皮埃蒙特杂种肉牛生长激素基因型与体重、日增重的相关性研究

本研究利用PCR-RFLPs标记技术，对63头杂种肉牛的生长激素基因的第5外显子和3’端区域进行了分析寿终正寝分现HaeⅢ酶切位点具有多态性，并分为三种基因型（AA、BB和AB）。通过构建最小二乘线性模型。分析了生长激素基因型与杂种肉牛高于12月龄体重和6-12月龄日增重的关系。结果表明：生长激素AB基因型的效应稍高于AA、BB型，但差异不显著。     

Effects of soil moisture and sowing depth on the development of bean plants grown in sterile soil infested by <Emphasis Type="Italic">Rhizoctonia solani</Emphasis> and <Emphasis Type="Italic">Trichoderma harzianum</Emphasis>

The effects of soil moisture (varying from 15% to 42% (v/v)) and sowing depth (1.5–6.0 cm) on the development of bean plants grown in sterile soil infested by the pathogen Rhizoctonia solani and its antagonist Trichoderma harzianum were studied under greenhouse conditions. The four possible combinations of soil infestation with both fungi were tested. Disease severity, percentage of plants emerged, plant height and dry weight were evaluated 3 weeks after sowing. Emergence rate and growth of plants inoculated only with R. solani were not affected by soil moisture, but in the presence of both fungi, plant emergence, plant height and dry weight significantly decreased when soil moisture diminished. Deep sowing significantly reduced the emergence rate and growth of those plants that were inoculated with R. solani only. However, when the soil was infested with both fungi, the effect of sowing depth was not significant. At a sowing depth of 6.0 cm, the percentage of plants emerged was 50% in the presence of T. harzianum, but only 6.7% when the pathogen was inoculated alone. The antagonist protected bean seedlings from pre-emergence damping-off, reduced disease severity and increased plant growth in the presence of R. solani, especially in moist soil.     

EXCEL在饲料配方分析中的应用

就EXCEL的分析工具库中的“线性规划”的特点进行了介绍,并就如何利用EXCEL的线性规划来求解最佳饲料配方进行了探讨,同时以实例予以说明。     

On the Research of the Periodicity and Statistical Characteristics by Linear Congruence and Combined Generator

In this paper the author researches the periodicity and statistical characteristics produced by linear congruence and combined generator through numerical value tests, and puts forward a random numeral generator with a long periodicity, a good independence and homogeneity.     

1H NMR-based metabolomics for discrimination of rice from different geographical origins of China

Food frauds related to the mislabeling and mixing of products of inferior quality with those of superior quality are a serious concern nowadays. NMR-based metabolomics has great potential in the authentication of foods for quality assurance and the tracing of fraudulent labeling. The present study was conducted to discriminate rice from geographically different provinces of China. The study reports the potential use of ¹H NMR spectroscopy coupled with PCA and a discriminant analysis method, LDA for metabolomic fingerprinting of Chinese rice. A total of 106 rice samples from nine different provinces of China were analyzed for ¹H NMR-based metabolomics. Both the whole variable analysis (heat map) and the Principal Component Analysis (PCA) showed a clear separation among the samples. Linear Discriminant Analysis (LDA) was conducted to extract the variables majorly responsible for this separation, such as sucrose, fructose, glucose, succinate, polyphenols, trigonelline and asparagine. The discrimination was explained on the basis of variations in latitude, temperature and rainfall in these provinces. The study highlights the application of ¹H NMR for geographical discrimination of rice and its usefulness for consumers while choosing their desired variety of rice.     

正则化半监督判别分析方法

为了克服加权线性判别分析(WLDA)只利用有标签的训练样本而不能反映样本数据流形结构的缺点，提出一种正则化的半监督判别分析方法。首先构建所有样本的近邻图来估计数据的局部流形结构，然后将此作为正则项引入WLDA的准则函数中。该方法避免了类内散度矩阵奇异，同时保持了样本数据的判别结构和几何结构。在ORL和YALE人脸数据库上的实验结果证明了该算法的有效性。     

线性规划在农田改造中的应用

以当前新农村建设中农田改造的投资规划决策为背景,建立一个具有普遍性的线性规划模型,并给出模型的具体应用实例。     

基于遥感技术的滁州市各县森林线性优化配置分析

森林植被作为土地覆盖的重要类型之一,在社会、经济、文化和环境中的地位与其所发挥的生态效应相关,对耕地、园地等水土流失区保护就具有重要意义。文章利用遥感影像和一些数学方法来优化配置森林资源,以2000年、2006年相近的滁州市TM遥感影像作为数据源,利用监督分类法对森林植被进行分类、统计、验证和分析,结合层次分析法和线性规划法对森林植被分布进行优化。结果表明定远县、凤阳县、来安县、天长市各县市森林植被配置不合理,需要各增加476.74km^2、255.41km^2、162.76km^2、263.49km^2,适当增加农田林网建设,这样才有利于各县市农林生态和谐发展。     

基于对偶线性规划模型的影子水价计算

以淠史杭灌区为例,利用线性规划对偶规划理论测算灌区用水的影子价格,并将它们和现行水价作比较,其结果对灌区制定水价有重要的指导意义。     

中国人均食用粮食消费量的时序预测

粮食消费预测是安排粮食生产、调整粮食种植结构、制定粮食安全和农业可持续发展战略的重要理论依据。利用粮食消费量与时间之间的相关关系, 采用SPSS程序包进行筛选, 建立我国人均食用粮食消费的时序预测模型。研究结果表明, 所建立的三个时序预测模型的拟合度等统计指标高度显著, 运用所建模型对所获资料进行的内推预测比较准确, 但外推预测结果因影响因素多, 其准确性有待时间和实际的检验。