杉木ClSAUR25基因5'侧翼序列的克隆与生物信息学分析

S4UR(Small auxin-up RNA)基因作为生长素信号早期响应基因,在调控植物生长发育以及对逆境胁迫的应答中扮演着关键角色.本研究通过染色体步移法从杉木基因组DNA中获得了ClSAUR25基因5'侧翼序列,并对其进行了生物信息学分析.结果表明,克隆获得ClSAUR25基因上游5'侧翼序列1 471 bp,该...     

水果高速实时分级机构控制系统

设计了水果实时分级机构，研究了确定水果位置信息并实现同步跟踪的方法，建立了水果在图像中的位置和分级机构分级时的实际位置间的关系，设计了由计算机、位置传感器、通用的数字逻辑芯片、分立电子元器件和步进电机等组成的水果分级控制系统，并进行了试验验证。试验结果表明：控制系统可以对分级机构实现及时、准确的启闭控制，达到了实际分级过程所要求的速度。     

不同砧木嫁接白皮黄瓜的综合效应研究

试验分别以黑子南瓜、荆州南瓜、十堰南瓜、鄂西南瓜、天门葫芦作砧木嫁接白皮黄瓜 ,以自根苗作对照 ,对它们的生长发育情况、产量及抗病性进行了研究。结果表明 ,不同砧木嫁接苗的枯萎病发病率都极显著低于自根苗 ;黑子南瓜、荆州南瓜、十堰南瓜砧嫁接苗生长势始终优于自根苗 ,而鄂西南瓜砧的生长势始终与自根苗的相当。天门葫芦砧嫁接苗生长势前期优于对照 ,后期明显不如对照 ,出现了生理不亲和的特征 ;除鄂西南瓜砧外 ,其它砧木嫁接苗的开花结果比自根苗早 ,且前期产量显著高于自根苗。黑子南瓜、荆州南瓜砧嫁接苗的总产量显著高于自根苗 ,而鄂西南瓜和天门葫芦砧的总产量分别比自根苗的降低了 7 2 %和 2 6 5 %。十堰南瓜砧的总产量与对照差异不显著。从综合效应考虑 ,黑子南瓜、荆州南瓜是白皮黄瓜嫁接的理想砧木 ,十堰南瓜次之 ,鄂西南瓜嫁接效果不好。天门葫芦可作为白皮黄瓜早春大棚栽培的嫁接砧木。     

梳棉内层杂质高光谱图像检测

以梳棉内部深度1 ～6 mm处的多种杂质为研究对象,研究了高光谱成像技术检测效果和可行性.在波长460～900 nm范围内,提取高光谱图像中杂质和棉花的像素光谱.采用二次判别分析分类像素,构造分割二值图像,使用面积过滤器和形态学组合方法剔除二值图像中的噪声点和伪目标,统计杂质检测效果.结果表明可以检测棉网内一定深度的普通杂质(植物性杂质)、彩色丙纶丝、有色线和有色布块,能够检测部分黑色毛发和灰色丙纶丝.其中,普通杂质的检测效果最佳,正确检测率超过80％.     

Radical scavenging conserves from unused fresh green tea leaves

Green teas were made by inactivating the enzymes present in fresh leaves of coarse/pruned (unused) and normal (used for tea) grades using different sources of thermal energies. Green teas were extracted in a Soxhlet using different solvents. The obtained miscella was subjected to concentration to give the extract. The extract was subjected to solvent-solvent extraction. Solvent extract was concentrated to obtain conserve. The yields of conserves are 17 +/- 0.8 and 15 +/- 0.8% from green teas of normal and coarse tea leaves, respectively. The radical scavenging activity of these extracts was evaluated using a DPPH in vitro model system. The total polyphenol content was also determined and found to be higher in conserves from normal tea leaves. However, radical scavenging activity of conserves from coarse and normal green tea leaves was found to be >90% at 15 ppm concentration. The HPLC profiles of these conserves were used to quantify the total catechin content with the help of calibration curves prepared using authentic samples at known concentrations. The total catechin content is found to be in the range of 55-85%. Results indicated that the extracts from coarse leaves also possess potential biological activity and could be used as nutraceuticals as well as for preservation purposes in food formulations.     

维生素D3能降低饲料成本,减少对环境的危害

现在,饲养到42日龄的肉鸡体重一般超过2.4kg,而产蛋鸡在52周的产蛋期内大约能产蛋320个。但是,鸡的遗传潜能发生如此快速变化,致使鸡容易出现几种代谢性的疾病:如腹水症、猝死综合征、骨骼畸形和各不同生长阶段的健康问题。肉鸡的快速生长与其胫骨软组织营养代谢障碍症(TD)密     

广东省自然保护区生态旅游管理研究初探

自然保护区内开展生态旅游,可提高公众的环保意识,增加保护区的经济收入,但也会对保护区的生态平衡和动植物资源造成一定的负面影响.如何处理好自然保护与旅游开发的关系日益引起人们的关注,笔者对国内外开展生态旅游的自然保护区进行了调查分析,认为在自然保护区内开展生态旅游,必须采取切实有效的管理措施,进行科学规划,完善管理制度和监测体系,以达到不破坏生态环境和旅游资源永续利用的目的.     

基于随机森林模型的茶叶消费者粘性影响因素分析

文章从需求频次与消费意愿的影响因素入手,提出了茶叶消费者粘性指数综合评价模型,该模型包括粘性构成要素、影响因素及其具体评价3部分;其中粘性构成要素包括需求频次与消费意愿,影响因素包括感知有用性、可替代性、感知价值、转移成本、专业素养和社会属性,具体评价指标共12项.采用调查问卷收集不同消费者对模型指标的评价数据,并通过...     

植物无融合生殖研究的现状及进展

介绍了植物无融合生殖在选育无融合生殖品种及育种材料方面的成果;概述了植物无融合生殖在胚胎学、遗传学及生殖特性,杂种优势固定途径及无融合生殖材料选育途径等方面研究的现状和趋势。      

Lipids in Wheat Flour Streams

Lipids play an important role in determining the quality of wheat flour and its suitability for different bakery products. The lipid content and fatty acid composition in various flour streams showed a wide variation. The free lipid content varied from 0·1 to 1·9% (db) and bound lipid content from 0·2 to 2·1% (db) in different flour streams. The amount of bound lipid was more in reduction streams. The palmitic and linoleic acids were the predominant fatty acids present in free and bound lipids. These fatty acids were found to be higher in the «III» «Break coarse», «IV» «Break filter», «III» «Break fine», «1st» and «4th» «middling». The studies showed that the reduction passage flours had more of bound lipids indicating the presence of polar lipids.