江西茅排金矿床地质特征及找矿方向   总被引：1，自引：0，他引：1  

钱姣风  许静 《江西地质》1998,12(1):36-41

茅排金矿是我省近年发现、探明的又一小—中型岩金矿床。震旦纪—早古生代火山沉积建造提供主要成矿物质,多期次构造活动为成矿主要的控制因素,同期岩浆活动也促进了矿化富集。可注意沿北东—北北东向韧－脆性断裂带旁侧,多期次构造－岩浆发育地段寻找类似金矿。  相似文献   

湖南农业抗旱能力综合评价   总被引：2，自引：0，他引：2  

刘迎春  肖谦益 《云南地理环境研究》2007,19(4):39-42,57

利用灰色系统理论中的关联分析建立了湖南农业抗旱能力评价的指标体系，运用密切值法对湖南14个地州市的抗旱能力进行了综合排序。其结果表明湖南省各州市的农业抗旱能力差异较大，其中：衡阳（0．03）、常德（0．32）密切值小，抗旱能力强，株洲（3．14）、张家界（3．34）密切值大，抗旱能力弱。并根据湖南的实际为其抗旱减灾、提高抗旱能力提出了合理的建议与对策。  相似文献   

Evaluation of an empirical orthogonal function–based method to downscale soil moisture patterns based on topographical attributes     

Frederick A. Busch  Jeffrey D. Niemann  Michael Coleman 《水文研究》2012,26(18):2696-2709

Soil moisture influences many hydrologic applications including agriculture, land management and flood prediction. Most remote‐sensing methods that estimate soil moisture produce coarse resolution patterns, so methods are required to downscale such patterns to the resolutions required by these applications (e.g. 10‐ to 30‐m grid cells). At such resolutions, topography is known to affect soil moisture patterns. Although methods have been proposed to downscale soil moisture based on topography, they usually require the availability of past high‐resolution soil moisture patterns from the application region. The objective of this article is to determine whether a single topographic‐based downscaling method can be used at multiple locations without relying on detailed local observations. The evaluated downscaling method is developed on the basis of empirical orthogonal function (EOF) analysis of space–time soil moisture data at a reference catchment. The most important EOFs are then estimated from topographic attributes, and the associated expansion coefficients are estimated on the basis of the spatial‐average soil moisture. To test the portability of this EOF‐based method, it is developed separately using four data sets (Tarrawarra, Tarrawarra 2, Cache la Poudre and Satellite Station), and the relationships that are derived from these data sets to estimate the EOFs and expansion coefficients are compared. In addition, each of these downscaling methods is applied not only for the catchment where it was developed but also to the other three catchments. The results suggest that the EOF downscaling method performs well for the location where it is developed, but its performance degrades when applied to other catchments. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

Expression of putative zinc-finger protein lcn61 gene in lymphocystis disease virus China （LCDV-cn） genome   总被引：1，自引：0，他引：1  

闫秀英  孙修勤 《中国海洋湖沼学报》2009,27(2):337-341

An open reading frame (lcn61) of lymphocystis disease virus China (LCDV-cn), probably responsible for encoding putative zinc-finger proteins was amplified and inserted into pET24a (+) vector. Then it expressed in E. coli BL21 (DE3), and His-tag fusion protein of high yield was obtained. It was found that the fusion protein existed in E. coli mainly as inclusion bodies. The bioinformatics analysis indicates that LCN61 is C2H2 type zinc-finger protein containing four C2H2 zinc-finger motifs. This work provides a theory for functional research of lcn61 gene. Supported by High Technology Research and Development Program of China (863 Program, No. 2006AA100309)  相似文献   

溶藻弧菌asp基因在大肠杆菌中表达活性研究及条件优化   总被引：1，自引：0，他引：1  

蔡双虎  鲁义善  吴灶和  简纪常  汤菊芬  黄郁葱 《广东海洋大学学报》2008,28(3)

为进一步研究溶藻弧菌碱性丝氨酸蛋白酶(ASP)蛋白生物学活性和功能,将构建的pET23d-asp在大肠杆菌BL21(DE3)中表达,对表达产物进行纯化分析,并优化表达条件。结果表明:在咪唑洗脱缓冲液浓度为100 mmol/L时,表达的可溶性ASP被大量洗脱,纯化的ASP相对分子质量约为42 000,具有蛋白活性;在诱导温度28℃、异丙基-β-D硫代半乳糖苷(Isopropyl-β-D-thiogalactopyranoside,IPTG)浓度1 mmol/L及诱导时间16 h时,表达的活性ASP蛋白最多。  相似文献   

Statistical analysis and forecasts of long-term sandbank evolution at Great Yarmouth, UK   总被引：4，自引：1，他引：3  

Dominic E. Reeve  Jos M. Horrillo-Caraballo  Vanesa Magar 《Estuarine, Coastal and Shelf Science》2008,79(3):387-399

A data-driven model has been developed to analyse the long-term evolution of a sandbank system and to make ensemble predictions in a period of 8 years. The method uses a combination of empirical orthogonal function (EOF) analysis, (to define spatial and temporal patterns of variability), jack-knife resampling, (to generate an ensemble of EOFs), a causal auto-regression technique, (to extrapolate the temporal eigenfunctions), and straightforward statistical analysis of the resulting ensemble of predictions to determine a ‘forecast’ and associated uncertainty. The methodology has been applied to a very demanding site which includes a curved shoreline and a group of mobile nearshore sandbanks. The site is on the eastern coast of the UK and includes the Great Yarmouth sandbanks and neighbouring shoreline. A sequence of 33 high quality historical survey charts reaching back to 1848 have been used to analyse the patterns and to predict morphological evolution of the sandbank system. The forecasts demonstrate an improved skill relative to an assumption of persistence, but suffer in locations where there are propagating features in the morphology that are not well-described by EOFs.  相似文献   

雄性半滑舌鳎雄激素受体基因的克隆与表达分析     

温海深  张葭人  陈彩芳  金国雄  陈晓燕  史宝  何峰 《中国海洋大学学报(自然科学版)》2009,39(3)

利用RT-PCR方法从半滑舌鳎(Cynoglossus semilaevis)中克隆了雄激素受体(Androgen receptor,AR)基因cDNA的部分序列(434 bp),经BLAST比对与狼鲈(Dicentrarchus labrax)、花溪(Kryptolebias marmoratus)、三斑海猪鱼(Halichoeres trimaculatus)和三刺鱼(Gasterosteus aculeatus)的雄激素受体同源性分别为84%,82%,82%和81%.组织表达分析表明,AR基因在半滑舌鳎的性腺、肝、胃、脾、肾、头肾、肠、鳃、心、脑和肌肉这11种组织中均有表达,表达量有所差异.肾中表达量最丰富,鳃中最少.根据其他硬骨鱼类表达模式,推测半滑舌鳎可能只含有1种AR.  相似文献   

黄东海表观光学量与固有光学量经验模式研究     

汪小勇  李铜基  刘炜  杨安安  毕大勇  李尉尉 《海洋技术学报》2008,27(1):58-65

表观光学特性和固有光学特性是海洋光学研究领域的两大主要研究内容。文中通过2003年黄东海试验和2007年908专项海洋光学调查所获取的表观光学参数中的遥感反射率Rrs(λ)、水下遥感反射率rrs(λ)、海水透明度Zs、下行辐照度漫衰减系数Kd(490)、固有光学参数中的后向散射系数bb(λ)和水体吸收系数a(λ),建立了区域性、季节性的表观光学量和固有光学量之间的经验模式,并对模式进行了误差分析和改进。  相似文献   

黄斑篮子鱼去毒相关基因的克隆与肝脏组成型表达分析   总被引：1，自引：0，他引：1  

王琳  梁旭方  林群  李光照  胡永乐 《热带海洋学报》2009,28(6):79-87

从基因水平探讨海洋鱼类对海洋藻毒素的去毒分子机理。采用RT-PCR法成功克隆了黄斑篮子鱼Siganus oramin肝脏I时相代谢酶细胞色素P450 1A(CYP1A)、II时相代谢酶alpha型谷胱甘肽S-转移酶(GSTA)和rho型谷胱甘肽S-转移酶(GSTR)、热休克蛋白70 (HSP70)、alpha 1型钠钾ATP酶(ATP1A1)及β-肌动蛋白(beta-actin, ACT)基因cDNA核心序列，序列分别长879 bp、582 bp、588 bp、660 bp、749 bp和554 bp。序列同源性分析发现，属鲈形目的黄斑篮子鱼CYP1A、GSTA和GSTR与同属鲈形目的牙鲆Paralichthys olivaceus、欧洲鲽Pleuronectes platessa、真鲷Pagrus major、鲤形目的斑马鱼Brachydanio rerio 相应氨基酸序列同源性较高，CYP1A和GSTA与非洲爪蟾(两栖类)、鸡(鸟类)、小鼠、大鼠和人(哺乳类)相应氨基酸序列同源性低，这可能与鱼类I、II时相去毒酶基因承担水环境毒素去毒代谢的特殊功能有关；而HSP70、ATP1A和β-肌动蛋白在鱼类、两栖类、鸟类、哺乳类中均有较高的同源性，这可能与这些基因在机体中承担的最基本的生命功能相关。应用半定量RT-PCR的方法，以β-肌动蛋白作为外参照，在指数期增长范围内分别得到了CYP1A、GSTA、GSTR、HSP70和ATP1A1 mRNA与β-肌动蛋白mRNA (%)的比值，确定黄斑篮子鱼肝脏去毒相关基因的组成型表达水平。其中，黄斑篮子鱼肝脏CYP1A、GSTA和GSTR基因组成型表达相对较高，HSP70和ATP1A1基因组成型表达相对较低，这可能与不同基因在黄斑篮子鱼海洋藻毒素去毒分子机理中承担的作用相关，为海洋藻毒素在海洋鱼类中的积聚及代谢去毒分子机制的研究提供了相关数据。  相似文献   

Water level variations in the Neuse and Pamlico Estuaries,North Carolina due to local and remote forcing     

Robert E. Reed  David A. Dickey  JoAnn M. Burkholder  Carol A. Kinder  Cavell Brownie 《Estuarine, Coastal and Shelf Science》2008

Water level time series records from the Neuse and Pamlico River Estuaries were statistically compared to local and distant wind field data, water level records within the Pamlico Sound and also coastal ocean sites to determine the relative contribution of each time series to water levels in the Neuse and Pamlico Estuaries. The objectives of this study were to examine these time series data using various statistical methods (i.e. autoregressive, empirical orthogonal function analysis (EOF), exploratory data analysis (EDA)) to determine short- and long-time-scale variability, and to develop predictive statistical models that can be used to estimate past water level fluctuations in both the Neuse Estuary (NE) and Pamlico Estuary (PE). Short- and long-time-scale similarities were observed in all time series of estuarine, Pamlico Sound and subtidal coastal ocean water level and wind component data, due to events (nor'easters, fronts and tropical systems) and seasonality. Empirical orthogonal function analyses revealed a strong coastal ocean and wind field contribution to water level in the NE and PE. Approximately 95% of the variation was captured in the first two EOF components for water level data from the NE, sound and coastal ocean, and 70% for the PE, sound and coastal ocean. Spectral density plots revealed strong diurnal signals in both wind and water level data, and a strong cross correlation and coherency between the NE water level and the North/South wind component. There was good agreement between data and predictions using autoregressive statistical models for the NE (R² = 0.92) and PE (R² = 0.76). These methods also revealed significant autoregressive lags for the NE (days 1 and 3) and for the PE (days 1, 2 and 3). Significant departures from predictions are attributed to local meteorological and hydrological events. The autoregressive techniques showed significant predictive improvement over ordinary least squares methods. The results are considered within the context of providing long time-scale hindcast data for the two estuaries, and the importance of these data for multidisciplinary researchers and managers.  相似文献