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On Proximinality of Convex Sets in Superspaces

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Acta Mathematica Sinica,English Series 2016年第6期32卷 633-642页

作者： Li Xin CHENG zheng Hua luo Wen ZHANG Ben Tuo zheng School of Mathematical Sciences Xiamen University School of Mathematical Sciences Huaqiao University Department of Mathematical Sciences the University of Memphis

Abstract In this paper, we show that a closed convex subset C of a Banach space is strongly proximinal （proximinal, resp.） in every Banach space isometrically containing it if and only if C is locally （weakly, resp.） compact. As a consequence, it is proved that local compactness of C is also equivalent to that for every Banach space Y isometrically containing it, the metric projection from Y to C is nonempty set-valued and upper semi-continuous.

关键词： Proximinality convex set local compactness Banach space

Image-Aided Analysis of Ballast Particle Movement Along a High-Speed Railway

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Engineering 2023年第8期27卷 161-177页

作者： Xuecheng Bian Wenqing Cai zheng luo Chuang Zhao Yunmin Chen Key Laboratory of Soft Soils and Geoenvironmental Engineering Ministry of EducationDepartment of Civil EngineeringZhejiang UniversityHangzhou 310058China Center for Hypergravity Experimental and Interdisciplinary Research Zhejiang UniversityHangzhou 310058China

As a core infrastructure of high-speed railways,ballast layers constituted by graded crushed stones feature noteworthy particle movement compared with normal railways,which may cause excessive settlement and have detrimental effects on train ***,the movement behavior remains ambiguous due to a lack of effective measurement approaches and analytical *** this study,an image-aided technique was developed in a full-scale model test using digital cameras and a colorbased identification approach.A total of 1274 surface ballast particles were manually dyed by discernible colors to serve as tracers in the *** movements of the surface ballast particles were tracked using the varied pixels displaying tracers in the photos that were intermittently taken during the test in the perpendicular *** movement behavior of ballast particles under different combinations of train speeds and axle loads was quantitatively *** obtained results indicated that the surface ballast particle movements were slight,mainly concentrated near sleepers under low-speed train loads and greatly amplified and extended to the whole surface when the train speed reached 360 ***,the development of ballast particle displacement statistically resembled its *** vibration contributed to the movements of ballast particles,which specifically were driven by vertical acceleration near the track center and horizontal acceleration at the track ***,the development trends of ballast particle movements and track settlement under long-term train loading were similar,and both stabilized at nearly the same *** track performance,including the vibration characteristics,accumulated settlement,and sleeper support stiffness,was determined to be closely related to the direction and distribution of ballast particle flow,which partly deteriorated under high-speed train loads.

关键词： High-speed railway Full-scale model test Image-aided technique Ballast particle movement Track vibration Accumulated settlement

Effect of solvent on the initiation mechanism of living anionic polymerization of styrene:A computational study

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Chinese Journal of Chemical Engineering 2024年第5期69卷 135-142页

作者： Shen Li Yin-Ning Zhou Zhong-Xin Liu zheng-Hong luo School of Chemical Engineering and Technology Hainan UniversityHaikou 570228China Department of Chemical Engineering School of Chemistry and Chemical EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China

For living anionic polymerization(LAP),solvent has a great influence on both reaction mechanism and *** this work,by using the classical butyl lithium-styrene polymerization as a model system,the effect of solvent on the mechanism and kinetics of LAP was revealed through a strategy combining density functional theory(DFT)calculations and kinetic *** terms of mechanism,it is found that the stronger the solvent polarity,the more electrons transfer from initiator to solvent through detailed energy decomposition analysis of electrostatic interactions between initiator and solvent ***,we also found that the stronger the solvent polarity,the higher the monomer initiation energy barrier and the smaller the initiation rate ***,initiation is more favorable at lower temperatures based on the calculated results ofΔG_(TS).Finally,the kinetic characteristics in different solvents were further examined by kinetic *** is found that in benzene and n-pentane,the polymerization rate exhibits first-order ***,slow initiation and fast propagation were observed in tetrahydrofuran(THF)due to the slow free ion formation rate,leading to a deviation from first-order kinetics.

关键词： Living anionic polymerization Solvent effect Reaction kinetics Computational chemistry Mathematical modeling Kinetic modeling

Measurement of K-Shell Ionization Cross Sections of Cr, Ni and Cu Atoms by 7.5-25 keV Electron Impact

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Chinese Physics Letters 2001年第11期18卷 1460-1462页

作者： AN Zhu TANG Chang-Huan luo zheng-Ming Key Laboratory for Radiation Physics and Technology of Ministry of Education Institute of Nuclear Science and TechnologySichuan UniversityChengdu 610064

The K-shell ionization cross sections of Cr, Ni and Cu elements by 7.5-25 keV electron impact have been *** experimental data have also been compared with the theoretical predictions of the Hippler and Mayol-Salvat mo... 详细信息

关键词： keV Electron Ionization

Zinc-α2-glycoprotein 1 attenuates non-alcoholic fatty liver disease by negatively regulating tumour necrosis factor-α

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World Journal of Gastroenterology 2019年第36期25卷 5451-5468页

作者： Ting Liu Xin luo zheng-Hong Li Jun-Cheng Wu Sheng-zheng luo Ming-Yi Xu Department of Gastroenterology Shanghai General Hospital Shanghai Jiao Tong University School of Medicine Shanghai 200080 China Department of Gastroenterology The Second Hospital of Hebei Medical University Shijiazhuang 050000 Hebei Province China Shanghai Key Laboratory of Pancreatic Diseases Shanghai General Hospital Shanghai Jiao Tong University School of Medicine Shanghai 200080 China

BACKGROUND Zinc-α2-glycoprotein 1 (AZGP1) plays important roles in metabolism-related diseases. The underlying molecular mechanisms and therapeutic effects of AZGP1 remain unknown in non-alcoholic fatty liver disease (NAFLD). AIM To explore the effects and potential mechanism of AZGP1 on NAFLD in vivo and in vitro. METHODS The expression of AZGP1 and its effects on hepatocytes were examined in NAFLD patients, CCl4-treated mice fed a high fat diet (HFD), and human LO2 cells. RESULTS AZGP1 levels were significantly decreased in liver tissues of NAFLD patients and mice. AZGP1 knockdown was found to activate inflammation;enhance steatogenesis, including promoting lipogenesis [sterol regulatory elementbinding protein (SREBP)-1c, liver X receptor (LXR), fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC), and stearoyl CoA desaturase 1 (SCD)-1], increasing lipid transport and accumulation [fatty acid transport protein (FATP), carnitine palmitoyl transferase (CPT)-1A, and adiponectin], and reducing fatty acid β-oxidation [farnesoid X receptor (FXR) and peroxisome proliferator-activated receptor (PPAR)-α];accelerate proliferation;and reverse apoptosis in LO2 cells. AZGP1 overexpression (OV-AZGP1) had the opposite effects. Furthermore, AZGP1 alleviated NAFLD by blocking TNF-α-mediated inflammation and intracellular lipid deposition, promoting proliferation, and inhibiting apoptosis in LO2 cells. Finally, treatment with OV-AZGP1 plasmid dramatically improved liver injury and eliminated liver fat in NAFLD mice. CONCLUSION AZGP1 attenuates NAFLD with regard to ameliorating inflammation, accelerating lipolysis, promoting proliferation, and reducing apoptosis by negatively regulating TNF-α. AZGP1 is suggested to be a novel promising therapeutic target for NAFLD.

关键词： Non-alcoholic fatty liver disease Zinc-α2-glycoprotein 1 Tumour necrosis factor-α Inflammation Lipid metabolism

MicroRNA-194 inactivates hepatic stellate cells and alleviates liver fibrosis by inhibiting AKT2

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World Journal of Gastroenterology 2019年第31期25卷 4468-4480页

作者： Jun-Cheng Wu Rong Chen Xin luo zheng-Hong Li Sheng-zheng luo Ming-Yi Xu Department of Gastroenterology Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China Shanghai Key Laboratory of Pancreatic Diseases Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China

BACKGROUND Activation of hepatic stellate cells(HSCs)is a pivotal event in the onset and progression of liver *** of microRNA-194(miR-194)has been reported in activated HSCs,but the actual role of miR-194 in liver fibrosis remains *** To explore the role and potential mechanism of miR-194-mediated regulation of liver fibrosis in vitro and in *** The expression of miR-194 was examined in human fibrotic liver tissues,activated HSCs,and a carbon tetrachloride(CCl4)mouse model by *** effects of AKT2 regulation by miR-194 on the activation and proliferation of HSCs were assessed in *** in vivo experiments,we reintroduced miR-194 in mice using a miR-194 agomir to investigate the functions of miR-194 in liver *** MiR-194 expression was notably lacking in activated HSCs from both humans and *** of miR-194(OV-miR-194)inhibitedα-smooth muscle actin(α-SMA)and type I collagen(Col I)expression and suppressed cell proliferation in HSCs by causing cell cycle arrest in G0/G1 ***2 was predicted to be a target of ***,the effects of miR-194 knockdown in HSCs were almost blocked by AKT2 deletion,indicating that miR-194 plays a role in HSCs via regulation of ***,miR-194 agomir treatment dramatically ameliorated liver fibrosis in CCl4-treated *** We revealed that miR-194 plays a protective role by inhibiting the activation and proliferation of HSCs via AKT2 *** results further propose miR-194 as a potential therapeutic target for liver fibrosis.

关键词： Hepatic stellate cells Liver fibrosis MicroRNA-194 AKT2

Curcumin Alleviates Hyperandrogenism and Promotes Follicular Proliferation in Polycystic Ovary Syndrome Rats:Insightson IRS1/PI3K/GLUT4 and PTEN Modulations

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Chinese Journal of Integrative Medicine 2022年第12期28卷 1088-1095页

作者： zheng luo CHEN Pei-fang DAI Wei-chao zheng Zhi-qun WANG Hui-lan Department of Gynecology and Obstetrics Fujian Medical University Union HospitalFuzhou 350001China

Objective:To explore the effect of curcuminon the insulin receptor substrate1(IRS1)/phosphatidylinositol-3-kinase(PI3K)/endometrial expression of glucose 4(GLUT4)signalling pathway and its regulator,phosphatase and tensin homolog(PTEN),in a rat model of polycystic ovarian syndrome(PCOS).Methods:PcoS model was induced by letrozole intragastric ***-Dawleyrats were randomized into 4groups according to a random number table:(1)control group;(2)PcoS group,which was subjected to PCOS and received vehicle;(3)curcumin group,which was subjected to PCoS and treated with curcumin(200 mg/kg for 2 weeks);and(4)curcumin+LY294002 group,which was subjected to PCOS,and treated with curcumin and LY294002(a specific PI3K inhibitor).Serum hormone levels(17β-estradiol,follicle stimulating hormone,luteinizinghormone,progesterone,and testosterone)were measured by enzyme linked immunosorbentassay,and insulin resistance(IR)was assessed using the homeostasismodel assessment of *** tissues were stained with haematoxylin and eosin for pathological and apoptosis *** levels of key transcriptional regulators and downstream targets,including IRS1,Pl3K,protein kinase B(AKT),GLUT4,and PTEN,were measured via reverse transcription polymerase chain reaction and Western blot,***:The Pcos group showed impaired ovarian morphology and *** with the PCoS group,curcumin treatment exerted ovarioprotective effects,down-regulated serum testosterone,restored IR,inhibited inflammatory cell infiltration in ovarian tissues,decreased IRS1,PI3K,and AKT expressions,and up-regulated GLUT4 and PTEN expressions in PCOS rats(P0.05).Conclusion:The beneficial effects of curcumin on PCOS rats included the alteration of serum hormone levels and recovery of morphological ovarian lesions,in which,PTEN,a new target

关键词： curcumin polycystic ovarian syndrome hyperandrogenism follicular proliferation insulin receptor substrate 1,phosphatidylinositol-3-kinase endometrial expression of glucose 4

Measurement and Correction of K-Shell Ionization Cross Sections for Copper and Gallium by Electron Impact

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Chinese Physics Letters 2001年第6期18卷 759-760页

作者： ZHOU Chang-Geng AN Zhu luo zheng-Ming Key Laboratory for Radiation Physics and Technology of Education Ministry Institute of Nuclear Science and TechnologySichuan UniversityChengdu 610064

The K-Shell ionization cross sections of Cu and Ga are measured by electron impact and the data of Ga are reported for the first *** method of a thin chemical compound target with a thick substrate is formally used in the *** influence of electrons reflected from the substrate is corrected by means of a calculation of electron transport.

关键词： experiment. formally Electron

Controlling reversible complexation-mediated polymerization(RCMP)via deep eutectic solvents:fast kinetics,narrow molecular weight distribution and mechanistic insights

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Science China Chemistry 2024年第8期67卷 2728-2736页

作者： Xin Fu Zhen Lu Shen Li zheng-Hong luo Lin-Xi Hou Department of Materials-Oriented Chemical Engineering College of Chemical EngineeringFuzhou UniversityFuzhou 350116China Department of Chemical Engineering School of Chemistry and Chemical EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200030China Chemical Engineering Zhicheng College of Fuzhou UniversityFuzhou 350116China Qingyuan Innovation Laboratory Quanzhou 362801China

The exploitation of new green polymerization avenues for the effective synthesis of polymers by reversible-deactivation radical polymerization plays a critical role in pursuing the development of polymeric *** this work,serials of deep eutectic solvents(DES)with intermolecular-hydrogen-bonding interaction were constructed as catalysts and medium for actuating reversible complexation-mediated polymerization(RCMP)for the first time,yielding methacrylate polymers with high monomer conversion and narrow dispersion molecular weight in both water and oil *** mechanism and elementary reaction of RCMP were explored deeply,revealing that the complexation of initiator with DES to generate radicals was a ratecontrolling step and intermolecular-hydrogen-bond was primary factor to influence polymerization ***,the insights of density functional theory calculations revealed that negative electrostatic potential ensured nucleophilic *** investigation demonstrated the considerable potential of DES for RCMP,which is anticipated for other polymerization applications as a novel medium mode.

关键词： deep eutectic solvent reversible complexation-mediated polymerization intermolecular hydrogen bonding density functional theory elementary reaction steps