the identified mineralogies are consistent with previous studies as well as between the different samples *** method enabled the evolution of grain size distribution from fine to coarse material to be described in the water *** about hydrodynamic sorting of mineral particles in the water column are also briefly *** proposed method appears well suited for intensive routine monitoring of suspended sediment in river systems.

关键词： Mineralogy Scanning Electron Microscopy Suspended sediment Machine learning Particle size distribution

Retinoid receptor-related orphan receptor alpha： a key gene setting brain circuits

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Neural Regeneration Research 2018年第5期13卷 791-794页

作者： Tania Vitalis Jean Mariani PROTECT Institut National de la Santé et de la Recherche Médicale Université Paris Diderot Paris France Université Pierre et Marie Curie Sorbonne Université Paris France Centre national de la recherche Scientifique Unité Mixte de Recherche 8256 Institut de Biologie de Paris Seine (IBPS) Biological adaptation and ageing (B2A) Team Brain Development Repair and Ageing Paris France Assistance Publique - Hopitaux de Paris Départements Hospitalo-Universitaires FAST Institut de la Longévité Ivry-Sur-Seine France

The retinoid receptor-related orphan receptor alpha（RORα） is thought to act as a constitutive activator of transcription by binding to the ROR response element（RORE） of target genes. Several mouse models in which RORα is defective have revealed the decisive roles of RORα on the development, maturation and neuroprotection of various cerebral regions including the cerebellar and somatosensory systems. We have recently shown that RORα is needed for accurate thalamic sensory system organization and somatosensory cortex development. The phenotype of various RORα deficient mice models（staggerer mutant or mouse lacking RORα in specific somatosensory regions） is, in part, reminiscent of what has been described in mice lacking thyroid hormone triiodothyronine（T3）. As in in vitro studies or in other models, our studies strongly suggest that the T3/RORα-pathway, among others, is in part responsible for the staggerer phenotype. We have indeed identified some genes that were both regulated by T3 and RORα and that are known to be implicated in the cerebellar or somatosensory system development. Moreover, several groups have shown that RORα is at the crossroad of many biological processes and pathologies, including psychiatric and degenerative disorders. In particular, defective RORα-signalling has been demonstrated in humans to be associated with the emergence of autistic-like disorders. We believe that determining the appropriate amount of RORα activity could be crucial in detecting and preventing the emergence of specific brain diseases.

关键词： cerebellum cerebral cortex development maturation neuroprotection psychiatric disorders somatosensory system

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Differences and similarities between mesenchymal stem cell and endothelial progenitor cell immunoregulatory properties against T cells

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World Journal of Stem Cells 2021年第8期13卷 971-984页

作者： Mehdi Razazian Maryam Khosravi Sheyda Bahiraii Georges Uzan Sara Shamdani Sina Naserian institut national de la santéet de la recherche médicale(Inserm)UnitéMixte de recherche-Inserm-Ministère de la Défense 1197 Hôpital Paul BrousseVillejuif 94800France Microenvironment&Immunity Unit Institut PasteurParis 75724France institut national de la santéet de la recherche médicale(Inserm)Unit 1224 Paris 75724France Department of Pharmacognosy University of ViennaVienna 1090Austria Paris-Saclay University Villejuif 94800France CellMedEx Saint Maur Des Fossés 94100France

Bone-marrow-derived mesenchymal stem cells and endothelial progenitor cells have some interesting biological properties that make them unique for cell therapy of degenerative and cardiovascular *** both cell populations have been already studied and used for their regenerative potentials,recently their special immunoregulatory features have brought much more *** stem cells and endothelial progenitor cells have both proangiogenic functions and have been shown to suppress the immune response,particularly T cell proliferation,activation,and cytokine *** makes them suitable choices for allogeneic stem cell ***,these two cells do not have equal immunoregulatory *** elements including their extraction sources,age/passage,expression of different markers,secretion of bioactive mediators,and some others could change the efficiency of their immunosuppressive ***,to our knowledge,no publication has yet compared mesenchymal stem cells and endothelial progenitor cells for their immunological interaction with T *** review aims to specifically compare the immunoregulatory effect of these two populations including their T cell suppression,deactivation,cytokine production,and regulatory T cells induction ***,it evaluates the implications of the tumor necrosis factor alpha-tumor necrosis factor receptor 2 axis as an emerging immune checkpoint signaling pathway controlling most of their immunological properties.

关键词： Endothelial Progenitor Cells Mesenchymal Stem Cells T cells Immunosuppression Immunoregulation TNFα-TNFR2 signaling pathway

Design of sediment detention basins: Scaled model experiments and application

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International Journal of Sediment Research 2021年第1期36卷 136-150页

作者： Anita Moldenhauer-Roth Guillaume Piton Sebastian Schwindt Mona Jafarnejad Anton J.Schleiss Hydraulic Constructions Platform (PL-LCH) Swiss Federal Institute of Technology Lausanne (EPFL) Université Grenoble Alpes Institut National de Recherche en Sciences et Technologies Pour L'environnement et L'agriculture (IRSTEA)

Sediment detention basins are implemented on mountain rivers to trap solid material that may aggravate the flooding of downstream ***,retention structures built in the past may unnecessarily retain sediment during non-hazardous flood events,resulting in high maintenance costs and sediment deficit *** addition,the so-called spontaneous self-flushing of previously retained sediment during floods has occasionally been *** research suggests to design sediment detention basins for controlling sediment passage with a guiding channel across the deposition area upstream of a hybrid *** barriers consist of a check dam with a slot orifice and an upstream bar screen with a bottom clearance in order to benefit from a combined mechanical-hydraulic retention *** present paper enhances this pioneering research with the help of new experimental data,including a wide range of sediment mixtures and large wood,as well as variable barrier *** design criteria are provided regarding the bar screen and the basin storage *** functionality of the enhanced concept for sediment detention is illustrated by a case study on a physical model:the protection of the Villard-Bonnot village(France) against torrential hazards.

关键词： Sediment continuity Sediment trap Bedload Open check dam Sediment flushing

Optimizing Fertilizer Use by Smallholder Farmers and Economic Returns to Maize in Semi-arid Niger

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Journal of Agricultural Science and Technology(B) 2018年第2期8卷 85-96页

作者： Nouri Maman Gonda Abdou Maman Garba institut national de la recherche agronomique du Niger (INRAN) Département des Culture Pluviales Maradi BP 240 Niger institut national de la recherche agronomique du Niger (INRAN) Département de Gestion des Ressources Naturelles Niamey BP 429 Niger

Maize （Zea mays L.） is an important food crop in Niger, but low and irregular rainfall combined with sandy soils having low fertility level limit productivity. A two-year study was conducted at institut national de recherche agronomique du Niger （INRAN） stations in Tarna/Maradi and Bengou/Gaya in 2014 and 2015 in order to evaluate maize agronomic and economic fertilizer use efficiency. The experimental design was a randomised complete block design （RCBD） with three replications. Results indicate higher effect of fertilizer in 2015 compared to 2014. At low N rates 20 kg N/ha and 40 kg N/ha, application of 20 kg P/ha increased maize grain yield across locations and years. The highest agronomic efficiency of N （AEN） was recorded with 60 kg N/ha in 2015 at Bengou and Tarna with 9.65 kg and 14.05 kg grain yield per kg of applied N, respectively. At Tarna, the low N rates of 20 kg N/ha and 40 kg N/ha recorded important AEN of more than 12 kg yield increases per kg of applied N. The highest rainfall use efficiency （RUE） of 6.13 kg/year/mm was obtained with application of 80 kg/ha N, 0 kg/ha P and 40 kg/ha N, 20 kg/ha P in 2015 at Tarna. Without P, the highest value cost ratio （VCR） value of 4.31 was recorded at Tarna in 2015 with 60 kg/ha N, and the lowest value of 0.08 at Bengou in 2014 with 20 kg/ha N. Based on VCR and RUE derived from this study, the optimal fertilizer recommendation for maize in the semi-arid conditions of Niger could be 40 kg/ha N, 20 kg/ha P and 0 kg/ha K.

关键词： Maize agronomic efficiency semi-arid fertilizer recommendation nutrient use efficiency rain use efficiency profitability of fertilizer use.

Multi-factor principle for electrolyte additive molecule design for facilitating the development of electrolyte chemistry

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Green Energy & Environment 2022年第1期7卷 1-2页

作者： Shuhui Sun institut national de la recherche Scientifique(INRS)-Center for Energy Materials and TelecommunicationsVarennesQuébec J3X 1S2Canada

When I read the paper“Electrolytes enriched by potassium perfluorinated sulfonates for lithium metal batteries”from *** Ma’s group,which was published in Science Bulletin(***/10.1016/***.2020.09.018),I felt excited as presented a multi-factor principle for applying potassium perfluorinated sulfonates to suppress the dendrite growth and protect the cathode from the viewpoint of electrolyte *** effects of these additives are revealed through experimental results,molecular dynamics simulations and first-principle ***,it involves the influence of additives on Li^(+)solvation structure,solid electrolyte interphase(SEI),Li growth and *** the guidance of the multi-factor principle,every part of the additive molecule should be utilized to regulate *** multifactor principle for electrolyte additive molecule design(EAMD)offers a unique insight on understanding the electrochemical behavior of iontype electrolyte additives on both the Li metal anode and high-voltage *** these regards,I would be delighted to write a highlight for this innovative work and,hopefully,it may raise more interest in the areas of electrolyte additives.

关键词： Lithium metal batteries Multi-factor principle Electrolyte additives Dendrite growth suppression Lithium protection

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Th17 cells, pathogenic or not？ TGF-β3 imposes the embargo

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Cellular & Molecular Immunology 2013年第2期10卷 101-102页

作者： Meenu Sharma Unite 872 Institut National de la Sante et de la Recherche Medicale Paris France Universite de Technotogie de Compiegne Compiegne France Centre de recherche des Cordeliers Equipe 16- Immunopathology and therapeutic immunointerven- tion Universite Pierre et Marie Curie Paris France Universite Paris Descartes Pads France nternational Associated laboratory IMPACT (institut national de la Sante et de la recherche Medicale France--Indian Council of Medical Research India) National Institute of Immunohaematology Mumbai India

Th17 cells that express lineage-spe- cific transcription factor RORC inhuman （and RORTt in mice） and pro- duce cytokines IL-17A, IL-17F, IL-21, GM-CSF and IL-22, constitute distinct subset of CD4＋ T cells.

关键词： pathogenic TGF-β3 embargo

Risk Factors for Neonatal Mortality at the institute of Nutrition and Child Health of the Donka/Guinea-Conakry national Hospital

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Open Journal of Pediatrics 2024年第2期14卷 327-337页

作者： Bangoura Mmah Aminata Kolié Ouo Ouo Camara Salématou Hassimiou Baldé Mariama Bangoura Kaba Diop Mamadou Moustapha Camara Emmanuel Diallo Fatoumata Binta Doukouré Mamadou Aliou Mamadou Mouctar Sow Bémy Pé Néabey institut de Nutrition et de Santé de l’Enfant Conakry Guinea Service de Pédiatrie Hô pital National Donka Conakry Guinea Service de Pédiatrie Hô pital National d’Ignace Deen Conakry Guinea

Introduction: The birth of a baby is a moment of joy and celebration. However, the neonatal period is a very delicate phase of life. Neonatal mortality rates remain high in low-income countries. In Guinea, after 20 years, this rate has fallen from 34.2% in 1998 to 32% in 2018. Objective: To identify the main risk factors for neonatal mortality. Methods: This was an observational, analytical case-control study, lasting 6 months from January 1 to June 30, 2019, conducted at the institut de Nutrition et de la Santé de l’Enfant (INSE) at Donka national Hospital. Results: We collected 242 cases and 242 controls, i.e. a total of 484 records. 748 patients were registered, with 32.35% deaths. 82.86% of deaths occurred in the early neonatal period. Statistical analysis revealed the main risk factors: prematurity (RQ 7.39 95% CI 3.27 - 16.61 p = 0.0000003), hypothermia (RQ 2.29 95% CI 1.51 - 3.46 p = 0.0001), acute fetal distress (RQ 2.13 95% CI 1.33 - 3.43 p = 0.0016), low birth weight (QR 1.91 95% CI 1.12 - 3.24 p = 0.016), home birth (QR 3.26 95% CI 1.25 - 8.46 p = 0.015). Conclusion: Neonatal mortality is a health problem in the INSE neonatology department. To reduce the mortality rate in this referral facility, it is essential to equip it and provide ongoing training for staff.

关键词： Neonatal Mortality INSE Guinea-Conakry

Key drivers of ecosystem recovery after disturbance in a neotropical forest Long-term lessons from the Paracou experiment, French Guiana

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Forest Ecosystems 2018年第1期5卷 13-27页

作者： bruno hérault camille piponiot cirad umr ecofog (agro paristech cnrs inra université des antillesuniversité de la guyane) campus agronomique97310 kouroufrench inphb (institut national polytechnique félix houphouet boigny) yamoussoukroivorycoast université de la guyane umrecofog(agro paristech cirad cnrs inra université des antilles) campus agronomique97310 kouroufrench guianafrance

Background： Natural disturbance is a fundamental component of the functioning of tropical rainforests let to natural dynamics, with tree mortality the driving force of forest renewal. With ongoing global （i.e. land-use and climate） changes, tropical forests are currently facing deep and rapid modifications in disturbance regimes that may hamper their recovering capacity so that developing robust predictive model able to predict ecosystem resilience and recovery becomes of primary importance for decision-making：（i） Do regenerating forests recover faster than mature forests given the same level of disturbance？（ii） is the local topography an important predictor of the post-disturbance forest trajectories？（iii） Is the community functional composition, assessed with community weighted-mean functional traits, a good predictor of carbon stock recovery？（iv） How important is the climate stress （seasonal drought and/or soil water saturation） in shaping the recovery trajectory？ Methods： Paracou is a large scale forest disturbance experiment set up in 1984 with nine 6.25 ha plots spanning on a large disturbance gradient where 15 to 60% of the initial forest ecosystem biomass were removed. More than 70,000 trees belonging to ca. 700 tree species have then been censused every 2 years up today. Using this unique dataset, we aim at deciphering the endogenous （forest structure and composition） and exogenous （local environment and climate stress） drivers of ecosystem recovery in time. To do so, we disentangle carbon recovery into demographic processes （recruitment, growth, mortality fluxes） and cohorts （recruited trees, survivors）. Results： Variations in the pre-disturbance forest structure or in local environment do not shape significantly the ecosystem recovery rates. Variations in the pre-disturbance forest composition and in the post-disturbance climate significantly change the forest recovery trajectory. Pioneer-rich forests have slower recovery rates than assemblages of lat

关键词： Ecosystem modeling Tropical forests Carbon fluxes Ecological resilience Climate change Amazonia

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