A matricellular protein and EGF-like repeat signalling in the social amoebozoan Dictyostelium discoideum

Matricellular proteins interact with the extracellular matrix (ECM) and modulate cellular processes by binding to cell surface receptors and initiating intracellular signal transduction. Their association with the ECM and the ability of some members of this protein family to regulate cell motility have opened up new avenues of research to investigate their functions in normal and diseased cells. In this review, we summarize the research on CyrA, an ECM calmodulin-binding protein in Dictyostelium. CyrA is proteolytically cleaved into smaller EGF-like (EGFL) repeat containing cleavage products during development. The first EGFL repeat of CyrA binds to the cell surface and activates a novel signalling pathway that modulates cell motility in this model organism. The similarity of CyrA to the most well-characterized matricellular proteins in mammals allows it to be designated as the first matricellular protein identified in Dictyostelium.     

内蒙古四子王旗带状柠条林根系体积空间分布特征

在内蒙古四子王旗采用挖掘法对不同带间距柠条林地灌草根系体积的空间分布特征进行研究,结果表明:带间灌草根系体积水平分布为全部根系与直径≥0.5 mm根系分布特征相似;直径≤0.2 mm根系对全部根系分布特征的影响在近柠条带1.5 m之内,对16 m带间距林地的影响在2.0 m之后,且呈波状变化;根系体积垂直分布总体上随着土层的加深而减少,随着带间距的加大表土层根系逐渐增加;5 m带间距时遵从y=aebx函数关系,10 m、16 m带间距时遵从y=aLn(x)+b函数关系.16 m带间距林地根系水平分布相对均匀,垂直分布在0～20 cm土层比例较大,是比较适合该地区的灌草复合林地.     

应用激光反射仪研究聚氧乙烯十二烷基醚溶液在硅片表面上的吸附解吸过程(英文)

将激光反射仪应用于溶液吸附上,考察了聚氧乙烯十二烷基醚--一种非离子表面活性剂溶液在硅片表面上的吸附解吸过程,结果表明其吸附过程极快,30s 达到稳定值,且解吸完全.其最大吸附量Г(mg·m-2)是2.45 mg·m-2.在临界表面相关浓度CSAC(0.045 5 mmol·L-1)以下的浓度范围内,吸附模型符合Langmuir模型.     

一种新型的电焊机节能装置

本文根据焊接变压器的基本原理,研究了一种交流弧焊机的节能装置。