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Collective Molecular Machines: Multidimensionality and Reconfigurability

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Nano-Micro Letters 2024年第8期16卷 309-340页

作者： Bin wang yuan Lu Department of Chemical Engineering Tsinghua UniversityBeijing 100084People’s Republic of China Key Laboratory of Industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084People’s Republic of China

Molecular machines are key to cellular activity where they are involved in converting chemical and light energy into efficient mechanical *** the last 60 years,designing molecular structures capable of generating unidirectional mechanical motion at the nanoscale has been the topic of intense *** progress has been made,attributed to advances in various fields such as supramolecular chemistry,biology and nanotechnology,and ***,individual molecular machines are only capable of producing nanometer work and generally have only a single *** order to address these problems,collective behaviors realized by integrating several or more of these individual mechanical units in space and time have become a new *** this review,we comprehensively discuss recent developments in the collective behaviors of molecular *** particular,collective behavior is divided into two *** is the appropriate integration of molecular machines to efficiently amplify molecular motions and deformations to construct novel functional *** other is the construction of swarming modes at the supramolecular level to perform nanoscale or microscale *** discuss design strategies for both modes and focus on the modulation of features and ***,in order to address existing challenges,the idea of transferring experience gained in the field of micro/nano robotics is presented,offering prospects for future developments in the collective behavior of molecular machines.

关键词： Molecular machines Collective control Collective behaviors DNA Biomolecular motors

Global adaptive output-feedback tracking with prescribed performance for uncertain nonlinear systems

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Science China(Information Sciences) 2024年第5期67卷 150-164页

作者： yuan wang Yungang LIU School of Control Science and Engineering Shandong University

At present, one typical control strategy for guaranteeing transient and steady-state performance is funnel control and prescribed performance control. The strategy features completely discarding the system nonlinearities, even if they are completely known and available. Such an intrinsic feature requires the controller to produce a larger control effect to eliminate the negative impact caused by the high nonlinearities, leading to a conservative controller. In this paper, we fully take advantage of known information on nonlinearities in control design, instead of completely discarding it as done in funnel control. Particularly, we leverage adaptive techniques(i.e., high-gain dynamic compensation) to deal with unknown system nonlinearities. Meanwhile, we integrate the tools of output feedback, tracking control, and the performance *** such, an adaptive output-feedback scheme is developed for global tracking with spatiotemporal performance specifications: arbitrarily given tracking accuracy and accuracy-ensured time. A simulation example supports the developed approach.

关键词： uncertain nonlinear systems output feedback prescribed performance unknown control direction dynamic high gain global tracking

Simultaneously enhancing erosion and compression resistance:designing AlCoCrFeNi high-entropy alloy strengthened Ag-based contacts

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Rare Metals 2024年第9期43卷 4476-4492页

作者： Xiao-Yang Xue Zhe wang hui-Ling Nie Zhao yuan Jun wang Chang-Hu Xu Kai Wen Cong-Hao Yu School of Materials Science and Engineering Xi’an Polytechnic UniversityXi’an 710048China School of Physics Xi’an Jiaotong UniversityXi’an 710049China Key Laboratory of Pulsed Power Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Designing microstructures and unveiling dynamic erosion mechanisms remain important challenges for Ag-based *** simultaneously enhance erosion and compression resistance,an Al Co Cr Fe Ni high-entropy alloy(HEA)is introduced into Ag-based materials to fabricate novel Ag-HEA contacts with island-and skeletonrestricted *** arc erosion experimental results reveal that the skeleton-restricted HEA microstructure is the key factor in reducing the hill and crater morphologies of the contact surface,effectively delaying material transfer between the movable and stationary *** molten bridge evolution and compressive deformation behavior of Ag-HEA contacts with various microstructures are investigated using molecular dynamics(MD)*** results indicate that the constraint of Ag atom diffusion in the molten pool and the involvement of HEA atoms in the molten bridge are the primary mechanisms for improving erosion *** skeleton-restricted HEA microstructure reduces the total energy and structural stability of the molten bridge system and promotes its fracture and ***,the synergistic effect of the twin and Lomerz–Cottrell lock structures can hinder dislocation glide,generating dispersed and small-area stacking faults in the Ag matrix and mitigating the concentration of shear ***,the skeleton-restricted HEA microstructure contributes positively to compression *** study presents a novel approach to designing Ag-based contacts.

关键词： Electrical contact materials High entropy alloys Arc erosion Molecular dynamics Microstructures

Sea-level change in coastal areas of China:Status in 2021

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Advances in Climate Change Research 2024年第3期15卷 515-524页

作者： Wen-Shan LI hui wang Wen-Xi XIANG Ai-Mei wang Wei-Qing XU Yu-Xi JIANG Xin-hui WU Meng-yuan QUAN National Marine Data and Information Service Tianjin 300171China Ocean University of Chin1 Qingdao 266100China University of Michigan‒Shanghai Jiao Tong University Joint Institute Shanghai 200030China

The sea level in coastal areas of China reached the second highest in 2021,just after that recorded in *** force and dynamic analyses based on tide gauges,satellite observations,reanalysis data and regional numerical outputs were conducted to understand these abnormally high sea levels and determine their possible *** show that the coastal sea level of China had increased at an annual rate of 3.4±0.3 mm during 1980-2021,with an acceleration of 0.06±0.02 mm per *** superposition of significant oscillations of quasi-2,3-7,quasi-9,quasi-11,quasi-19 and 20-30 years contributed to the anomalously high sea *** negative-phased El Nino/Southern Oscillation was correlated with the anomalously high sea level and the north-south anti-phase pattern of the coastal sea level in ***,phase lags of 1-4 months occurred with the sea-level *** a decadal timescale,the Pacific Decadal Oscillation(PDO)was negatively correlated with the anomalous mean sea level(MSL),and the negative-phased PDO contributed to the anomalous sea-level change in ***,the monthly MSL peaked in April and July,and the contribution of wind stress to the anomalously high sea level was 38.5%in the south of the Taiwan Strait in April and 30%along the coast of China in *** results were consistent with the tide gauge and satellite *** agreement was also observed between the coastal sea-level fingerprint and the air and sea surface temperatures.

关键词： Sealevel La Nina PDO Wind stress

High-Temperature Stability of Mg-1Al-12Y Alloy Containing LPSO Phase and Mechanism of Its Portevin-Le Chatelier(PLC)Effect

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 982-998页

作者： Qian-Long Ren Shuai yuan Shi-Yu Luan Jin-hui wang Xiao-Wei Li Xiao-Yu Liu Qinghai Provincial Key Laboratory of New Light Alloys Qinghai Provincial Engineering Research Center of High Performance Light Metal Alloys and FormingQinghai UniversityXining810016China School of Materials Science and Engineering Shenyang University of TechnologyShenyang110870China

In this study,the high-temperature stability and the generation mechanism of the Portevin-Le Chatelier(PLC)effect in solid-solution Mg-1Al-12Y alloy with different heat treatment processes were investigated by adjusting the content of long-period stacking ordered(LPSO)*** was found that the content of LPSO phases in the alloys differed the most after heat treatment at 530℃for 16 h and 24 h,with values of 13.56%and 3.93%***,high-temperature tensile experiments were conducted on these two alloys at temperatures of 150℃,200℃,250℃,and 300℃.The results showed that both alloys exhibited the PLC effect at temperatures ranging from 150 to 250℃.However,at a temperature 300℃,only the alloy with a greater concentration of LPSO phases exhibited the PLC effect,whereas the alloy with a lower proportion of LPSO phases did not exhibit this ***,both alloys exhibited remarkable high-temperature stability,with the alloy containing a greater percentage of LPSO phases also demonstrating superior *** underlying mechanism for this phenomenon lies in the exceptional high-temperature stability exhibited by the second phase within the ***,the LPSO phase effectively obstructs the movement of dislocations,and it also undergoing kinking to facilitate plastic deformation of the *** results indicate that the PLC effect can be suppressed by reducing dislocation pile-up at grain boundaries,which leads to a decrease in alloy plasticity but an increase in *** presence of the PLC effect in the WA121 alloy is attributed to the abundant dispersed second phase within the alloy,which initially hinders the movement of dislocations,leading to an increase in stress,and subsequently releases the dislocations,allowing them to continue their movement and thereby reducing in stress.

关键词： Magnesium alloy Long-period stacking ordered(LPSO)phase Portevin-Le Chatelier effect High temperature

A case of aggravation of hemolytic anemia, elevated liver enzymes and low platelet count syndrome after delivery

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Chinese Medical Journal 2011年第8期124卷 1261-1263页

作者： JIANG yuan-hui wang Yong-qing wang Jing YE Rong-hua Department of Obstetrics and Gynecology Peking UniversityThird Hospital Beijing 100191 China

Background Hemolytic anemia, elevated liver enzymes and low platelet count （HELLP） syndrome is a severe obstetric complication which usually resolves in most patients after *** We report a rare case of aggravation of HELLP syndrome after *** The patient underwent the treatment for HELLP syndrome,.including glucocorticoid therapy. The symptoms of HELLP syndrome reappeared and became more severe than before the termination of pregnancy. The patient also had severe and persistent hypoproteinemia, hyponatremia and *** HELLP syndrome is an acute and critical obstetric syndrome which can have heterogeneous presentations and variable prognosis. We should be fully aware of the diverse clinical characteristics of this condition.

关键词： HELLP syndrome hypocalcemia hyponatremia hypoproteinemia

Long noncoding RNAs HAND2-AS1 ultrasound microbubbles suppress hepatocellular carcinoma progression by regulating the miR-873-5p/tissue inhibitor of matrix metalloproteinase-2 axis

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1547-1563页

作者： Qiang Zou Hao-Wen wang Xi-Liang Di yuan Li hui Gao Department of Interventional Therapy Tianjin Medical University Cancer Institute and HospitalTianjin 300060China National Clinical Research Center for Cancer Key Laboratory of Cancer Prevention and TherapyTianjin’s Clinical Research Center for CancerTianjin 300060China College of Animal Science and Technology Northeast Agricultural UniversityHarbin 150030Heilongjiang ProvinceChina Department of Hematology and Oncology Linyi People’s HospitalLinyi 251500Shandong ProvinceChina Department of Comprehensive Oncology Baotou Cancer HospitalBaotou 014030Inner Mongolia Autonomous RegionChina

BACKGROUND Increasing data indicated that long noncoding RNAs(lncRNAs)were directly or indirectly involved in the occurrence and development of tumors,including hepatocellular carcinoma(HCC).Recent studies had found that the expression of lncRNA HAND2-AS1 was downregulated in HCC tissues,but its role in HCC progression is *** targeted microbubble destruction mediated gene transfection is a new method to overexpress *** To study the role of ultrasound microbubbles(UTMBs)mediated HAND2-AS1 in the progression of HCC,in order to provide a new reference for the treatment of *** In vitro,we transfected HAND2-AS1 siRNA into HepG2 cells by UTMBs,and detected cell proliferation,apoptosis,invasion and epithelial-mesenchymal transition(EMT)by cell counting kit-8 assay,flow cytometry,Transwell invasion assay and Western blotting,*** addition,we transfected miR-837-5p mimic into UTMBs treated cells and observed the changes of cell ***,the UTMBs treated HepG2 cells were transfected together with miR-837-5p mimic and tissue inhibitor of matrix metalloproteinase-2(TIMP2)overexpression vector,and we detected cell proliferation,apoptosis,invasion and *** vivo,we established a mouse model of subcutaneous transplantation of HepG2 cells and observed the effect of HAND2-AS1 silencing on tumor formation *** We found that UTMBs carrying HAND2-AS1 restricted cell proliferation,invasion,and EMT,encouraged apoptosis,and HAND2-AS1 silencing eliminated the effect of ***,miR-873-5p targets the gene HAND2-AS1,which also targets the 3’UTR of *** miR-873-5p mimic counteracted the impact of ***,miR-873-5p mimic solely or in combination with pcDNA-TIMP2 had been transformed into HepG2 cells exposed to *** discovered that TIMP2 reversed the effect of miR-873-5p mimic caused by the blocked signalling cascade for matrix metalloproteinase(MMP)2/*** vivo results showed that HAND2-AS1 silencing sig

关键词： Hepatocellular carcinoma Ultrasound microbubbles Long noncoding RNA HAND2-AS1 miR-873-5p Tissue inhibitor of matrix metalloproteinase-2

Single-atom Ag-loaded carbon nitride photocatalysts for efficient degradation of acetaminophen:The role of Ag-atom and O_(2)

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Journal of Environmental Sciences 2024年第5期139卷 12-22页

作者： Yi yuan Wen-Long wang Zhi-Wei wang Jin wang Qian-yuan Wu Key Laboratory of Microorganism Application and Risk Control of Shenzhen Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental SafetyInstitute of Environment and EcologyShenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Shenzhen Environmental Science and New Energy Technology Engineering Laboratory Tsinghua-Berkeley Shenzhen InstituteShenzhen 518055China College of Materials Science and Engineering Shenzhen UniversityShenzhen 518071China

Carbon nitride has been extensively used as a visible-light photocatalyst,but it has the disadvantages of a low specific surface area,rapid electron-hole recombination,and relatively low light *** this study,single-atom Ag was successfully anchored on ultrathin carbon nitride(UTCN)via thermal polymerization,the catalyst obtained is called *** Ag hardly changed the carbon nitride's layered and porous physical *** exhibited efficient visible-light photocatalytic performances in the degradation of various recalcitrant pollutants,eliminations of 85% were achieved by visible-light irradiation for *** with Ag improved the photocatalytic performance of UTCN by narrowing the forbidden band gap from 2.49 to 2.36 e V and suppressing electron-hole pair *** addition,Ag doping facilitated O_(2) adsorption on UTCN by decreasing the adsorption energy from -0.2 to -2.22 e V and favored the formation of O_(2)^(·-).Electron spin resonance and radical-quenching experiments showed that O_(2)^(·-)was the major reactive species in the degradation of Acetaminophen(paracetamol,APAP).

关键词： Ag single atom Carbon nitride Photocatalysis Visible light Adsorption energy Reactive species

Toward Artificial Peptide Nanocapsules

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Nano-Micro Letters 2024年第10期16卷 240-243页

作者： yuan wang Bing Chen Laboratory for Biomaterials and Drug Delivery Department of AnesthesiologyDivision of Critical Care MedicineBoston Children's HospitalHarvard Medical SchoolBostonMA 02115USA College of Electronic and Optical Engineering and College of Flexible Electronics(Future Technology) Nanjing University of Posts and TelecommunicationsNanjing 210023People's Republic of China

HIGHLIGHTS The formation of peptide nanocapsules is facilitated by a gradient interface,where the differential solvent concentration drives the peptides to preferentially localize and *** peptide nanocapsules,characterized by their hollow structures,demonstrated potential as carriers for targeted drug delivery.1 Introduction Peptide nanocapsules are a type of nanoscale delivery system that encapsulates active substances within a shell composed of peptides,leveraging the unique properties of peptides such as biocompatibility and biodegradability[1].Historically,the development of peptide nanocapsules was inspired primordially by the natural biological processes.

关键词： Peptide nanocapsules Self-assembly Drug delivery Nanomedicine