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Discrete Conley index and bifurcation points

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Journal of Shanghai university(English Edition) 2010年第6期14卷 400-404页

作者：王凯华傅新楚 Department of Mathematics College of SciencesShanghai University college of Mathematics and Statistics Hainan Normal University

In this paper, a sufficient condition for the existence of bifurcation points for discrete dynamical systems is presented. The relation between two families of systems is further discussed, and a sufficient condition ... 详细信息

关键词： discrete dynamical system prime isolated invariant set extreme maximal isolated invariant set Conley index bifurcation point

Isolation and diversity analysis of heterotrophic bacteria associated with sea anemones

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Acta Oceanologica Sinica 2010年第2期29卷 62-69页

作者： DU Zongjun ZHANG Wanyi XIA Hongjie LU Guoqiang CHEN Guanjun State Key Laboratory of Microbial Technology Shandong University Jinan 250100 China college of Marine science Shandong University at Weihai Weihai 264209 China

A study was undertaken to investigate the heterotrophic bacterial flora associated with the sea anemones. Samples of the sea anemones Anthopleura midori were collected from the coast of Weihai and bacteria were isolated from these samples. Additionally, high numbers of viable bacteria were obtained from the celom wall and surface of anemone, the community of cultivable bacteria was very diverse. As a result of this isolation, 60 strains were obtained, 56 of them were selected for identification and characterization by 16S rRNA gene sequence analysis and limited phenotypic testing. Among these isolates, 16 strains were phylogenetically related to members of the genus Pseudoalteromonas and neighboring taxa. Other isolates included members of the genera Colwcllia, Vibrio, Acinetobactcr, Pseudomonas, Endozoicomonas, Roseovarius, Paraeoceus, Loktanella, Leisingcra, Sulfitobacter, Bacillus, Staphylococcus, Plantibacter, Microbaeterium, Micro- coccus, Joostella, Psychroserpens, Cellulophaga, Krokinobaeter, Polaribacter and Psychrobaeter. Seven potential novel species were found. Among 60 strains, 17 of them can produce proteolytic exoenzyme, 20 can produce lipolytic exoenzyme. Strain NQ8 has strong antagonistic effects on some Vibrio strains. This study demonstrates that the culturable fraction of bacteria from the sea anemones Anthopleura midori is diverse and appears to possess much potential as a source for the discovery of novel bioactive materials.

关键词： Anthopleura midori Bacterial diversity 16S rRNA gene Phylogeny Identification

Estimation of genetic parameters and breeding values in shrimp F enneropenaeus chinensis using the REML/BLUP procedure

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Acta Oceanologica Sinica 2011年第1期30卷 78-86页

作者： ZHANG Tianshi KONG Jie LUAN Sheng WANG Qingyin LUO Kun TIAN Yia college of life sciences and Technology Ocean University of China Qingdao 266003 China Key Laboratory for Sustainable Utilization of Marine Fisheries Resources Ministry ofAgriculture Yellow Sea Fisheries Research Institute Chinese Academy of Fishery SciencesQingdao 266071 China Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China

An analysis of a selection experiment was used to assess the impact of various animal model struc- tures on REML estimates of variance components. The analyses were carried out based on 162 d body mass （BM） of 1 287 animals from 21 paternal half-sib groups of Fenneropenaeus chinensis. Estimated breeding values （EBV） of BM of all individuals were estimated using eight statistical models （A, AB, ABC, ABDC, ABMFC, ABMDC, ABFDC and ABMFDC） and BLUP （best linear unbiased prediction）. These models were designed involving factors such as sex, spawn date as fixed effects, maternal genetic effects, full-sib family effects as random effects, mean BM of families at tagging and age at recording （covariate）. The results demonstrate the importance of correct interpretation of effects in the data set, particularly those that can influence resemblance between relatives. The data structure and the particular model that was applied markedly influenced the magnitude of variance component estimates. Models based on few effects obtained upward biased estimates of additive genetic variance. The accuracy of genetic parameters and breeding value es- timated by ABFDC model was higher than other models. The results imply that additive genetic direct value, full-sib family effects, and covariance effects besides sex and spawn date as fixed effects were very important for estimating genetic parameters and breeding value of body mass. This model had a heritability estimate of 162 d BM of 0.44. The comparison of the efficiency of selection based on breeding values or phenotypic value revealed great difference： average breeding value of the best 24 families selected by the 162 d BM breeding value and phenotype were 0.577 g and 0.366 g, respectively, representing a 36.57% higher efficiency in the former. In conclusion, selection based on breeding value was more effective than selection based on phenotypic value. Our results indicate that effects influencing the magnitude of estimates should be tak

关键词： Fenneropenaeus chinensis animal model BLUP breeding value

Wireless Networked Control Systems with GPC and New Smith Predictor

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Wireless Networked Control Systems with GPC and New Smith Pr...

2010 Chinese Control and Decision Conference

作者： Feng Du,Wencai Du,Yukuan Du,Baodan Chen college of Information sciences & Technology,hainan university,haikou 570228

＜正＞Wireless network delay is the main factor that deteriorates the performance of the wireless networked control systems（WNCS）.In order to effectively restrain the impact of network delay,a new approach is proposed that novel Smith predictor combined with generalized predictive control（GPC） for the *** novel Smith predictor hides predictor models of the network delays into real network data transmission processes,further the network delay no longer need to be measured,identified or estimated *** this new Smith predictor doesn’t include the prediction model of the controlled plant,thus it doesn’t need to know the exact mathematical model of the controlled *** is applicable to some occasions that network delay is random,time-variant or uncertain,and there are some data dropouts in closed *** on IEEE 802.11b/g（WLAN）,the results of simulation show that this approach is effective.

关键词： Generalized predictive control Wireless networked control systems Network delay Smith predictor

Wavelet Transform for Predicting Apoptosis Proteins Subcellular Location

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Wuhan university Journal of Natural sciences 2010年第2期15卷 103-108页

作者： SONG Chaohong, SHI Feng college of science, Huazhong Agricultural university, Wuhan430070, Hubei, china college of science Huazhong Agricultural University Wuhan China

Apoptosis proteins have a central role in the develop- ment and homeostasis of an organism, and their function is related to their types. In this paper, we constructed the character vectors of apoptosis proteins from their amino acid sequences by using the discrete wavelet transform, combined with support vector machine, to predict the type of given apoptosis proteins. For the widely used dataset z98, high success rates were obtained by Jackknife test, and the Matthews correlation coefficients were 0.92, 0.90, 0.81 and 0.80, respectively, which were higher than the other methods on average.

关键词： wavelet transform support vector machine subcellular location

Efficient expression of codon-adapted human acetaldehyde dehydrogenase 2 cDNA with 6×His tag in Pichia pastoris

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science china(life sciences) 2009年第10期52卷 935-941页

作者： ZHAO YuFeng1,2, LEI MingKe2, WU YuanXin2, ZHANG ZiSheng3 & WANG CunWen2 1 State key Laboratory of Agricultural Microbiology, college of life science and Technology, Huazhong agriculture university, Wuhan 430070, china 2 Key Laboratory for Green Chemical Processes of the Ministry of Education, Hubei Key Lab of Novel Reactor & Green Chemical Technology, School of Chemical Engineering and Pharmacy, Wuhan Institute of Technology, Wuhan 430074, china 3 Department of Chemical Engineering, university of Ottawa, Ottawa, Canada K1N 6N5 1. State key Laboratory of Agricultural Microbiology College of Life Science and Technology Huazhong Agriculture University Wuhan 430070 China 2. Key Laboratory for Green Chemical Processes of the Ministry of Education Hubei Key Lab of Novel Reactor & Green Chemical Technology School of Chemical Engineering and Pharmacy Wuhan Institute of Technology Wuhan 430074 China 3. Department of Chemical Engineering University of Ottawa Ottawa Canada K1N 6N5

Human mitochondrial acetaldehyde dehydrogenase 2 (ALDH2) catalyzes the oxidation of acetaldehyde to acetic acid. Therefore, ALDH2 has therapeutic potential in detoxification of acetaldehyde. Further-more, ALDH2 catalyzes nitroglycerin to nitrate and 1, 2-glyceryldinitrate during therapy for angina pectoris, myocardial infarction, and heart failure. Large quantities of ALDH2 will be needed for potential clinical practice. In this study, Pichia pastoris was used as a platform for expression of human ALDH2. Based on the ALDH2*1 cDNA sequence, we designed ALDH2 cDNA by choosing the P. pastoris preferred codons and by decreasing the G + C content level. The sequence was synthesized using the overlap extension PCR method. The cDNA and 6×His tags were subcloned into the plasmid pPIC9K. The recombinant protein was expressed in P. pastoris GS115 and purified using Ni2+-Sepharose affinity chromatography. The amount of secreted protein in the culture was 80 mg/L in shake-flask cultivation and 260 mg/L in high-density bioreactor fermentation. Secreted ALDH2 was easily purified from the culture supernatant by using Ni2+-Sepharose affinity chromatography. After purification of the fermentation supernatant, the enzyme had a specific activity of 1.2 U/mg protein. The yield was about 16 mg/L in a shake flask culture of P. pastoris GS115 which contained the original human ALDH2*1 cDNA.

关键词： acetaldehyde dehydrogenase codon optimization overlap extension PCR Pichia pastoris.

Cadmium and Zinc Accumulation in Maize Grain as Affected by Cultivars and Chemical Fixation Amendments

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Pedosphere 2011年第5期21卷 650-656页

作者： GUO Xiao-Fang WEI Ze-Bin WU Qi-Tang QIU Jin-Rong ZHOU Jian-Li Key Laboratory of Ecological agriculture of Ministry of agriculture of china College of Natural Resources and Environ- ment South China Agricultural University Guangzhou 510642 (China) South china Institute of Environmental sciences Ministry of Environmental Protection Guangzhou 510655 (China) college of agriculture Yangtze University Jingzhou 434025(China)

A field experiment was conducted to investigate the effects of soil amendments(lime,nano-Si foliar solution and used diatomite) on the growth and metal uptake of three maize(Zea mays L.) cultivars grown in a Cd and Zn-contaminated acidic *** addition of lime significantly increased the maize grain yields and decreased the concentrations of Zn and Cd in the grains and shoots of maize when compared with the *** the three maize cultivars,Yunshi-5 accumulated the lowest amounts of Cd and Zn in the *** concentrations of Zn and Cd in the grain of Yunshi-5 conformed to the Chinese feed *** data revealed that a combination of low metal-accumulating maize and chemical fixation could effectively provide a barrier to prevent metals from entering the human food chain.

关键词： grain yield heavy metal low metal-accumulating cultivar Zea mays L.

Some Practice and Ideas on Education Reform of Numerical Analysis Course

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Some Practice and Ideas on Education Reform of Numerical Ana...

2010 The 2nd International Conference on Industrial Mechatronics and Automation (ICIMA 2010)

作者： Dianxuan Gong Aimin Yang Ling Wang college of science Hebei Polytechnic university Tangshan Hebei 063009 china Chuanan Wei Department of Information Technology hainan Medical college haikou hainan 571101 china

As a required course in polytechnic schools,"Numerical Analysis" is the bridge between the practical application and mathematic *** on the course features and some problems encountered in the teaching process,we carried out some research on education reforms,and put forward some ideas on teaching content and teaching *** these achieved good results in teaching practice.

关键词： Numerical Analysis Scientific Computing Teaching Methods Teaching Mode

Syntactic Dependency for Relation Extraction from Biomedical Literature

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Syntactic Dependency for Relation Extraction from Biomedical...

2012 National Conference on Information Technology and Computer science

作者： Xiaomei Wei college of science Huazhong agriculture university Wuhan,china Jianyong Wang college of science Huazhong agriculture university Wuhan,china Yang Li college of science Huazhong agriculture university Wuhan,china

Relation extraction is important to improve complex natural language processing （NLP） *** Bio-Event extraction in GE shared task is important to understand biological *** some progress has made in GE research,there is still much work to do to improve the performance of the extraction *** this paper,we build a extraction system based on syntactic dependency *** on the output of the sentence parsing,we get rich features to build a classification model to separate the candidate edges into positive class and negative *** obtain promising results on GE develop data *** the results of simple events are comparable with the state-of-the-art GE extraction systems.

关键词： syntactic parsing Dependency Classification extraction.