方捆打捆机打结装置的研究现状及发展趋势

打结装置作为方捆机的核心部件,其质量好坏直接影响整机工作效率与稳定性。通过对方捆机打结装置主要类型D型打结器、C型打结器和双结打结器进行介绍,并重点对D型打结器驱动齿盘、绕扣机构、割绳脱扣机构的影响因素及其研究现状进行分析研究,提出打结装置应向高性能、智能化及新机型的发展趋势,为打结器国产化研究提供重要参考依据。

物候观测在美国白蛾监测预报中的应用

通过建立关联性较强的物候关系,不仅提高了监测的精准性,而且降低了监测成本,生产中不需要每年都进行烦琐的灯诱、性诱和人工观测等专业性较强的工作,可操作性强。

Effect of Wuziyanzong pill on levels of sex hormones, and expressions of nuclear- associated antigen Ki-67 and androgen receptor in testes of young rats

OBJECTIVE: To evaluate the effects of Wuziyanzong pill on the levels of serum follicle stimulating hormone(FSH), luteinizing hormone(LH), testosterone(T) and the expressions of nuclear-associated antigen Ki67(Ki67), androgen receptor(AR) in testes of young rats.METHODS: Sixteen 20-day-old Wistar male rats were randomly divided into control and treatment group(n = 8). Rats in treatment group were administered Wuziyanzong pill by gavage; rats in control group administered the same volume of saline. After 10 days of treatment, the rats were killed, and then serum and testes were taken. The levels of FSH, LH and T were measured by radioimmunoassay(RIA). The histology of seminiferous tubule was observed by hematoxylin-eosin(HE) staining. The expression of Ki67 was detected by immunohistochemical assay(IHC). The m RNA level of Ki67, ARand CK-18 was detected with quantitative real-time polymerase chain reaction(Q-RT-PCR), the protein level of AR and CK-18 were tested by Western blot.RESULTS: Compared with control group, T level in treatment group increased significantly(P < 0.05).HE staining showed that both leydig cells and germ cells increased in treatment group. Expressions of Ki67 and AR became higher after treatment. There were no changes in CK-18 expression.CONCLUSION: Wuziyanzong pill can up-regulate AR level to promote germ cell proliferation and differentiation in young male rats.

松材线虫感染松树致死机理及防治实践分析

作者从树木生理学的角度分析,松材线虫(Bursaphelenchus xylophilus)短时间内致死松树的原因是松树对松材线虫的入侵过于敏感,造成韧皮部和木质部大量细胞程序化死亡,严重破坏松树的输导系统,造成感病松树在短时间内死亡。当前的防治都是阻止传播。文章从直接杀死松材线虫和提高松树抗性方面提出了实践性的思考,为从根本上防治松材线虫病提供了新的思路。

五莲山野生杜鹃薄沙床播种育苗技术

该技术采用薄沙床播种育苗,很好的解决了微粒种子发芽对水分和土壤通透性的要求,解决了覆土厚度难以掌握的问题,满足了每粒种子发芽所需要的条件,使种子发芽率和苗木成活率提高,单位面积产苗量大。种子发芽后,根系很快就能接触到沙层下的育苗基质,及时满足了苗木生长对养分的需求,不需要进行芽苗移栽,减少了对幼苗的伤害,延长了苗木生长的时间,有利于提高苗木的质量和产量,创造最高的效益。