广东蛇蚊春蜓属Ophiogom phus Selys一新种描述(蜻蜓目:春蜓科)

广东蛇蚊春蜓,新种Ophiogomphus(Ophinurus)guangdongens Chao,sp.nov 本新种放在蛇纹春蜓属Ophiogomphus Selys里,主要是根据臀圈3室这个特征。它的后钩片末端有短指状突,下肛附器在侧面观有三角形背侧突,符合Ophinurus亚属特征。本新种头部和胸部色彩以及肛附器与中华蛇纹春蜓Ophiogomphus(Ophinurus)sinicus Chao十分相似,但本种身体较小,前钩片无后枝,后钩片末端突起很短,也不钩曲,这些特征都与sinicus不同,阳茎形状与sinicus差异更大,腹部第7、8两节背板没有一丛黑色长色,可与sinicus区别。 就下肛附器在侧面观有背侧突而言,本新种和中华蛇纹春蜓都与基齿奈春蜓Nychogomphus duaricus (Fraser)和黄尾奈春蜓Nychogomphus flavicaudus (Chao)相似,但是Nychogomphus臀圈1室,有时2室,易与Ophiogomphus区别。 台,正模,广东省封开县,黑石顶,1985.Ⅵ.5,梁铬球采,藏广州中山大学昆虫研究所。     

Contributions of DPOR at Low Light Intensi.ty to Chlorophyll Biosynthesis and Growth in the Synechocystis sp. PCC 6803

Introduction Chlorophylls (Chls) and bacteriochlorophylls (Bchls) are two of the most abundant classes of natural pigments, and their biosynthesis is a major metabolic activity in the ecosystem[1]. Protochlorophyllide (Pchlide) is an intermediate in the Chl and Bchl biosynthetic pathway of photosynthetic organisms and its reduction to chlorophyllide (Chlide) is a key regulatory step in the Chl biosynthesis pathway. In this reaction, the porphyrin D-ring of Pchlide is converted to chlorin b…     

两个新的海洋神经酰胺

从南海海绵Spongia sp.中分离得到两个新的神经酰胺,spongiamine A(1)和sprongiamine B(2),通过IR,1D NMR,2D NMR,MS,MSn等波谱方法,确定了它们的结构分别为N-(2＇-羟基-正-二十四碳酰基)-1,3,4-三羟基-正-十五烷-鞘胺醇(1)和N-(2＇-羟基-正-二十四碳酰基)-正-二十碳-4(E)烯-鞘胺醇(2).     

Structure and stereochemistry of brianolide,a new antiinflammatory diterpenoid from the Okinawan gorgonianBriareum sp.

Summary Brianolide (1), a new antiinflammatory diterpenoid of the briarein class, possessing a substituent at C-12 (R), has been isolated from the Okinawan gorgonianBriareum sp. Its structure has been established from spectral data in conjunction with a single crystal X-ray analysis.     

影响空心莲子草镰刀菌生长发育的几个重要因子分析

在原有试验发现空心莲子镰刀菌草生长产孢对光照、通气及淹水与否不敏感的基础上,该研究进一步测定营养培养基、温度和酸碱度因子对空心莲子草镰刀菌生长发育的影响.研究结果表明,这3个因子对此真菌菌落生长、分生孢子产生和萌发都有极显著的作用,所以认为它们是影响真菌生长发育的关键因子.真菌菌落生长和产孢的温度范围为15℃～30℃,在25℃时生长最快而产孢最多;分生孢子萌发的适温范围是20℃～35℃,在30℃时萌发率显著高于其它温度处理.对6种培养基的测定结果显示,真菌在马铃薯葡萄糖培养基(PDA)、胡萝卜培养基(CAA)、空心莲子草根茎煎汁培养基(ARS)和空心莲子草叶片煎汁培养基(ALA)上都能够正常生长、产孢和萌发,而在清水洋菜培养基(WA)上不能生长发育,但是马铃薯蔗糖琼脂(PSA)是该真菌的最佳培养基.菌落生长和产孢的适宜酸碱度范围是pH 4.5～pH 11.0,最适约为pH 7.0,在pH 4.0和pH 12.0时生长和产孢都明显减缓;分生孢子萌发适宜的酸碱度范围为pH 4.0～pH 9.0,在pH 10.0～pH 12.0范围内孢子不能萌发.由此可见,在25℃和pH 7.0条件下使用PSA,是空心莲子草镰刀菌的最佳培养条件.     

Cesium accumulation by bacterium Thermus sp. TibetanG7： hints for biomineralization of cesiumbearing geyserite in hot sprinss in Tibet, China

The bacterium Thermus sp. TibetanG7, isolated from hot springs in Tibet, China, was examined for the ability to accumulate cesium from solutions. Environmental conditions were simulated and the effects of pH, K^＋, Na^＋and K^＋-regimes were then studied to determine the possible role of the bacterium in the formation of cesium-bearing geyserite around these hot springs. In despite of the inhibition of K^＋ and Na^＋, the bacterium Thermus sp. TibetanG7 revealed noticeable accumulation of cesium from solutions, with maximum accumulations of 53.49 and 40.41 pmol Cesium/g cell dry weight in Na^＋ and K^＋ inhibition experiments, respectively. The accumulation of cesium by this microorganism is rapid, with 40% --50% accumulated within the first 5 min. K^＋-deficient cells showed a much higher capacity of cesium accumulation compared with K^＋-sufficient cells. It is evident that the bacteria within the genus thermus play a significant role in the cesium assembly. The formation of cesium-bearing geyserite is also considered.     

固定化小球藻对市政污水中N,P营养盐的深度处理Ⅱ.细胞负载和饥饿处理对氮磷去除率的影响

将从污水中分离的小球藻包埋于褐藻酸钙胶球中，对人工配制的市政污水进行深度处理．研究了菏细胞负载，饥饿处理等因素对污水中NK4^ —N和PO4^3 —P的去除效率的影响以及处理过程中藻类的生长变化．结果表明，当细胞负载低于700万细胞／胶球／mL时，反应器对氮磷的去除率随细胞负载的增加而增加，而单位细胞对氮磷的去除量却随负载的增加而减少；对藻细胞进行饥饿处理，并不影响其细胞增殖量，但可明显提高其对NK4^ —N和PO4^3 —P的去除效率，在3d内对NK4^ —N和PO4^3 —P的去除率分别比对照净提高了13％和29％．     

铁限制诱导对聚球藻转录组的影响

为探究Fe元素限制对聚球藻转录组的影响,该文以聚球藻Synechococcus sp.PCC 7002为研究对象,采用高通量测序技术对经过铁限制处理的聚球藻Synechococcus sp.PCC 7002进行转录组分析.以铁的3种摩尔浓度进行处理,其中每组数据重复3次实验,一共获得9组实验数据;对照组摩尔浓度为10....