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Vanadium-dependent activation of glucose transport in adipocytes by catecholamines is not mediated via adrenoceptor stimulation or monoamine oxidase activity

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World Journal of Diabetes 2020年第12期11卷 622-643页

作者： Jessica Fontaine Geneviève Tavernier Nathalie Morin Christian Carpéné Institut des Maladies Métaboliques et Cardiovasculaires Institut National de la Santéet de la Recherche MédicaleINSERM UMR1048UniversitéPaul Sabatier Toulouse IIIToulouse 31432France INSERM UMR 1139 Facultéde Pharmacie Universitéde ParisParis 75006France

BACKGROUND Benzylamine and methylamine activate glucose uptake in *** tyramine,this effect has even been extended to *** To investigate the effects of catecholamines and other amines on glucose *** A screening compared 25 biogenic amines on 2-deoxyglucose(2-DG)uptake activation in rat *** approaches and transgenic mouse models were then used to decipher the mode of action of several *** In rat adipocytes,insulin stimulation of 2-DG uptake was reproduced with catecholamines.100μmol/L or 1 mmol/L adrenaline,noradrenaline,dopamine and deoxyepinephrine,maximally activated hexose transport only when sodium orthovanadate was added at 100μmol/*** activation was similar to that already reported for benzylamine,methylamine and tyramine,well-recognized substrates of semicarbazide-sensitive amine oxidase(SSAO)and monoamine oxidase(MAO).Several,but not all,tested agonists ofβ-adrenoreceptors(β-ARs)also activated glucose transport whileα-AR agonists were *** of blockade byα-andβ-AR antagonists indicated that catecholamine-induced 2-DG uptake was not mediated by AR *** from mice lackingβ1-,β2-andβ3-ARs(triple KO)also responded to millimolar doses of adrenaline or noradrenaline by activating hexose transport in the presence of 100μmol/L *** MAO blocker pargyline,and SSAO inhibitors did not block the effects of adrenaline or noradrenaline plus vanadate,which were blunted by *** Catecholamines exert unexpected insulin-like actions in adipocytes when combined with *** limiting insulin resistance by activating glucose consumption at least in fat stores,we propose that catecholamine derivatives combined with vanadium can generate novel complexes that may have low toxicity and promising anti-diabetic properties.

关键词： Adipocyte Amine oxidases Insulin Diabetes Vanadium Obesity

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近30年京津冀地区湖泊面积的变化

北京大学学报（自然科学版） 2020年第2期56卷 324-330页

作者：张恒陶胜利唐志尧方精云北京大学城市与环境学院生态学系北京100871 Laboratoire Evolution et DiversitéBiologique(EDB) UniversitéToulouseⅢ-Paul SabatierToulouse 31013

利用遥感、气候和社会经济统计数据,探究1987-2017年间京津冀地区湖泊面积的变化及其与自然和社会因素的关系。结果表明,该地区湖泊面积过去30年间整体上呈减少趋势,每年减少约2%,这是自然和人为因素双重影响的结果。可分为3个阶段:前10... 详细信息

利用遥感、气候和社会经济统计数据,探究1987-2017年间京津冀地区湖泊面积的变化及其与自然和社会因素的关系。结果表明,该地区湖泊面积过去30年间整体上呈减少趋势,每年减少约2%,这是自然和人为因素双重影响的结果。可分为3个阶段:前10年(1987-1996年),湖泊面积增加约4.8×10~2 km^2 (约占76%),由自然因素主导(R^2=0.849,p=0.001);1997-2009年的13年间,湖泊面积呈减少趋势(减少约4.7×102km^2,占43%),主要由人为因素主导(R^2=0.536,p=0.013);最近8年(2010-2017年)中,湖泊面积呈增加趋势(增加约2.3×10~2 km^2,占36%),也主要由人为因素导致。虽然最近8年来该地区湖泊面积减少的趋势得到扭转,但地表水资源供需矛盾仍然严峻。

关键词：京津冀地区湖泊面积变化归一化水体指数相对水体面积变化率

Determination of Lead in Water by Linear Sweep Anodic Stripping Voltammetry (LSASV) at Unmodified Carbon Paste Electrode: Optimization of Operating Parameters

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American Journal of Analytical Chemistry 2018年第3期9卷 171-186页

作者： Ndoye Mouhamed Kane Cheikhou Gadji Elhadji Momar Rokhy Diédhiou Moussa Bagha Mar-Diop Codou Guèye Theo Tzedakis Ecole Supérieure Polytechnique Université Cheikh Anta Diop Dakar Senegal Laboratoire de Génie Chimique UMR CNRS 5503 Université de Toulouse III-Paul Sabatier Toulouse France

This study presents the elaboration of a simple and cheap electrode made by carbon paste introduced into a cavity of electrode body, and used for the lead traces determination in tap water. A potentiostatic pre-electrolysis at constant voltage enables the reduction of the lead (Pb2+) and the accumulation of the metallic lead at and into the carbon paste;the reoxidation of the Pb (Linear sweep voltammetry) leads to the anodic striping peak. The effect of the main operating parameters on the shape of the peak and the magnitude of the current was examined and their optimal values were determined. Then calibration was achieved and the method was successfully applied (using all the optimized parameters) to the determination of lead in water, with a detection limit of 0.138 μg·L-1. Compared to other methods (ICP-AES for example), the proposed method offers a satisfactory detection limit of the Pb2+ (0.138 μg·L-1) because of the important specific area of the carbon paste electrode, for a significantly lower cost. Besides, there is no observed loss in the electrode answer in terms of peak current, which means that there is no any irreversible steps nor deactivation of the electrode, even after ten successive measurements;only reduction of the lead followed by the deposit oxidation was observed at the electrode.

关键词： Carbon Paste Electrode Lead Linear Sweep Anodic Stripping Voltammetry Water

In situ electron holography of the dynamic magnetic field emanating from a hard-disk drive writer

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Nano Research 2015年第4期8卷 1241-1249页

作者： Joshua F. Einsle Christophe Gatel Aurelien Masseboeuf Robin Cours Muhammad A. Bashir Mark Gubbins Robert M. Bowman Etienne Snoeck Centre for Nanostructured Media School of Mathematics and Physics Queen's University Belfast Belfast BT7 1NN UK CEMES-cnrs 29 rueJ. Marvig 31055 Toulouse France universite de toulouse paul sabatier 118 route de Narbonne 31062 Toulouse Cedex 9 France Seagate Technology I Disc Drive Springtown Industrial Estate Derry City Co. BT48 OBF Londonderry UK

The proliferation of mobile devices in society accessing data via the ＂cloud＂ is imposing a dramatic increase in the amount of information to be stored on hard disk drives （HDD） used in servers. Forecasts are that areal densities will need to increase by as much as 35% compound per annum and by 2,020 cloud storage capacity will be around 7 zettabytes corresponding to areal densities of 2 Tb/in^2. This requires increased performance from the magnetic pole of the electromag- netic writer in the read/write head in the HDD. Current state-of-art writing is undertaken by morphologically complex magnetic pole of sub 100 nm dimensions, in an environment of engineered magnetic shields and it needs to deliver strong directional magnetic field to areas on the recording media around 50 nm × 13 nm. This points to the need for a method to perform direct quantitative measurements of the magnetic field generated by the write pole at the nanometer scale. Here we report on the complete in situ quantitative mapping of the magnetic field generated by a functioning write pole in operation using electron holography. The results point the way towards a new nanoscale magnetic field source to further develop in situ transmission electron microscopy.

关键词： electron transmissionmicroscopy off-axis electronholography in situ magnetic field magnetic recording hard disk write pole

Effects of an ultra-high magnetic field up to 25 T on the phase transformations of undercooled Co-B eutectic alloy

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Journal of Materials Science & Technology 2021年第34期93卷 79-88页

作者： Yixuan He Yuhao Wua Fan Bu Chengxiong Zou Zhangchi Bian Qiliang Huang Tie Liu Qiang Wang Jun Wang Jinshan Li Eric Beaugnon State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an.710072China Center of Advanced Lubrication and Seal Materials Northwestern Polytechnical University.Xi'an710072China Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern University.Shenyang110819China Univ.Grenoble Alpes INSA ToulouseUniv.Toulouse Paul SabatierEMFLCNRSLNCMIGrenoble38000France

While there have been multiple recent reports in the literature focusing on the effects of magnetic field on the phase transformation behaviors,the research conducted with an ultra-high magnetic field greater than 20 T is still *** the current study,the structure evolution of Co-B alloys are experimentally studied with *** effects of a 25 T magnetic field on the solidification behavior and the subsequent solid-state phase transformation behavior have been *** 25 T magnetic field is confirmed to have little effect on the homogeneous nucleation,but have some influence on the heterogeneous nucleation of Co_(3) B and Co_(23)B6 phases by modifying the wetting angleθ.The decomposition of Co_(23)B6 phase in the subsequent cooling process can be effectively suppressed by applying the 25 T magnetic *** present work might be helpful for not only theoretically understanding the influence of ultra-high magnetic field on the phase transformation behaviors but a potential technology of field-manipulation of magnetic materials.

关键词： Ultra-high magnetic field Non-equilibrium solidification Solid-state phase transformation Metastable phase

Magnetic field intensity dependent microstructure evolution and recrystallization behavior in a Co-B eutectic alloy

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Journal of Materials Science & Technology 2023年第7期138卷 93-107页

作者： Fan Bu Yiyuan Zhang Haoxiang Liu Jun Wang Eric Beaugnon Jinshan Li Yixuan He State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Center of Advanced Lubrication and Seal Materials Northwestern Polytechnical UniversityXi’an 710072China Collaborative Innovation Center of NPU Shanghai 201108China Institute of Superconducting Materials and Applied Technology Northwestern Polytechnical UniversityXi’an 710072China Univ.Grenoble Alpes INSA ToulouseUniversity Toulouse Paul SabatierEMFLCNRSLNCMIGrenoble 38000France

Systematic understanding on the magnetic field intensity dependent microstructure evolution and re-crystallization behavior in a Co-B eutectic alloy under a constant undercooling(ΔT≈100 K)were carried *** of the magnetic field,the comparable size of divorced FCC-Co and Co_(3)B eutectic ellipsoidal grains coexist with a few regular *** the magnetic field is less than 15 T,the elongated primary FCC-Co dendrites parallel to the magnetic field with the dispersed FCC-Co nano-particles em-bedded within the Co_(3)B matrix occupy the inter-dendrite *** the magnetic field increases to 20 T,the FCC-Co/Co_(2)B anomalous eutectic colonies *** formation mechanism of Co_(2)B phase is discussed from several aspects of the competitive nucleation,the chemical redistribution induced by the thermomagnetic-induced convection and magnetic dipole interaction,and the strain-induced ***,the application of magnetic field is found to promote recrystallization,proved by the lower density of misorientation,the appearance of FCC-Co annealed twins and more Co_(3)B *** work could further enrich our knowledge about the magnetic-dependent microstructure evolution and recrystallization process in the undercooled Co-B system and provide guidance for controlling the microstructures and properties under extreme conditions.

关键词： Magnetic field Undercooled solidification Microstructure evolution Recrystallization Co-B alloy

Liquid state dependent solidification of a Co-B eutectic alloy under a high magnetic field

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Journal of Materials Science & Technology 2022年第21期116卷 58-71页

作者： Yixuan He Fan Bu Yuhao Wu Jianbao Zhang Dawei Luo Zhangchi Bian Qing Zhou Tie Liu Qiang Wang Jun Wang Haifeng Wang Jinshan Li Eric Beaugnon State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Center of Advanced Lubrication and Seal Materials Northwestern Polytechnical UniversityXi’an 710072China Collaborative Innovation Center of NPU Shanghai 201108China Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang 110819China Univ.Grenoble Alpes INSA ToulouseUniv.Toulouse Paul SabatierEMFLCNRSLNCMI38000 GrenobleFrance

The structure transition inside the Co-81.5at.%B alloy liquid has been studied by an in-situ magnetization measurement.A crossover was observed on the 1/M-T curve during the overheating process,indicating that a liquid-liquid structure transition(LLST)took place in the *** on this information,the effects of LLST on the solidification behavior,microstructure and tribology property were investigated *** sample solidified with the LLST exhibits significantly different solidification behaviors,i.e.,the nucleation undercooling and the recalescence extent are conspicuously enlarged,and the solidification time is *** a result,the microstructure is effectively refined and homogenized,and the hardness and wear resistance are significantly *** present work might be helpful for not only theoretically understanding the influence of LLST on the solidification behavior but also providing an alternative approach to tailor the microstructure and properties.

关键词： Liquid-liquid structure transition Solidification Magnetization Tribology property

Chronic neuroprotective effects of low concentration lithium on SH-SY5Y cells:possible involvement of stress proteins and gene expression

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Neural Regeneration Research 2014年第7期9卷 735-740页

作者： Riadh Nciri Ezzeddine Bourogaa Samira Jbahi Mohamed Salah Allagui Abdelfattah Elfeki Christian Vincent Franoise Croute Cellular Biology Laboratory Purpan Medicine Faculty Paul Sabatier University Ecophysiology Laboratory Sciences Faculty of Sfax

To investigate the molecular mechanism underlying the neuroprotective effect of lithium on cells, in this study, we exposed SH-SY5Y cells to 0.5 mmol/L lithium carbonate （Li2CO2） for 25-50 weeks and then detected the expression levels of some neurobiology related genes and post-translational modifications of stress proteins in SH-SYSY cells, cDNA arrays showed that pyruvate kinase 2 （PKM2） and calmodulin 3 （CaM 3） expression levels were significantly down-regulated, phosphatase protein PP2A expression was lightly down-regulated, and casein kinase II （CK2）, threonine/tyrosine phosphatase 7 （PYST2）, and dopamine beta-hydroxylase （DBH） expression levels were significantly up-regulated. Besides, western blot analysis of stress proteins （HSP27, HSP70, GRP78 and GRP94） showed an over-expression of two proteins： a 105 kDa protein which is a hyper-phosphorylated isoform of GRP94, and a 108 kDa protein which is a phosphorylated tetramer of HSP27. These results suggest that the neuroprotective effects of lithium are likely related to gene expressions and post-translational modifications of proteins cited above.

关键词： lithium neuroprotection kinase phosphatase stress proteins SH-SY5Y cells geneexpression mechanism of action

Coupling Agent Based Simulation with Dynamic Networks Analysis to Study the Emergence of Mutual Knowledge as a Percolation Phenomenon

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Journal of Systems Science & Complexity 2016年第5期29卷 1358-1381页

作者： DUGDALE Julie BELLAMINE BEN SAOUD Narjes ZOUAI Fedia PAVARD Bernard universite Grenoble Alpes LIG Grenoble France university of Agder Norway universite de La Manouba Ecole Nationale des Sciences de l'Informatique Laboratoire RIADI Tunisia universite P. sabatier CNRS IRIT Toulouse France

The emergence of mutual knowledge is a major cognitive mechanism for the robustness of complex socio-technical systems. It has been extensively studied from an ethnomethodological point of view and empirically reproduced by multi-agent simulations. Whilst such simulations have been used to design real work settings the underlying theoretical grounding for the process is vague. The aim of this paper is to investigate whether the emergence of mutual knowledge(MK) in a group of colocated individuals can be explained as a percolation phenomenon. The followed methodology consists in coupling agent-based simulation with dynamic networks analysis to study information propagation phenomena: After using an agent-based simulation the authors generated and then analyzed its traces as networks where agents met and exchanged knowledge. Deep analysis of the resulting networks clearly shows that the emergence of MK is comparable to a percolation process. The authors specifically focus on how changes at the microscopic level in the proposed agent based simulator affect percolation and robustness. These results therefore provide theoretical basis for the analysis of social organizations.

关键词： Agent-based simulation complex network dynamics emergence mutual knowledge per-colation social networks.