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Human umbilical cord mesenchymal stem cells derivedexosomes on VEGF-A in hypoxic-induced mice retinal astrocytes and mice model of retinopathy of prematurity

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1238-1247页

作者： Xiao-Tian Zhang Bo-Wen Zhao Yuan-Long Zhang Song Chen Tianjin Eye Hospital Tianjin 300020China Tianjin Key lab of Ophthalmology and Visual science Tianjin 300020China

AIM:To observe the effect of human umbilical cord mesenchymal stem cells(hUCMSCs)secretions on the relevant factors in mouse retinal astrocytes,and to investigate the effect of hUCMSCs on the expression of vascular endothelial growth factor-A(VEGF-A)and to observe the therapeutic effect on the mouse model of retinopathy of prematurity(ROP).METHODS:Cultured hUCMSCs and extracted exosomes from them and then retinal astrocytes were divided into control group and hypoxia *** assay,flow cytometry,reverse transcription-polymerase chain reaction(RT-PCR)and Western blot were used to detect related *** mechanisms by which hUCMSCs exosomes affect VEGF-A expression in hypoxia-induced mouse retinal astrocytes were *** last,the efficacy of exosomes of UCMSCs in a mouse ROP model was ***6 was used to comprehensively process data ***:The secretion was successfully extracted from the culture supernatant of hUCMSCs by gradient *** oxygen species(ROS)and hypoxia inducible factor-1α(HIF-1α)of mice retinal astrocytes under different hypoxia time and the expression level of VEGF-A protein and VEGF-A mRNA increased,and the ROP cell model was established after 6h of *** secretions of medium and high concentrations of hUCMSCs can reduce ROS and HIF-1α,the expression levels of VEGF-A protein and VEGF-A mRNA are statistically significant and concentration *** with the ROP cell model group,the expression of phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT)/mammalian target of rapamycin(mTOR)signal pathway related factors in the hUCMSCs exocrine group is significantly *** intravitreal injection of the secretions of medium and high concentrations of hUCMSCs can reduce VEGF-A and HIF-1αin ROP model *** staining shows that the number of retinal neovascularization in ROP mice decreases with the increase of the dose of hUCMSCs ***:In a hypoxia induced

关键词： human umbilical cord mesenchymal stem cells retinal astrocytes retinopathy of prematurity vascular endothelial growth factor hypoxia inducible factor

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Understanding the spatial interaction of ultrasounds based on three-dimensional dual-frequency ultrasonic field numerical simulation

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china Foundry 2024年第1期21卷 29-43页

作者： Zhao-yang Yin Qi-chi Le Yan-chao Jiang Da-zhi Zhao Qi-yu Liao Qi Zou Key lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China School of Materials science and Engineering Northeastern UniversityShenyang 110819China

A transient 3D model was established to investigate the effect of spatial interaction of ultrasounds on the dual-frequency ultrasonic field in magnesium alloy *** effects of insertion depth and tip shape of the ultrasonic rods,input pressures and their ratio on the acoustic field distribution were discussed in ***,the spacing,angle,and insertion depth of two ultrasonic rods significantly affect the interaction between distinct *** a result,various acoustic pressure distributions and cavitation regions are *** spherical rods mitigate the longitudinal and transversal attenuation of acoustic pressure and expand the cavitation volume by 53.7%and 31.7%,respectively,compared to the plate and conical *** the input pressure will enlarge the cavitation region but has no effect on the acoustic pressure distribution *** acoustic pressure ratio significantly affects the pressure distribution and the cavitation region,and the best cavitation effect is obtained at the ratio of 2:1(P15:P20).

关键词： dual-frequency ultrasonic numerical model acoustic pressure spatial interaction magnesium alloy

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Answering reachability queries with ordered label constraints over labeled graphs

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Frontiers of Computer science 2024年第1期18卷 105-117页

作者： Daoliang HE Pingpeng YUAN Hai JIN National Engineering Research Center for Big Data Technology and System Services Computing Technology and System LabCluster and Grid Computing LabSchool of Computer Science&TechnologyHuazhong University of Science and TechnologyWuhan 430074China

Reachability query plays a vital role in many graph analysis *** researches proposed many methods to efficiently answer reachability queries between vertex *** many real graphs are labeled graph,it highly demands label-Constrained Reachability(LCR)query inwhich constraint includes a set of labels besides vertex *** researches proposed several methods for answering some LCR queries which require appearance of some labels specified in constraints in the *** that constraint may be a label set,query constraint may be ordered labels,namely OLCR(Ordered-label-Constrained Reachability)queries which retrieve paths matching a sequence of ***,no solutions are available for ***,we propose DHL,a novel bloom filter based indexing technique for answering OLCR *** can be used to check reachability between vertex *** the answers are not no,then constrained DFS is ***,we employ DHL followed by performing constrained DFS to answer OLCR *** show that DHL has a bounded false positive rate,and it's powerful in saving indexing time and *** experiments on 10 real-life graphs and 12 synthetic graphs demonstrate that DHL achieves about 4.8-22.5 times smaller index space and 4.6-114 times less index construction time than two state-of-art techniques for LCR queries,while achieving comparable query response *** results also show that our algorithm can answer OLCR queries effectively.

关键词： graph ordered-label-constrained reachability partial index bloom filter query processing

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Grain size refinement of additive manufactured Ce-TZP ceramics by coupled two-step pre-sintering and HIP

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Journal of Advanced Ceramics 2024年第5期13卷 621-629页

作者： Ruoshi Zhao Hongbing Yang Xintong Liu Hezhen Li Chang-An Wang Jing Ma Yanhao Dong State Key lab of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Ceria-stabilized tetragonal zirconia polycrystal(Ce-TZP)has exceptional fracture toughness and flaw tolerance due to facile t‒m phase transformation ***,its wider-range applications are limited by its relatively low strength due to its large grain size and low transformation stress,which results in yield-like ***,we combined additive manufacturing(AM),pressureless two-step sintering,and hot isostatic pressing(HIP),and addressed the challenging grain size refinement problem in *** successfully produced dense ultrafine-grained Ce-TZP ceramics with an average grain size below 500 nm,a three-point bending strength above 800 MPa,and a single-edge-notch-beam fracture toughness in the range of 11‒12 MPa·m^(1/2).The critical roles of processing design,mixed Ce valences,and ***-stabilization of tetragonal polymorphs were *** work offers insights and strategies for the future development of stronger and tougher Ce-TZP ceramics that can compete with tetragonal yttria-stabilized zirconia in various applications,including additive manufacturing.

关键词： zirconia additive manufacturing(AM) two-step sintering hot isostatic pressing(HIP) grain size refinement

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Heterointerface engineering of rhombic Rh nanosheets confined on MXene for efficient methanol oxidation

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Journal of Energy Chemistry 2024年第6期93卷 419-428,I0011页

作者： Qi Zhang Quanguo Jiang Xiang Yang Chi Zhang Jian Zhang Lu Yang Haiyan He Guobing Ying Huajie Huang College of Materials science and Engineering Hohai UniversityNanjing 210098JiangsuChina New Energy Technology Engineering lab of Jiangsu Province College of ScienceNanjing University of Posts&Telecommunications(NUPT)Nanjing 210023JiangsuChina School of Materials science and Engineering Southeast UniversityNanjing 211100JiangsuChina

Although metallic rhodium(Rh)is regarded as a promising platinum-alternative anode catalyst of direct methanol fuel cell(DMFC),the conventional"particle-to-face"contact model between Rh and matrix largely limits the overall electrocatalytic performance due to their insufficient cooperative ***,we report a controllable and robust heterointerface engineering strategy for the bottom-up fabrication of rhombic Rh nanosheets in situ confined on Ti_3C_(2)T_x MXene nanolamellas(Rh NS/MXene)via a convenient stereoassembly *** unique design concept gives the resulting 2D/2D Rh NS/MXene heterostructure intriguing textural features,including large accessible surface areas,strong"face-toface"interfacial interactions,homogeneous Rh nanosheet distribution,ameliorative electronic structure,and high electronic *** a consequence,the as-prepared Rh NS/MXene nanoarchitectures exhibit exceptional electrocatalytic methanol oxidation properties in terms of a large electrochemically active surface area of 126.2 m~2 g_(Rh)~(-1),a high mass activity of 1056.9 mA mg_(Rh)-~1,and a long service life,which significantly outperform those of conventional particle-shaped Rh catalysts supported by carbon black,carbon nanotubes,reduced graphene oxide,and MXene matrixes as well as the commercial Pt nanoparticle/carbon black and Pd nanoparticle/carbon black catalysts with the same noble metal loading *** functional theory calculations further demonstrate that the direct electronic interaction at the well-contacted 2D/2D heterointerfaces effectively enhances the adsorption energy of Rh nanosheets and induces a left shift of the d-band center,thereby making the Rh NS/MXene configuration suffer less from CO *** work highlights the importance of rational heterointerface design in the construction of advanced noble metal/MXene electrocatalysts,which may provide new avenues for developing the next-generation DMFC devices.

关键词： Rhodium nanosheet Ti_(3)C_(2)T_(x)MXene Heterointerface Electrocatalyst Fuel cell

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Data-driven discovery of linear dynamical systems from noisy data

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science china(Technological sciences) 2024年第1期67卷 121-129页

作者： WANG YaSen YUAN Ye FANG HuaZhen DING Han School of Mechanical science and Engineering Huazhong University of Science and TechnologyWuhan 430074China State Key lab of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China Department of Mechanical Engineering University of KansasLawrence 66045USA

In modern science and engineering disciplines,data-driven discovery methods play a fundamental role in system modeling,as data serve as the external representations of the intrinsic mechanisms within ***,empirical data contaminated by process and measurement noise remain a significant obstacle for this type of *** this study,we have developed a data-driven method capable of directly uncovering linear dynamical systems from noisy *** method combines the Kalman smoothing and sparse Bayesian learning to decouple process and measurement noise under the expectation-maximization framework,presenting an analytical method for alternate state estimation and system ***,the discovered model explicitly characterizes the probability distribution of process and measurement noise,as they are essential for filtering,smoothing,and stochastic *** have successfully applied the proposed algorithm to several simulation *** results demonstrate its potential to enable linear dynamical system discovery in practical applications where noise-free data are intractable to capture.

关键词： system identification sparse Bayesian learning Kalman smoothing process and measurement noise

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Core–Shell Microfiber Encapsulation Enables Glycerol‑Free Cryopreservation of RBCs with High Hematocrit

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Nano-Micro Letters 2024年第1期16卷 35-54页

作者： Xianhui Qin Zhongrong Chen Lingxiao Shen Huilan Liu Xilin Ouyang Gang Zhao Department of Electronic Engineering and Information science University of Science and Technology of ChinaHefei 230027People’s Republic of China School of Biomedical Engineering Anhui Medical UniversityHefei 230022People’s Republic of China Department of Blood Transfusion The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001People’s Republic of China The Fourth Medical Center Chinese PLA General HospitalBeijing 100089People’s Republic of China

Cryopreservation of red blood cells(RBCs)provides great potential benefits for providing transfusion timely in *** concentrations of glycerol(20%or 40%)are used for RBC cryopreservation in current clinical practice,which results in cytotoxicity and osmotic injuries that must be carefully ***,existing studies on the low-glycerol cryopreservation of RBCs still suffer from the bottleneck of low hematocrit levels,which require relatively large storage space and an extra concentration process before transfusion,making it inconvenient(time-consuming,and also may cause injury and sample lose)for clinical *** this end,we develop a novel method for the glycerol-free cryopreservation of human RBCs with a high final hematocrit by using trehalose as the sole cryoprotectant to dehydrate RBCs and using core–shell alginate hydrogel microfibers to enhance heat transfer during *** from previous studies,we achieve the cryopreservation of human RBCs at high hematocrit(>40%)with high recovery(up to 95%).Additionally,the washed RBCs post-cryopreserved are proved to maintain their morphology,mechanics,and functional *** may provide a nontoxic,high-efficiency,and glycerol-free approach for RBC cryopreservation,along with potential clinical transfusion benefits.

关键词： Cryopreservation Human red blood cells Core-shell microfibers Trehalose Hematocrit

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Analysis of amino acid enantiomers in ambient aerosols:Effects and removal of coexistent aerosol matrix

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Journal of Environmental sciences 2024年第3期137卷 732-740页

作者： Ying Li Xiaoying Li Libin Wu Luhan Shi ShanWang Pingqing Fu Yingyi Zhang Senchao Lai The Key lab of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of EducationSchool of Environment and EnergySouth China University of TechnologyGuangzhou 510006China Institute of Surface-Earth System science School of Earth System ScienceTianjin UniversityTianjin 300072China now at Hong Kong University of science and Technology Hong Kong 00852China

Amino acids(AAs)including D-and L-enantiomers are a group of organic nitrogen species in ambient *** to the low abundances of AAs(level of ng/m^(3))and the matrix effects by coexistent components,it is challenging to quantify AA enantiomers in ambient aerosols especially under pollution *** this study,we present an optimized method for analyzing AA enantiomers in atmospheric aerosol samples including a pretreatment process and the detection by high performance liquid chromatography coupled to a fuorescence detector(HPLC-FLD).Matrix effects caused by coexistent chemicals on AA enantiomers analysis in ambient aerosol samples were investigated especially for those collected in pollution *** results revealed that the determination of AA enantiomers is significantly affected by the coexistent organic carbon(as a proxy of organic matter)and water-soluble ion of NH_(4)^(+).To remove the matrix effects,we applied a pretreatment using the solid phase extraction column coupled with alkaline adjustment to sample *** pretreatment,18 AAs including 6 pairs of D-and L-enantiomers(i.e.,leucine,isoleucine,valine,alanine,serine,and aspartic acid)can be successfully separated and quantified in aerosol samples by *** recoveries are in the range of 67%-106%.This method was successfully applied to the urban aerosol samples from pollution and non-pollution periods for AA enantiomers *** suggest that the concentrations of D-AAs and the ratio of D-AA/L-AA are indicative of the contribution of bacterial sources and the infuence of biomass burning.

关键词： Amino acid enantiomers Atmospheric aerosol Organic carbon Ammonia Chiral ratio

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Prestoring lithium into SnO_(2)coated 3D carbon fiber cloth framework as dendrite-free lithium metal anode

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Particuology 2024年第1期84卷 89-97页

作者： Tao Wei Yanyan Zhou Cheng Sun Lesheng Liu Sijia Wang Mengting Wang Ye Liu Qing Huang Quanchao Zhuang Yongfu Tang School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang212003China College of Materials science and Engineering Nanjing Forestry UniversityNanjing210037China Li-ion Batteries lab School of Materials Science and EngineeringChina University of Mining and TechnologyXuzhouChina Hebei Key laboratory of Applied Chemistry School of Environmental and Chemical EngineeringYanshan UniversityQinhuangdao066004China

For several decades,the promise of implementing of lithium(Li)metal anodes has been regarded as the"holy grail"for Li-based ***,we have proposed a facile design of a carbon fiber cloth(CFC)framework coated with SnO_(2)nanoparticles through a hydrothermal process,which served as a reliable host for prestoring molten Li to produce a CFC@SnO_(2)@Li composite ***,TEM,HRTEM,XPS and different electrochemical characterizations were carried *** to the synergetic effects of the 3D conductive CFC and the coated lithiophilic SnO_(2)nanoparticles,the designed CFC@SnO_(2)@Li electrodes can buffer the volume changes and reduce the local current density,thus suppress the Li dendrites during ***,the CFC@SnO_(2)electrodes showed a high and stable CE of 98.6%for 1000 cycles at a current density of 1 mA cm^(-2)(1 mAh cm^(-2)).What is more,at a high current density of 5 mA cm^(-2)and a high areal capacity of 5 mAh cm^(-2),the symmetric cell displayed relatively low overpotential and long cycling lifetime of 1600 *** results confirm its great potential as lithium metal anodes in practical battery applications.

关键词： Lithiophilic Lithium metal anodes SnO_(2) 3D anode Dendrite-free

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Quantum Tunneling Enhanced Hydrogen Desorption from Graphene Surface: Atomic versus Molecular Mechanism

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Chinese Physics Letters 2024年第8期41卷 58-68页

作者： Yangwu Tong Yong Yang science Island Branch of Graduate School University of Science and Technology of ChinaHefei 230026China Key lab of Photovoltaic and Energy Conservation Materials Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China

We study the desorption mechanism of hydrogen isotopes from graphene surface using first-principles calculations,with focus on the effects of quantum *** low temperatures,quantum tunneling plays a dominant role in the desorption process of both hydrogen monomers and *** the case of dimer desorption,two types of mechanisms,namely the traditional one-step desorption in the form of molecules(molecular mechanism),and the two-step desorption in the form of individual atoms(atomic mechanism),are studied and *** the ortho-dimers,the dominant desorption mechanism is found to switch from the molecular mechanism to the atomic mechanism above a critical temperature,which is∼300K and 200K for H and D,respectively.

关键词： desorption quantum mechanism

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