Intragenic and intergenic sequences regulating the expression of the 5''-to-5'' linked adult αand β-globin genes from large yellow croaker Pseudosciaena crocea     

CHU Wuying  YU Lian  QIAN Ronghu  MENG Tao  ZHOU Ruixue  FU Guihong  CHEN Ji  ZHANG Jianshe 《海洋学报(英文版)》2008,27(5):126-133

One adult α-globin gene and one β-globin gene have been cloned from the large yellow croaker Pseudosciaena crocea. Linkage analysis indicated that the α- and β-globin genes were oriented head-to-head relative to each other. To identify the regulatory elements present in the intergenic and intragenic regions of the globin complex, the intergenic region alone or together with the β-globin gene first intron was cloned into the luciferase-reporter vector pGL3-Basic respectively, and the chimeric constructs were tran- siently transfected into Vero cells and primary fish erythrocytes. The intergenic region cannot support the high-level expression of luciferase. However, the promoter activity of the intergenic region was strongly stimulated by the positive regulatory elements （PRE） located in the β-globin gene intron 1. Thus, it is proposed that the intergenic promoters and intragenic PRE were necessary for the effective expression of the linked α- and β-globin genes.  相似文献   

Detecting the storage and change on topsoil organic carbon in grasslands of Inner Mongolia from 1980s to 2010s   总被引：2，自引：2，他引：0  

Erfu Dai  Ruixue Zhai  Quansheng Ge  Xiuqin Wu 《地理学报(英文版)》2014,24(6):1035-1046

Soil carbon sequestration and potential has been a focal issue in global carbon research. Under the background of global change, the estimation of the size as well as its change of soil organic carbon（SOC） storage is of great importance. Based on soil data from the second national soil survey and field survey during 2011–2012, by using the regression method between sampling soil data and remote sensing data, this paper aimed to investigate spatial distribution and changes of topsoil（0–20 cm） organic carbon storage in grasslands of Inner Mongolia between the 1980 s and 2010 s. The results showed that：（1） the SOC storage in grasslands of Inner Mongolia between the 1980 s and 2010 s was estimated to be 2.05 and 2.17 Pg C, with an average density of 3.48 and 3.69 kg C·m–2, respectively. The SOC storage was mainly distributed in the typical steppe and meadow steppe, which accounted for over 98% of the total SOC storage. The spatial distribution showed a decreased trend from the meadow steppe, typical steppe to the desert steppe, corresponding to the temperature and precipitation gradient.（2） SOC changes during 1982–2012 were estimated to be 0.12 Pg C, at 7.00 g C·m–2·yr–1, which didn＇t show a significant change, indicating that SOC storage in grasslands of Inner Mongolia remained relatively stable over this period. However, topsoil organic carbon showed different trends of carbon source/sink during the past three decades. Meadow steppe and typical steppe had sequestered 0.15 and 0.03 Pg C, respectively, served as a carbon sink; while desert steppe lost 0.06 Pg C, served as a carbon source. It appears that SOC storage in grassland ecosystem may respond differently to climate change, related to vegetation type, regional climate type and grazing intensity. These results might give advice to decision makers on adopting suitable countermeasures for sustainable grassland utilization and protection.  相似文献   

黑河中游不同土地覆被类型土壤呼吸及对水热因子的响应   总被引：1，自引：0，他引：1  

牛瑞雪  刘继亮  胡彦萍  付英 《中国沙漠》2017,37(5):961-969

以黑河中游6种典型土地覆被类型（百年灌溉农田、新垦灌溉农田、人工杨树林、人工樟子松林、人工梭梭灌木林和天然荒漠草地）为研究对象,对土壤呼吸及其对土壤含水量和土壤温度的响应进行测定。结果表明：灌溉农田的土壤呼吸速率显著大于人工樟子松林地和杨树林地,人工林地显著大于荒漠草地和梭梭灌木林地。6种土地覆被类型土壤呼吸速率与土壤温度显著正相关性,Q₁₀值1.14~1.31,表明该地区土壤呼吸速率对土壤温度的敏感性低于世界平均水平;土壤呼吸速率与土壤含水量呈显著的指数关系。这表明6种土地覆被类型的土壤呼吸特征存在显著差异,且不同土地覆被类型的土壤呼吸特征与水热因子关系密切,以人类活动为主导的土地覆被变化深刻影响着荒漠绿洲生态系统水土气生的相互作用。  相似文献   

Risk analysis of tripping accidents of power grid caused by typical natural hazards based on FTA-BN model     

Bian  Haifeng  Zhang  Jun  Li  Ruixue  Zhao  Huanhuan  Wang  Xuexue  Bai  Yiping 《Natural Hazards》2021,106(3):1771-1795

As the scale of the power grid becomes larger, the requirements for transmission reliability are getting higher. Due to the large geographical span and the harsh environment of the power transmission line, it has become the most severely affected equipment of the power grid by natural factors. However, the quantitative assessment of transmission line tripping accidents caused by multiple natural hazards has rarely been investigated. In this study, a risk analysis method to probabilistically analyze the tripping accidents of power transmission lines caused by wildfire, lightning, strong wind and ice storm was proposed. The analysis process consists of comprehensively identifying the risk of tripping accidents based on fault tree analysis and dynamically performing the predictive analysis of tripping accident evolution process in transmission line from causes to consequences based on Bayesian network. Critical risk evolution paths corresponding to four natural hazards are determined through a 72-node BN. The source risks of the four critical risk evolution paths are artificial ignition source from the wildfire path, aging from the lightning path, thoughtless of surrounding environment from the strong wind path and wind effect from the ice storm path. The countermeasures of tripping accidents are derived through the source risks and synergy between risks in three scenario analysis. This study is expected to examine the key challenges of risk management in power grid tripping accidents, which provides technical supports for accident preventing, handling and recovering of tripping accidents of the power transmission line according to “scenario–response”-based hazard response strategy.

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关于中国大西洋海洋战略布局的几点思考          下载免费PDF全文

刘大海  连晨超  刘芳明  王春娟  纪瑞雪  李晓璇 《海洋开发与管理》2016,33(5):3-7

随着综合国力的不断增长和海洋力量的不断提升,中国在大西洋的海外利益不断延伸,这对中国的海洋战略提出了新的要求。在《中华人民共和国深海海底区域资源勘探开发法》出台背景下,提前谋划中国的大西洋海洋战略十分必要。文章系统阐述了大西洋的全球战略地位,从政治与外交、军事与安全、经济与贸易、科技与环保等方面分析其对中国的战略意义,探讨大西洋海洋战略布局的目标框架。在此基础上,对中国大西洋战略布局进行现实考量,提出全面构建大西洋伙伴关系,提升大西洋资源调查、勘探和开发能力,中国海警加快融入国际海上搜寻救助体系等建议。  相似文献   

冰封期达里诺尔湖同位素与营养盐分布特征及关系的定量分析   总被引：1，自引：0，他引：1  

刘晓旭  李畅游  李文宝  赵胜男  甄志磊  刘志娇  于瑞雪 《湖泊科学》2015,27(6):1159-1167

以内蒙古高原的达里诺尔湖为研究对象,对其在冰封期湖水不同相态下总氮(TN)、总磷(TP)浓度以及氢、氧同位素比值的分布特征和定量关系进行初步研究.结果表明:1)在冰封期,达里诺尔湖水体中营养盐的平均浓度相对较高,已远超过国家Ⅴ类水质标准.水体中TN、TP浓度均大于其在对应冰体中的浓度,均值分别是对应冰体中的9.91、3.11倍,说明低温冷冻过程对达里诺尔湖水体中的氮、磷具有浓缩效应.而通过与非冰封期的对比发现,湖冰的排氮效应强于磷.2)冰封期由于结冰过程中同位素热力学分馏明显,加之贡格尔河的入流补给,使得达里诺尔湖冰体中的氢、氧同位素比值远高于水体中的比值,同时,随冰层的加深,同位素逐渐偏重.3)冰封期达里诺尔湖水体及冰体中,同位素比值与营养盐浓度均呈显著负相关,水体的相关性较冰体要好,在冰层中,随着冰层的加深相关性越明显.利用SPSS统计软件分析发现同位素比值与营养盐浓度的相关关系显著,水体中最大相关系数达到0.991,冰体中达到0.988;氢同位素(D)与TN、TP浓度的关系式分别为:TN=-0.2825δD-6.0083和TP=-0.0805δD-1.2395,这为研究湖泊营养盐的时空变化规律提供新的手段和理论.  相似文献   

大型溞(Daphnia magna)线粒体基因组的测定与序列分析     

程瑞雪  邓斌  王亚玲  耿雪侠  李俊  张旭  彭树英  邓道贵  张海军 《湖泊科学》2016,28(2):414-420

利用Long-PCR及普通PCR技术,结合引物步移法测序,经拼接、组装后获得中国淮河大型溞(Daphnia magna)线粒体基因组全序列,并对其基因组成、结构特点等进行初步分析.大型溞线粒体基因组全长为14948 bp,A、T、G、C各碱基含量分别为32.37%、34.73%、15.58%、17.31%,表现出明显的AT偏倚.13个蛋白质编码基因、22个t RNA基因、2个rRNA基因和1个D-loop区(控制区)的排列方式与典型的节肢动物线粒体基因组的排列方式略有不同.除COI基因以CTG、ATP8基因以GTG、ND3基因以ATC以及ND6基因以ATT为起始密码子以外,其余9个蛋白质编码基因均以ATG作为起始密码子;9个蛋白质编码基因具有典型的完全终止子TAG或TAA,COI、COII、ND4和ND5等基因采用不完全终止密码子T.基因组包含9个基因间隔区,共81 bp,长度1~62 bp;13个基因重叠区,共77 bp,重叠碱基数在1~27 bp之间,最大重叠在16 S rRNA和tRNA~(Val)基因之间.在预测的22个tRNA基因的二级结构中,发现只有tRNA~(Ser1)基因未能形成完整的二级结构,其他21个基因均可形成典型的三叶草结构.16 S rRNA和12 S rRNA基因长度分别为1373 bp和752 bp,D-loop区全长289 bp.本研究结果为探讨大型溞在溞属中的系统学地位及其与其他种间的系统发生关系等问题提供了数据资源.  相似文献