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Supercritical fluid-assisted fabrication of C-doped Co_(3)O_(4) nanoparticles based on polymer-coated metal salt nanoreactors for efficient enzyme-mimicking and glucose sensor properties

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Nano Research 2023年第5期16卷 7431-7442页

作者： Ze-wen kang Jun-Yu Zhang Ze-Zhen Li Ranjith Kumar Kankala Shi-Bin Wang Ai-Zheng Chen Institute of Biomaterials and Tissue Engineering Huaqiao UniversityXiamen 361021China Fujian Provincial Key Laboratory of Biochemical Technology(Huaqiao University) Xiamen 361021China Instrumental Analysis Center Laboratory and Equipment Management DepartmentHuaqiao UniversityXiamen 361021China

Nanomaterials doped with non-metallic C have attracted tremendous attention as potential nano-artificial enzymes due to their ability to change the energy band structure to improve their intrinsic ***,we report a green,facile,efficient,fast strategy to access high-performance nanozymes via supercritical CO_(2)fluid technology-fabricated polymer nanoreactor of poly-(methyl vinyl ether-co-maleic anhydride)(PVM/MA)coated Co(NO_(3))_(2)into C-doped Co_(3)O_(4)(C-Co_(3)O_(4))nanozyme by a onestep calcination *** PVM/MA to C doping into Co_(3)O_(4)shortens the entire lattice constant of the crystal structure,and the overall valence band energy level below the Fermi level shifts toward the lower energy *** as-prepared CCo_(3)O_(4)demonstrated significant peroxidase-like catalytic activity,significantly greater than the undoped Co_(3)O_(4)nanoparticle *** following density functional theory(DFT)calculations revealed that the doped nano-enzyme catalytic site displayed a unique electronic structure,altering the material surface with more electrons to fill the anti-bond of the two molecular orbitals,significantly improving the peroxidase-like enzyme catalytic and glucose sensor *** resultant enzymatic glucose sensing in a linear range of 0.1–0.6 mM with a detection limit of 3.86μM is in line with standard Michaelis–Menten ***,this work demonstrates that converting polymers into nanozymes of C-doped form by supercritical CO_(2)fluid technology in a step is an effective strategy for constructing high-performance glucose sensor *** cost-effective,reliable,precise system offers the potential for rapid analyte detection,facilitating its application in a variety of fields.

关键词： supercritical fluid poly-(methyl vinyl ether-co-maleic anhydride)(PVM/MA) C-doped Co_(3)O_(4) nanozymes density functional theory(DFT)calculation

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Microstructure and Corrosion Behavior of the As-Extruded Mg-4Zn-2Gd-0.5Ca Alloy

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Acta Metallurgica Sinica(English Letters) 2020年第3期33卷 362-374页

作者： Hao-Yi Niu Fang-Fang Cao Kun-Kun Deng Kai-Bo Nie Jin-wen kang Hong-Wei Wang Shanxi Key Laboratory of Advanced Magnesium-Based Materials College of Materials Science and EngineeringTaiyuan University of TechnologyTaiyuan 030024China

In order to study the corrosion resistance of extruded magnesium alloys,the Mg-4Zn-2Gd-0.5Ca alloy was extruded at the speed of 0.01-0.1 mm/s with the temperature of 280-360℃in present *** extrusion results show that the volume fraction of precipitates(Vpre),VDRX(the dynamic recrystallization rate) and the average size of DRXed grain(dDRX) decrease with the decrease in extrusion speed,and the corrosion rate of the alloy also shows a downward *** the contrary,the values of Vpre,VDRX and dDRX increase with the increase in extrusion temperature,and the corrosion resistance of Mg-4Zn-2Gd-0.5Ca alloy *** the extrusion speed is 0.01 mm/s and the extrusion temperature is 280℃,the alloy has the best corrosion *** corrosion of extruded Mg-4Zn-2Gd-0.5Ca alloy occurs preferentially on the magnesium matrix around W and I phases in the DRXed *** the further corrosion,the corrosion continues to spread along the phase,and the corrosion area gradually *** corrosion plays a leading role in the corrosion ***,there are a large number of basal plane textures in the unDRXed region,which is conducive to improving the corrosion resistance of magnesium *** addition,the decrease in grain size also makes the corrosion of magnesium alloy more uniform.

关键词： Mg-4Zn-2Gd-0.5Ca alloy Extrusion EIS(electrochemical impedance spectroscopy) Weight loss Corrosion resistance

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Asymmetric transmission of acoustic waves in a waveguide via gradient index metamaterials

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Science Bulletin 2019年第12期64卷 808-813页

作者： wen-kang Cao Li-Ting Wu Cheng Zhang Jun-Chen Ke Qiang Cheng Tie-Jun Cui Yun Jing State Key Laboratory of Millimeter Waves Department of Radio EngineeringSoutheast UniversityNanjing 210096China Department of Mechanical and Aerospace Engineering North Carolina State UniversityRaleighNC 27695USA

We demonstrate that asymmetric acoustic wave transmission in a waveguide can be achieved via gradient index metamaterials(GIMs). We theoretically prove that the acoustic wave can be efficiently converted to surface waves(SWs) via GIMs. The GIMs in a waveguide can allow the transmission of acoustic waves in one direction but block them in the other direction. This theory is validated by experiments. Our findings may provide new applications in various scenarios such as high-efficiency acoustic couplers and noise control.

关键词： Asymmetric transmission Surface waves Gradient index metamaterials Waveguide

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FedFV: A Personalized Federated Learning Framework for Finger Vein Authentication

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Machine Intelligence Research 2023年第5期20卷 683-696页

作者： Feng-Zhao Lian Jun-Duan Huang Ji-Xin Liu Guang Chen Jun-Hong Zhao wen-Xiong kang School of Automation Science and Engineering South China University of TechnologyGuangzhou 510641China GRG Banking Equipment Co.Ltd. Guangzhou 510663China School of Automation Guangdong University of Petrochemical TechnologyMaoming 525000China

Most finger vein authentication systems suffer from the problem of small sample ***,the data augmentation can alleviate this problem to a certain extent but did not fundamentally solve the problem of category *** the researchers resort to pre-training or multi-source data joint training methods,but these methods will lead to the problem of user privacy *** view of the above issues,this paper proposes a federated learning-based finger vein authentication framework(FedFV)to solve the problem of small sample size and category diversity while protecting user *** training under FedFV,each client can share the knowledge learned from its user′s finger vein data with the federated client without causing template *** addition,we further propose an efficient personalized federated aggregation algorithm,named federated weighted proportion reduction(FedWPR),to tackle the problem of non-independent identically distribution caused by client diversity,thus achieving the best performance for each *** thoroughly evaluate the effectiveness of FedFV,comprehensive experiments are conducted on nine publicly available finger vein *** results show that FedFV can improve the performance of the finger vein authentication system without directly using other client *** the best of our knowledge,FedFV is the first personalized federated finger vein authentication framework,which has some reference value for subsequent biometric privacy protection research.

关键词： Finger vein personalized federated learning privacy protection biometric authentication.

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High expression of the circadian clock gene NPAS2 is associated with progression and poor prognosis of gastric cancer:A singlecenter study

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World Journal of Gastroenterology 2023年第23期29卷 3645-3657页

作者： Xiao-Meng Cao wen-Di kang Tian-Hong Xia Shao-Bin Yuan Chang-An Guo wen-Jie Wang Hong-Bin Liu Department of General Surgery Gansu Provincial Hospital of TCMLanzhou 730050Gansu ProvinceChina The First Clinical Medical College Gansu University of Chinese MedicineLanzhou 730030Gansu ProvinceChina Department of Interventional Therapy National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Clinical Medicine College Ningxia Medical UniversityClinical Medicine collegeNingxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina Department of Emergency Lanzhou University Second HospitalLanzhou 730030Gansu ProvinceChina Department of General Surgery Lanzhou University Second HospitalLanzhou 730030Gansu ProvinceChina Department of General Surgery The 940^(th)Hospital of Joint Logistics Support Force of Chinese People's Liberation ArmyLanzhou 730050Gansu ProvinceChina

BACKGROUND The prognostic assessment of patients after surgical resection of gastric cancer(GC)patients is ***,the role of the circadian clock gene NPAS2 expression in GC remains *** To explore the relationship between NPAS2 and the survival prognosis of GC patients and clarify its role in evaluating GC *** The tumor tissues and clinical data of 101 patients with GC were collected *** staining(IHC)was used to detect the expression of NPAS2 protein in GC and adjacent *** and multivariate Cox regression analysis was used to determine the independent prognostic factors of GC,and a nomogram prediction model was *** receiver operating characteristic(ROC)curve,the ROC area under the curve,the calibration curve,and C-index were used to evaluate the predictive effectiveness of the *** Meier analysis was used to compare the risk stratification of subgroups according to the median score in the nomogram model of each *** Microarray IHC analysis showed that the positive rate of NPAS2 protein expression in GC tissues was 65.35%,which was significantly higher than 30.69%in adjacent *** high expression of NPAS2 was correlated with tumor-node-metastasis(TNM)stage(P<0.05),pN stage(P<0.05),metastasis(P<0.05),venous invasion(P<0.05),lymphatic invasion(P<0.05),and lymph node positive(P<0.05)of *** Meier survival analysis showed that the 3-year overall survival(OS)of patients with high NPAS2 expression was significantly shortened(P<0.0001).Univariate and multivariate COX regression analysis showed that TNM stage(P=0.009),metastasis(P=0.009),and NPAS2 expression(P=0.020)were independent prognostic factors of OS in GC patients for 3 *** nomogram prediction model based on independent prognostic factors has a C-Index of 0.740(95%CI:0.713-0.767).Furthermore,subgroup analysis showed that the 3-year OS time of the high-risk group was significantly lower than th

关键词： NPAS2 Gastric cancer Tissue microarray Survival analysis Prediction model Nomogram

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Microstructure and mechanical properties of Mg-4Zn-xGd(x=0,0.5,1,2)alloys

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Journal of Magnesium and Alloys 2020年第2期8卷 441-451页

作者： Cui-ju Wang Jin-wen kang Kun-kun Deng Kai-bo Nie Wei Liang Wei-guo Li Shanxi Key laboratory of advanced magnesium-based materials College of Materials Science and EngineeringTaiyuan University of TechnologyTaiyuan 030024PR China Engineering training center Taiyuan University of TechnologyTaiyuan 030024PR China

The present work inainly focuses on tlie effect of minor cofiteut of Gd cicmcnt on the micrGstmcturc and mechanical properties of Mg Zn *** Mg-4Zn-xGd(x=0,0.5,1,2)alloys were fabricated and subjected to extrusion at 280℃ with the ratio of 25:*** revealed that the addition of Gd could inhibit the dynamic recrystallization(DRX)of Mg-4Zn alloy,and both the size and volume fraction of DRXed grains demonstrated a decreasing tendency as the Gd content increased from 0.5 to 2 wt.%.It is the weakening effect on DRX behavior that lead to the smaller amount of fine precipitate and the stronger texture *** compared with the Mg-4Zn alloy,the yield strength and ultimate tensile strength of Mg-4Zn-xGd alloys were improved obviously by the addition of minor content of Gd,however,at the expense of *** tensile properties with the yield strength of〜369.8 MPa and ultimate tensile strength of〜400.3 MPa were obtained when the Gd content was 2 wt.%.

关键词： Magnesium alloy Dynamic recrystallization Dynamic precipitation Microstructure Mechanical properties

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High electrocatalytic hydrogen evolution activity on a coupled Ru and CoO hybrid electrocatalyst

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Journal of Energy Chemistry 2019年第10期28卷 143-147页

作者： Jia-Xin Guo Dong-Yang Yan kang-wen Qiu Chuan Mu Dian Jiao Jing Mao Hui Wang Tao Ling Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education Tianjin Key Laboratory of Composite and Functional MaterialsSchool of Materials Science and EngineeringTianjin UniversityTianjin 300072China Key Laboratory of Aerospace Materials and Performance(Ministry of Education) School of Materials Science and EngineeringBeihang UniversityBeijing 100191China

Hydrogen evolution reaction (HER) is an essential step in converting renewable energy to clean hydrogen fuel. Exploring highly efficient, stable and cost-effective electrocatalysts is of crucial significance for sustainable HER. Here, we report the design of a coupled ruthenium/cobalt oxide (Ru/CoO) hybrid electrocatalyst for alkaline HER. In this hybrid metal/oxide system, the complicated alkaline HER pathways are overall facilitated;oxygen (O)-vacancy-abundant oxide enhances water splitting and Ru promotes successive hydrogen intermediates to generate hydrogen. The resulting Ru/CoO hybrid electrocatalyst exhibits significantly promoted catalytic activity compared with benchmark Ru catalyst, displaying an overpotential of 55 mV to generate a HER current density of 10 mA cm^-2, comparable with the state-of-the-art Pt/C catalyst and the most efficient alkaline HER electrocatalysts. Furthermore, the strong interaction of Ru nanoparticles with oxide support and the in-situ growth of oxide support on conductive substrate guarantee the long-term stability of as-fabricated Ru/CoO hybrid electrocatalyst. This newly designed hybrid catalyst with abundant metal/oxide interfaces may pave a new pathway for exploring efficient and stable HER electrocatalysts.

关键词： Ruthenium Oxides Hybrid electrocatalyst Hydrogen evolution reaction

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Improvement of Impact Toughness and Creep Properties in Reduced Activation Ferritic Steels by Consumable Electrode Remelting

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Journal of Iron and Steel Research International 2013年第6期20卷 45-51页

作者： kang wen-yi ZHANG Chi FAN Nian-qing XIA Zhi-xin WANG Ping-huai CHEN Ji-ming Department of Materials Science and Engineering University of Science and Technology Beijing Department of Materials Science and Engineering Tsinghua University Suzhou Nuclear Power Research Institute Southwestern Institute of Physics

The effect of smelting processes on mechanical properties and microstructure of reduced activation ferritic steels was *** properties and impact toughness of reduced activation ferritic steels were obviously improved by vacuum induction melting followed by consumable electrode remelting process in comparison with the conventional vacuum induction melting *** difference of impact toughness and creep properties between both steels mainly depended on the aspect ratio and mean size of *** the aspect ratio of carbides makes development of a shear band more difficult , which could increase impact energy and creep resistance.

关键词： reduced activation steel consumable electrode remelting microstructure creep fracture

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Effects of extracellular vesicles from mesenchymal stem cells on oxygen-glucose deprivation/reperfusioninduced neuronal injury

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World Journal of Emergency Medicine 2021年第1期12卷 61-67页

作者： Shuang-shuang Gu Xiu-wen kang Jun Wang Xiao-fang Guo Hao Sun Lei Jiang Jin-song Zhang Department of Emergency the First Affi liated Hospital of Nanjing Medical UniversityNanjing 210029China Key Laboratory of Modern Toxicology Ministry of EducationDepartment of ToxicologySchool of Public HealthNanjing Medical UniversityNanjing 211166China

BACKGROUND: Small extracellular vesicles (sEVs) from bone marrow mesenchymal stemcells (BMSCs) have shown therapeutic potential for cerebral ischemic diseases. However, themechanisms by which BMSC-derived sEVs (BMSC-sEVs) protect neurons against cerebral ischemia/reperfusion (I/R) injury remain unclear. In this study, we explored the neuroprotective effects ofBMSC-sEVs in the primary culture of rat cortical neurons exposed to oxygen-glucose deprivation andreperfusion (OGD/R) ***: The primary cortical neuron OGD/R model was established to simulate the processof cerebral I/R in vitro. Based on this model, we examined whether the mechanism through whichBMSC-sEVs could rescue OGD/R-induced neuronal ***: BMSC-sEVs (20 μg/mL, 40 μg/mL) significantly decreased the reactive oxygenspecies (ROS) productions, and increased the activities of superoxide dismutase (SOD) and glutathioneperoxidase (GPx). Additionally, BMSC-sEVs prevented OGD/R-induced neuronal apoptosis in vivo, asindicated by increased cell viability, reduced lactate dehydrogenase (LDH) leakage, decreased terminaldeoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) staining-positivecells, down-regulated cleaved caspase-3, and up-regulated Bcl-2/Bax ratio. Furthermore, Westernblot and flow cytometry analysis indicated that BMSC-sEV treatment decreased the expression ofphosphorylated calcium/calmodulin-dependent kinase II (p-CaMK II)/CaMK II, suppressed the increaseof intracellular calcium concentration ([Ca2+]i) caused by OGD/R in ***: These results demonstrate that BMSC-sEVs have signifi cant neuroprotectiveeff ects against OGD/R-induced cell injury by suppressing oxidative stress and apoptosis, and Ca2+/CaMK II signaling pathways may be involved in this process.

关键词： Oxygen-glucose deprivation and reperfusion Cortical neurons Oxidative stress Small extracellular vesicles

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Progress in clinical trials of cell transplantation for the treatment of spinal cord injury:how many questions remain unanswered?

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Neural Regeneration Research 2021年第3期16卷 405-413页

作者： Xu-Chang Hu Yu-Bao Lu Yong-Na Yang Xue-wen kang Yong-Gang Wang Bing Ma Shuai Xing Key Laboratory of Bone and Joint Diseases Research of Gansu Province Department of OrthopedicsLanzhou University Second HospitalLanzhouGansu ProvinceChina Second Clinical Medical College Lanzhou UniversityLanzhouGansu ProvinceChina Department of Neurology The First People’s Hospital of Lanzhou CityLanzhouGansu ProvinceChina

Spinal cord injury can lead to severe motor,sensory and autonomic nervous ***,there is currently no effective treatment for spinal cord *** stem cells and progenitor cells,bone marrow mesenchymal stem cells,olfactory ensheathing cells,umbilical cord blood stem cells,adipose stem cells,hematopoietic stem cells,oligodendrocyte precursor cells,macrophages and Schwann cells have been studied as potential treatments for spinal cord *** treatments were mainly performed in ***,subtle changes in sensory function,nerve root movement and pain cannot be fully investigated with animal *** these cell types have shown excellent safety and effectiveness in various animal models,sufficient evidence of efficacy for clinical translation is still *** transplantation should be combined with tissue engineering scaffolds,local drug delivery systems,postoperative adjuvant therapy and physical rehabilitation training as part of a comprehensive treatment plan to provide the possibility for patients with SCI to return to normal *** review summarizes and analyzes the clinical trials of cell transplantation therapy in spinal cord injury,with the aim of providing a rational foundation for the development of clinical treatments for spinal cord injury.

关键词： central nervous system clinical trials injury plasticity protection regeneration repair spinal cord stem cells

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