Effects of temperature and salinity on survival,growth and DNA methylation of juvenile Pacific abalone,Haliotis discus hannai Ino

Temperature and salinity are two of the most potent abiotic factors infl uencing marine mollusks.In this study,we investigated the individual and combined ef fects of temperature and salinity on the survival and growth of juvenile Pacifi c abalone,Haliotis discus hannai Ino,and also examined the DNA methylation alteration that may underpin the phenotypic variation of abalone exposed to dif ferent rearing conditions.The single-factor data showed that the suitable ranges of temperature and salinity were 16–28°C at a constant salinity of 32,and 24–40 at a constant temperature of 20°C,respectively.The two-factor data indicated that both survival and growth were signifi cantly af fected by temperature,salinity and their interaction.The optimal temperature-salinity combination for juveniles was 23–25°C and 30–36.To explore environment-induced DNA methylation alteration,the methylation-sensitive amplifi ed polymorphism(MSAP)technique was used to analyze the genomic methylation profi les of abalone reared in optimal and adverse conditions.Neither temperature nor salinity induced evident changes in the global methylation level,but 67 and 63 dif ferentially methylated loci were identifi ed in temperature and salinity treatments,respectively.The between-group eigen analysis also showed that both temperature and salinity could induce epigenetic dif ferentiation in H.discus hannai Ino.The results of our study provide optimal rearing conditions for juvenile H.discus hannai Ino,and represent the fi rst step toward revealing the epigenetic regulatory mechanism of abalone in response to thermal and salt stresses.     

Geothermal potential evaluation and development prioritization based on geochemistry of geothermal waters from Kangding area,western Sichuan,China

Kangding geothermal area is located in the western Sichuan, belonging to southeastern margin of Tibetan Plateau. Similar to world-renowned south Tibetan and western Yunnan geothermal belt, western Sichuan has intensive surface thermal manifestations including boiling and hot springs. The emerging temperature of thermal waters ranges from 47 to 79 °C with total dissolved solids lying between 899 and 2550 mg/L. δ²H–δ¹⁸O isotopes indicate a meteoric source for the thermal waters and a significant positive oxygen-18 shift in the southern region. It is suggested that southern thermal waters experienced stronger water–rock interaction and are closer to thermodynamic equilibrium, which is also proved by the water type classification. The reservoir temperature calculated by empirical and theoretical chemical thermometry is 180–225 °C for the north and 225–310 °C for the south. Evidences of hydrogeochemistry, stable isotopes, geothermometry and radiocarbon dating indicate that southern region of Kangding area shows greater geothermal potential than the northern region. In addition, based on the hydrogeochemical modeling of mineral saturation, underlying problem of scaling is likely to occur in the study area. According to the results of reservoir temperature, south Kangding sub-district has greater potential in geothermal power generation and development than northern Kangding. Therefore, further exploration and drilling work should give priority to the south Kangding area.     

Simulating research on pressure distribution of floor pore water based on fluid-solid coupling

In terms of the problem that deep coal resources are under the threats of high water pressure, it is necessary to further study the outburst mechanism of working face floor karst water from the view of studying varying patterns of rock mechanical parameters and confined water pressure distribution of floor rock under the mining influence in the process of mining. Through the theoretical research of fluid-solid coupling and rock seepage experiment, the changing rule of the rock porosity and the Young’s modulus is analyzed, the changing law of the floor displacement is obtained by establishing the floor mechanic model, and the relation between elastic energy density and rock mass unit strain is established. Based on the numerical model of fluid-solid coupling analysis by the Comsol Multiphysics software, the changing law of floor displacement corresponds to the theoretical solution, the different variation laws of rock mass of different depths under the actions of ground pressure are acquired by simulation calculation, the distribution characteristics of pore water pressure are discussed, and the elastic energy density of the rock mass under the action of imbalance water pressure before and after mining is comparatively analyzed. Studies show that the distribution of pore water pressure is horizontally different before and after the stress peak line, and it mainly has four distribution patterns vertically. When mining above the confined water, the spatiotemporal position when and where the upper and lower boundaries of the rock mass in the lower water-resisting layer release energy at the same time is critical to the occurrence of water inrush.     

Distribution and source of heavy metals in the surface sediments from the near-shore area,north Jiangsu Province,China

Samples of surface sediment and vibrocore were collected in the near-shore area of north Jiangsu Province for grain size, elements, ²¹⁰Pb_excess and ¹³⁷Cs analyses. In our study area, the diversity of metal concentration was controlled not by the grain size, but by the source. The element content of the old Yellow River Delta was used as baseline for our study area. Geoaccumulation indexes indicate that no station was polluted by Cu, Pb, Zn and As, but the I_geo values of As were close to zero in some stations. Slight pollution caused by Cd was observed in some stations. Correlation and enrichment factors suggest that Cu, Pb and Zn are lithogenic in origin, while As and Cd are mixed in origin. Especially, in some polluted stations Cd was obviously anthropogenic in origin.     

龙门山和成都地震构造区的划分

新编制的地震动参数区划图采用了潜在震源区三级划分方案,以体现背景地震活动空间分布的不均匀性,并在地震构造区内归纳出统一的地震构造模型.本文根据西南地区潜在震源区三级划分的成果,分析了龙门山地震统计区内的龙门山和成都地震构造区的基本特征,历史地震活动强度及频度,主要活动构造的构造变形样式,建立了地震构造区的发震构造模型,确定了构造区的本底地震及划分构造源的地震构造标志.同时,提出了确定背景源空间分布函数的简单方法.     

A model for retrieval of dual linear polarization radar fields from model simulation outputs

An algorithm for retrieving polarimetric variables from numerical model fields is developed. By using this technique, radar reflectivity at horizontal polarization~ differential reflectivity, specific differential phase shift and correlation coefficients between the horizontal and vertical polarization signals at zero lag can be derived from rain, snow and hail contents of numerical model outputs. Effects of environmental temperature and the melting process on polarimetric variables are considered in the algorithm. The algorithm is applied to the Advanced Regional Prediction System （ARPS） model simulation results for a hail storm. The spatial distributions of the derived parameters are reasonable when compared with observational knowledge. This work provides a forward model for assimilation of dual linear polarization radar data into a mesoscale model.     

鲁西隆起区奥陶系碳酸盐岩成岩作用及其对储集性的控制作用

以鲁西隆起区奥陶系碳酸盐岩沉积旋回与不整合面分析为基础, 应用薄片、铸体和阴极发光等室内分析技术, 对其成岩作用、成岩序列、孔隙演化及其特征进行了详细研究。研究区的成岩作用分为两类: 建设性成岩作用和破坏性成岩作用, 前者包括白云石化、压溶、去石膏化、溶蚀和破裂等作用; 后者以重结晶、胶结、压实、硅化和充填作用为主。奥陶系碳酸盐岩经历了多期次和多种类型的成岩作用演化, 与马家沟组相比, 三山子组多经历了一次其沉积后的短期表生和随后的埋藏作用。三山子组白云岩、马家沟组东黄山段、土峪段和阁庄段粉细晶白云岩以及八陡段不整合面以下的溶蚀角砾岩段发育次生孔洞缝系统, 是较为有利的储集层段。     

Prevalence and diversity of norovirus genogroups I and II in Hong Kong marine waters and detection by real-time PCR

Marine waters from six sites around Hong Kong with varying levels of sewage pollution were examined for noroviruses (NoVs) by PCR cloning and sequencing of a highly-variable N-terminal region of the VP1 capsid gene, at the ORF1-ORF2 junction of NoV. Phylogenetic analysis of genogroups GI- and GII-specific PCR clones obtained from different marine sites indicated that human NoV GI.1 and GII.4 strains are the most prevalent genotypes circulating in Hong Kong waters. GI- and GII-specific TaqMan-based real-time PCR assays targeting the ORF1-ORF2 junction of NoVs were used to quantify NoV particles in marine water samples in parallel with total Escherichia coli counts which were enumerated on TBX medium. No correlation of any significance between NoV and E. coli counts was observed which highlighted the inadequacy in using E. coli as a fecal indicator to predict the level of NoVs in marine waters to protect public health.     

压缩感知技术在地震数据重建中的应用

地震资料室内处理过程要求野外采集的地震资料越多越好, 而地震数据远距离快速传输又要求野外地震数据量越少越好． 为解决这一矛盾, 将基于曲波变换与压缩感知的数据重建技术引入到地震资料处理中, 对实际的野外不完整数据进行压缩重建． 结果表明, 曲波变换相对于傅里叶变换在数据压缩采样方法中占有一定的优势． 但是, 在对实际资料进行处理时, 首先要对资料中的面波进行处理, 同时还要在一定曲波基元尺寸的情况下, 考虑缺失道数量的影响． 最终, 得到的重建数据图像纹理清晰、 连接自然, 从而验证了该方法的实用性和有效性．      

Evaluation of earthquake signal characteristics for early warning

This paper evaluates different characteristics for earthquake early warning.The scaling relationships between magnitude,epicenter distance and calculated parameters are derived from earthquake event data from USGS.The standard STA/LTA method is modified by adding two new parameters to eliminate the effects of the spike-type noise and small pulsetype noise ahead of the onset of the P-wave.After the detection of the P-wave,the algorithm extracts 12 kinds of parameters from the first 3 seconds of the P-wave.Then stepwise regression analysis of these parameters is performed to estimate the epicentral distance and magnitude.Six different parameters are selected to estimate the epicentral distance,and the median error for all 419 estimates is 16.5 km.Four parameters are optimally combined to estimate the magnitude,and the mean error for all events is 0.0 magnitude units,with a standard deviation of 0.5.Finally,based on the estimation results,additional work is proposed to improve the accuracy of the results.