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Neural Regeneration Research 2025年第7期20卷 2108-2115页

作者： Yuhui Kou Zongxue Jin Yusong Yuan Bo ma Wenyong Xie na Han Department of Trauma and Orthopedics Peking University People’s HospitalBeijingChina national Center for Trauma Medicine Peking University People’s HospitalBeijingChina Key Laboratory of Trauma and Neural Regeneration(Peking University) Ministry of EducationBeijingChina Trauma Medicine Center Peking University People’s HospitalBeijingChina Department of Orthopedics China-Japan Friendship HospitalBeijingChina

FK506(Tacrolimus)is a systemic immunosuppressant approved by the *** and Drug ***506 has been shown to promote peripheral nerve regeneration,however,its precise mechanism of action and its pathways remain *** this study,we established a rat model of sciatic nerve injury and found that FK506 improved the morphology of the injured sciatic nerve,increased the numbers of motor and sensory neurons,reduced inflammatory responses,markedly improved the conduction function of the injured nerve,and promoted motor function *** findings suggest that FK506 promotes peripheral nerve structure recovery and functional regeneration by reducing the intensity of inflammation after neuronal injury and increasing the number of surviving neurons.

关键词： FK506 inflammation motor neurons nerve regeneration neuron peripheral nerve injury sensory neurons

ASYMPTOTIC BEHAVIOR OF THE TE AND TM APPROXImaTIONS TO SECOND HARMONIC GENERATION

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Journal of Computational mathematics 2007年第1期25卷 49-66页

作者： na■ma A■ssa Faculté de mathématiques USTHBBP32El AliaBab Ezzouar16111Alger Centre de mathématiques Appliquées CNRS UMR 7641■Ecole PolytechniquePalaiseau 91128 CedexFrance

We consider a Second Harmonic Generation （SHG） problem of an optical signal wave with an optical pump in a medium represented by a smooth bounded domain Ω→∩ IR^d which is assumed to contain a heterogeneous material： a compactly imbedded subdomain B^r →∩∩ in the shape of a small ball contains a nonlinear material, while Ω／ B^r is filled with a linear material. We begin by proving existence and uniqueness of the solution to the TE approximation of SHG for arbitrary bounded susceptibilities, thus improving the result obtained by Bao and Dobson （ Eur. J. Appl. math. 6 （1995）, 573-590） under small enough susceptibilities assuption. We then establish an existence and uniqueness result of a solution to the TM approximation problem. In both parts we study the asymptotic behavior of the system as the size of the nonlinear material vanishes： error estimates and asymptotic expansion of the solution are derived for both TE and TM approximations.

关键词： Second harmonic generation TE Approximation TM Approximation.

Quantum Wolf Pack Evolutionary Algorithm of Weight Decision-making Based on Fuzzy Control

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Chinese Journal of Electronics 2022年第4期31卷 635-646页

作者： LU na ma Long School of Economics and management Xi’an Aeronautical University

In the traditional quantum wolf pack algorithm, the wolf pack distribution is simplified, and the leader wolf is randomly selected. This leads to the problems that the development and exploration ability of the algorithm is weak and the rate of convergence is ***, a quantum wolf pack evolutionary algorithm of weight decision-making based on fuzzy control is proposed in this paper. First, to realize the diversification of wolf pack distribution and the regular selection of the leader wolf, a dual strategy method and sliding mode cross principle are adopted to optimize the selection of the quantum wolf pack initial position and the candidate leader wolf. Second, a new non-linear convergence factor is adopted to improve the leader wolf’s search direction operator to enhance the local search capability of the algorithm. Meanwhile, a weighted decision-making strategy based on fuzzy control and the quantum evolution computation method is used to update the position of the wolf pack and enhance the optimization ability of the algorithm. Then, a functional analysis method is adopted to prove the convergence of the quantum wolf pack algorithm, thus realizing the feasibility of the algorithm’s global convergence. The performance of the quantum wolf pack algorithm of weighted decision-making based on fuzzy control was verified through six standard test functions. The optimization results are compared with the standard wolf pack algorithm and the quantum wolf pack algorithm. Results show that the improved algorithm had a faster rate of convergence, higher convergence precision,and stronger development and exploration ability.

关键词： fuzzy control optimisation Optimisation techniques leader wolf Combinatorial mathematics quantum evolution computation wolf pack distribution search direction operator local search capability evolutionary computation decision making Applications of systems theory Fuzzy control nonlinear convergence factor optimization ability quantum wolf pack evolutionary algorithm search problems weighted decision-making strategy

POSITIVE DEFINITE AND SEMI-DEFINITE SPLITTING METHODS FOR NON-HERMITIAN POSITIVE DEFINITE LINEAR SYSTEMS

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Journal of Computational mathematics 2016年第3期34卷 300-316页

作者： na Huang Changfeng ma School of mathematics and Computer Science Fujian Normal University Fuzhou 350117 China

In this paper, we further generalize the technique for constructing the normal （or pos- itive definite） and skew-Hermitian splitting iteration method for solving large sparse non- Hermitian positive definite system of linear equations. By introducing a new splitting, we establish a class of efficient iteration methods, called positive definite and semi-definite splitting （PPS） methods, and prove that the sequence produced by the PPS method con- verges unconditionally to the unique solution of the system. Moreover, we propose two kinds of typical practical choices of the PPS method and study the upper bound of the spectral radius of the iteration matrix. In addition, we show the optimal parameters such that the spectral radius achieves the minimum under certain conditions. Finally, some numerical examples are given to demonstrate the effectiveness of the considered methods.

关键词： Linear systems Splitting method Non-Hermitian matrix Positive definitematrix Positive semi-definite matrix Convergence analysis.

Microstructural Characteristics of Epitaxial BaSrNb_(0.3)Ti_(0.7)O_3 Film

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Journal of materials Science & Technology 2007年第4期23卷 517-520页

作者： Li＇na CHENG Xiuliang ma Shenyang national Laboratory for materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Microstructural characteristics in the BaSrNb0.3Ti0.7O3 thin film, grown on SrTiO3 substrate by computercontrolled laser molecular beam epitaxy, were characterized by means of transmission electron microscopy （TEM）. It is found that the film is single-crystallized and epitaxially grown on the SrTiO3 substrate forming a flat and distinct interface. Anti-phase domains were identified, and the crystallographic features of mismatch dislocations at the interface between film and substrate were clarified. The high conductivity of the present film was discussed from the viewpoint of Nb dopant and the nitrogen atmosphere.

关键词： BaSrNb0.3Ti0.7O3 thin film Epitaxial growth Transmission electron microscopy TEM

The electrochemical reforming of glycerol at Pd nanocrystals modified ultrathin NiO nanoplates hybrids:An efficient system for glyceraldehyde and hydrogen coproduction

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nano Research 2022年第3期15卷 1934-1941页

作者： Ge ma na Yang Guofu Zhou Xin Wang South China Academy of Advanced Optoelectronics and International Academy of Optoelectronics at Zhaoqing South China Normal UniversityGuangzhou 510631China

The glycerol electro-oxidation reaction(GEOR)is a green and promising method for the glyceraldehyde *** this work,Pd nanocrystals(Pd-NCs)modified ultrathin NiO nanoplates(NiO-uNPs)hybrids(Pd-NCs/NiO-uNPs)are successfully synthesized using successive cyanogel hydrolysis,chemical reduction,and calcination treatment *** electrochemical measurements and physicochemical characterization results demonstrate that Pd-NCs/NiO-uNPs hybrids have excellent electrocatalytic performance for both GEOR and hydrogen evolution reaction(HER)in alkaline medium,which benefit from the large specific surface area,uniform distribution of Pd-NCs,and the modified electronic structure of Ni *** Pd-NCs/NiO-uNPs hybrids,only 1.43 V is needed to obtain the current density of 100 ma∙cm^(−2) for GEOR,much lower than that for oxygen evolution reaction(1.82 V).In addition,Pd-NCs/NiO-uNPs hybrids exhibit better HER performance than commercial Pd/C *** a result,the constructed Pd-NCs/NiO-uNPs||Pd-NCs/NiO-uNPs glycerol electrolyzer only requires 1.62 V electrolysis voltage to reach 10 ma∙cm^(−2) current density,showing an energy-efficient and economy-competitive synthesis for the coproduction of glyceraldehyde and hydrogen.

关键词： NiO nanoplates Pd nanocrystals synergistic effect glycerol electro-oxidation reaction hydrogen evolution reaction

Migration of bisphenol A and its related compounds in canned seafood and dietary exposure estimation

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Food Quality and Safety 2022年第2期6卷 275-286页

作者： na Lin Derong ma Zhidong Liu Xichang Wang Liyan ma East China Sea Fisheries Research Institute Chinese Academy of Fishery SciencesShanghaiChina Shanghai Ocean University ShanghaiChina

The present study sought to investigate the migration of target bisphenols,such as bisphenol-A(BPA),bisphenol-F(BPA),bisphenol-A diglycidyI ether(BADGE),bisphenol-A(2,3-dihydroxypropyl)glycidyl ether(BADGE.H_(2)O),bisphenol-A bis(2,3-dihydroxypropyl)ether(BADGE.2H_(2)O),and bisphenol F diglycidyl ether(BFDGE)in 102 samples of several canned seafood,namely canned Antarctic krill,scallop,oysters,mussel,clam,and mantis shrimp stored for months at different temperatures through a high-performance liquid chromatographic-fluorescence detector com-bined with a microwave-assisted extraction *** for BFDGE,the other five bisphenols were observed in most of the analyzed *** canned shrimp showed the highest migration of BPA(0.089 mg/kg),exceeding the specific migration limit(SML)of BPA(0.05 mg/kg)specified by the European Union,while the migration levels of BADGE and its derivatives were within their *** migration behavior of bisphenols in the canned seafood was majorly affected by the analytes,storage conditions,and food ***,BADGE.H_(2)O,and BADGE 2H_(2)O were characterized by a rapid migration during the first half of the shelf life,which increased with the increase of temperature,followed by a stabilization or decline of their concentrations for prolonged ***,the migration of target bisphenols was significantly influenced by the storage temperature in some seafood ***,higher migration level of BPA was found in samples with higher fat *** average dietary exposure of Chinese adults to BPA,BPF,BADGE.2H_(2)O,BADGE.H_(2)O,and BADGE of canned seafood was estimated at 11.69,1.21,6.47,8.74,and 4.71 ng/(kg d),*** target hazard quotient values of all the analyzed bisphenols were below 1 for the Chinese adults,suggesting an insignificant exposure to these bisphenols through canned seafood consumption.

关键词： Bisphenol-A(BPA) BPA-related compounds canned seafood migration behavior dietary exposure

Peroxisome proliferator-activated receptor-γ is essential in the pathogenesis of gastric carcinoma

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World Journal of Gastroenterology 2009年第31期15卷 3874-3883页

作者： Xiu-Mei ma Hong Yu na Huai Department of Pathology The First Affiliated Hospital of Inner Mongolia Medical College Huhhot 010059 Inner Mongolia Autonomous Region China Department of Pathology School of Basic Medical Sciences of Inner Mongolia Medical College Huhhot 010059 Inner Mongolia Autonomous Region China The Graduate Faculty of Inner Mongolia Medical College Huhhot 010059 Inner Mongolia Autonomous Region China

AIM： To investigate whether peroxisome proliferatoractivated receptor γ （PPAR-γ） is expressed in human gastric carcinoma and whether PPAR-γ, is a potential target for gastric carcinoma therapy. METHODS： PPAR-γ protein in gastric carcinoma was examined by immunohistochemistry. In the gastric carcinoma cell line MGCS03, PPAR-7, survivin, Skp2 and p27 protein and mRna were examined by Western blotting and real-time reverse transcription-polymerase chain reaction, respectively; proliferation was examined by MTT; apoptosis was examined by chromatin staining with Hoechst 33342 and fluorescence activated cell sorting （FACS）. and cell cycle was examined by FACS; the knockdown of PPAR-γ was done by Rna interference. RESULTS： A high level of expression of PPAR-γ was observed in human gastric carcinoma and in a human gastric carcinoma cell line MGCS03. The PPAR-γ agonist 15-deoxy-△12,14-prostaglandin J2 （15d-PGJ2）inhibited growth, and induced apoptosis and G1/G0 cell cycle arrest in MGC803 cells in a concentration-dependent and time-dependent manner. The effect of 15d-PGJ2 on MGC803 cells was not reversed by the selective and irreversible antagonist GW9662 for PPAR-γ. Furthermore, survivin and Skp2 expression were decreased, whereas p27 expression was enhanced following 15d-PGJ2 treatment in a dose-dependent manner in MGC803 cells. Interestingly, we also found that small interfering Rna for PPAR-γ inhibited growth and induced apoptosis in MGC803 cells. The inhibition of PPAR-γ function may be a potentially important and novel modality for treatment and prevention of gastric carcinoma. CONCLUSION： A PPAR-γ agonist inhibited growth of human gastric carcinoma MGC803 cells by inducing apoptosis and G1/G0 cell cycle arrest with the involvement of survivin, Skp2 and p27 and not via PPAR-γ.

关键词： Peroxisome proliferator-activated receptor Gastric cancer Apoptosis Cell cycle

In vitro thyroid disrupting effects of organic extracts from WWTPs in Beijing

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Journal of Environmental Sciences 2011年第4期23卷 671-675页

作者： na Li Mei ma Kaifeng Rao Zijian Wang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China.

It is generally known that there are many endocrine disrupting compounds （EDCs） in the effluents from wastewater treatment plants （WWTPs）. Most research has focused on the occurrence of estrogenic or androgenic activities, while ignoring that there are environmental chemicals disrupting thyroid system, which is essential for growth and development in both humans and animals. In the present work, a two-hybrid yeast assay was conducted to evaluate the removal efficiencies of agonistic or antagonistic thyroid receptor （TR） mediated effects in different treatment processes of three WWTPs located in Beijing. We found no TR agonistic, but TR antagonistic activities in all processes from the WWTPs. The TR antagonistic activities in organic extracts of water samples were then calibrated regarding to a known TR-inhibitor, amiodarone hydrochloride （AH）. The observed concentration of TR disrupting substances ranged from 2.35 × 10 8 to 6.19 × 10 7 mol/L AH in Gaobeidian WWTP, 3.76 × 10 8 to 8.75 × 10 8 mol/L AH in Lugouqiao WWTP, and 4.80 × 10 9 to 2.55 × 10 8 mol/L AH in Beixiaohe WWTP. Of the three WWTPs, the removal rates were 92.7%, 42.2%, and 23.1% respectively. Industrial sewage may contain more TR disrupting substances compared with domestic sewage. The recipient waters were found to contain considerable concentrations of TR disrupting substances that may cause adverse effects on the exposed organisms.

关键词： recombinant yeast assay thyroid receptor wastewater

Catalytic combustion of soot particulates over La_(2-x)K_xNiMnO_6 catalysts

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Journal of natural Gas Chemistry 2011年第4期20卷 384-388页

作者： Wenjuan Shan Jiali Yang Lihua Yang na ma Institute of Chemistry for Functionalized materials College of Chemistry and Chemical Engineering Liaoning Normal University Dalian 116029 Liaoning China

nanosized La2-xKxNiMnO6 catalysts with ABO3 type perovskite-like structure were prepared by auto-combustion method using citric acid as a ligand to control particle size and *** structures and properties of these perovskite-like oxides were investigated by X-ray powder diffraction（XRD）and temperature-programmed reduction（TPR）.The catalytic activities for soot combustion were evaluated by temperature- programmed oxidation（TPO）with pure O2 and O2/NOx as oxidant,*** the La2-xKxNiMnO6 catalysts,the partial substitution of K at A-site leads to an increase of the concentrations of high valence cation and oxygen vacancy,which enhance the catalytic activity for soot *** optimal substitution amount of K was equal to x=0.4 among these ***（peak temperature）in O2-TPO profile was 420-C and Tp in O2/NOx-TPO profile was 370-C over La1.6K0.4NiMnO6 catalyst for soot particulates combustion under loose contact conditions between catalyst and soot.

关键词： soot oxidation La2-xKxNiMnO6 perovskite-like active oxygen