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Can Newton method be surpassed

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Chinese Science Bulletin 1999年第2期44卷 132-134页

作者： Naiyang Deng Zhaozhi Wang china agr univ Beijing 100083 Peoples R China

A local algorithm is proposed for unconstrained optimization problem. Compared with the traditional Newton method with Choleski factorization, this algorithm has the same quadratic convergence. But its computation cos... 详细信息

关键词： Newton method Choleski factorization preconditioned conjugate gradient method.

Grey relation function between local electrical potential and stomatal behavior during light exposure in plants

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Chinese Science Bulletin 1998年第19期43卷 1642-1646页

作者： Qiang Leng Lan Huang Baoguang Hua Chenghou Lou china agr univ Plant Physiol & Biochem Lab Beijing 100094 Peoples R China china agr univ Coll Basic Sci & Technol Beijing 100094 Peoples R China Beijing univ agr Plant Physiol & Biochem Lab Beijing 102206 Peoples R China

The stoma of the plant leaf and the factors that elicit movement of its guard cells are taken as a grey system. Effects of temporary light exposure on local electrical potential of the leaf surface (LEP), on CO 2 and on relative humidity (RH) changes within the leaf chamber were recorded with a multi-channel electronic recorder. The results are analyzed by employing the grey relation function ( ξ ) and grey relation grade ( R ) based on the Grey Theory. The analysis shows that LEP could represent the dominant factor in executing the stomatal movement under the light exposure.

关键词： local electrical potential (LEP) grey relation function grey relation grade stomatal behavior.

Establishment of a genetic transformation system for maize inbred P9-10

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Chinese Science Bulletin 1999年第7期44卷 624-627页

作者： Fengyong Zhou Guoying Wang Youju Xie Hongzhi Cui Sandui Guo Jingruil Dai china agr univ State Key Lab Agrobiotechnol Beijing 100094 Peoples R China china agr univ Coll Plant Sci & Technol Beijing 100094 Peoples R China Chinese Acad agr Sci Ctr Biotechnol Beijing 100081 Peoples R China

It was found that the supplement of 10-4 mol/L AgNO3 in N6 medium enhanced the induction of type Ⅰembryogenic calli from immature embryos of maize inbred P9-10. After high-osmotic treatment, the induced calli was taken as transformation recipient to be bombarded with plasmid pMG6 carrying synthetic Bt gene by PDS-1000/He genegun. A total of 14 resistant calli were obtained after screening subsequently on the mediums with gradually increasing selective pressure. 10 plants were regenerated from the resistant calli on 3 different induction media,and 8 out of the 10 regenerated plants were confirmed to be integrated with Bt gene by PCR and Southern blotting analysis. Results of ELISA showed that the Bt-protein content in the leaves of the transgenic plants varied between 20—200 ng/g fresh weight.

关键词： maize inbred genetic transformation Bt gene.

Influence of high voltage static electric field on ultra-weak chemiluminescence of sheep semen

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Chinese Science Bulletin 1998年第4期43卷 305-308页

作者： Huang Zhenyong Gao Shaorong Zhang Zhongcheng china agr univ Coll Anim Sci & Technol Beijing 100094 Peoples R China

Ultra_weak chemiluminescence sent forth by animals’ organs, tissures and cell organs is discussed. It is indicated that if the ultra_weak chemiluminescence of an animal is high, its metabolism is exuberant, and its pregnant rate is high. A study of the influence of ligh voltage static electric field on the luminescence of sheep sperm is carried out.

关键词： sheep semen high voltage static electric field ultra_weak chemiluminescence.

Localization of muscarinic acetylcholine receptor in plant guard cells

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Chinese Science Bulletin 2001年第7期46卷 586-588,618页

作者： Fanxia Meng Xin Liu Shuqiu Zhang Chenghou Lou china agr univ Coll Biol Sci Minist Agr Key Lab Plant Physiol & Biochem Beijing 100094 Peoples R China

Acetylcholine (ACh), as an important neuro-transmitter in animals, also plays a significant role in various kinds of physiological functions in plants. But relatively little is known about its receptors in plants. A green fluorescence BODIPY FL-labeled ABT, which is a high affinity ligand of muscarinic acetylcholine receptor (mAChR), was used to localize mAChR in plant guard cells. In Vicia faba L. and Pisum sativum L., mAChR was found both on the plasma membrane of guard cells. mAChR may also be distributed on guard cell chloroplast membrane of Vicia faba L. The evidence that mAChR localizes in the guard cells provides a new possible signal transduction pathway in ACh mediated stomata movement.

关键词： guard cell mAChR fluorescent localization Vicia faba L. Pisum sativum L.

Effects of frost action on soil physical properties of plough pan

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Chinese Science Bulletin 1999年第5期44卷 445-448页

作者： Ximin Deng Jian Wang Wenshan Zhu Duansheng Chen Liping Liu Chinese agr univ Dept Hort Beijing 100094 Peoples R China Chinese agr univ Dept Soil & Water Sci Beijing 100094 Peoples R China Chinese agr univ Dept Agron Beijing 100094 Peoples R China Chinese agr univ Dept Construct Beijing 100094 Peoples R China

Undisturb ed soil cores of loamy clay plough pan were subjected to the treatments of freezing and thawing in laboratory. The effects of frost action on its bulk density, porosity, and hydraulic conductivity were investigated. The results indicate that freezing and thawing significantly reduced the bulk density of plough pan and increased its porosity and hydraulic conductivity. The reduction in the bulk density was closely related to the average daily soil minimum temperature and soil water content.

关键词： plough pan soil physical properties frost action.

The effects of microfilament and microtubule inhibitors and periodic electrical impulses on phloem transport in pea seedling

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Chinese Science Bulletin 1998年第4期43卷 312-314页

作者： Guo Yuhai Hua Baoguang Yu Fengyi Leng Qiang Lou Chenghou china agr univ Plant Physiol & Biochem Lab Beijing 100094 Peoples R China Beijing agr Coll Plant Physiol & Biochem Lab Beijing 102206 Peoples R China

In phloem transport, whether protoplasmic activity participates in assisting sap flow in sieve element_companion cell complex has long been in debate. The present investigation assumed microfilament (MF) and microtubule (MT), the two constituents of the protoplasmic cytoskeleton, as motive force, and employed germinating pea seedling suspended in moist chamber as experimental material: the seed being the source; the elongating root, the sink. 14 C_labeled sucrose was added to the seed as indicator. The amount of sap transported from source to sink was measured by the increase in root elongation. The transport phloem was within the cylinder of the peeled root in the middle. The exposed cylinder was treated with MF inhibitor (cytochalasin B), or microtubule inhibitor (amiphos_methyl). Results showed that the sap influx into the elongating root, and the 14 C activity as well, was reduced by about one half in treatment with cytochalasin B, and much less by amiphos_methyl treatment. Similar effect was shown in electrical impulse treatment, which seems to disrupt the MF and MT configuration.

关键词： phloem transport electrical impulse microfilament microtubule pea seedling.

Identification and role of plasma membrane aquaporin in maize root

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Chinese Science Bulletin 2000年第16期45卷 1493-1496页

作者： Meijun Zhu Xuechen Wang Jia Chen china agr univ Lab Plant Physiol & Biochem Minist Agr Coll Biol Sci Beijing 100094 Peoples R China

Using antiserum against expressed aquaporin fusion protein, GST-RD28, the distribution of aquaporin in the plasma membrane of maize root protoplasts has been examined under confocal laser scanning microscopy by indirect fluorescence staining. Results indicate that there are abundant aquaporins in maize roots, which are distributed in plasma membrane unevenly. Western blotting analysis of total protein solubilized from maize root plasma membrane shows that antiserum against GST-RD28 can cross-react with one protein around 55 ku. Another 28 ku protein can also be detected when the concentration of SDS and DTT in SDS-PAGE sample buffer is increased. The 55 and 28 ku proteins may be dimeric and monomeric of aquaporin respectively. Functional experiments show that aquaporin blocker HgCI2 and aquaporin antiserum can suppress the swelling of maize root protoplasts in hypotonic solution, indicating that aquaporin in plasma membrane of protoplast facilitates rapid transmembrane water flow.

关键词： aquaporin plasma membrane transmembrane water flow maize roots.

Production of transgenic blastocyst of sheep by somatic cell cloning

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Chinese Science Bulletin 2001年第19期46卷 1630-1634,1674页

作者： Xiaorong An Kemian Gou Yongfu Chen china agr univ State Key Lab Agrobiotechnol Beijing 100094 Peoples R China

Five samples from primary cultures of five sheep ovarian granulosa cells were transfected by pEGFP-N1 DNA. Five transgenic positive cell lines, each from one of the five samples above, were used as donor nuclei for somatic nucleus transfer. A total of 352 in vitro matured and enucleated sheep oocytes were fused electrically with transgenic granulosa cells and 329 reconstructed embryos were obtained after activation by Ionomycin/6-DMAP, and these embryos were cultured in SOFaaBSA medium for 7 d. The result shows that 312 embryos (94.8%) had gone through cleavage and among them 63 (19.1%) had developed to the blastocyst stage. Expression of GFP gene was detected in various stages of early embryonic development by sampling randomly. Blastocyst rates given by the four cells treated with 0.5% FCS starvation was 19.6% (55/280) and it had notshown difference significantly (P>0.05) with the result obtained with another cell line that had not gone through serum starvation (16.3%, 8/49). This experiment

关键词： sheep granulosa cell nucleus transfer transgenic blastocyst.