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Particuology 2024年第6期89卷 99-108页

作者： Weihao Liu Huanhuan He Qingtao Liu xin wan.Jianglan Shui School of Materials Science and Engineering Beihang UniversityBeijing100191China School of Space and Environment Beihang UniversityBeijing102206China Tianmushan Laboratory Hangzhou310023China

The excellent oxygen reduction reaction(ORR)activity of Fe–N–C catalysts in acidic media makes them potential for low-cost proton exchange membrane fuel *** recent years,it has been shown that heteroatoms(B,O,S,P,Cl,F,etc.)can be used as electron-withdrawing groups to modulate the planar structure and electron distribution of the Fe–Nx active sites to achieve simultaneous improvement of catalytic activity and ***,the optimal location of the heteroatoms remains ***,taking chalcogen heteroatoms(S and Se)as an example,we control the doping positions and investigate their effect on the ORR performance of the Fe–N–C *** first coordination shell of the iron single atom is identified as the optimal doping *** optimized catalysts Fe–N_(3)Se_(1)/NC and Fe–N_(3)Se_(1)/NC demonstrate improved activity and stability in both half cells and fuel *** work provides insights into the enhancement mechanism of heteroatom doping in single-atom catalysts.

关键词： Oxygen reduction reaction Fe-N-C catalysts Hetero-atom doping Doping position Enhancement mechanism

Numerical analysis of the correlation between fluid dynamic modes and hydrodynamic noise in flows around a three-dimensional circular cylinder

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Journal of Hydrodynamics 2024年第1期36卷 119-129页

作者： Jia-jia Qin Ming-xin Zou Yuan Zhuang De-cheng wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Wuhan Second Ship Design and Research Institute Wuhan430205China

The flow around a circular cylinder for Re=1000 is characterized by flow separation and Karman vortex *** typical flow features can be captured to study the correlation between fluid fields and sound *** this paper,the three-dimensional circular cylinder is taken as the research object,and the probes of surface fluctuating pressure and far field sound pressure are arranged every 10°.The directional diagram and the coherence of fluctuating pressure and sound pressure are *** relationship between the flow mode and hydrodynamic noise is studied by using dynamic mode decomposition(DMD).The characteristics of the dipole and quadrupole sound source term of a long span cylinder are *** results show that at the angles between 30°–120°and 190°–350°,the fluctuating pressure contributes more to the generation of dipole *** quadrupole sound source shows three-dimensional effects,which is more obvious in a cylinder with large spanwise length.

关键词： Pressure coherence dynamic mode decomposition flow-sound correlation circular cylinder

Identification and Molecular Characterization of the Alkaloid Biosynthesis Gene Family in Dendrobium catenatum

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Phyton-International Journal of Experimental Botany 2024年第1期93卷 81-96页

作者： Liping Yang xin wan.Runyang Zhou Yingdan Yuan College of Horticulture and Landscape Architecture Yangzhou UniversityYangzhouChina Jiangsu Academy of Forestry NanjingChina Jiangsu Yangzhou Urban Forest Ecosystem National Observation and Research Station YangzhouChina

As one of the main active components of Dendrobium catenatum, alkaloids have high medicinal value. The physicochemicalproperties, conserved domains and motifs, phylogenetic analysis, and cis-acting elements of the genefamily members in the alkaloid biosynthesis pathway of D. catenatum were analyzed by bioinformatics, and theexpression of the genes in different years and tissues was analyzed by qRT-PCR. There are 16 gene families,including 25 genes, in the D. catenatum alkaloid biosynthesis pathway. The analysis of conserved domains andmotifs showed that the types, quantities, and orders of domains and motifs were similar among members ofthe same family, but there were significant differences among families. Phylogenetic analysis indicated that thegene family members showed some evolutionary conservation. Cis-acting element analysis revealed that therewere a large number of light-responsive elements and MYB (v-myb avian myeloblastosis viral oncogene homolog)-related elements in these genes. qRT-PCR showed that expressions of gene family members involved in alkaloidsynthesis were different in different years and tissues of D. catenatum. This study provides a theoretical basisfor further exploration of the regulatory mechanisms of these genes in the alkaloid biosynthesis of D. catenatum.

关键词： Dendrobium catenatum gene family alkaloid biosynthesis

Critical role of carbon support in metal nanoaggregate facilitating Fe-N-C catalyst for PEM fuel cell application

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Journal of Energy Chemistry 2024年第10期97卷 669-676页

作者： Liming Guo xin wan.Qingtao Liu Xiaofang Liu Jiaxiang Shang Ronghai Yu Jianglan Shui School of Materials Science and Engineering Beihang University Tianmushan Laboratory

Metal nanoaggregates can simultaneously enhance the activity and stability of Fe-N-C catalysts in proton-exchange-membrane fuel cells（PEMFC）.Previous studies on the relevant mechanism have focused on the direct interaction between FeN4active sites and metal ***,the role of carbon support that hosts metal nanoaggregates and active sites has been ***,a Fe-N-C catalyst encapsulating inactive gold nanoparticles is prepared as a model catalyst to investigate the electronic tuning of Au nanoparticles（NPs） towards the carbon *** NPs donate electrons to carbon support,making it rich in π electrons,which reduces the work function and regulates the electronic configuration of the FeN4sites for an enhanced ORR ***,the electron-rich carbon support can mitigate the electron depletion of FeN4sites caused by carbon support oxidation,thereby preserving its high *** yield and accumulation of H2O2are thus alleviated,which delays the oxidation of the catalyst and benefits the *** to the electron-rich carbon support,the composite catalyst achieves a top-level peak power density of 0.74 W/cm2in a 1.5 bar H2-air PEMFC,as well as the improved *** work elucidates the key role of carbon support in the performance enhancement of the FeN-C/metal nanoaggregate composite catalysts for fuel cell application.

关键词： Carbon support Fe-N-C Fuel cells Hetero-structure catalyst Oxygen reduction reaction

Multiple pretreatments can effectively improve the functionality of mesenchymal stem cells

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World Journal of Stem Cells 2024年第2期16卷 58-63页

作者： xin-xing wan.Xi-Min Hu Kun Xiong Department of Endocrinology Third Xiangya HospitalCentral South UniversityChangsha 410013Hunan ProvinceChina Department of Dermatology Xiangya HospitalCentral South UniversityChangsha 410008Hunan ProvinceChina Department of Anatomy and Neurobiology School of Basic Medical ScienceCentral South UniversityChangsha 410013Hunan ProvinceChina

In this editorial,we offer our perspective on the groundbreaking study entitled“Hypoxia and inflammatory factor preconditioning enhances the immunosup-pressive properties of human umbilical cord mesenchymal stem cells”,recently published in World Journal of Stem *** over three decades of research on the clinical application of mesenchymal stem cells(MSCs),only a few therapeutic products have made it to clinical use,due to multiple preclinical and clinical challenges yet to be *** study proved the hypoxia and inflammatory factor preconditioning led to higher immunosuppressive effects of MSCs without damaging their biological characteristics,which revealed the combination of inflammatory factors and hypoxic preconditioning offers a promising approach to enhance the function of *** we delve deeper into the intricacies of pretreat-ment methodologies,we anticipate a transformative shift in the landscape of MSC-based therapies,ultimately contributing to improved patient outcomes and advancing the field as a whole.

关键词： Mesenchymal stem cells Inflammatory factor Hypoxia Pretreatment

Pretreatment can alleviate programmed cell death in mesenchymal stem cells

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World Journal of Stem Cells 2024年第8期16卷 773-779页

作者： xin-xing wan.Xi-Min Hu Qi Zhang Kun Xiong Department of Endocrinology Third Xiangya HospitalCentral South UniversityChangsha 410013Hunan ProvinceChina Department of Dermatology Xiangya HospitalCentral South UniversityChangsha 410008Hunan ProvinceChina Department of Anatomy and Neurobiology Central South UniversityChangsha 410000Hunan ProvinceChina Department of Anatomy and Neurobiology School of Basic Medical ScienceCentral South UniversityChangsha 410013Hunan ProvinceChina

In this editorial,we delved into the article titled“Cellular preconditioning and mesenchymal stem cell ferroptosis.”This groundbreaking study underscores a pivotal discovery:Ferroptosis,a type of programmed cell death,drastically reduces the viability of donor mesenchymal stem cells(MSCs)after engraftment,thereby undermining the therapeutic value of cell-based ***,the article proposes that by manipulating ferroptosis mechanisms through preconditioning,we can potentially enhance the survival rate and functionality of MSCs,ultimately amplifying their therapeutic *** the crucial role ferroptosis plays in shaping the therapeutic outcomes of MSCs,we deem it im-perative to further investigate the intricate interplay between programmed cell death and the therapeutic effectiveness of MSCs.

关键词： Mesenchymal stem cells Programmed cell death Apoptosis Autophagy Ferroptosis

Evolution of interfacial heat transfer,contact behavior and microstructure during sub-rapid solidification of molten steel with different hydrogen contents

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Journal of Iron and Steel Research International 2024年第1期31卷 215-223页

作者： Cheng Lu wan.lin wan. Chen-yang Zhu Jie Zeng xin-yuan Liu Hua-long Li School of Metallurgy and Environment Central South UniversityChangsha410083HunanChina National Center for International Research of Clean Metallurgy Central South UniversityChangsha410083HunanChina Institute of Research of Iron and Steel ShasteelZhangjiagang215625JiangsuChina

Typical Q235 low-carbon steel samples with different hydrogen contents(0.0004,0.0008,and 0.0013 wt.%)were prepared by adjusting the environment humidity and *** effects of hydrogen on interfacial heat transfer,contact behavior,and microstructure evolution were investigated using a novel droplet solidification *** results revealed that when the hydrogen content increases from 0.0004 to 0.0013 wt.%,the maximum heat flux between the molten steel and cooling substrate decreases from 8.01 to 6.19 MW/m^(2),and the total heat removed in the initial 2 s reduces from 10.30 to 8.27 MJ/m^(2).Moreover,the final contact angle between the molten steel and substrate increases from 103.741°to 113.697°,and the number of pores on the droplet bottom surface increases significantly from 21 to 210 with the increase in *** surface roughness of the droplet bottom surface increases from 20.902 to 49.181 *** addition,the average grain size of the droplet increases from 14.778 to 33.548 pm with the increase in the hydrogen *** interfacial contact condition becomes worse due to the escape of hydrogen from the steel matrix during the cooling process,which leads to the reduction in the interfacial heat transfer and the increase in the grain size.

关键词： Strip casting Hydrogen content Interfacial heat transfer behavior Contact behavior Microstructure evolution

Boosting thermal stability and crystallization of closed-loop-recyclable biodegradable poly(p-dioxanone) by end-group regulation

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Science China Chemistry 2024年第2期67卷 642-651页

作者： Jin Lei Zhu-xin Gui wan.Ting Xiong Gang Wu Si-Chong Chen Yu-Zhong wan. The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MoE) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)State Key Laboratory of Polymer Materials EngineeringCollege of ChemistrySichuan UniversityChengdu610064China

A chemically closed-loop-recyclable biodegradable polymer,poly(p-dioxanone)(PPDO),is one of the ideal candidates for single-use plastic products due to its suitability for different application ***,when PPDO wastes can be collected,its monomer p-dioxanone(PDO) will be obtained through chemical recycling of these wastes;when cannot be collected,the wastes are able to be biodegraded into harmless ***,unsatisfied thermal stability and low crystallization rate of PPDO restrict its wider ***,based on end-group regulation,we simultaneously realized the significant enhancement of thermal stability and crystallization of PPDO through the simple melt processing with tributyl phosphite(TBP) or triphenyl phosphite(TPP).The model reactions were conducted to investigate the reaction mechanism and theoretical products during the preparation of PPDO/phosphite *** kinds of phosphites were proved to act as the end-capped reagent and chain extender in the melt processing,while TBP presented better *** a result,the activation energy of thermal decomposition was largely elevated,and the unprecedented T_(5%)(the temperature at a weight loss of 5%) and Tmax(the temperature at a maximum rate of weight loss) of PPDO were obtained,i.e.,T_(5%)of ~330 ℃ and Tmaxof ~385 ℃ in N_(2) atmosphere,T_(5%)of ~240 ℃ and Tmaxof ~317 ℃ in air atmosphere,***,the increased crystallization rate,crystallinity,crystalline orderliness,and realizable monomer recovery(yield >90%,purity >99.9%) of PPDO/phosphite compounds were confirmed.

关键词： poly(p-dioxanone) phosphite thermal stability crystallization end-group regulation

Association of autoimmune thyroid disease with type 1 diabetes mellitus and its ultrasonic diagnosis and management

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World Journal of Diabetes 2024年第3期15卷 348-360页

作者： Jin wan. Ke wan.xin Chang Rui-Feng Mao Department of Ultrasound Medicine Nanjing Lishui People’s HospitalZhongda Hospital Lishui BranchSoutheast UniversityNanjing 211200Jiangsu ProvinceChina Faculty of Medicine and Health The University of SydneyCamperdown NSW 2050Australia School of Life Science Huaiyin Normal UniversityHuai'an 223300Jiangsu ProvinceChina

As a common hyperglycemic disease,type 1 diabetes mellitus(T1DM)is a complicated disorder that requires a lifelong insulin supply due to the immunemediated destruction of pancreaticβ*** it is an organ-specific autoimmune disorder,T1DM is often associated with multiple other autoimmune *** most prevalent concomitant autoimmune disorder occurring in T1DM is autoimmune thyroid disease(AITD),which mainly exhibits two extremes of phenotypes:hyperthyroidism[Graves'disease(GD)]and hypothyroidism[Hashimoto's thyroiditis,(HT)].However,the presence of comorbid AITD may negatively affect metabolic management in T1DM patients and thereby may increase the risk for potential diabetes-related ***,routine screening of thyroid function has been recommended when T1DM is ***,first,we summarize current knowledge regarding the etiology and pathogenesis mechanisms of both ***,an updated review of the association between T1DM and AITD is ***,we provide a relatively detailed review focusing on the application of thyroid ultrasonography in diagnosing and managing HT and GD,suggesting its critical role in the timely and accurate diagnosis of AITD in T1DM.

关键词： Type 1 diabetes mellitus Autoimmunity Autoimmune thyroid disease Ultrasonography Diagnosis

Copper Metabolism and Cuproptosis:Molecular Mechanisms and Therapeutic Perspectives in Neurodegenerative Diseases

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Current Medical Science 2024年第1期44卷 28-50页

作者： Xiao-xia BAN Hao wan.xin-xing wan.Ya-ting TAN Xi-min HU Hong-xia BAN xin-yu CHEN Kun HUANG Qi ZHANG Kun XIONG Department of Human Anatomy and Neurobiology School of Basic Medical ScienceCentral South UniversityChangsha 430013China Department of Endocrinology Third Xiangya HospitalCentral South UniversityChangsha 430013China Department of Dermatology Xiangya HospitalCentral South UniversityChangsha 430013China Affiliated Hospital Inner Mongolia Medical UniversityHohhot 010050China Key Laboratory of Emergency and Trauma of Ministry of Education Hainan Medical UniversityHaikou 571199China Hunan Key Laboratory of Ophthalmology Changsha 430013China

Copper is an essential trace element,and plays a vital role in numerous physiological processes within the human *** normal metabolism,the human body maintains copper *** deficiency or excess can adversely affect cellular ***,copper homeostasis is stringently *** studies suggest that copper can trigger a specific form of cell death,namely,cuproptosis,which is triggered by excessive levels of intracellular *** induces the aggregation of mitochondrial lipoylated proteins,and the loss of iron-sulfur cluster *** neurodegenerative diseases,the pathogenesis and progression of neurological disorders are linked to copper *** review summarizes the advances in copper homeostasis and cuproptosis in the nervous system and neurodegenerative *** offers research perspectives that provide new insights into the targeted treatment of neurodegenerative diseases based on cuproptosis.

关键词： cuproptosis copper metabolism copper homeostasis neurodegeneration neurodegenerativedisease