Environmental influences on temporal patterns of settlement in two littoral labrid fishes in the Mediterranean Sea

Correlations between daily fish settlement and environmental and physical parameters were examined during two consecutive years in two labrid species (Symphodus roissali and Symphodus ocellatus) in the NW Mediterranean Sea. Both these species have a short planktonic larval duration (12±0.3 and 9±0.4 days, respectively) and limited offshore larval dispersal. Time-series analysis was used to compare the daily settlement patterns with various environmental variables, and non-linear generalized additive models (GAM) were used to examine the relationship between environmental conditions averaged over larval period and daily settlement patterns. Settlement was not uniform and took place as pulses of different length. Although the analyses detected a few significant correlations between day-to-day patterns in environmental variables and settlement (e.g. solar radiation, atmospheric pressure, daytime or nocturnal wind components), these were not consistent among years. In S. ocellatus, however, wind components (daytime or nighttime) explained part of the variance in settlement intensity. The correlations (GAM outputs) observed between settlement patterns and environmental variables (averaged during the whole planktonic period) suggest that calm weather during the planktonic period usually increases settlement success.     

Using chemometrics to evaluate anthropogenic effects in Daya Bay, China

In this work, we have monitored 12 stations to study the effects caused by natural, marine and anthropogenic activities on water quality in Daya Bay, China. Results show that the N:P ratios are 71.54, 41.29, 81.50 and 98.27 in winter, spring, summer and autumn, respectively. Compared with the data of the past 20 years, the atomic N:P ratios have increased, indicating increased potential for P limitation; the atomic Si:N ratios have decreased; the nutrient structure has substantially changed over a period of 20 years. These findings show that the nutrient structure may be related to anthropogenic influence. The data matrix has been built according to the results, which were analyzed by principal component analysis (PCA). This analysis extracted the first four principal components (PC), explaining 73.58% of the total variance of the raw data. PC1 (25.53% of the variance) is associated with temperature, salinity and nitrate. PC2 (21.64% of the variance) is characterized by dissolved oxygen and silicate. PC3 (15.91% of the variance) participates mainly by nitrite (NO₂-N) and ammonia (NH₄-N). PC4 explaining 10.50% of the variance is mainly contributed by parameters of organic pollution (dissolved oxygen, 5-day biochemical oxygen demand and chemical oxygen demand).PCA has found the important factors that can describe the natural, marine and anthropogenic influences. Temperature and salinity are important indicators of natural and marine characters in this bay. The northeast monsoons from October to April and southwest monsoons from May to September have important effects on the waters in Daya Bay. It has been demonstrated that anthropogenic activities have significant influence on nitrogen form character. In spatial pattern, a marine aquaculture area and a non-aquaculture area are widely identified by the scores of stations. In seasonal pattern, dry and wet season characters have been demonstrated.     

对虾白斑综合症病毒基因组同源重复区结合蛋白的筛选

对对虾白斑综合症病毒（WSSV）基因组序列分析发现，基因组3％的区域均匀分布有与昆虫杆状病毒类似的9个同源重复区，很可能具有昆虫杆状病毒同源重复区参与病毒复制起始或转录调控的功能．以WSSV基因组同源重复区中一个包含高度保守结构域的小重复片断DNA（210bp）作为配体，利用WSSV基因组噬菌体展示库，经过5轮淘选出一个可与DNA特异结合的重组噬菌体克隆，包含的外源DNA片断长度为306bp．通过与WSSV基因组序列对比，发现该序列为WSSV的ORFs中wsv 021的5’端部分．推测wsv 021是一个可能与病毒复制或调控相关的重要功能基因．     

惠州西湖水环境信息管理系统的建立与应用

分析了水环境信息管理的研究现状和不足,在前人研究的基础上,以软件工程原理和系统工程分析法为指导,进行系统的分析、设计和系统体系结构的介绍。阐述了系统的各功能模块的实现,重点介绍了专题地图和富营养化综合评价模块的实现及其在实际水环境监测和决策中的应用。该研究的总结为:系统基于SuperMap Object组件技术、数据技术和数据挖掘技术,以Visual Basic为平台集成专业模型与GIS于一体,实现了模型辅助水环境的评价和决策,并以直观的图形界面显示,是一种有益尝试。     

Searching for novel CYP members using cDNA library from a minke whale liver

The contaminant-induced cytochrome P450 (CYP) members in minke whale (Balaenoptera acutorostrata) can be potential biomarkers of the contaminant exposure and toxic effects. In this study, we constructed a cDNA library from the liver of minke whale from the North Pacific, and further screened a total of 6930 clones randomly selected in the library for the isolation of cDNA clones encoding novel members of CYP superfamily. The screening revealed the isolation of six novel CYP cDNA clones that are classified into CYP1A, CYP2C, CYP2E, CYP3A, CYP4, and CYP4A subfamilies. The BLAST homology search using the partial cDNA fragments of four CYP subfamilies (CYP1A, CYP2C, CYP2E and CYP4A) demonstrated that the minke whale CYPs were most closely related to pig CYPs (81-91%). Identification of multiple CYP genes in marine mammal species such as minke whale will provide new insights into the metabolic or toxicological functions of individual CYP members.     

冲绳海槽岩浆源的三分量混合模型

综合分析了冲绳海槽玄武岩中微量元素的地球化学特征，发现最少要求三分量混合作用来解释其岩浆源成分，并通过最大方差因子分析估算了3个分量的贡献比例。亏损型地幔是海槽岩浆源的主体，但其中舍有富集型地幔的成分，尤其是海槽中部玄武岩岩浆源中这种富集型地幔成分的特征表现得更为明显。俯冲组分是岩浆源中的另一个主要成分，贡献量为20％左右，是造成海槽区玄武岩中Pb强烈富集的重要原因。     

CTD电控多瓶采水器中电磁式释放机构设计与试验

文章概述了用电磁方式控制采水器释放机构的可行性，介绍了释放机构的工作原理、结构和特点，给出了应用实例试验中的测量方法和结果。     

针对GF-1遥感影像的基于影像与基于辐射传输模型的两种交叉定标方法比较

"高分一号"配置了4台16m分辨率多光谱宽幅(WFV)相机,组合观测幅宽达到800km。为了将其应用于定量遥感,需要对其进行精确的辐射定标。目前针对高分一号卫星有两种交叉定标方法,都在传统方法的基础上进行了改进。一种是基于影像的交叉定标方法(image-based),另一种是基于辐射传输模型和二向反射分布函数的交叉定标方法(RTM-BRDF)。本文采用这两种方法对高分一号(GF-1)的4个相机进行辐射定标,并对这两种方法进行了对比分析,发现对于WFV2和WFV3这两个近似星下点成像相机,image-based方法可以得到精度较高的辐射定标系数,而对于WFV1和WFV4这两个非星下点成像相机来说,RTM-BRDF方法得到的定标系数精度较高。因此,最终将两种方法结合给出GF-1 4个相机最终的定标系数。     

基于方差分量估计的不同截止高度角下的组合单点定位

BDS/GPS/GLONASS组合系统定位时,由于系统间卫星测距精度的差异性,需要合理确定卫星间权比,Helmert方差分量估计常被用于确定不同类观测值间权比;而当观测值含有粗差时,Helmert方差分量估计定位结果容易被粗差污染或收敛失真,出现大的偏差。文中基于Helmert方差分量估计,引入等价权因子IGGIII函数,建立抗差Helmert方差分量估计权函数模型,对比分析其在低截止高度角10°、15°和20°下,在BDS/GPS/GLONASS组合系统定位中的应用及定位精度,并讨论分析在高截止高度角30°和40°下,组合系统和单系统BDS的定位精度。实验结果表明:当观测值无明显粗差时,Helmert方差分量估计和抗差分量估计的定位精度相当,略低于高度角权函数的定位结果,点位精度RMS优于2.5m;含粗差时,抗差解定位精度最高;当截止高度角为30°时,BDS单系统定位精度RMS优于5m,而组合系统RMS接近3m;为40°时,组合系统平面精度RMS优于2m,三维精度RMS优于6m,而单系统不能定位。