Genome-wide association study of leaf architecture in the maize nested association mapping population

US maize yield has increased eight-fold in the past 80 years, with half of the gain attributed to selection by breeders. During this time, changes in maize leaf angle and size have altered plant architecture, allowing more efficient light capture as planting density has increased. Through a genome-wide association study (GWAS) of the maize nested association mapping panel, we determined the genetic basis of important leaf architecture traits and identified some of the key genes. Overall, we demonstrate that the genetic architecture of the leaf traits is dominated by small effects, with little epistasis, environmental interaction or pleiotropy. In particular, GWAS results show that variations at the liguleless genes have contributed to more upright leaves. These results demonstrate that the use of GWAS with specially designed mapping populations is effective in uncovering the basis of key agronomic traits.     

五味子有效成分保护心室重构的研究进展

五味子对心血管、免疫系统及CNS具有调节作用,阐述了五味子中有效成分木脂素和多糖保护心室重构的作用.     

Preparation of rare-earth-modified medical stone powders and their application as conductive fillers

Traditional metal conductive fillers are expensive and prone to oxidation. Thus, the development of new conductive powders as fillers is urgently needed. A novel gaseous penetration technology was adopted to prepare La-doped medical stone powders(La-MSPs), which are inexpensive mesoporous materials, as a new kind of conductive filler material. The prepared La-MSPs attained a resistivity of 450 ?·m and were used as a filler to prepare conductive coatings with epoxy resin as the resin matrix. The influence of the La-MSPs dosage on the resistance and hardness of the coatings was also determined. The resistance and the hardness both decreased with increasing filler dosage. Finally, the optimum recipe of the conductive coatings with the most suitable fillers dosage(55 wt%) was obtained. The hardness and resistance of the coatings with 55 wt% La-MSPs were HV 4 and 5.5 × 10~7 ?, respectively.     

WWW服务器与数据库接口的应用研究

本文对Windows NT Internet Information Server与SQL数据库接口技术进行了较深入的分析研究，并应用于贵州大学人事查询系统，介绍了应用程序界面ISAPI（应用程序编程接口），数据库连接器文件（.idc)和HTML扩展名（.htx)文件等。     

重铬酸盐──三醋纤全息记录介质敏化液的最佳配制

本文通过实验研究了重铬酸盐──三醋酸纤维素酯全息记录新材料，敏化液中铬盐的用量，溶液的ｐＨ值及两种电子供体ＤＭＦ、ＤＭＳＯ对全息介质光敏性和全息图实时衍射效率的影响，实验结果表明，在敏化液中选择１５％的重铬酸铵，ｐＨ值取６．５以及电子供体的引入不仅提高了材料的感光记录速度，而且大大提高了全息图的实时衍射效率．     

一种BDCM驱动系统的实验研究

本文提出了一种无刷直流电机驱动系统的ＰＷＭ控制方法，并进行了实验研究，最后给出了实验结果。     

南桐煤矿煤与瓦斯突出区域性预测的定量分析

本文应用模糊相似选择理论对南桐煤矿九个瓦斯地质区的突出危险程度进行了定量分析,得出了其煤与瓦斯突出危险程度的排列次序,与原定性分析的结果相符。     

多台PC微机共享打印机的实现

提出一个采用巡回轮流分配方式的可供8台PC微机共享一台打印机的方案,介绍了实现该方案所应用的单片机识别和控制。     

肝素化抗凝血材料的键合方式与肝素释放速率间的关系

通过对3种不同键合类型的肝素化材料及其肝素释放速率的研究指出Tanzawa临界释放速率理论的局限性。对于肝素化材料,一定量肝素的释放并非其具备抗凝血性能的必备条件,只要肝素的立体构型不发生变化且可自由运动,即具备潜在的抗凝性能。