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Highly efficient transformation of intact yeast-like conidium cells of Tremella fuciformis by electroporation

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Science china(Life Sciences) 2008年第10期51卷 932-940页

作者： GUO LiQiong1.2, liu Yong1. {1. ShuXian1. liu ErXian1.& LIN JunFang1.2.1 college of Food Sciences, south china agricultural University, guangzhou 51.640, china 2 Institute of Biomass Research, south china agricultural University, guangzhou 51.640, china 1. college of Food Sciences South China Agricultural University Guangzhou 510640 China 2. Institute of Biomass Research South China Agricultural University Guangzhou 510640 China

Tremella fuciformis is one of higher basidiomycetes. Its basidiospore can reproduce yeast-like conidia, also called the blastospore by budding. The yeast-like conidia of T. fuciformis is monokaryotic and easy to culture by submerged fermentation similar to yeast. So it is a good recipient cell for exogenous gene expression. In this study, two expression vectors pGlg-gfp containing gpd-Gl promoter and gfp gene and pGlg-hph containing gpd-Gl promoter and hph gene were constructed. The lowest sensitive concentration of hygromycin for the blastospore was determined on three types of media. Our ex- periments showed that the lowest sensitive concentration of hygromycin for the blastospore was 5 μg/mL on MA medium. The intact blastospores were transformed with the expression vector pGlg-hph by electroporation. The putative transformants were obtained by the MA selective medium. Experi- mental results showed that the most effective parameters for the electroporation of intact blastospores were obtained by using STM buffer, 1.0×1.8 cells/mL of blastospores, 200 μL in transformation volume, 6 μg plasmid, 2.0 kV/cm of electric pulse voltage, stillness culturing on MB liquid medium for 48 h after electroporation. In these transformation conditions, the efficiency reached 277 colonies/μg DNA. Co-transformation of plasmid pGlg-gfp and pGlg-hph with ratio of 1.1.was performed by electroporation with the optimal parameters. The putative co-transformants were obtained by the MA selective medium. Eight randomly selected colonies from the vast putative co-transformants were analyzed by PCR de- tection and southern blotting. The experiments showed that the gfp was integrated into the genomes of three transformants. The co-transformation efficiency was 37.5%. Green fluorescence was observed under laser scanning confocal microscope in these gfp positive transformants. This indicates that the exogenous gfp can be expressed effectively in the yeast-like conidia of T. fuciformis.

关键词： Tremella fuciformis electroporation yeast-like conidia intact cells gene expression hph gene gfp gene

The deleterious effects and potential therapeutic strategy of fluorene-9-bisphenol on circadian activity and liver diseases in zebrafish and mice

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Journal of Environmental Sciences 2024年第11期145卷 13-27页

作者： Shuhui Zhang Xiang Zuo Jialu Luan Huijuan Bai zhenhua Fu Mingzhu Sun Xin {1. Xizeng Feng college of Life Science State Key Laboratory of Medicinal Chemical BiologyThe Key Laboratory of Bioactive MaterialsMinistry of EducationNankai UniversityTianjin 300071China Institute of Robotics&Automatic information System College of Artificial IntelligenceNankai UniversityTianjin 300071China

Increasing evidence indicates that disturbance of the clock genes,which leads to systemic endocrine perturbation,plays a crucial role in the pathogenesis of metabolic and liver ***-9-bisphenol(BHPF)is utilized in the manufacturing of plastic materials but its biological effects on liver homeostasis remain *** impacts and involved mechanisms of BHPF on the liver diseases,metabolism,and circadian clock were comprehensively studied by zebrafish andmouse *** therapeutic effect of melatonin(MT)was also *** and mousemodels with either acute exposure(0.5 and 1.mol/L,1.4 days post-fertilization)or chronic oral exposure(0.5 and 50 mg/(kg·2 days),30 days)were established with various BHPF ***,we identified a crucial role for estrogenic regulation in liver development and circadian locomotor rhythms damaged by BHPF in a zebrafish *** mice showed chaos in circadian activity through the imbalance of circadian clock component Brain and Muscle Aryl hydrocarbon receptor nuclear translocator-like 1.in the liver and *** liver sexual dimorphic alteration alongwith reduced growth hormone and estrogens played a critical role in damaged glucose metabolism,hepatic inflammation,and fibrosis induced by ***,sleep improvement by exogenous MT alleviated BHPF-related glucose metabolism and liver injury in *** proposed the pathogenesis of metabolic and liver disease resulting from BHPF and promising targeted therapy for livermetabolism disorders associated with endocrine perturbation *** results might play a warning role in the administration of endocrine-disrupting chemicals in everyday life and various industry applications.

关键词： Fluorene-9-bisphenol(BHPF) Melatonin Circadian activity Endocrine perturbation Liver diseases Female behavior Hepatic sexual dimorphism

Imaging theory of nonlinear second harmonic and third harmonic generations in confocal microscopy

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Science china(Physics,Mechanics & Astronomy) 2004年第1期47卷 8-16页

作者： TANG Zhilie1. XING Da2 & liu Songhao{1.. Department of Physics, south china Normal University, guangzhou 51.631. china 2. School for information and Optoelectronic Science and Engineering, south china Normal University, guangzhou 51.631. china Correspondence should be addressed to Tang Zhilie (email: tangzhl@***) Received April 23, 2003 1. Department of Physics South China Normal University 510631 Guangzhou China 2. School for information and Optoelectronic Science and Engineering South China Normal University 510631 Guangzhou China

The imaging theory of nonlinear second harmonic generation (SHG) and third harmonic generation (THG) in confocal microscopy is presented in this paper. The nonlinear effect of SHG and THG on the imaging properties of confocal microscopy has been analyzed in detail by the imaging theory. It is proved that the imaging process of SHG and THG in confocal microscopy, which is different from conventional coherent imaging or incoherent imaging, can be divided into two different processes of coherent imaging. The three-dimensional point spread functions (3D-PSF) of SHG and THG confocal microscopy are derived based on the nonlinear principles of SHG and THG. The imaging properties of SHG and THG confocal microscopy are discussed in detail according to its 3D-PSF. It is shown that the resolution of SHG and THG confocal microscopy is higher than that of single- and two-photon confocal microscopy.

关键词： second harmonic generation, third harmonic generation, confocal microscopy, three-dimensional point spread function.

An aperiodic phenomenon of the unscented Kalman filter in filtering noisy chaotic signals

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Progress in Natural Science:Materials International 2007年第10期17卷 1235-1240页

作者： Fan Hongjuan1. Feng Jiuchao1.2, Xie Shengli2 and Wang Shiyuan1.1. Faculty of Electronic and information Engineering ,{1.west University, Chongqing 40071., china 2. School of Electronic and information Engineering, {1. china University of Technology, guangzhou 51.641. china) Faculty of Electronic and information Engineering Southwest University Chongqing 400715 China School of Electronic and information Engineering South China University of Technology Guangzhou 510641 China

A non-periodic oscillatory behavior of the unscented Kalman filter (UKF) when used to filter noisy contaminated chaotic signals is reported. We show both theoretically and experimentally that the gain of the UKF may not converge or diverge but oscillate aperiodically. More precisely, when a nonlinear system is periodic, the Kalman gain and error covariance of the UKF converge to zero. However, when the system being considered is chaotic, the Kalman gain either converges to a fixed point with a magnitude larger than zero or oscillates aperiodically.

关键词： chaos unscented Kalman filter Lyapunov exponents aperiodicity.

Direct gray-scale extraction of topographic features for vein recognition

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Science china({1. Sciences) 2010年第10期53卷 2062-2074页

作者： KANG WenXiong 1. LI HuaSong 2 & DENG FeiQi 1.1.college of Automation Science and Engineering, {1. china University of Technology, guangzhou 51.640, china 2 School of information Engineering, Wuyi University, Jiangmen 529000, china 1. college of Automation Science and Engineering South China University of Technology Guangzhou 510640 China2. School of Information Engineering Wuyi University Jiangmen 529000 China

Binarization processing is a key step in most vein pattern recognition, but may create flaws such as leakage of some feature information. In order to overcome this problem, a new approach is explored in this paper which can extract topographic features directly from gray-scale vein images without binarization processing. First, an extreme graph of directional fields (EGDF) is calculated according to neighborhood information of every pixel, and then the intravenous main ridge of the image can be separated step by step from EGDF with the defined constraint template sets. After that, the sub-ridge is extracted from end points of the main ridge in range constraint image with the tracing method of maximal neighboring point. According to contrast experiment the proposed method is better than the traditional processing (performing binarization first and then skeletonization), in that it can overcome the problem that some separate vein lines are extracted incorrectly, and it can avoid extracting two neighboring vein lines as one ridge. As such, the proposed method is an effective way to extract topographic features for vein recognition

关键词： vein recognition feature extraction directional fields

Loss of energetic particles due to feedback control of resistive wall mode in HL-3

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Plasma Science and Technology 2024年第10期26卷 17-28页

作者： Yifei zhao Yueqiang {1. guangzhou HAO Zhengxiong WANG Guanqi DONG Shuo WANG Chunyu LI Guanming YANG Yutian MIAO Yongqin WANG Dalian University of Technology Dalian 116024People’s Republic of China General Atomics San Diego CA 92186-5608United States of America southwestern Institute of Physics Chengdu 610041People’s Republic of China

Effects of three-dimensional(3D)magnetic field perturbations due to feedback control of an unstable n=1.n is toroidal mode number)resistive wall mode(RWM)on the energetic particle(EP)losses are systematically investigated for the HL-3 *** MARS-F(liu et al 2000 *** 73681.code,facilitated by the test particle guiding center tracing module REORBIT,is utilized for the *** RWM is found to generally produce no EP loss for cocurrent particles in *** the same perturbation level at the sensor location for the close-loop system,feedback produces nearly the same loss of counter-current EPs compared to the open-loop *** however that the sensor signal is ten times smaller in the close-loop system than the open-loop counter part(reflecting the fact that the RWM is more stable with feedback),the counter-current EP loss is found significantly reduced in the *** of EP losses occur only for particles launched close to the plasma edge,while particles launched further away from the plasma boundary experience much less *** strike points of lost EPs on the HL-3 limiting surface become more scattered for particles launched closer to the plasma *** into account the full gyro-orbit of particles while approaching the limiting surface,REORBIT finds slightly enhanced loss fraction.

关键词： energetic particles resistive wall mode HL-3

Transitional function of DG to CA3 in the hippocampus

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Progress in Natural Science:Materials International 2007年第12期17卷 1436-1444页

作者： Yan Chuankui1.and liu Shenquan{1.. Department of Mathematics, Hangzhou Normal University, Hangzhou 31.036, china 2. Department of Applied Mathematics, School of Mathematical Sciences, south china University of Technology, guangzhou 51.640, china) Department of Mathematics Hangzhou Normal University Hangzhou 310036 China Department of Applied Mathematics School of Mathematical Sciences South China University of Technology Guangzhou 510640 China

Using single cell channel model, the transmission features of CA3-DG network in the hippocampus are investigated. The influence of the stimulation on discharge pattern of pyramidal neurons is analyzed, which shows that it starts with period spiking discharges, followed by period-doubling bifurcation to chaos, and period 3 discharge evolving into chaos, and ultimately a period of bursting discharges. By the synaptic model, the CA3-DG network model is constructed, which analyzes the summation of postsynaptic currents in the network, the influence of postsynaptic current on discharge rhythm as well as the mechanism of bursting discharges. The strong capacity of spatiotemporal encoding in the network indicates the features of CA3 network during the information transmission process in the hippocampus. The modeling result with time delay of the synaptic transmission is in accordance with the experimental phenomena of action potential in the hippocampus.

关键词： hippocampus CA3-DG period-doubling bifurcation chaos.

H2 /H∞ control of networked control system with random time delays

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Science china({1. Sciences) 2011年第12期54卷 2635-2650页

作者： QIU Li 1.2 , XU BuGong 1.& LI ShanBin 1.1.college of Automation Science and Engineering, {1. china University of Technology, guangzhou 51.640, china 2 college of Mechatronics and Control Engineering, Shenzhen University, Shenzhen 51.060, china 1. college of Automation Science and Engineering South China University of Technology Guangzhou 510640 China2. College of Mechatronics and Control Engineering Shenzhen University Shenzhen 518060 China

This paper investigates the H 2 /H ∞ control problem for a class of discrete-time networked control systems with random communication time delays. Both sensor-to-controller (S-C) and controller-to-actuator (C-A) random network-induced delays are considered. Two independent Markov chains are used to model the S-C and C-A random delays. The resulting closed-loop system is a jump linear time-delay system induced by two Markov chains. Sufficient conditions for existence of H 2 /H ∞ controller are established by free-weighting matrix and stochastic Lyapunov functions. A simulation example illustrates the effectiveness of the proposed method.

关键词： H 2 /H ∞ control networked control systems Markov chains random time delays

Linearly time-varying channel estimation and training power allocation for OFDM/MIMO systems using superimposed training

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Science china({1. Sciences) 2011年第7期54卷 1456-1470页

作者： ZHANG Han 1.DAI XianHua 2 & Pan DaRu 1.1.School of Physics and Telecommunication Engineering,south {1. Normal University,guangzhou 51.006,{1. 2 Department of information Science and Technology,SUN Yat-sen University,guangzhou 51.026,{1. 1. School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510006 China2. Department of Information Science and Technology SUN Yat-sen University Guangzhou 510026 China

We address the problem of estimating the linearly time-varying (LTV) channel of orthogonal frequency division multiplexing (OFDM)/multiple-input multiple-output (MIMO) systems using superimposed training (ST).The LTV channel is modeled by truncated discrete Fourier *** on this model,a two-step approach is adopted to estimate the LTV channel over multiple OFDM *** also present performance analysis of the channel estimation and derive a closed-form expression for the channel estimation *** is shown that the estimation variances,unlike that of the conventional ST-based schemes,approach to a fixed lower-bound as the training length increases,which is directly proportional to information-pilot power *** wireless communication systems with a limited transmission power,we optimize the ST power allocation by maximizing the lower bound of the average channel *** results show that the proposed approach outperforms the frequency-division multiplexed training schemes.

关键词： OFDM/MIMO systems linearly time-varying channel estimation superimposed training training power allocation