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High-order time-reversal symmetry breaking normal state

Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 136-148页

作者： meng Zeng Lun-hui Hu Hong-Ye Hu Yi-Zhuang You Congjun Wu Department of Physics University of CaliforniaSan DiegoCalifornia 92093USA Department of Physics Zhejiang UniversityHangzhou 310058China New Cornerstone Science Laboratory Department of PhysicsSchoolof ScienceWestlake UniversityHangzhou 30024China Institute for Theoretical Sciences Westlake UniversityHangzhou 310024China Key Laboratory for Quantum Materials of Zhejiang Province School of ScienceWestlake UniversityHangzhou 310024China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China

Spontaneous time-reversal symmetry breaking plays an important role in studying strongly correlated unconventional *** two superconducting gap functions with different symmetries compete,the relative phase channel(θ_(-)≡θ_(1)-θ_(2))exhibits an Ising-type Z_(2) symmetry due to the second order Josephson coupling,where θ_(1,2) are the phases of two gap *** contrast,the U(1) symmetry in the channel of θ_(+)≡(θ_(1)+θ_(2))/2 is *** phase locking,i.e.,ordering of θ_(-),can take place in the phase fluctuation regime before the onset of superconductivity,i.e.,when θ_(+) is *** θ_(-) is pinned at ±π/2,then timereversal symmetry is broken in the normal state,otherwise,if θ_(-)=0,or,π,rotational symmetry is broken,leading to a nematic normal *** both cases,the order parameters possess a 4-fermion structure beyond the scope of mean-field theory,which can be viewed as a high order symmetry *** employ an effective two-component XY-model assisted by a renormalization group analysis to address this *** a natural by-product,we also find the other interesting intermediate phase corresponds to ordering of θ_+ but with θ_(-)*** is the quartetting,or,charge-4e,superconductivity,which occurs above the low temperature Z_(2)-breaking charge-2e superconducting *** results provide useful guidance for studying novel symmetry breaking phases in strongly correlated superconductors.

关键词： superconductivity strong correlation time-reversal breaking charge-4e

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Highly Red Emissive Conjugated Homopolymers Based on Double B←N Bridged Bipyridine Unit

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Chinese Journal of Polymer Science 2024年第8期42卷 1029-1037页

作者： Yu-Yue Gao Kai-Yuan Zhang Shu-meng Wang hui Tong Jun Liu State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Conjugated homopolymers based on six-member rings,e.g.,polyfluorene,always exhibit blue emission and conjugated homopolymers based on five-member rings,e.g.,polythiophene,can give red emission with low *** this work,we report a series of new conjugated homopolymers based on six-member rings with high-efficiency deep-red *** repeating units of the red light emitting homopolymers are double B←N bridged bipyridine(BNBP)with the boron atoms functionalized with diphenyl,borafluorene,and 2,7-di-tert-butyl-borafluorene groups,*** relationship between the chemical structures and the opto-electronic properties of the monomers and the homopolymers has been systematically *** three polymers emit pure red light(λ_(max)=656 nm)or deep red light(λ_(max)=693 nm)with fluorescence quantum efficiency in solution higher than 60%.The polymers can be used as the emitters in solution-processed organic light-emitting diodes with red emission and decent device *** work indicates a new strategy to design highly efficient light emitting conjugated polymers.

关键词： Conjugated homopolymers Double B←N bridged bipyridine(BNBP) Deep-red emission High fluorescent efficiency

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Effect of Mn addition on microstructure and mechanical properties of GX40CrNiSi25-12 austenitic heat resistant steel

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China Foundry 2024年第3期21卷 205-212页

作者： Guan-yu Jiang meng-wu Wu Xiao-guang Yang hui Wang Yu-yuan Zhu Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei Longzhong Laboratory Xiangyang 441000HubeiChina Wescast Industries(China)Co. Ltd.Wuhan 430100China

Three types of steels were designed on the basis of GX40CrNiSi25-12 austenitic heat resistant steel by adding different Mn contents(2wt.%,6wt.%,and 12wt.%).Thermodynamic calculation,microstructure characterization and mechanical property tests were conducted to investigate the effect of Mn addition on the microstructure and mechanical properties of the austenitic heat resistant *** show that the matrix structure in all the three types of steels at room temperature is completely *** NbC and M_(23)C_(6)precipitate at grain boundaries of austenite *** the increase of Mn content,the number of carbides increases and their distribution becomes more *** the Mn content increases from 1.99%to 12.06%,the ultimate tensile strength,yield strength and elongation increase by 14.6%,8.0%and 46.3%,*** improvement of the mechanical properties of austenitic steels can be explained by utilizing classic theories of alloy strengthening,including solid solution strengthening,precipitation strengthening,and grain *** increase in alloy strength can be attributed to solid solution strengthening and precipitation strengthening caused by the addition of *** improvement of the plasticity of austenitic steels can be explained from two aspects:grain refinement and homogenization of precipitated phases.

关键词： austenitic heat resistant steel manganese microstructure mechanical properties

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Effect of Active–Passive Deformation on the Thrust by the Pectoral Fins of Bionic Manta Robot

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Journal of Bionic Engineering 2024年第2期21卷 718-728页

作者： Yang Lu Shaomin meng Cheng Xing Yiwei Hao yonghui Cao Guang Pan yong Cao School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an710072China Unmanned Vehicle Innovation Center Ningbo Institute of NPUNingbo315103China State Key Lab of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou310027China Zhejiang Key Laboratory of Advanced Manufacturing Technology School of Mechanical EngineeringZhejiang UniversityHangzhou310027China

Bionic manta underwater vehicles will play an essential role in future oceans and can perform tasks,such as long-duration reconnaissance and exploration,due to their efficient *** manta wings’deformation is evident during the swimming *** improve the propulsion performance of the unmanned submersible,the study of the deformation into the bionic pectoral fin is *** this research,we designed and fabricated a flexible bionic pectoral fin,which is based on the Fin Ray®effect with active and passive deformation(APD)*** APD fin was actively controlled by two servo motors and could be passively deformed to variable *** APD fin was moved at 0.5 Hz beat frequency,and the propulsive performance was experimentally verified of the bionic pectoral fins equipped with different extents of *** results showed that the pectoral fin with active–passive deformed capabilities could achieve similar natural biological deformation in the wingspan *** average thrust(T)under the optimal wingspan deformation is 61.5%higher than the traditional passive deformed pectoral *** obtained results shed light on the design and optimization of the bionic pectoral fins to improve the propulsive performance of unmanned underwater vehicles(UUV).

关键词： Manta ray Bionic pectoral fin Fin Ray®effect Active-passive deformation(APD)

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SIRT1 inhibits apoptosis of human lens epithelial cells through suppressing endoplasmic reticulum stress in vitro and in vivo

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1205-1216页

作者： hui Cui Di Sun Sheng meng Tian-Ju Ma Zi Ye Zhao-hui Li Medical School of Chinese PLA Beijing 100089China Senior Department of Ophthalmology the Third Medical Center of PLA General HospitalBeijing 100853China

AIM:To explore the effect of silent information regulator factor 2-related enzyme 1(SIRT1)on modulating apoptosis of human lens epithelial cells(HLECs)and alleviating lens opacification of rats through suppressing endoplasmic reticulum(ER)***:HLECs(SRA01/04)were treated with varying concentrations of tunicamycin(TM)for 24h,and the expression of SIRT1 and C/EBP homologous protein(CHOP)was assessed using real-time quantitative polymerase chain reaction(RT-PCR),Western blotting,and *** morphology and proliferation was evaluated using an inverted microscope and cell counting kit-8(CCK-8)assay,*** the SRA01/04 cell apoptosis model,which underwent siRNA transfection for SIRT1 knockdown and SRT1720 treatment for its activation,the expression levels of SIRT1,CHOP,glucose regulated protein 78(GRP78),and activating transcription factor 4(ATF4)were *** potential reversal of SIRT1 knockdown effects by 4-phenyl butyric acid(4-PBA;an ER stress inhibitor)was *** vivo,age-related cataract(ARC)rat models were induced by sodium selenite injection,and the protective role of SIRT1,activated by SRT1720 intraperitoneal injections,was evaluated through morphology observation,hematoxylin and eosin(H&E)staining,Western blotting,and ***:SIRT1 expression was downregulated in TMinduced SRA01/04 ***,in SRA01/04 cells,both cell apoptosis and CHOP expression increased with the rising doses of *** stress was stimulated by TM,as evidenced by the increased GRP78 and ATF4 in the SRA01/04 cell apoptosis *** of SIRT1 by siRNA knockdown increased ER stress activation,whereas SRT1720 treatment had opposite results.4-PBA partly reverse the adverse effect of SIRT1 knockdown on *** vivo,SRT1720 attenuated the lens opacification and weakened the ER stress activation in ARC rat ***:SIRT1 plays a protective role against TM-induced apoptosis in HLECs and slows the progression of cataract in

关键词： silent information regulator factor 2-related enzyme 1 endoplasmic reticulum stress apoptosis human lens epithelial cells cataract

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Particle size characterization and sources of sediments in the Uzhumqin sand dunes

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Journal of Mountain Science 2024年第8期21卷 2631-2645页

作者： ZHANG Hao LIU Yang DANG Xiaohong meng Zhongju LI Shuangli GAO yong Inner Mongolia Agricultural University Inner Mongolia 010018China Inner Mongolia Autonomous Region Water Resources Research Institute Hohhot 010020China

Sediment constitutes the fundamental basis for forming and evolving aeolian *** characteristics of sediment particle size offer insights into the development and evolution of sandy terrain,making their study critical to understanding aeolian geomorphology and sand *** this study,we combined high-density collection of surface sediments in the Uzhumqin sand dunes and GIS spatial analysis to analyze the particle size parameters and changes in the spatial distribution of surface sediments in this *** addition,we used an end-member analysis to identify the potential sources of the *** results showed that surface sediments in the Uzhumqin sand dunes had distinct spatial *** and coarse grain sands dominated the sediments in the dunes,and the mean grain size and the sorting coefficient generally increased along the prevailing wind direction,with high values in individual areas related to factors such as material sources and vegetation *** was strongly influenced by factors such as landform change and human activity,and spatial variability became more *** and the soil fractal dimension showed generally decreasing trends along the prevailing wind *** dune fixation,the contents of clay and powder particles in the soil increased;the mean particle size,the sorting coefficient,and the fractal dimension of the soil gradually increased,and the skewness and kurtosis gradually *** end-member analysis results indicated the existence of five end-members(EM)in the dune *** 1 was a mixed component of wind-deposited fine sands and nearby fluvial *** 2 was the main component of sediments in the study area and was the result of sorting lake sediments by wind action and by the local *** 3 may be a product of river flood *** 4 and EM 5 had coarser grain *** 4 was a lake-phase sediment product influenced by topographic and vegetation cover factors,and EM

关键词： Sediment Particle size Spatial differences End-member analysis Uzhumqin sand dunes

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Safety,immunogenicity and protective effect of sequential vaccination with inactivated and recombinant protein COVID-19 vaccine in the elderly:a prospective longitudinal study

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Signal Transduction and Targeted Therapy 2024年第6期9卷 2738-2747页

作者： Hong-Hong Liu Yunbo Xie Bao-Peng Yang Huan-Yue Wen Peng-hui Yang Jin-E Lu Yan Liu Xi Chen meng-meng Qu Yang Zhang Wei-Guo Hong yong-Gang Li Junliang Fu Fu-Sheng Wang Out-patient Department of Day Diagnosis and Treatment The Fifth Medical Center of Chinese PLA General HospitalBeijing 100039China Senior Department of Infectious Diseases The Fifth Medical Center of Chinese PLA General HospitalNational Clinical Research Center for Infectious DiseasesBeijing 100039China Chinese PLA Medical School Chinese PLA General HospitalBeijing 100039China Hunyuan County People’s Hospital Datong 037499 Shanxi ProvinceChina Faculty of Hepato-Pancreato-Biliary Surgery Institute of Hepatobiliary SurgeryThe First Medical CenterChinese PLA General HospitalBeijing 100853China

The safety and efficacy of COVID-19 vaccines in the elderly,a high-risk group for severe COVID-19 infection,have not been fully *** clarify these issues,this prospective study followed up 157 elderly and 73 young participants for 16 months and compared the safety,immunogenicity,and efficacy of two doses of the inactivated vaccine BBIBP-CorV followed by a booster dose of the recombinant protein vaccine *** results showed that this vaccination protocol was safe and tolerable in the *** administering two doses of the BBIBP-CorV,the positivity rates and titers of neutralizing and anti-RBD antibodies in the elderly were significantly lower than those in the young *** the ZF2001 booster dose,the antibody-positive rates in the elderly were comparable to those in the young;however,the antibody titers remained ***,age,and underlying diseases were independently associated with vaccine immunogenicity in elderly *** pseudovirus neutralization assay showed that,compared with those after receiving two doses of BBIBP-CorV priming,some participants obtained immunological protection against BA.5 and BF.7 after receiving the ZF2001 *** infection symptoms last longer in the infected elderly and pre-infection antibody titers were negatively associated with the severity of post-infection *** antibody levels in the elderly increased significantly after breakthrough infection but were still lower than those in the *** data suggest that multiple booster vaccinations at short intervals to maintain high antibody levels may be an effective strategy for protecting the elderly against COVID-19.

关键词： vaccination vaccine doses

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Effect of annealing temperature on magnetic properties of a sintered Nd-Fe-B magnet after grain boundary diffusion with Dy_(70)Cu_(30) alloy

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Journal of Rare Earths 2024年第1期42卷 116-120,I0004页

作者： Ruipeng Qian Yuxuan Ma Fugang Chen hui Sun yong Zhao Yunlong Chen School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang212003China School of Energy and Power Engineering Jiangsu University of Science and TechnologyZhenjiang212003China

Grain boundary diffusion process(GBDP)has been developed as an effective approach to increase the coercivity of sintered Nd-Fe-B magnets by regulating the compositions and phase distributions near grain *** work aims to explore how to select the optimum annealing temperature after *** this work GBDP was performed on a sintered Nd-Fe-B magnet using Dy_(70)Cu_(30) *** GBDP the low eutectic temperature of the grain boundary phases decreases from the initial 492 to 451℃.The magnetic property dependent on different annealing temperatures near the low eutectic temperature was *** magnetic properties,especially the squareness factor of demagnetization curve show a strong dependence on the annealing *** GBDP the optimal magnetic properties can be obtained after annealing just above the low eutectic temperature of the grain boundary *** mechanism is discussed based on the microstructure analysis.

关键词： Nd-Fe-B magnet Grain boundary diffusion Annealing Dy_(70)Cu_(30)alloy Rare earths

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Interfacial friction effects on sealing performances of elastomer packer

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Petroleum Science 2024年第3期21卷 2037-2047页

作者： Peng-Cheng Wang Ming-hui Chen Jim Jenkinson yong-Xin Song Li Sun Department of Mechanical Engineering University of HoustonHoustonTX77024USA Guren Nanomaterials Suzhou215127JiangsuChina Department of Marine Engineering Dalian Maritime UniversityDalian116026LiaoningChina

Elastomer sealing performance is of critical importance for downhole tools application including the use of fracturing(Frac)plugs during multi-stage hydraulic *** practice sealing performances of such plugs are normally evaluated through pressure tests,and in numerical simulation studies,maximum contact stress,average contact stress and contact length data are used to determine sealing quality between a packer and *** previous studies,the impact of friction forces on sealing performance is often *** work aims to fill this knowledge gap in determining the influence of friction forces on elastomer packer sealing *** first determined the most appropriate constitutive hyperelastic model for the elastomers used in frac *** we compared analytical calculation results with Finite Element Analysis simulation using a simplified tubular geometry and showed the significant influences on interfacial friction on elastomer packer stress distribution,deformation,and contact stress after *** the demonstration of validity of FEA method,we conducted systematic numerical simulation studies to show how the interfacial friction coefficients can affect the maximum contact stress,average contact stress,contact stress distribution,and maximum mises stress for an actual packer used in plug *** addition,we also demonstrated how the groove in a packer can affect packer deformation and evolvement during setting with the consideration of interfacial *** study underscores the critical role that friction forces play in Frac plug performance and provides a new dimension for optimizing packer design by controlling interfacial interactions at the packer contact surfaces.

关键词： Elastomer seal Friction Sealing performance Contact stress

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Modeling human gastric cancers in immunocompetent mice

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Cancer Biology & Medicine 2024年第7期21卷 553-570页

作者： Weihong Zhang Shilong Wang hui Zhang Yan meng Shi Jiao Liwei An Zhaocai Zhou Department of Stomatology Department of Medical UltrasoundShanghai Tenth People's HospitalTongji University Cancer CenterTongji University School of MedicineShanghai 200072China State Key Laboratory of Genetic Engineering School of Life SciencesZhongshan HospitalFudan UniversityShanghai 200032China Collaborative Innovation Center for Cancer Personalized Medicine School of Public HealthNanjing Medical UniversityNanjing 211166China

Gastric cancer(GC)is a major cause of cancer-related mortality *** is determined by multiple(epi)genetic and environmental factors;can occur at distinct anatomic positions of the stomach;and displays high heterogeneity,with different cellular origins and diverse histological and molecular *** heterogeneity has hindered efforts to fully understand the pathology of GC and develop efficient *** the past decade,great progress has been made in the study of GC,particularly in molecular subtyping,investigation of the immune microenvironment,and defining the evolutionary path and *** mouse models,particularly immunocompetent models that mimic the cellular and molecular features of human GC,in combination with organoid culture and clinical studies,have provided powerful tools for elucidating the molecular and cellular mechanisms underlying GC pathology and immune evasion,and the development of novel therapeutic ***,we first briefly introduce current progress and challenges in GC study and subsequently summarize immunocompetent GC mouse models,emphasizing the potential application of genetically engineered mouse models in antitumor immunity and immunotherapy studies.

关键词： Gastric cancer heterogeneity mouse model GEMM immunocompetent

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