强光照和黑暗条件下刺参体壁的基因表达差异     

张立斌  冯其明  孙丽娜  房燕  徐冬雪  张涛  杨红生 《海洋学报(英文版)》2018,37(5):54-66

参对光照变化非常敏感，研究刺参对光照的分子响应非常重要。本研究应用RNA测序获取了刺参暴露于强光（“强光”）、正常光照（“对照”）和完全黑暗（“黑暗”）环境下体壁的基因表达谱情况，通过“对照”与“黑暗”，“对照”与“强光”和“黑暗”与“强光”的比较，在|log₂ ratio|≥1和FDR≤0.001的标准下分别发现了1161、113和1705个差异表达基因（DEGs）。基因本体分析表明，“cellular process”和“binding”在“生物过程”和“分子功能”类别中的DEGs富集最多，而“cell”和“cell part”在“细胞组分”类别中的DEGs富集最多。将DEGs与Kyoto Encyclopedia基因和基因组数据库上的于214、41和229条通路进行比对，发现了51、2和57条通路分别显著富集。本研究发现的光特异性DEGs可作为深入研究刺参对光照变化的生化适应机制的重要目标基因。  相似文献   

Study of the flood control scheduling scheme for the Three Gorges Reservoir in a catastrophic flood          下载免费PDF全文

Shanghong Zhang  Zhu Jing  Wenda Li  Yujun Yi  Yong Zhao 《水文研究》2018,32(11):1625-1634

The Three Gorges Project is the world's largest water conservancy project. According to the design standards for the 1,000‐year flood, flood diversion areas in the Jingjiang reach of the Yangtze River must be utilized to ensure the safety of the Jingjiang area and the city of Wuhan. However, once these areas are used, the economic and life loss in these areas may be very great. Therefore, it is vital to reduce this loss by developing a scheme that reduces the use of the flood diversion areas through flood regulation by the Three Gorges Reservoir (TGR), under the premise of ensuring the safety of the Three Gorges Dam. For a 1,000‐year flood on the basis of a highly destructive flood in 1954, this paper evaluates scheduling schemes in which flood diversion areas are or are not used. The schemes are simulated based on 2.5‐m resolution reservoir topography and an optimized model of dynamic capacity flood regulation. The simulation results show the following. (a) In accord with the normal flood‐control regulation discharge, the maximum water level above the dam should be not more than 175 m, which ensures the safety of the dam and reservoir area. However, it is necessary to utilize the flood diversion areas within the Jingjiang area, and flood discharge can reach 2.81 billion m³. (b) In the case of relying on the TGR to impound floodwaters independently rather than using the flood diversion areas, the maximum water level above the dam reaches 177.35 m, which is less than the flood check level of 180.4 m to ensure the safety of the Three Gorges Dam. The average increase of the TGR water level in the Chongqing area is not more than 0.11 m, which indicates no significant effect on the upstream reservoir area. Comparing the various scheduling schemes, when the flood diversion areas are not used, it is believed that the TGR can execute safe flood control for a 1,000‐year flood, thereby greatly reducing flood damage.  相似文献   

不同类型的高位虾池排污对秋茄幼苗生长的影响     

田园  陈光程  唐飞龙  郑春芳  叶勇 《海洋学报(英文版)》2018,37(6):112-120

中国多数红树林陆地边缘存在着大量的养虾池塘。这些养虾池塘可通过：（1）换塘外排废水，（2）清塘直排污泥影响周围的红树林。本研究共包含两个实验，来探讨这两种类型的排污对秋茄幼苗生长的影响。实验一模拟虾池常规换塘情况，研究换塘废水对秋茄幼苗生长的影响。实验二设置四种虾池清塘污泥沉积厚度（0 cm，2 cm，4 cm，8 cm），研究虾池清塘污泥的累积效应对秋茄幼苗生长的影响。结果如下：在5，15和25三种盐度下，虾池换塘废水未对秋茄生长指标造成显著影响；而清塘污泥对秋茄生长的影响与其沉积厚度有关，大多数生长参数在污泥沉积厚度为4 cm时呈现最大值。秋茄幼苗在适量的沉积厚度下加速了生长，且本实验秋茄幼苗对虾池清塘污泥的耐受性为沉积厚度8 cm。  相似文献   

贵州夜郎湖表层水体地球化学昼夜变化及其影响因素     

王家录  任娟  王勇  李维杰  娄昭  陈佳 《热带地理》2020,40(2):335-345

为探究岩溶水库水文地球化学行为过程,对贵州普定夜郎湖表层水体进行了为期3 d的高分辨率昼夜监测。结果表明：1）多变的天气和水文条件叠加导致水体离子指标昼夜变化不显著,规律性较差。而水温、DO、pH值、SpC、SIc、pCO₂等常规理化指标受水温变化和生物作用表现出明显的昼夜波动。2）利用亨利常数和主成分分析,得到温度变化、生物作用、人类活动、水库的蓄水与放水对夜郎湖水库水文地球化学特征变化的贡献率分别为21.66%、17.28%、14.08%和10.22%,说明作用于水库水文地球化学行为的因子具有多元性。3）δ ¹⁸O表现出与DO一致的波动趋势,即白天上升,晚上下降,反映在短时间尺度上,氢氧稳定同位素变化受控于生物过程（主要是呼吸作用过程）;而对比水库水体和大气降水的d-excess（d值）发现,水库水体的d值（8.21‰）显著偏低于当地大气降水的d值（9.64‰）,说明在长时间尺度上,主要受蒸发效应引起的不平衡分馏影响。  相似文献   

Spatial variation of the relationship between transport accessibility and the level of economic development in Qinghai-Tibet Plateau,China     

YANG Xue-ting  QIU Xiao-ping  FANG Yi-ping  XU Yun  ZHU Fu-biao 《山地科学学报》2019,(8)

As an important component of China' transportation systems, for a long time, the insufficient performance of transport in QinghaiTibet Plateau(QTP) was a bottleneck restricting the economic growth and social development in this area. Nevertheless, the implementation of the western development strategy has accelerated the preliminary construction of comprehensive transport network since 2000. Due to the large area and significant geographical heterogeneity, there is a growing need to understand the relationship between transportation and economic development based on the perspective of spatial difference. By using GIS-based raster analysis and Geographically Weighted Regression(GWR) model, we investigated the spatial-temporal distribution of highway, railway and airport accessibility, respectively, and estimated the correlation and heterogeneity between transport accessibility and the level of economic development. Results revealed that:(1) Transport accessibility in the QTP improved by 53.38% in the past 15 years, which is specifically embodied in the improvement of both highway and railway.(2) Accessibility presented prominent differentiation in the space, increasing from west to east and reducing with the rise of elevation, specifically, the best accessibility area of the highway is below 4000 m above sea level, while the area with an altitude of over 4000 m has the lowest aviation time cost.(3) In general, the long weighted average time cost to critical transport facilities posed significantly negative effect on county economic growth in QTP, more positively, the adverse effect gradually weakened over time.(4) Obvious heterogeneity exists at the influence of different transport accessibility factors on the level of economic development, reflecting both in the horizontal space and altitudinal belt. Therefore, region-specific policies should be addressed for the sustainable development of transport facilities as well as economy in the west mountain areas.  相似文献   

天气雷达数据处理系统人控应用软件     

佘勇  王贤勤  姚振东  王树才 《成都信息工程学院学报》1990,(4)

天气雷达用于抗灾和减灾很重要,本文提出一种人工降雨和驱冰雹软件,给出了程序流图,对编程的关键进行了分析,最后结果表明它能提高人控作业效率。  相似文献   

NaCl胁迫下杂交稻农艺性状配合力及遗传力分析     

方良俊 《广东海洋大学学报》2006,26(3):91-94

采用4×4不完全双列杂交设计,在NaCl胁迫下对杂交水稻主要农艺性状进行了配合力和遗传力分析.结果表明,在调查的10个性状中有4个性状受NaCl胁迫影响差异较大,母本的千粒重及父本的粒厚一般配力差异显著,杂交组合的株高、粒厚、结实率及千粒重特殊配合力差异极显著,其中杂交组合N28S×中花14具有较高的配合力,受NaCl胁迫影响较低。株高及千粒重的广义遗传力和狭义遗传力均较高,可作为杂交水稻耐盐性的选育依据。  相似文献   

基于ARP协议的网络主机地址的识别技术研究   总被引：3，自引：0，他引：3  

杨漫  周安民  方勇 《成都信息工程学院学报》2006,21(2):186-189

从移动IPv6工作原理入手，IP地址管理器是针对越来越严重的IP地址盗用现象而设计的一套有效的监控和管理IP地址的方案。分析与研究IP地址管理器中的信息收集模块后，以Winpcap为开发工具，利用ARP，附等协议完成对网络中活动主机的扫描以及信息（主机名、MAC、操作系统）的收集和识别。模块实现了对网络的自动实时监控，有效地提高了管理效率。  相似文献   

CPLD技术及其在现代时统中的应用     

杨蕾  胡永辉 《时间频率学报》2003,26(1):40-47

对CPLD(复杂可编程逻辑器件)技术的基本特征和发展趋势作了简要介绍,揭示了该技术在现代数字系统中的重要地位及作用.利用CPLD对时统设备IRIG-B码产生器进行集成,其实验结果表明,集成了的B码产生器不但简单、可靠,而且便于调试,克服了以往硬件电路复杂的缺点.  相似文献   

CCD联合平差方法及其初步实例检验     

YU Yong LI Jinling TANG Zhenghong WANG Guangli ZHAO Ming 《中国科学院上海天文台年刊》2003,(1)

在常规照相天体测量工作中 ,对暗天体的定位是采用逐级定标星过渡的方法实现的。由于星表系统差和局部差的存在 ,最终定位结果可能包含难以把握的误差积累。在CCD小视场观测情况下时常难以找到足够数量的定标星。鉴于此 ,推导了CCD观测联合平差方法的严格矢量表达式 ,以期通过共同星的过渡 ,实现大天区统一平差。原理上此方法可实现相对于河外天体的定位 ,以削弱星表系统差和局部差对定位结果的影响。讨论了CCD联合平差方法实现中的问题 ,包括底片常数模型选择、切点位置改正、共同星的较差改正和法方程解算方法等 ,并分析了具体的处理措施。用实例初步检验了CCD联合平差方法的效果 ,表明通过对多张CCD观测的联合平差 ,可以削弱单张CCD观测参考星数目过少、单张CCD观测参考星分布不均、个别参考星存在位置偏差和局部区域参考星存在系统性位置偏差等不利因素对归算结果的影响 ,进而达到扩大视场和提高归算精度的目的  相似文献