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Bifunctional oxygen electrode cobalt–nickel sulfides catalysts originated from intercalated LDH precursors

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Journal of Energy Chemistry 2022年第11期31卷 376-386,I0010页

作者： Xiaofei Gong Haihong Zhong Luis Alberto Estudillo-Wong nicolas alonso-vante Yongjun Feng Dianqing Li State Key Laboratory of Chemical Resource Engineering Beijing Engineering Center for Hierarchical CatalystsCollege of ChemistryBeijing University of Chemical TechnologyBeijing 100029China Departamento de Sociedad y Política Ambiental CIIEMADInstituto Politécnico NacionalCalle 30 de junio de 1520Alcaldía GAMC.P.07340 CDMXMexico IC2MP UMR-CNRS 7285University of PoitiersF-86073 Poitiers CedexFrance

Bimetallic cobalt-nickel sulfide nanoparticles anchored on S-,N-codoped holey carbon nanosheets(CoNiS-T@NCFs)with a hydrangea-like morphology,were synthesized via a confinement synthesis route,in which an intercalated LDH precursor was subjected to the interlayer-confined carbonization and host-layer sulfurization.The phase transformation and structure evolution(e.g.,atom site occupancy,crystallite size,and cell volume)of the CoNi-S-T@NCFs electrocatalysts,as a function of sulfurization temperatures,were confirmed by X-ray diffraction and Rietveld analyses.The sulfur vacancies effectively enhance the electrocatalytic activity,while the synergistic effect of(Co,Ni)7 S8 alloy and S,N-codoped carbon matrix facilitates the electron transfer and accelerates reaction kinetics,making CoNi-S-900@NCFs an efficient and stable bifunctional electrocatalyst for oxygen reduction reaction(ORR).The rich highvalence Co(Ⅲ)and Ni(Ⅲ)of CoNi-S-900@NCFs facilitates the in-situ transformation of the metal(oxy)hydroxides intermediates with high catalytic activity for oxygen evolution reaction(OER).Thus,with a bifunctional parameter,ΔE,of 0.75 V(E_(j=10,OER)-E_(1/2,ORR)),this electrocatalyst slightly outperforms the state-of-the-art commercial Pt/C+RuO_(2)/C catalyst(ΔE=0.76 V)in alkaline medium.This work demonstrates the influence that the sulfurization temperature has on the relationship between the structure and electrocatalytic performance of bimetallic sulfides prepared by the synthesis strategy using the intercalated LDH precursor.This strategy can be extended to prepare other chalcogenides with binary or ternary transition metals.

关键词： Bimetallic sulfides Confinement synthesis LDHs ORR OER

Oxygen vacancies engineering by coordinating oxygen-buffering CeO_(2) with CoO_(x) nanorods as efficient bifunctional oxygen electrode electrocatalyst

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Journal of Energy Chemistry 2021年第8期30卷 615-625,I0013页

作者： Haihong Zhong Luis Alberto Estudillo-Wong Yuan Gao Yongjun Feng nicolas alonso-vante State Key Laboratory of Chemical Resource Engineering Beijing Engineering Center for Hierarchical CatalystsCollege of ChemistryBeijing University of Chemical TechnologyNo.15 Beisanhuan East Road100029 BeijingChina IC2MP UMR-CNRS 7285University of PoitiersF-86022 Poitiers CedexFrance Departamento de Sociedad y Política Ambiental CIIEMADInstituto Politécnico NacionalCalle 30 de junio de 1520Alcaldía GAMC.P.07340 CDMXMexico Anqing Research Institute Beijing University of Chemical TechnologyNo.8 Huanhu West RoadHigh-Tech DistrictAnqing 24600China

CeO_(2)decorated CoOx rod-like hybrid,supported onto holey reduced graphene(CoOx/CeO_(2)/RGO)composite,was fabricated via a surfactant-assisted route.Its corresponding electrocatalytic performance towards oxygen reduction/evolution reactions(ORR and OER)was systematically investigated in alkaline electrolyte.Structural,morphological and compositional studies revealed changes in electronic and surface properties when CeO_(2)was introduced as an oxygen buffer material.The oxygen vacancies effectively enhanced the electrocatalytic activity,while the synergistic effect of co-catalyst CeO_(2),CoOx activecenters,and defective graphene with many voids facilitate the charge/mass transfer,making CoOx/CeO_(2)/RGO an efficient and stable bifunctional electrocatalyst for OER/ORR with△E=0.76 V(△E=E10mAcm.-2OER-E_(1/2).ORR).This parameter is 70 mV and 270 mV lower than CoOx/RGO and the benchmark Pt/C,respectively.In addition,the OER/ORR bifunctionality of CoOx/CeO_(2)/RGO composite outperforms that of Pt/C catalyst in a H2-O_(2)micro fuel cell platform.

关键词： Co3O4 CeO_(2) Oxygen vacancies ORR OER

Blood–brain barrier dysfunction in intensive care unit

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Journal of Intensive Medicine 2023年第4期3卷 303-312页

作者： Loic Le Guennec nicolas Weiss Département de neurologie Sorbonne UniversitéAP-HP Sorbonne UniversitéHôpital de la Pitié-SalpêtrièreUnitéde Médecine Intensive Réanimationàorientation neurologiqueParis 75013France Groupe de Recherche Clinique en REanimation et Soins intensifs du Patient en Insuffisance Respiratoire aiguE(GRC-RESPIRE)Sorbonne Université Paris 75013France Brain Liver Pitié-Salpêtrière(BLIPS)Study Group INSERM UMR_S 938Centre de recherche Saint-AntoineMaladies métaboliquesBiliaires et fibro-inflammatoire du foieInstitute of Cardiometabolism and Nutrition(ICAN)Paris 75013France

The central nervous system is characterized by a peculiar vascularization termed blood–brain barrier(BBB),which regulates the exchange of cells and molecules between the cerebral tissue and the whole body.BBB dysfunction is a life-threatening condition since its presence corresponds to a marker of severity in most diseases encountered in the intensive care unit(ICU).During critical illness,inflammatory response,cytokine release,and other phenomena activating the brain endothelium contribute to alterations in the BBB and increase its permeability to solutes,cells,nutrients,and xenobiotics.Moreover,patients in the ICU are often old,with underlying acute or chronic diseases,and overly medicated due to their critical condition;these factors could also contribute to the development of BBB dysfunction.An accurate diagnostic approach is critical for the identification of the mechanisms underlying BBB alterations,which should be rapidly managed by intensivists.Several methods were developed to investigate the BBB and assess its permeability.Nevertheless,in humans,exploration of the BBB requires the use of indirect methods.Imaging and biochemical methods can be used to study the abnormal passage of molecules through the BBB.In this review,we describe the structural and functional characteristics of the BBB,present tools and methods for probing this interface,and provide examples of the main diseases managed in the ICU that are related to BBB dysfunction.

关键词： Blood–brain barrier ICU hepatic encephalopathy Delirium Extracorporeal membrane oxygenation(ECMO) Acute bacterial meningitis

Portal vein arterialization in 25 liver transplant recipients:A Latin American single-center experience

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World Journal of Transplantation 2024年第2期14卷 135-147页

作者： nicolas Andres Cortes-Mejia Diana Fernanda Bejarano-Ramirez Juan Jose Guerra-Londono Diego Rymel Trivino-Alvarez Raquel Tabares-Mesa alonso Vera-Torres Division of Anesthesiology Critical Care Medicineand Pain MedicineThe University of Texas MD Anderson Cancer CenterHoustonTX 77030United States Transplant and Hepatobiliary Surgery Department Fundacion Santa Fe de BogotaBogota 110111Colombia General Surgery Department Fundacion Santa Fe de BogotaBogota 110111Colombia

BACKGROUND Portal vein arterialization(PVA)has been used in liver transplantation(LT)to maximize oxygen delivery when arterial circulation is compromised or has been used as an alternative reperfusion technique for complex portal vein thrombosis(PVT).The effect of PVA on portal perfusion and primary graft dysfunction(PGD)has not been assessed.All patients receiving PVA and LT at the Fundacion Santa Fe de Bogota between 2011 and 2022 were analyzed.To account for the time-sensitive effects of graft perfusion,patients were classified into two groups:prereperfusion(pre-PVA),if the arterioportal anastomosis was performed before graft revascularization,and postreperfusion(post-PVA),if PVA was performed afterward.The pre-PVA rationale contemplated poor portal hemodynamics,severe vascular steal,or PVT.Post-PVA was considered if graft hypoperfusion became evident.Conservative interventions were attempted before PVA.

关键词： Liver transplantation Portal vein arterialization Arteriovenous anastomoses Portal hypertension Portal vein thrombosis Spontaneous portosystemic shunts Vascular steal phenomenon Primary graft dysfunction Early allograft dysfunction

Slow and steady wins the race: contrasted phylogeographic signatures in two Alpine amphibians

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Integrative Zoology 2022年第1期17卷 181-190页

作者： Christophe DUFRESNES nicolas RODRIGUES Romain SAVARY LASER College of Biology and EnvironmentNanjing Forestry UniversityNanjingChina Department of Ecology&Evolution University of LausanneLausanneSwitzerland Laboratory for Biological Geochemistry School of ArchitectureCivil and Environmental EngineeringEcole Polytechnique Fédérale de Lausanne(EPFL)LausanneSwitzerland

A deeper phylogeographic structure is expected for slow-dispersing habitat specialists compared to widespread adaptable species,especially in topographically complex regions.We tested this classic assumption by comparing the genomic(RAD-sequencing)phylogeographies of 2 amphibians inhabiting the Swiss Alps:the mobile,cosmopolitan common frog(Rana temporaria)against the stationary,mountain endemic Alpine salamander(Salamandra atra).Our results ran opposite of predictions:the frog displayed significantly higher genetic divergences and lower within-population variation compared to the salamander.This implies a prominent role for their distinctive glacial histories in shaping intraspecific diversity and structure:diversification and recolonization from several circum-Alpine micro-refugia for the frog versus a single refugium for the salamander,potentially combined with better population connectivity and stability.These striking differences emphasize the great variability of phylogeographic responses to the Quaternary glaciations,hence the complexity to predict general patterns of genetic diversity at the regional scale,and the forces that underlie them.

关键词： Alps comparative phylogeography dispersal RAD-sequencing Rana temporaria Salamandra atra

Diabetes and pulmonary infection:how hyperglycaemia shapes the immune system

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1245-1246页

作者： Christian Herder Michael Roden nicolas Venteclef Institute for Clinical Diabetology German Diabetes CenterLeibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf40225DüsseldorfGermany German Center for Diabetes Research(DZD) Partner Düsseldorf85764München-NeuherbergGermany Department of Endocrinology and Diabetology Medical Faculty and University Hospital DüsseldorfHeinrich Heine University Düsseldorf40225DüsseldorfGermany Institut Necker-Enfants Malades(INEM) UniversitéParis CitéINSERM UMR-S1151CNRS UMR-S8253ParisFrance

In a recent study published in Nature,Nobs and colleagues aimed to identify novel mechanisms that may explain why diabetes is associated with an increased susceptibility to viral respiratory infections.Their analyses revealed a central role of lung dendritic cells(DC)which exhibited several functional defects induced by hyperglycaemia and consequently result in impaired antiviral immune responses.

关键词： impaired lung respiratory

The Impact of Meetings on the Network Governance and Mobility of UN Policy Programs on Environment and Education

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ECNU Review of Education 2023年第4期6卷 597-622页

作者： nicolas Stahelin Marcia McKenzie University of Saskatchewan University of Melbourne

Purpose:This paper adds to the understandings of how face-to-face meetings contribute to the network governance and global mobility of United Nations(UN)policy programs on environmental and sustainability education(ESE).Design/Approach/Methods:Data from interviews with 13 international ESE policy leaders were transcribed,coded,and analyzed for key themes related to the research purpose.Findings:The findings indicate that meetings provide an arena for collaboration and influence on UN ESE policy programs,as well as facilitating the impact of the policy programs on UN member country policy.In addition,attending meetings enables the production of network relations that bind ESE policy communities together across distant locations.They are also a venue for the networking labor involved in forging new relationships and facilitating the social learning that supports global policy mobility.Originality/Value:This pilot study enriches understanding of face-to-face meetings as a key vector of policy mobility and a significant factor in the overall network governance of UN organizations and their policy programs.We hope the study contributes to the fields of critical policy studies and ESE,as well as to informing policy actors on how important their participation in meetings can be for the network governance and mobility of UN policy programs.

关键词： Environmental education international organizations network ethnography network governance policy mobilities sustainability education

Modeling and Measuring Friction of the Leighton 10m Telescope

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Research in Astronomy and Astrophysics 2022年第12期22卷 311-321页

作者： Yongwei Guo David Woody nicolas Matinez Chinese Academy of Sciences South America Center for Astronomy Camino El Observatorio 1515Las CondesSantiagoChile National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China California Institute of Technology Owens Valley Radio ObservatoryBig PineCA 93513USA Universidad de Concepcion Facultad de Ciencias Físicas y MatematicasConcepcion403000Chile

Estimating and identifying friction are important aspects of simulating a mechanical drive system. Accurate friction modeling helps to improve a telescope's performance. However, the friction conditions inside are complex and hard to measure. We did simulations with mathematical transfer functions for the Leighton 10 m Telescope and employed a polyline model to identify sources of friction. We made a two-stage model for the Leighton 10 m Telescope. Based on measurements of the motor's currents and speeds, we constructed a curve containing the friction information of the transmission elements. We simulated the system using a step function input under many combinations of friction parameters. By comparing simulation results with the measured ones, we determined the various friction components. This model accurately reproduced the telescope performance including the nonlinearities.

关键词： astronomical instrumentation methods and techniques telescopes methods:analytical

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聚合物和新拌混凝土性能研究进展（英文）

硅酸盐学报 2015年第10期43卷 1401-1407页

作者： nicolas ROUSSEL IFSTTAR East Paris UniversityNavier Laboratory

通过对颗粒/颗粒和颗粒/液相之间相互作用进行理论和微观力学研究,首先提出了稳定状态下水泥净浆在简单剪切力作用下,以剪切速率和固体体积分数为参数的主要影响因素理论方程。在此框架下,对水泥混凝土工业中常用聚合物掺入后,胶凝材料... 详细信息

通过对颗粒/颗粒和颗粒/液相之间相互作用进行理论和微观力学研究,首先提出了稳定状态下水泥净浆在简单剪切力作用下,以剪切速率和固体体积分数为参数的主要影响因素理论方程。在此框架下,对水泥混凝土工业中常用聚合物掺入后,胶凝材料浆体基本物理性能研究的最新进展进行了阐述。最后,讨论了水泥净浆流变性能和新拌混凝土性能之间的转换关系。

关键词：流变学屈服强度黏度聚合物新拌混凝土