The Management Techniques of Distance Education and Its Implementation

The education modes and contents involved in the management of distance education are first analyzed in the paper, and the preliminary implementation based on CERNET and Internet is followed. The techniques of WWW servers efficient access to database and system security are presented in addition.     

The Design and its Implementation of a MultiMedia Course for Cast Iron Welding

How to develop a multimedia course for cast iron welding is discussed.The course is implemented with a multimedia application development software ToolBook 3.0.     

钾对小麦生长发育、抗旱性和某些生理特性的影响

钾对植物的抗旱性有着密切的关系。我们就不同土壤水分条件下钾肥对小麦的生理效应及其对抗旱性的影响作了初步研究。在缺钾的土壤中,无论是充分供水或干旱,施用钾肥均能促进植株对氮和磷的吸收和运转,提高叶水势、叶片持水力,从而提高土壤水分的利用效率。在生长期间,钾能提高叶片的叶绿素含量,增大叶面积,延长叶的功能期,提     

有效微生物的研究及其应用

介绍了有效微生物的组成、特点、应用及其对家畜的作用机理．     

TaIAA15 genes regulate plant architecture in wheat

Bread wheat (Triticum aestivum L.) is one of the most important staple crops worldwide. The phytohormone auxin plays critical roles in the regulation of plant growth and development. However, only a few auxin-related genes have been genetically demonstrated to be involved in the control of plant architecture in wheat thus far. In this study, we characterized an auxin-related gene in wheat, TaIAA15, and found that its ectopic expression in rice decreased the plant height and increased the leaf angle. Correlation analysis indicated that TaIAA15-3B was associated with plant height (Ph), spike length (SL) and 1 000-grain weight (TGW) in wheat, and Hap-II of TaIAA15-3B was the most favored allele and selected by modern breeding in China. This study sheds light on the role of auxin signaling on wheat plant architecture as well as yield related traits.     

带FR、G端子的三菱发电机电压调节器调压原理分析与检测

对带有FR、G端子的三菱发电机电压调节器调压原理进行了具体分析,同时介绍了FR、G端子的具体就车检测方法。     

美国国家农业研究计划及特点

一、美国国家农业研究计划的主要内容 目前ARS正在组织实施的美国国家农业研究计划属于ARS战略计划2003-2007中的内容.其使命与职责是:通过科学研究发展和转移解决具有高度国家优先权的农业问题的知识、技术和方法,以及提供信息存取和分发;具体包括保证高质量、安全的食品和其他农产品的供应,评定美国人民的营养需要,维持一个具有竞争力的农业经济,提高自然资源的基数和环境质量,将农村公民、团体和社会作为一个整体并为他们提供经济机会.     

The effects of protein kinase A catalytic subunit on sperm motility regulation in Pacific abalone Haliotis discus hannai

Protein kinase A plays a central role in the regulation of sperm motility from echinoderms to mammals, but the information about its regulatory role in molluscs is very limited. In this study, a protein kinase A catalytic subunit (designated as HdPKA‐C) was identified from Pacific abalone Haliotis discus hannai. The open reading frame of HdPKA‐C was of 1,077 bp, encoding a peptide of 358 amino acids with a typical protein kinase domain. HdPKA‐C shared 82%–87% sequence similarities with other PKA‐Cs, and it was clustered first with gastropod PKA‐Cs in the phylogenetic tree. The mRNA of HdPKA‐C was constitutively expressed in examined tissues, with the highest level detected in hepatopancreas. The phosphorylated form of HdPKA‐C (p‐HdPKA‐C) was localized at the acrosome, connecting piece and flagellum of spermatozoa with variable intensity. Its phosphorylated substrates were also detected in these regions with much lower intensity at the connecting piece. The inhibition of HdPKA‐C activity with H‐89 led to a significant reduction in the percentage of motile sperm and sperm velocities. p‐HdPKA‐C was detected by Western blot in strip‐spawned sperm, naturally spawned sperm and H‐89‐treated sperm with almost the same intensity. The intensity of p‐HdPKA‐C substrates in naturally spawned sperm was higher than that in strip‐spawned sperm, and it was roughly the same as that in H‐89‐treated sperm except for two bands at 50 and 60 kDa. These results collectively indicated that HdPKA‐C played an important role in the regulation of abalone sperm motility by altering its substrates phosphorylation.     

小麦茎基腐病防治药剂及抗病品种的筛选

为获得防治小麦茎基腐病的有效药剂和抗病品种,测定12种杀菌剂对小麦茎基腐主要病原菌假禾谷镰孢菌Fusarium pseudograminearum的室内毒力、对小麦生长的影响及对小麦茎基腐病的室内防治效果,并鉴定144份小麦品种（系）对茎基腐病的抗性。结果表明,12种杀菌剂对假禾谷镰孢菌均有一定的抑制效果,其中15%氰烯菌酯·5%己唑醇的抑制率最高,EC₅₀为0.002 mg/L,其次是6.6%嘧菌酯·1.1%咯菌腈·3.3%精甲霜灵、25 g/L咯菌腈和430 g/L戊唑醇,EC₅₀分别为0.016、0.069和0.099 mg/L。12种杀菌剂拌种处理对小麦出苗、株高、根长和鲜重均有不同程度的影响,尤其对出苗率影响最大,其中15%氰烯菌酯·5%己唑醇处理的出苗率最低,为30.41%。15%氰烯菌酯·5%己唑醇拌种处理的防治效果最好,为70.43%;其次是430 g/L戊唑醇和25 g/L咯菌腈·37.5 g/L精甲霜灵,防治效果分别为56.34%和53.34%。在供试144份小麦品种（系）中,仅3份对小麦茎基腐病表现为中感,其余141份均表现为高感,无免疫和抗病品种。综上,目前防治小麦茎基腐病时建议选用15%氰烯菌酯·5%己唑醇等杀菌剂进行拌种处理,但应严格控制药剂用量,以防影响小麦出苗。     

“百寿石头缘份”的景石艺术

怎样才能充分展示景石的艺术魅力,如何通过园林布局来使之达到完美统一,增强景石艺术的感染力,"百寿石缘"的建设在这方面做了初步探索。