基于MATLAB的数字信号基带传输系统仿真

SIMULINK是MATLAB中动态系统建模、仿真和分析的一个集成环境 ,文中按照仿真过程基本步骤用MATLAB的仿真工具SIMULINK实现了数字信号基带传输系统的仿真过程 ,对系统性能进行了分析     

Changes of Plasma Membrane H~+-ATPase Activities of Glycine max Seeds by PEG Treatment

The soybean (Glycine max) Heihe No. 23 is sensitive to imbibitional chilling injury. Polyethylene glycol (PEG) treatment can improve chilling tolerance of soybean seeds to a certain extent. The changes of hydrolytic ATPase in plasma membranes and H+-pumping responses in soybean seeds were investigated during PEG treatments. Effects of exogenous calcium and exogenous ABA on the hydrolytic ATPase were also examined in order to understand the mechanism of chilling resistance. Highly purified plasma membranes were isolated by 6.0% aqueous two-phase partitioning from soybean seeds, as judged by the sensitivity of hydrolytic ATPase to sodium vanadate. PEG treatment resulted in a slight increase of the hydrolytic ATPase activity in 12 h. Then the activity decreased gradually, but still higher than the control. The H+-pumping activity increased steadily during PEG treatment. Exogenous calcium had both activating and inhibiting effects on the hydrolytic ATPase, but the activity was inhibited in soybean seeds treated with exogenous ABA. Results suggested that PEG treatment, not the exogenous calcium and ABA, up-regulated H+-ATPase activities in soybean seeds.     

一种基于最小二乘的心电信号基线矫正方法

从基线矫正的样条函数拟合方法出发,提出了一种基于最小二乘法的基线矫正方法.实验表明,该方法快速、有效、简单,具有可操作性.     

柞蚕抗病机制及其抗病物质的研究——Ⅲ.柞蚕诱导抗菌物质活性与柞蚕对NPV感染抵抗性的相关关系

本试验利用半蛾区测定方法,将同蛾区蛹期诱导抗菌物质活性、稚蚕期对柞蚕NPV的感染抵抗性进行了相关性的比较试验.初步结果表明:(1)同蛾区稚蚕期对NPV感染抵抗性强的.蛹期诱导抗菌物质活性也高,呈正相关关系,(2)蛹期诱导抗菌物质活性高的峨区,次代稚蚕期抗毒力(NPV)也强,呈正相关;(3)柞蚕五龄幼虫经大肠杆菌诱导后也能产生抗菌物质,且其诱导抗菌物质活性与溶菌酶活性趋于正相关.同时,供试的三个柞蚕品种,蚕期和蛹期诱导抗菌物质活性趋于一致.     

复杂非线性电阻电路小信号分析法的研究

利用小信号分析法，对复杂线性电阻网络与数个非线性电阻元件联接的电路进行了分析求解，进而得出了复杂非线性电阻电路的一般分析方法。     

外源总DNA导入培育大豆新品系D89—9822及其育种价值初探

以栽培大豆品系６２９６－３为受体、半野生大豆龙７９－３４３３－１为供体，采用外源ＤＮＡ导入的方法培育成功Ｄ８９－９８２２。该品系具有高产、品质优良、抗病性强等特点，产量比受体增产４４．９％，比标准品种增产１０．５％。蛋白质含量７年（１９８９－１９９５）平均较受体增长近２个百分点，球蛋白总量较受体提高近１０个百分点，并使其与大豆加工品质密切相关的１１Ｓ球蛋白组分所占比例超过７０％。１９９６年参加生产     

Endogenous plant growth substances content in young fruits of seeded and seedless Clementine mandarin as related to fruit set and development

The content of plant growth substances in the fruits of seedless (‘Fino’) and seeded (‘Monreal’) Clementine mandarin (Citrus reticulata Blanco) during the early stages of development was investigated. Auxin-like substances were determined with the oat mesocotyl bioassay, gibberellin-like substances with the α-amylase bioassay, and abscisic acid (ABA) by gas chromatography—electron capture detector. Methanolic extracts of fruits of seedless Clementine had higher content of auxin-like compounds in the acidic and butanolic fractions than the seeded Clementine extracts. In particular, a compound with R_f 0–0.25 in the chromatograms may be involved in the parthenocarpic fruit set development of ‘Fino’ Clementine ovaries. Diffusable gibberellin-like compounds (R_f 0.8–1.0), probably produced in the developing seeds, were obtained from seeded Clementine fruits after the time of anthesis. The content of ABA in the fruits was always low in ‘Monreal’ Clementine, whereas in fruits of ‘Fino’ Clementine and of ‘Monreal’ without seeds it increased dramatically after anthesis. It is suggested that the control of fruit set and development in Clementine mandarin is carried out through an equilibrium between auxin-like substances (‘Fino’) or gibberellin-like substances (‘Monreal’) and ABA.     

Antifungal substances produced by fungal strain Kyu-W63 from wheat leaf and its taxonomic position

Fungal strain Kyu-W63 from a wheat leaf suppressed the development of wheat powdery mildew caused by Blumeria graminis f. sp. tritici. Nuclear magnetic resonance analysis revealed that Kyu-W63 produced two volatile substances: 5-pentyl-2-furaldehyde and 5-(4-pentenyl)-2-furaldehyde. Although the two are known to be nematicidal substances, the antifungal activity of 5-(4-pentenyl)-2-furaldehyde was first confirmed in the present study. Culture experiments revealed that synthesized 5-pentyl-2-furaldehyde had antifungal activity against three other pathogens – Fusarium oxysporum f. sp. lycopersici, Colletotrichum fragariae, Botrytis cinerea – with a minimum inhibitory concentration of 2–4µg/ml. The two fractionated substances were also inhibitory against C. fragariae. Because the absence of spores in strain Kyu-W63 made its identification difficult, the sequence in the rDNA internal transcribed spacer (ITS) region of Kyu-W63 was compared with that of Irpex lacteus, which is known to produce these substances. Strain Kyu-W63 completely agreed with I. lacteus in terms of the ITS sequences, so strain Kyu-W63 was inferred to be I. lacteus. Two other strains of I. lacteus tested also produced the two furaldehydes and suppressed the growth of F. oxysporum f. sp. lycopersici. Both Kyu-W63 and additional strains produced the two furaldehydes on potato dextrose agar but not on water agar.The nucleotide sequence data reported are available in the DDBJ databases under accession numbers AB079264, AB079265, AB079266, and AB079267     

亚低温与干旱胁迫对番茄幼苗渗透调节物质与抗氧化酶活性的影响

以"金棚1号"番茄为试材,采用温室盆栽的方法研究亚低温与干旱胁迫对番茄幼苗渗透调节物质与抗氧化酶活性的影响。结果表明,随着亚低温干旱交互胁迫时间的延长,番茄幼苗叶片MDA含量、细胞膜相对透性均有不同程度的升高,可溶性蛋白含量、SOD活性变化趋势出现先升后降,POD活性呈现倒"V"型变化,CAT活性呈现"M"型变化,番茄幼苗叶片对亚低温胁迫的敏感程度大于干旱胁迫的影响。相关性分析与主成分分析显示:POD、CAT活性与细胞膜相对透性呈极显著负相关,与MDA含量呈显著负相关;SOD活性与MDA含量呈正相关,POD与CAT活性呈显著正相关。     

烟草早花生理与分子机理的研究进展

概述了烟草早花的诱导途径、早花生理信号及成花基因的诱导和表达等。