异源细胞质对普通小麦花粉育性的影响

本文以中国春小麦细胞核置换到小麦属和山羊草属不同细胞质的同核异质稳定核质杂种为材料,研究了异源细胞质对普通小麦花粉育性及小孢子发育的影响,结果表明;普通小麦中国春的花粉育性不同程度地受到多种异源细胞质的明显影响,其小孢子败育主要发生在四分体时期.     

Narrowing the gap: Practical strategies for increasing whole‐grain consumption

Overcoming consumer confusion and doubt regarding nutrition recommendations is key to communicating the message to increase whole‐grain foods in the diet. Nutrition communicators may do that more successfully by using four tactics to fashion messages about whole grains: (1) present a positive message; (2) keep it short and simple; (3) keep the message practical and flexible; (4) speak with a united voice. The quantitative recommendation to eat at least three servings of whole‐grain foods daily also must be integrated into national nutrition documents, such as Healthy People 2000, Dietary Guidelines for Americans, the Food Guide Pyramid, Nutrition Recommendations for Canadians, and Canada's Food Guide to Healthy Eating, if we are to be truly successful in communicating the need to increase whole‐grain consumption.     

Transformations of (14C-lignin) cell walls of wheat by rumen microorganisms

The lower halves of apical internodes of wheat harvested at the flowering stage were labelled with [U-¹⁴C] phenylalanine (phe) or with [O¹⁴CH₃] sinapic acid (sin). Cell wall residues (CWR) and saponified residues (SR) were incubated in a fermenter simulating the rumen for 7 days with rumen fluid or without microorganisms (controls). PheCWR was labelled in all lignin units (measured as aldehydes from nitrobenzene oxidation), in phenolic acids and slightly in proteins. Labelling of pheSR was more lignin-specific. SinCWR and sinSR were specifically labelled in syringyl units of lignin. The fermentation of CWR resulted in phenylpropane-derived unit losses in the following decreasing order: ferulic acid>p-coumaric acid>syringaldehyde>vanillin>p-hydroxybenzaldehyde. If allowance is made for slight losses in controls, 61, 52, 61 and 63% of the phenylpropanes of pheCWR, sinCWR, pheSR and sinSR, respectively, were transformed into an acid-precipitable fraction, an acid-soluble fraction and ¹⁴CO_2. The comparison of pheCWR and sinCWR degradation showed that syringyl units were solubilised into acid-precipitable molecules to a greater extent than the other lignin units; demethylation of the syringyl units of lignins was also evident from the different productions of ¹⁴CO₂. Alkali-resistant lignins of SR were mainly transformed into acid-precipitable molecules and were weakly degraded. Lignin solubilisation and degradation seem to be governed by different mechanisms which depend on both cell wall structure and rumen microflora.     

The glutenin fraction of wheat protein: The importance of genetic background on its quantity and quality

The influence of high-molecular-weight glutenin subunits on the properties of the gel-protein fraction of glutenin proteins in wheat was determined on 20 varieties grown in the 1989 UK Recommended List trials. Both the presence of subunit 1 (chromosome 1A) and the 1B/1R rye translocation were shown to influence gel-protein weight and breakdown rate during mixing. The gel-protein tests were correlated with CBP (Chorleywood Bread Process) loaf volume, but they did not add anything to the correlation between Glu-1 score and loaf volume. Both gel-protein tests indicated that phenotypic variation could be almost as large as genotypic variation. Breakdown rate was able to detect the abnormal properties of Pastiche (weak) and Fresco (extra-strong) that were not observed using established quality tests such as the sodium dodecylsulphate sedimentation volume.     

基于MODIS温度植被角度指数的农作物估产模型研究

利用MODIS数据,以河北石家庄和邢台地区冬小麦产量估算为例,探讨了综合植被指数与陆表温度的温度植被角度指数在农作物估产中的应用研究.首先,根据冬小麦物候历,计算了冬小麦抽穗期四种参量指数:归一化植被指数(NDVI)、增强型植被指数(EVI)、温度植被角度指数(TVA)和增强型温度植被角度指数(ETVA);其次,将实测的冬小麦产量数据与NDVI、EVI、VTA和EVTA数据进行回归分析,建立模型.结果表明,实测产量数据与这四种指数均具有很好的线性回归关系,相关系数R2均在0.60以上(分别为0.61、0.65、0.68、0.74),其中基于TVA和ETVA的估产模型要好于NDVI和EVI模型.由此可见,综合了MODIS光学反射和辐射信息的TVA/ETVA,能有效应用于实践估产中,并提高预测的准确性.     

He-Ne激光对小麦DNA UV-B损伤修复的影响

研究并分析了He-Ne激光对小麦DNA UV-B损伤修复的影响和机理,以探明激光对UV-B损伤修复的影响途径及机制。结果表明,小麦对增强UV-B辐射损伤具有一定的切除修复能力,切除修复的高峰期发生在UV-B辐射后4～6h内;He-Ne激光主要通过促进小麦的切除修复途径影响小麦对 UV-B损伤的修复,在对损伤DNA的切除及DNA的修复合成两方面均有不同程度的促进作用,其切除高峰期发生在UV-B辐射后4～6h;DNA的修复合成高峰期在辐射后6～7h。     

D-Erythroascorbic Acid in Bakers'Yeast and Effects on Wheat Dough

Extraction of hydrated and freeze-dried bakers’yeast yielded ～ 50 μg erythroascorbic acid (EAA) and 5 μg ascorbic acid (AA)/g dry yeast as determined by HPLC with electrochemical detection. D-EAA (82 ppm based on flour) slightly increased the flow of dough as rest time increased. Gluten isolated from a flour-water dough containing 82 ppm D-EAA or 100 ppm Lcysteine stretched at a faster rate than control gluten. EAA like AA did not change dough development time. Unlike AA, EAA showed neither oxidizing effect on dough and gluten nor improving effects on bread.     

High-Protein Texturized Products of Defatted Soy Flour, Corn Starch and Beef: Shelf-Life, Physical and Sensory Properties

Selected mixes consisting of Bf [high-beef (29%) low-fat (2.96%)], bf [low-beef (20%) low-fat] and BF [high-beef high-fat (5%)] which incorporated raw beef, defatted soy flour, and corn starch were extruded in a single-screw extruder. The products had no flavor additives and trained sensory panelists detected hay-like, beany or grainy flavors. Bf extrudate was more expanded than BF extrudate and rated least hard by the sensory panel, whereas bf extrudate was least susceptible to lipid oxidation. Bf and bf extrudates showed microstruc-tures with large air cells. All three showed advantages of beef and soy flour in amino acid and fatty acid compositions, respectively, and were microbiologically safe during prolonged storage at 37°C.     

我国CATV“十二·五”运行维护工作研究

从我国"十一·五"期间有线电视运维的基本特点出发,对"十二·五"有线电视设备管理、安全播出管理和网络维护管理进行了探讨,并提出关于全国有线电视网络整合完成后"全程全网"的有线运维模式观点。     

软件保护研究及其在Java软件保护中的应用

深入剖析了软件保护的机制,阐述了软件保护的基本思想和基本方法,并根据Java类文件的特点,深入研究了Java的编译原理,Java类文件的格式和Java反编译技术,提出了软件要从整体流程上进行保护的观念,设计并实现了用户信息提取器,序列号生成器与序列号合法性判断函数,总结出了针对Java文件的一套保护流程,探索设计出一个实用的安全性较高的保护算法。