稀土对3’,5’-环腺嘌呤单核苷酸与3’,5’-环鸟嘌呤单核苷酸的快速断裂作用

在温和条件下能快速切断核酸的人工酶有许多重要的潜在应用价值,如作为模拟的限制性内切酶并发展到新的抗癌药物,因此,长期以来人们致力于研究具有高效率及高选择性的人工酶.关于稀土对核酸断裂作用的研究尚不多,而稀土对环核苷酸的催化水解作用只有Sumaoka等曾报道Ce~(3+)对3’,5’-环腺嘌呤单核苷酸(cAMP)有快速的水解作用,稀土对不同环核苷酸的催化水解作用尚未见报道.3’,5’-环腺嘌呤单核苷酸与3’,5’-环鸟嘌呤单核苷酸(cGMP)具有调节细胞应答及细胞间信息传递的作用,且细胞内不同环核苷酸的变化与某些心血管疾病的发病机理有关.本文用高压液相色谱(HPLC)和核磁共振(NMR)研究了稀土对cAMP与cGMP的断裂作用,并深入探索了其机理,这对于寻找高效率及高选择性的核酸催化体系,阐明稀土在生物体内的作用具有重要的意义.

双功能有机物修饰电极的修饰层结构对催化细胞色素C的电极反应的影响

用光谱电化学法研究了双功能有机物健那绿的电化学性质。在铂电极上,健那绿发生四步单电子传递过程。在健那绿修饰电极上细胞色素C的直接、非均相电子传递反应是准可逆氧化还原反应,电极反应速率常数K_s=4.17×10~(-4)cm/s。电极表面的修饰方法不同对细胞色素C的电极反应有很大影响。

Isolation and characterization of microsatellite loci from mangrove red snapper Lutjanus argentimaculatus

Lutjanus argentimaculatus, also called mangrove red snapper, is a commercially important fish in East Asia. A proper understanding of population structure is primarily linked with the management of genetic resources in exploiting marine fisheries. Herein, seven microsatellite loci, which showed high polymorphism (observed heterozygosity per locus ranging from 0.3571 to 0.7857 and expected heterozygosity per locus ranging from 0.6236 to 0.8821), were isolated and characterized from L. argentimaculatus. Cross-species amplifications also indicate that primers designed for these loci may be useful for further studies about other closely phylogenetic species of the family Lutjanidae.

Population genetics of Crassostrea ariakensis in Asia inferred from microsatellite markers

Crassostrea ariakensis is an important aquacultured oyster species in Asia, its native region. During the past decade, consideration was given to introducing C. ariakensis into Chesapeake Bay, in the United States, to help revive the declining native oyster industry and bolster the local ecosystem. Little is known about the ecology and biology of this species in Asia due to confusion with nomenclature and difficulty in accurately identifying the species of wild populations in their natural environment. Even less research has been done on the population genetics of native populations of C. ariakensis in Asia. We examined the magnitude and pattern of genetic differentiation among 10 wild populations of C. ariakensis from its confirmed distribution range using eight polymorphic microsatellite markers. Results showed a small but significant global theta (ST) (0.018), indicating genetic heterogeneity among populations. Eight genetically distinct populations were further distinguished based on population pairwise theta (ST) comparisons, including one in Japan, four in China, and three populations along the coast of South Korea. A significant positive association was detected between genetic and geographic distances among populations, suggesting a genetic pattern of isolation by distance. This research represents a novel observation on wild genetic population structuring in a coastal bivalve species along the coast of the northwest Pacific.

高寒草甸土壤有机碳储量及其垂直分布特征

青藏高原是全球变化的敏感区．高寒草甸草原是青藏高原上最主要的放牧利用草地资源之一．选择青藏高原东北隅海北站内具有代表性的高寒草甸土壤进行高分辨率采样．测定土壤根系和有机碳含量．研究得出．青藏高原高寒草甸土壤贮存有巨大的根系生物量（23544．60kgha^-1～27947kgha^-1）和土壤有机碳（21．52GtC）：自然土壤表层（0-10cm）储存了整个剖面土壤有机碳总量的30％左右。比较发现．高寒草甸土壤的有机碳平均贮存量（23．17×10^4kgCha^-1）（0-60cm）较相应深度的热带森林土壤、灌丛土壤和草地土壤的有机碳贮存量高约1～5倍多。在全球碳预算研究中．青藏高原高寒草甸土壤有机碳库不可忽视。随着全球变暖．表层土壤有机碳分解释放的CO2将增加。为了减少高寒草甸生态系统的碳排放。应加强高寒草甸土壤地表覆被的保护．合理种植深根系植物。这对减缓全球大气CO2浓度升高的速率以及可持续开发高寒草甸的生态服务功能都具有重要意义。

机器人语言研究

本文从信息控制的角度出发将机器人语言定义为能处理某些特定的“外部设备”的计算机程序设计语言。并将机器人语言成份分为两大部分,即机器人核心语言和机器人专用语言。然后分别综述了机器人专用语言和机器人核心语言的进展情况。

阿尔泰南缘侧向增生过程中的VMS矿床：地质、地球化学特征与成矿机制

The Chinese Altai is one of the most important volcanogenic massive sulfide (VMS) deposit districts in China. All orebodies were lenticular or bedded and stratabounded by a suite of early Devonian volcanic-sedimentary rocks. Hydrothermal feeder zones developed under some of the orebodies. All the ores are massive or laminated, and show typical characteristics of VMS deposit. Based on the mineralizing time and the metal assembles, we divide 3 metallogenic stages: 1, Fe orefroming stage associated with basaltic and sedimentary rocks during very early Devonian; 2, Cu-Pb-Zn oreforming stage associated with rhyolitic and sedimentary rocks during early Devonian; 3， Cu-Zn oreforming stage in the dacitic and basaltic rocks during mid. Devonian. The hosting rocks for all orebodies are different, but they show very similar geochemical and isotopic characteristics. All the felsic rocks show enriched lighted rare earth elements (REE) patterns (La/Yb>5), and with an obvious Eu negative anomalies (Eu/Eu*<0.6). In the meanwhile, all the mafic rocks show flat REE pattern and no Eu anomalies. The Ashele basalt show an apparent Ce negative anomalies (Ce/Ce* <0.76), All the volcanic roks in Chinese Altai show the decoupled property between the high field strength elements (HFSE) and large ion lithophile elements (LILE). The negative Nb, Ta characteristics with respect to adjacent elements indicate that subduction-modified source. The Nd(t) of the hosting rocks for all orebodies changed in a small range (-1.5~5), and the (87Sr/86Sr)i change in a big range. The initial Sr value of the hosting rocks in Mengku and Tiemuerte are obviously affected by the seawater (0.705~0.710), and initial Sr values of hosting rocks Ashele change in a small range (0.704~0.706). All Sr-Nd isotopes of ores have the same range with the hosting rocks, indicating that both the ores and volcanic rocks have the same island arc source. The mean sulfur isotopes of sulfides from Ashele and Mengku are 6.2‰ and 3.4‰, respectively, indicating a deep magmatic source. However, the sulfur isotopes of sulfides from Keketale, Tiemuerte and Keyinbulake changed in -15.8‰~9.9‰, -23.5‰~1.87‰, -8.3‰~1.6‰, respectively. And the big sulfur isotope range indicated that the sulfur of the ores was a combination biogenic and magmatic source. All volcanic rocks from the VMS deposits in the southern Chinese Altai show a typical subduction related environments. Based on the regional and locally geological evidence, here we propose that the southern Chinese Altai is an island arc system, and all VMS deposits formed during the lateral accretion process. No VMS deposit formed during the formation of the island arc during Silurian; Fe VMS deposit formed during the beginning of the opening of the backarc basin in very early Devonian; Cu-Pb-Zn VMS deposits formed during the mature stage of the backarc basin in early Devonian; at last the Cu-Zn VMS deposit formed during the rifted stage of the island arc itself.

铜、锌同位素的化学前处理方法

过渡族金属同位素研究是近几年才发展起来的研究领域,在环境、生物、成矿和天体化学方面有着巨大的发展潜力.但过渡族金属的分离和同位素的测定方法并不十分成熟.本文就过渡金属同位素的测定方法做了简要概述并通过条件试验得出一些简单结论.

贵阳市表层土壤中镍的基线及污染研究

以贵州省贵阳市8 046 km2 为研究区域, 将土壤中镍的空间分布规律与环境地球化学机理研究相结合, 建立镍的区域土壤环境地球化学基线, 并进行污染分析. 通过对332 个样品的分析, 得到以下结论: 贵阳市表层土壤中镍的基线值为1710 mg/ kg , 大于5710 mg/ kg 的样品可能遭受人为污染. 地质累积指数分析结果显示贵阳市1912 %的表层土壤未受镍的污染, 6317 %的表层土壤在无污染到中度污染之间, 1618 % 的中度污染, 只有013 %的表层土壤介于中度污染到强污染之间. 污染程度指数分析则显示贵阳市64 %的表层土壤未受到镍的污染, 镍的污染程度最大为1156 , 总污染程度小于0 , 即总体未受到污染.