Protamex酶解玉米蛋白质制备生物活性玉米肽的研究

利用Protamex蛋白酶控制玉米蛋白水解,制备有利于消化吸收,具有降血压和抗氧化等特定生理功能的玉米肽。适度变性的玉米蛋白易被Protamex蛋白酶水解,热处理的时间和温度均影响玉米蛋白的变性程度,经温度85℃热处理60min的玉米蛋白的水解度最大。相同的水解时间,在pH值为9.0,温度60℃时,该酶对变性玉米蛋白的水解度最大,在此条件下酶解60min,消耗NaOH（5mol/L）16.3mL,玉米的水解度为32.5%,肽的得率为51.2%。SephadexG-25对玉米蛋白水解产物的分离结果表明,Protamex蛋白酶水解玉米蛋白可生成分子量不同的5个组分。     

OPTIMAL ACTIVE POWER ADJUSTMEMT OF LARGE HYBRID AC/DC SYSTEMS AFTER OUTAGE CONTINGENCIES WITH THE APPLICATION IN RELIABILITY EVALUATION

An optimal active power adjustment model is deve in this paper for hybrid AC/DC systems after outage contingencies. The objective of the model is to minimize the rejection of load when some elements are out of service, with adjustment strategy approaching practical system operation. A large number of outage contingencies are simulated when the Monte-Carlo Method is emyloyed to evaluate the system reliability, requiring fast calculation of each simulation. The model and computer method proposed in this paper satisfy such a requirment because of the application of concentric relaxation, recursive branch constraint treatment in linear programming and a direct method for B-1 matrix modification. This paper is concerned with the simplified steady state conditions of the system based on DC load-flow, which implies the reliability indices calculated are the measures about static loss of load. The results for a 14-bus hybrid AC/DC system are given.     

The role of sensitivity to abscisic acid and gibberellin in pre-maturity α-amylase formation in wheat grains

To study the role of abscisic acid (ABA) and gibberellin (GA) sensitivity in regulating pre-maturity α-amylase (PMA) in wheat grains, plants were grown in a glasshouse under cold-shock and ambient conditions. α-amylase activity in response to applied ABA and GA was measured in detached-grains with the embryo removed (in vitro) and in intact-grains attached to the plant (in situ). The in vitro experiment was conducted using Spark (low PMA-susceptible genotype) and Rialto (highly PMA-susceptible genotype), with the aim of defining the time point for GA-sensitivity. The results showed an increase in GA-sensitivity at about 640 degree days after anthesis (DAA) in Rialto. There was no evidence for a change in ABA-sensitivity in either variety. The in situ experiments were conducted using genotypes from a Spark × Rialto doubled haploid population segregating for the Rht-D1a (tall) or Rht-D1b allele and for the presence or absence of 1BS/1RS. For Rht-D1a (tall) or Rht-D1b genotypes with or without 1BS/1RS, the cold-shock significantly increased GA-sensitivity, whereas there was no significant change in ABA-sensitivity. These results show PMA is related to an increase in GA-sensitivity that occurs in the aleurone at around 640 degree DAA, and can be enhanced by environmental factors (e.g. cold-shock).     

低分子量有机酸对土壤中铝的化学行为的影响

本文从Al在土壤中的水解-沉淀、吸附-解吸、活化、迁移、降低毒性以及对含Al矿物的表面性质的影响等方面综述了低分子量有机酸对Al的化学行为的影响,并提出了今后需要进一步加强研究的一些方面。     

桑天牛长尾啮小蜂产卵及寄主识别行为的观察与研究

桑天牛长尾啮小蜂(Aprostocetus fukutai)是桑天牛(Apriona germari)卵期寄生蜂,研究其寄生机制对桑天牛的生物防治有重要意义。该寄生蜂的产卵行为主要包括桑天牛刻槽的定向搜寻、刻槽表面的检验、寄主卵检验、产卵寄生、标记等,其中刻槽表面检验的时间较长。选择试验显示,正常刻槽产卵桑枝对寄生蜂的引诱作用明显高于正常桑枝和取食桑枝。在刻槽未产卵桑枝、刻槽产卵未涂抹分泌物桑枝和正常刻槽产卵桑枝中,正常刻槽产卵桑枝对寄生蜂的引诱作用最强,并且刻槽检验时间、寄主卵检验率和寄生率等都显著高于前两个处理。已寄生刻槽对长尾啮小蜂的引诱作用明显低于未寄生刻槽。     

京海黄鸡公鸡性行为的观察研究

采用全天观察法,对京海黄鸡公鸡的性行为进行记录,获得京海黄鸡公鸡性行为的过程,总结京海黄鸡公鸡性行为规律,分析京海黄鸡公鸡个体间性行为的差异,并通过检测精液品质,研究京海黄鸡公鸡性行为与精液质量的关系;通过观察晴天与阴天时的性行为,分析不同的天气对京海黄鸡公鸡性行为的影响,结果显示：京海黄鸡性行为个体间差异不大,受天气的影响较为明显。本文通过对京海黄鸡公鸡性行为的观察研究,为进一步提高京海黄鸡公鸡自然交配的授精率和繁殖性能提供一定的科学依据。     

奶牛健康监测设备与技术研究及应用进展综述

我国的奶牛养殖数量逐年增加,通过对奶牛的生理参数和行为进行监测,可以提高奶牛养殖的经济效益,提升我国奶业的竞争力。随着人工智能技术的发展,奶牛健康监测的设备和技术在不断更新和完善,为奶牛健康监测提供了便捷和精确的手段。本文综述了近年来奶牛健康监测方面的研究进展,从奶牛的生理参数监测和行为监测两方面展开,生理参数包括体温、体尺、体质量、呼吸频率等,行为包括基本行为（站立、行走、躺卧等）、反刍、跛行等。对国内外奶牛健康监测的设备和技术进行了系统的分析,总结了不同监测设备和技术的优缺点和适用情况,并结合当前已有的应用案例,对奶牛健康监测研究所面临的问题进行了讨论,指出了奶牛智慧养殖的发展趋势,旨在为奶牛健康管理和养殖业的可持续发展提供方法和思路的参考。     

网师园的空间景观与环境行为探究

从网师园的历史沿革、造园立意、平面布局、主要景观及空间特色等方面分析了园内环境景观与古代文人雅士的居、息、游、赏,以及现代游览者领略文化、休闲游园等行为活动之间的关系。探究了“因诗成景”、“以画入园”的独特景观营造思想和布局手法及其在有限空间的无限意境中提高人们感知、体验、参与环境的行为价值。最后结合当下的时代精神,提炼了中国古典园林中的景观环境行为理念。     

干旱胁迫下外源物质对番茄幼苗活性氧代谢及光合作用的影响

以番茄品种‘金棚一号’为试验材料,研究不同外源物质(10mmol/L CaCl2、5mmol/L GABA、0.5mmol/L Put、0.5mmol/L Spd)对干旱胁迫下番茄幼苗活性氧代谢及光合作用的影响。结果表明:与对照相比,干旱胁迫处理抑制了番茄幼苗的生长,使幼苗光合系统Ⅱ(PSⅡ)能力降低,叶片可溶性蛋白质含量降低,游离氨基酸及可溶性糖含量升高,活性氧代谢的变化造成MDA积累;外源物质CaCl2、GABA、Put、Spd均可提高幼苗的株高、茎粗、干重和鲜重以及叶片中可溶性蛋白质、游离氨基酸、可溶性糖含量,通过提高抗氧化酶(SOD、POD、CAT)活性,降低了O2.-产生速率、H2O2和MDA含量,维持较高的叶绿素荧光参数Fv/Fm、ΦPSⅡ、qP、ETR,从而在一定程度上缓解干旱胁迫对幼苗的伤害。平均隶属函数分析表明,不同外源物质缓解干旱胁迫的途径不同,外源添加Put处理缓解干旱胁迫的作用主要体现在促进植物生长方面,GABA处理则主要体现在减缓干旱胁迫对叶片光系统Ⅱ和活性氧代谢的伤害,Ca2+处理在增加渗透调节物质含量方面更为明显。