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厦门大学学报（自然科学版） 2002年第S1期41卷 72-73页

作者： XU Shu-xin 1, ZHAO Ji 2, ZHAN Jian-ming 1, LE Guan 1 (1. college of Mechanical Science and Engineering, jilin university, changchun 130022, china 2. Office of Education Administration, jilin university, changchun 130012, Chi na)

Carrying out experiments and researches on tool bre ak age and undercut of work-piece of free-form surface by using wavelet analysis, both the fault features can be extracted in a special frequency segment of wave let decompose. According to the feature of transient fault, the author proposes for the first time the automatic determination technology of the threshold by us e of the adaptive filter characteristic of wavelet transform. Based on profound researches on steady fault feature, this dissertation makes an effective token o f steady fault feature by using wavelet energy method, and proposes the new idea to identify cut-in case and cut-out case, thereby successfully gives an uniqu e description quantitatively on the characterization of the variation of fault a nd cutting condition in the monitoring system.

关键词： wavelet analysis free-form surfaces CNC mach ining monitoring system

Insulin-like growth factor 2 as a candidate gene influencing growth and carcass traits and its bialleleic expression in chicken

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Science china(Life Sciences) 2005年第2期48卷 187-194页

作者： WANG Genyu1,YAN Bingxue1,DENG Xuemei2,LI Changlü2,HU Xiaoxiang1 & Li Ning1 1.State Key Laboratory for Agrobiotechnology,china agricultural university,Beijing 100094,china 2.Department of Animal Genetics and Breeding,college of Animal Science and Technology,china agricultural university,Beijing 100094,china State Key Laboratory for Agrobiotechnology China Agricultural University Beijing China Department of Animal Genetics and Breeding College of Animal Science and Technology China Agricultural University Beijing China

We have identified DNA polymorphisms in the gene of insulin-like growth factor 2 by PCR-SSCP in a resource population, which was generated by Silky reciprocally crossing to Broilers. A C→G mutation was detected in the exon 2 (at position 71) by sequencing. This single nucleotide polymorphism (SNP) was found to be associated with production traits. Chicken with BB genotype showed more chest angle width but less 3 week body weight and glandular stom- ach weight than chicken with AA genotype (P2 locus was imprinting. Progeny from heterozygote × homozygote reciprocal cross was assayed for ex- pression after the genotype was determined. The transcription of IGF2 was detected by RT-PCR-SSCP. IGF2 gene was expressed bialleleically in 1-day-old neonatal liver and 90-day-old liver, kidney, heart, and muscle of both heterozygote AB and BA chickens. Therefore, IGF2 was not an imprinting gene in chicken. The different genetic effects between the het- erozygote AB and BA remain to be elucidated.

关键词： chicken, IGF2, single nucleotide polymorphism, genome imprinting.

Structural components of the nuclear body in nuclei of Allium cepa cells

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Cell Research 2001年第1期11卷 68-73页

作者： TAO WEI, CHANG HUI YAN, TAO CAI, SHUI HAO, ZHONG HE ZHAI (college of Life Sciences, Peking university, Beijing 100871, china) (Institute of Genetics and Cytology, Northeast Normal university, changchun jilin 130024, china) college of Life Sciences Peking University Beijing China Institute of Genetics and Cytology Northeast Normal University Changchun Jilin China

Nuclear bodies have long been noted in interphase nuclei of plant cells, but their structural component, origin and fUnction are still unclear by now. The present work showed in onion cells the nuclear bodies appeared as a spherical structure about 0.3 to 0.8 μm in diameter. They possibly were formed in nucleolus and subsequently released, and entered into nucleoplasm. Observation through cytochemical staining method at the ultrastructural level codeined that nuclear bodies consisted of ribonucleoproteins (RNPs) and silver-stainable proteins. Immunocytochemical results revealed that nuclear bodies contained no DNA and ribosomal gene transcription factor (UBF). Based on these data, we suggested that nuclear bodies are not related to the ribosome or other gene transcription activities, instead they may act as subnuclear structures for RNPs transport from nucleolus to cytoplasm, and may also be involved in splicing of pre-mRNAs.

关键词： Nuclear body structural component ribonucleoproteins nucleolus Allium cepa.

On-line Preconcentration and Determination of Trace Metals in Water Samples by Flow Injection Combined with Flame Atomic Absorption Spectrometry via Calix[4]arene Carboxylic Acid Packed Micro-column

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Chemical Research in Chinese Universities 2012年第1期28卷 26-30页

作者： GUO Da-wang, ZHAO Xiao-wei, JIA Qiong and ZHOU Wei-hong college of Chemistry, jilin university, changchun 130012, P. R. china college of Chemistry Jilin University Changchun 130012

An adsorbent calix[4]arene carboxylic acid was employed as the adsorption material for on-line flow in jection（FI） micro-column preconcentration coupled with flame atomic absorption spectrometry（FAAS） determination of trace heavy metals（Cu, Pb, Co, Ni and Cd）. Parameters such as the pH, loading time and flow rate of sample, and the concentration, volume and flow rate of eluent were optimized. The enrichment factors are 50.0, 56.5, 11.6, 12.1 and 19.1 for Cu, Pb, Co, Ni, and Cd, respectively, and a sample throughput of 20 h–1 was obtained. The limits of de tection for Cu, Pb, Co, Ni, and Cd were in a range of 1.56―3.91 μg/L, and the relative standard deviations（RSDs） were less than 2.76%（n=7）. Furthermore, the proposed method was successfully applied to the determination of Cu, Pb, Co, Ni, and Cd in certified reference materials and various water samples.

关键词： Calixarene carboxylic acid Preconcentration Flow injection Metal ion Flame atomic absorptionspectrometry(FAAS)

A PSTAIRE CDK-like protein localizes in nuclei and cytoplasm of Physarum polycephalum and functions in the mitosis

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Cell Research 2004年第2期14卷 169-175页

作者： Gui Ying LI~(1,2), Miao XING~(1,*), Bo HU~(1,3) ~1college of Life Science, Shenzhen Key Laboratory of Microbial Gene Engineering, Shenzhen university, Shenzhen 518060, china. ~2Department of Immunology, School of Basic Medical Sciences, jilin university, changchun 130021, china ~3Institute of Genetics and Cytology, Northeast Normal university, changchun 130024, china. college of Life Science Shenzhen Key Laboratory of Microbial Gene Engineering Shenzhen University Shenzhen China Department of Immunology School of Basic Medical Sciences Jilin University Changchun China Institute of Genetics and Cytology Northeast Normal University Changchun China

CDKs play key roles in controlling cell cycle progression in all eukaryotes. In plants, multiple CDKs are present, among which the best characterized CDKs are PSTAIRE CDKs. In this study, we carried out Western blot, immunoelectron microscopy and antibody treatment with an anti-PSTAIRE monoclonal antibody to explore the subcellular localization and functions of PSTAIRE CDKs in Physarum polycephalum. The results of Western blot and immunoelectron microscopy showed that in P. polycephalum, a PSTAIRE CDK-like protein was 34 kD in molecular weight and located in both nuclei and cytoplasm. In nuclei, the protein was mainly associated with chromosomes and nucleoli. The expression of the PSTAIRE CDK-like protein in both the plasmodia and nuclei showed little fluctuation through the whole cell cycle. When treated with an anti-PSTAIRE monoclonal antibody at early S phase, the cells were arrested in S phase, and the mitotic onset of P. polycephalum was blocked for about 1 h when treated at early G2 phase. Our dat

关键词： PSTAIRE CDK-like protein Physarum polycephalum mitosis immunoelectron microscopy.

APPLYING PPE MODEL BASED ON RAGA TO CLASSIFYAND EVALUATE SOIL GRADE

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Chinese Geographical Science 2002年第2期12卷 136-141页

作者： FU Qiang1,2, LU Tie guang2, FU Hong2(1. college of Hydraulic Power, Sichuan university, Chengdu 610065, P.R.china 2. Northeast agricultural university, Harbin 150030, P. R. china) college of Hydraulic Power Sichuan University Chengdu P. R. China Northeast agricultural university Harbin P. R. China

The research of soil classification and soil grade evaluation is often based on fuzzy theory. So, the traditional method has an inevitable problem about weight matrix which given by some experts, and the final result can be influenced by artificial factors. The essentials of fuzzy synthetically judge is to handle the data of high dimension. That is to reducing the dimension number. The weight matrix in fuzzy theory is corresponding to low dimension projection value of each index. But we can′t define whether the weight matrix given by experts is the best projection value or not. So, the authors apply a new technique of falling dimension named projection pursuit to soil study, through using the improved real coding based accelerating genetic algorithm to optimize the projection direction. Thus, it can transfer multi dimension data into one dimension data, through searching for the optimum projection direction to realize the soil classification and its grade evaluation. The method can avoid the artificial disturbance, and acquire preferably effect. Thus, the paper provides a new method to the research of soil classification and grade evaluation.

关键词： RAGA PPE soil classification soil evaluation

Comparative Transcriptome Analysis of Leymus chinensis Under the Saline-alkaline Treatment Based on 454 Pyrosequencing

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Comparative Transcriptome Analysis of Leymus chinensis Under...

Structures and stability of isomers of[Si,N,N,P]system

第十二届全国植物基因组学大会

作者： Yepeng Sun~1,Yuanyuan Dong~2,Nan Wang~2,Haiyan Li~(1*) 1.college of Life Science,jilin agricultural university,changchun,jilin 130118,china 2.Ministry of Education Engineering Research Center of Bioreactor and Pharmaceutical Development,jilin agricultural university,changchun,jilin 130118,china

Leymus chinensis(Trin.) *** a saline-alkaline tolerant forage grass genus,which plays an important role in protection of natural *** date,little is known about the stress tolerance of *** at the molecular *** this study,we used Roche-454 massive parallel pyrosequencing technology to sequence two different cDNA libraries that were built from the two samples of control and under saline-alkaline treatment.A total of 363,734 in control group and 526,266 reads in treatment group with average length of 489bp and 493bp were obtained,*** reads assembled into 104,106 unigenes using MIRA sequence assemble software,among which,73,665 unigenes in control group,88,016 unigenes in

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Science china Chemistry 2004年第2期47卷 98-105页

作者： KAN Wei1, YU Haitao1, LI Mingxia1, FU Honggang1,2 & SUN Jiazhong1,2 1. college of Chemistry and Chemical Engineering, Heilongjiang university, Harbin 150080, china 2. State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, jilin university, changchun 130023, china college of Chemistry and Chemical Engineering Heilongjiang University Harbin China State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun China

Some stationary points on the potential energy surface of [Si, N, N, P] system were located at the B3LYP/6-311G(d) and QCISD(t)/6-311+G(2df)(single-point) levels of theory, while the isomerization, structures, and stability of these obtained isomers were suggested. The computed results indicate that only four-membered ring isomer SiNPN(E1, 2A'), which possesses butterfly-like structure and Si-P cross bonding, is kinetically stable in all optimized isomers. Other isomers may be considered as kinetically unstable towards isomerization or dissociation because of the corresponding smaller reaction barriers. Furthermore, the present paper also proposes electronic and geometric structures, vibrational frequencies and the corresponding vibrational modes, dipole moments, and rotational constants of isomer E1. To make use of the computed results, we can clearly know that the reaction pathway via an intermediate E3 (SiNPN) is the most favorable channel producing isomer E1 from fragments SiN(2Π) and PN (1Σ), which have been well characterized in space, and thus, isomer E1 can be considered as a candidate for interstellar observation. The reaction enthalpy of SiN(2Π) + PN(1Σ)→ E1 and the standard enthalpy of formation of isomer E1 are 215.25 and 457.99 kJ/mol, respectively, at 298.15 K. Keywords potential energy surface - [Si,N,N,P] system - isomerization - kinetic stability

关键词： potential energy surface, [Si,N,N,P] system, isomerization, kinetic stability.

Multi-objective dynamic detection of seeds based on machine vision

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Progress in Natural Science:Materials International 2007年第2期17卷 217-221页

作者： XUN Yi, ZHANG Junxiong, LI Wei and CAI Weiguo ( college of Engineering, china agricultural university, Beijing 100083, china college of Science, Dalian Fisheries university, Dalian 116023, china) college of Engineering China Agricultural University Beijing 100083 China college of Sciences Dalian Fisheries University Dalian 116023 China

An approach to inspecting massive numbers of moving seeds was studied based on the techniques of dynamic inspection and machine vision. A progressive scanning CCD camera with external trigger function was used for real-time capture of dynamic images of seeds. The methods based on R channel of RGB (Red, Green and Blue) and region-dependent segmentation were adopted to reduce the data size of image processing and improve the efficiency of seeds inspection. All the seeds were sorted into four grades according to their morphological characteristics, such as surface area, perimeter, major axis, minor axis, circularity and eccentricity. The detection experiments indicated that the eligible ratio of the classifications was about 81.90% by this real-time inspection system.

关键词： machine vision seed sorting multi-objective morphological parameter.