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Changes of the tropical Pacific Walker circulation simulated by two versions of FgOALS model

Science China Earth Sciences 2014年第9期57卷 2165-2180页

作者： ma ShuangMei ZHOU TianJun LASg Institute of Atmospheric Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Climate Change Research Center Chinese Academy of Sciences

Here we assessed the performances of IAP/LASg climate system model FgOALS-g2 and FgOAS-s2 in the simulation of the tropical Pacific Walker circulation （WC）. Both models reasonably reproduce the climatological spatial distribution features of the tropical Pacific WC. We also investigated the changes of WC simulated by two versions of FgOALS model and discussed the mechanism responsible for WC changes. Observed Indo-Pacific sea level pressure （SLP） reveals a reduction of WC during 1900-2004 and 1950-2004, and an enhancement of WC during 1982-2004. During the three different time spans, the WC in FgOALS-g2 shows a weakening trend. In FgOALS-s2, tropical Pacific atmospheric circulation shows no significant change over the past century, but the WC strengthens during 1950-2004 and 1982-2004. The simulated bias of the WC change may be related to the phase of the multi-decadal mode in coupled models, which is not in sync with that in the observations. The change of WC is explained by the hydrological cycle constraints that precipitation must be balanced with the moisture trans- porting from the atmospheric boundary layer to the free troposphere. In FgOALS-g2, the increasing amplitude of the relative variability of precipitation （AP/P） is smaller （larger） than the relative variability of moisture （Aq/q） over the tropical western （eastern） Pacific over the three time spans, and thus leads to a weakened WC. In FgOALS-s2, the convective mass exchange fluxes increase （decrease） over the tropical western （eastern） Pacific over the past 53 a （1950-2004） and the last 23 a （1982- 2004）, and thus leads to a strengthened WC. The distributions of sea surface temperature （SST） trends dominate the change of WC. Over the past 55 a and 23 a, tropical Pacific SST shows an E1 Nifto-like （a La Nifia-like） trend pattern in FgOALS-g2 （FgOALS-s2）, which drives the weakening （strengthening） of WC. Therefore, a successful simulation of the tropical Pacific SST change pattern is necessary for a rea

关键词： Walker circulation FgOALS-g2 FgOALS-s2 historical climate simulation hydrological cycle constraint SST change pattern AMIP simulation

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graphs with vertex rainbow connection number two

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Science China mathematics 2015年第8期58卷 1803-1810页

作者： LU ZaiPing ma YingBin Center for Combinatorics LPMC-TJKLC Nankai University

An edge colored graph g is rainbow connected if any two vertices are connected by a path whose edges have distinct colors. The rainbow connection number of a graph g, denoted by rc(g), is the smallest number of colors that are needed in order to make g rainbow connected. A vertex colored graph g is vertex rainbow connected if any two vertices are connected by a path whose internal vertices have distinct colors. The vertex rainbow connection number of g, denoted by rvc(g), is the smallest number of colors that are needed in order to make g vertex rainbow connected. In 2011, Kemnitz and Schiermeyer considered graphs with rc(g) = *** investigate graphs with rvc(g) = 2. First, we prove that rvc(g) 2 if |E(g)|≥n-22 + 2, and the bound is sharp. Denote by s(n, 2) the minimum number such that, for each graph g of order n, we have rvc(g) 2provided |E(g)|≥s(n, 2). It is proved that s(n, 2) = n-22 + 2. Next, we characterize the vertex rainbow connection numbers of graphs g with |V(g)| = n, diam(g)≥3 and clique number ω(g) = n- s for 1≤s≤4.

关键词： vertex-coloring vertex rainbow connection number clique number

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Silk-based nerve guidance conduits with macroscopic holes modulate the vascularization of regenerating rat sciatic nerve

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Neural Regeneration Research 2025年第6期20卷 1789-1800页

作者： Carina Hromada Patrick Heimel markus Kerbl Lászlógál Sylvia Nürnberger Barbara Schaedl James Ferguson Nicole Swiadek Xavier Monforte Johannes C.Heinzel Antal Nógrádi Andreas H.Teuschl-Woller David Hercher Department Life Science Engineering University of Applied Sciences Technikum WienViennaAustria Austrian Cluster for Tissue Regeneration ViennaAustria Ludwig Boltzmann Institute for Traumatology The Research Center in Cooperation with AUVAViennaAustria University Clinic of Dentistry Medical University of ViennaViennaAustria Department of Plastic Reconstructive and Aesthetic SurgeryLandesklinikum Wiener Neustadt2700 Wiener NeustadtAustria Department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary Medical University of Vienna Department of Orthopedics and Trauma SurgeryDevision of Trauma SurgeryViennaAustria Department of Hand- PlasticReconstructive and Burn SurgeryBG Unfallklinik TuebingenUniversity of TuebingenTuebingenGermany

Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNgCs). However, the use of tNgCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNgC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNgCs and compared the various features of these improved silk^(+) tNgCs with the tubes without holes(silk^(–) tNgCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNgCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNgCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNgCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNgCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimizatio

关键词： axon regeneration blood vessel functional recovery macroporous nerve lesion peripheral nerve repair sciatic nerve silk-based nerve guidance conduit vascularization

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Experimental evidence for seismic nucleation phase

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Chinese Science Bulletin 2002年第9期47卷 769-773页

作者： ma Shengli ma Jin LIU Liqiang Institute of geology&Laboratory of Tectonophysics China Seismol-ogical BureauBeijing 100029China

The friction experiments on macroscopically homogeneous and non-homogeneous faults were performed by using a double-shear friction rig, and the waveforms of acoustic emission and the fault slip corresponding to the stick-slip instability events were analyzed. The results indicate that there exist two types of nucleation phase for stick-slip instability of non-homogeneous faults, and one is coincident with the preslip model, the other with the cascade model. It is concluded that the seismic nucleation phase exists objectively, and its generation is related to heterogeneity of fault.

关键词： earthquake nucleation phase friction experiment acoustic emission fault slip.

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Use genetic Programming to Rank Web Images

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China Communications 2010年第1期7卷 80-92页

作者： Li Piji ma Jun Shandong Univ Sch Comp Sci & Technol Jinan 250101 Peoples R China

Web image retrieval is a challenging task. One central problem of web image retrieval is to rank a set of images according to how well they meet the user information need. The problem of learning to rank has inspired numerous approaches to resolve it in the text information retrieval, related work for web image retrieval, however, are still limited. We focus on the problem of learning to rank images for web image retrieval, and propose a novel ranking model, which employs a genetic programming architecture to automatically generate an effective ranking function, by combining various types of evidences in web image retrieval, including text information, image visual content features, link structure analysis and temporal information. The experimental results show that the proposed algorithms are capable of learning effective ranking functions for web image retrieval. Significant improvement in relevancy obtained, in comparison to some other well-known ranking techniques, in terms of maP, NDCg@n and D@n.

关键词： web image retrieval learning to ranking temporal information genetic programming results diversity

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Immobilized Lentinus edodes residue as absorbent for the enhancement of cadmium adsorption performance

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Frontiers of Environmental Science & Engineering 2012年第4期6卷 498-508页

作者： Pei ma Dan ZHANg Institute of geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China graduate University of Chinese Academy of Sciences Beijing 100049China Institute of Mountain Hazards and Environment Chinese Academy of Sciences and Ministry of Water ConservancyChengdu 610041China

To investigate the potential use of Lentinus edodes （L. edodes） residue for Cd^2＋ adsorption, poly alcohol Na alginate （PVA） was applied to immobilize it. The parameters including contact time, pH, adsorbent dosages, and coexisting metal ions were studied. The suitable pH for immobilized L. edodes was 4-7 wider than that for raw L. edodes （pH 6-7）. In the presence of Pb^2＋ concentration varying from 0 to 30mg.L^-1, the Cd^2＋ adsorption ratios declined by 6.71% and 47.45% for immobilized and raw L. edodes, respectively. While, with the coexisting ion Cu2＋ concentration varied from 0 to 30 mg.L^-1, the Cd^2＋ adsorption ratios declined by 12.97% and 50.56% for immobilized and raw L. edodes, respectively. The Cd^2＋ adsorption isotherms in singlemetal and dual-metal solutions were analyzed by using Langmuir, Freuxldlich, and Dubinin-Radushkevich models. The Cd^2＋ adsorption capacities （qm） in single-metal solution were 6.448 mg.L^-1 and 2.832 mg.L^-1 for immobilized and raw L. edodes, respectively. The qm of immobilized L. edodes were 1.850 mg Cd. gl in Cd^2＋＋ Pb^2＋ solution and 3.961mg Cd.g^-1 in Cd^2＋＋ Cu^2＋ solution, respectively. The Cd^2＋ adsorption processes subjected to both adsorbents follow pseudo-second-order model. Mechanism study showed the functional group of L. edodes was -OH, -NH, -CO, and PVA played an important role in metal adsorbing. Mining wastewater treatment test showed that PVA-SA-immobilized L. edodes was effective in mixed pollutant treatment even for wastewater containing metal ions in very low concentration.

关键词： competitive immobilization Lentinus edodes residue adsorption isotherm

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Development of Novel Supported gold Catalysts： A materials Perspective

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Nano Research 2011年第1期4卷 3-32页

作者： Zhen ma Sheng Dai Department of Environmental Science and Engineering Fudan University Shanghai 200433 China Chemical Sciences Division Oak Ridge National Laboratory Oak Ridge TN 37831 USA

Since Haruta et al. discovered that small gold nanoparticles finely dispersed on certain metal oxide supports can exhibit surprisingly high activity in CO oxidation below room temperature, heterogeneous catalysis by supported gold nanoparticles has attracted tremendous attention. The majority of publications deal with the preparation and characterization of conventional gold catalysts （e.g., Au/TiO2）, the use of gold catalysts in various catalytic reactions, as well as elucidation of the nature of the active sites and reaction mechanisms. In this overview, we highlight the development of novel supported gold catalysts from a materials perspective. Examples, mostly from those reported by our group, are given concerning the development of simple gold catalysts with single metal-support interfaces and heterostructured gold catalysts with complicated interfacial structures. Catalysts in the first category include active Au/SiO2 and Au/metal phosphate catalysts, and those in the second category include catalysts prepared by pre-modification of supports before loading gold, by post-modification of supported gold catalysts, or by simultaneous dispersion of gold and an inorganic component onto a support. CO oxidation has generally been employed as a probe reaction to screen the activities of these catalysts. These novel gold catalysts not only provide possibilities for applied catalysis, but also furnish grounds for fundamental research.

关键词： gold nanoparticles catalyst design catalyst support functionalization promotion CO oxidation

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Characterization and application of a recombinant dopa decarboxylase from Harmonia axyridis for the efficient biosynthesis of dopamine

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Chinese Journal of Chemical Engineering 2022年第1期35卷 449-456页

作者： Siyuan gao Yuanke guo Chen ma Ding ma Kequan Chen Pingkai Ouyang Xin Wang State Key Laboratory of materials-Oriented Chemical Engineering College of Biotechnology and Pharmaceutical EngineeringNanjing Tech UniversityNanjing 211816China

Here,a dopa decarboxylase(DDC)from Harmonia axyridis was heterogeneously expressed in Escherichia coli for the efficient biosynthesis of *** the production of recombinant DDC,the cultivation conditions including IPTg concentration,temperature and induction time were optimized and obtained an optimal specific enzyme activity of 51.72 U·mg^(-1) crude *** the purification of DDC with a recovery yield of 68.79%,its activity was further *** Vmax,Km,Kcat,and Kcat/Km of DDC for d ihyd roxy pheny la la nine(dopa)were 0.02 mmol·ml^(-1)·s^(-1),2.328 mmol·ml^(-1),10435.90 s^(-1) and4482.77 ml,mmol *** highest DDC activity was observed at the condition of pH 7.5 and 45℃.With the purified DDC,the feasibility to produce dopamine from L-dopa was *** optimal yield was determined at the following bioconversion conditions:pH of 7,0,the reaction temperature of 40℃,0.4 mmol·L^(-1) of PLP and 4 g·L^(-1) of L-dopa,Subsequently,a fed-batch process for the production of dopamine was developed and the effect of oxygen was *** titer,yield and productivity of dopamine reached up to 21.99 g·L^(-1)80.88%and 14.66 g·L^(-1)·h^(-1) at 90 min under anaerobic condition.

关键词： Dopa decarboxylase Dopamine Enzyme catalysis Fed-batch bioconversion

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Palm vein recognition method based on fusion of local gabor histograms

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The Journal of China Universities of Posts and Telecommunications 2017年第6期24卷 55-66页

作者： ma Xin Jing Xiaojun School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

gabor features have been shown to be effective for palm vein recognition. This paper presents a novel feature representation method, implementing the fusion of local gabor histograms （FLgH）, in order to improve the accuracy of palm vein recognition systems. A new local descriptor called local gabor principal differences patterns （LgPDP） encodes the gabor magnitude using the local maximum difference （LMD） operator. The corresponding gabor phase patterns are encoded by local gabor exclusive OR （XOR） patterns （LgXP）. Fisher＇s linear discriminant （FLD） method is then implemented to reduce the dimensionality of the feature representation. Low-dimensional gabor magnitude and phase feature vectors are finally fused to enhance accuracy. Experimental results from Institute of Automation, Chinese Academy of sciences （CASIA） database show that the proposed FLgH method achieves better performance by utilizing score-level fusion. The equal error rate （EER） is 0.08%, which outperforms other conventional palm vein recognition methods （EER range from 2.87% to 0.16%）, e.g., the Laplacian palm, minutiae feature, Hessian phase, Eigenvein, local invariant features, mutual foreground local binary patterns （LBP）, and multi-sampling feature fusion methods.

关键词： palm vein recognition gabor filter local histogram Fisher's linear discriminant

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Ultra-wide band gap and wave attenuation mechanism of a novel star-shaped chiral metamaterial

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Applied mathematics and Mechanics(English Edition) 2024年第7期45卷 1261-1278页

作者： Shuo WANg Anshuai WANg Yansen WU Xiaofeng LI Yongtao SUN Zhaozhan ZHANg Qian DINg g.D.AYALEW Yunxiang ma Qingyu LIN Department of Mechanics Tianjin UniversityTianjin300350China Tianjin Key Laboratory of Nonlinear Dynamics and Control Tianjin UniversityTianjin300350China State Key Laboratory of Metastable materials Science and Technology Yanshan UniversityQinhuangdao066004Hebei ProvinceChina

A novel hollow star-shaped chiral metamaterial(SCM)is proposed by incorporating chiral structural properties into the standard hollow star-shaped metamaterial,exhibiting a wide band gap over 1500 *** broaden the band gap,solid single-phase and two-phase SCMs are designed and simulated,which produce two ultra-wide band gaps(approximately 5116 Hz and 6027 Hz,respectively).The main reason for the formation of the ultra-wide band gap is that the rotational vibration of the concave star of two novel SCMs drains the energy of an elastic *** impacts of the concave angle of a single-phase SCM and the resonator radius of a two-phase SCM on the band gaps are *** the concave angle leads to an increase in the width of the widest band gap,and the width of the widest band gap increases as the resonator radius of the two-phase SCM ***,the study on elastic wave propagation characteristics involves analyzing frequency dispersion surfaces,wave propagation directions,group velocities,and phase ***,the analysis focuses on the transmission properties of finite periodic *** solid single-phase SCM achieves a maximum vibration attenuation over 800,while the width of the band gap is smaller than that of the two-phase *** metamaterials exhibit high vibration attenuation capabilities,which can be used in wideband vibration reduction to satisfy the requirement of ultra-wide frequencies.

关键词： metamaterial ultra-wide band gap wave propagation vibration suppression

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