MALE PEACH APHID ATTRACTION IN THE FIELD BY SEX PHEROMONES1)

Abstract Field trials by sex pheromone of aphid to trap peach aphids Myzus persicae have been carried out in 1995 and in 1996. Suitable time and the effect of ratio of two components nepetalactone and nepetalactol to apply the lure have been observed.     

LGR5 regulates osteogenic differentiation of human thoracic ligamentum flavum cells by Wnt signalling pathway

Thoracic ossification of the ligamentum flavum (TOLF) is ectopic ossification of the spinal ligaments. Histologically, the development of TOLF can be described as the process of endochondral ossification. However, the underlying aetiology has not been completely clarified. In this investigation, the gene expression profile associated with leucine‐rich repeat‐containing G‐protein‐coupled receptors (LGR) and Wnt signalling pathway in the thoracic ligamentum flavum cells (TLFCs) of different ossification stages was analysed via RNA sequencing. We further confirmed the significant differences in the related gene expression profile by Gene Ontology (GO) enrichment analysis. LGR5 was first identified in primary human TLFCs during osteogenic differentiation. To evaluate the effect of LGR5 on osteogenic differentiation, LGR5 has been knocked down and overexpressed in human TLFCs. We observed that the knockdown of LGR5 inhibited the activity of Wnt signalling and attenuated the potential osteogenic differentiation of TLFCs, while overexpression of LGR5 activated the Wnt signalling pathway and increased osteogenic differentiation. Our results provide important evidence for the potent positive mediatory effects of LGR5 on osteogenesis by enhancing the Wnt signalling pathway in TOLF.     

In Situ TEM Study of Volume Expansion in Porous Carbon Nanofiber/Sulfur Cathodes with Exceptional High‐Rate Performance

Although lithium sulfur batteries (LSBs) have attracted much interest owing to their high energy densities, synthesis of high‐rate cathodes and understanding their volume expansion behavior still remain challenging. Herein, electrospinning is used to prepare porous carbon nanofiber (PCNF) hosts, where both the pore volume and surface area are tailored by optimizing the sacrificial agent content and the activation temperature. Benefiting from the ameliorating functional features of high electrical conductivity, large pore volume, and Li ion permselective micropores, the PCNF/A550/S electrode activated at 550 °C exhibits a high sulfur loading of 71 wt%, a high capacity of 945 mA h g^?1 at 1 C, and excellent high‐rate capability. The in situ transmission electron microscope examination reveals that the lithiation product, Li₂S, is contained within the electrode with only ≈35% volume expansion and the carbon host remains intact without fracture. In contrast, the PCNF/A750/S electrode with damaged carbon spheres exhibits sulfur sublimation, a larger volume expansion of over 61%, and overflowing of Li₂S, a testament to its poor cyclic stability. These findings provide, for the first time, a new insight into the correlation between volume expansion and electrochemical performance of the electrode, offering a potential design strategy to synthesize high‐rate and stable LSB cathodes.     

外源ABA对大蒜试管苗玻璃化发生和抗氧化系统的影响

以大蒜品种‘二水早’试管苗为材料,从活性氧代谢的角度研究了外源ABA、H_2O_2和H_2O_2+ABA处理下的试管苗玻璃化率、活性氧积累与组织定位和抗氧化系统的响应特征,探讨ABA缓解试管苗玻璃化过程的机理。结果表明:(1)外源H_2O_2处理可诱导大蒜试管苗玻璃化发生,外源ABA处理下玻璃化率最低,可以缓解H_2O_2诱导的玻璃化的发生。(2)试管苗O_2~产生速率和H_2O_2含量在H_2O_2处理下最高,在ABA处理下最低;在添加H_2O_2的培养基中同时添加ABA能显著减少因外源H_2O_2处理引起的O_2~产生和H_2O_2积累。(3)试管苗CAT、POD和APX活性在外源H_2O_2处理前期(0~8d)均上升并显著高于对照,但其CAT、APX活性在处理后期(8~16d)下降,其同期POD活性也增加缓慢;各抗氧化酶的活性在外源ABA与H_2O_2+ABA处理前期(0~8d)均呈直线上升趋势,而它们在H_2O_2+ABA处理后期(8~16d)均显著高于H_2O_2处理。(4)各处理试管苗抗坏血酸和谷胱甘肽含量随处理时间先升高后降低,并以外源ABA处理下最高,外源H_2O_2处理下最低。(5)试管苗O_2~和H_2O_2产生部位主要在基部和叶尖,且外源ABA处理下组织中ROS的积累最少。(6)在ABA+H_2O_2处理下,大蒜试管苗内丙二醛含量和膜相对透性显著低于对照和H_2O_2处理。研究发现,外源ABA处理可有效降低大蒜试管苗的内源O_2~产生速率和H_2O_2含量,提高抗氧化酶活性和抗氧化物质含量,抑制活性氧在试管苗内的产生和运输,显著降低试管苗玻璃化率;外源ABA可通过增强大蒜试管苗抗氧化能力来抑制玻璃化发生。