Comparison of ciliature microtubule organelles in three hypotrichous ciliate species

We examined the structure and spatial organization of ciliature base-associated microtubules (BAM) in three hypotrichous ciliates (Stylonychia mytilus, Pseudourostyla cristata, Euplotes woodruffi) in fluorescence microscopy. The results revealed that BAM, including the anterior (ALM), posterior longitudinal microtubule (PLM) and the transverse microtubule (TM) bands, are composed of tubulin. The respective microtubular bands have cytoplasmic polarization patterns that are significantly asymmetric. The BAM of the midventral files in P. cristata appear cord-shaped compared with the ALM bands of transverse cirri in both S. mytilus and E. woodruffi, which extend to the left anterior side of the cell before converging. The TM bands of the left marginal cirri (MC) in S. mytilus extend to the right side of the cell, while those of the right MC bands extend to the left. Our observations suggest that BAM traits are common in hypotrichous ciliates even though different species possess different microtubule arrangements related to the conserved cirral morphogenetic patterns in the respective species. The differing development of BAM in the three ciliate suggests that the microtubules may be conserved in different hypotrichs. We have also demonstrated that the BAM, which appear polar and asymmetric, are localized in specific cytoskeletal positions and extend in different orientations within the cortex to connect with other ciliature-associated structures and, thus, strengthen the cortex. These BAM features indicate that they are directly associated with cell motion.     

利用GVG线采样技术提取农作物种植面积及其精度分析

GVG(GIS&Video&GPS)线采样系统提出以线状样区代替以往成数抽样中的点样区与面积样区概念,通过统计线状样区内作物种植面积成数来反映区域总体农作物种植面积成数。通过 GVG实地采样,将其结果与解译遥感影像提取的作物种植面积成数结果进行了对比分析,结果显示采用GVG线采样方式精确度较高,其采样系统具有实用性和推广价值。     

西北区域气象计量实验室综合能力比对结果分析

分析评价西北区域参加实验室比对的试验结果,及时发现问题并进行纠正,总结实施实验间比对工作的经验,提高实验室检定/校准能力和质量管理水平。参加比对的计量检定实验室分别对气压、温度、湿度、风速比对样品进行比对试验,用归一化偏差(En)进行统计分析。2011年西北区域气象计量检定的温度、湿度、气压实验室比对结果为满意,风速实验室比对结果为较满意。该次比对的实验数据客观、真实、可信,是对各参加比对实验室检定/校准能力的综合评价,较为客观地反映了各技术机构检定装置的测量能力、检定人员的技术水平以及西北区域气象计量标准装置的现状。     

Groundwater sustainability and groundwater/surface-water interaction in arid Dunhuang Basin,northwest China

The Dunhuang Basin, a typical inland basin in northwestern China, suffers a net loss of groundwater and the occasional disappearance of the Crescent Lake. Within this region, the groundwater/surface-water interactions are important for the sustainability of the groundwater resources. A three-dimensional transient groundwater flow model was established and calibrated using MODFLOW 2000, which was used to predict changes to these interactions once a water diversion project is completed. The simulated results indicate that introducing water from outside of the basin into the Shule and Danghe rivers could reverse the negative groundwater balance in the Basin. River-water/groundwater interactions control the groundwater hydrology, where river leakage to the groundwater in the Basin will increase from 3,114?×?10⁴ m³/year in 2017 to 11,875?×?10⁴ m³/year in 2021, and to 17,039?×?10⁴ m³/year in 2036. In comparison, groundwater discharge to the rivers will decrease from 3277?×?10⁴ m³/year in 2017 to 1857?×?10⁴ m³/year in 2021, and to 510?×?10⁴ m³/year by 2036; thus, the hydrology will switch from groundwater discharge to groundwater recharge after implementing the water diversion project. The simulation indicates that the increased net river infiltration due to the water diversion project will raise the water table and then effectively increasing the water level of the Crescent Lake, as the lake level is contiguous with the water table. However, the regional phreatic evaporation will be enhanced, which may intensify soil salinization in the Dunhuang Basin. These results can guide the water allocation scheme for the water diversion project to alleviate groundwater depletion and mitigate geo-environmental problem.     

秦山核电站邻近水域石油降解细菌的生态学研究

本文分析了1989年4月(春),7月(夏),10月(秋)和1990年1月(冬)秦山邻近水域表层水中石油降解细菌的丰度和分布规律,同时比较了温度、含油量、营养盐、溶解氧、盐度等环境因素对其数量变动的影响。分析结果发现,测区表层水中石油降解菌数量最高值达1.1×10~5个/dm~3,最低值为400个/dm~3,季节变化波动于97～4.9×10~4个/dm~3之间,菌量变化与水温,含油量呈正相关,与盐度呈负相关趋势,认为测区高营养盐、高溶解氧状况可能不成为石油降解细菌生长繁殖的限制因子,并指出测区低丰度的石油降解菌数量与该海区低水平的油污是一致的。     

基于遗传算法优化的支持向量机在岩性识别中的应用

为提高测井岩性识别的精度,本文结合乌夏地区岩芯资料和测井数据,总结该地区砂砾岩测井响应特征,优选出声波、自然伽马、密度、中子孔隙度和电阻率等5条测井曲线参数作为训练和测试样本,通过遗传算法挑选出最佳的支持向量机核函数参数σ和惩罚因子C,建立支持向量机岩性识别模型。结果表明该模型实际数据预测总体符合率为81.6%,在识别准确率上与传统测井识别砂砾岩岩性方法相比都有明显提升。     

Helmert方差分量估计在GPS/GLONASS/BDS组合定位权比确定中的应用

因GNSS系统间观测噪声、轨道精度的差异,采用经验权比进行组合定位难以得到最优结果。基于此,在GPS/GLONASS/BDS组合定位中引入Helmert方差分量估计,对GPS/GLONASS/BDS组合单点定位和基线解算中各系统观测值进行合理定权。实验表明,采用该方法确定的伪距观测值最佳权比为5∶1∶1,相位观测值最佳权比为1∶1∶1,有效提高了GPS/GLONASS/BDS组合定位的精度和可靠性。     

2020年6月26日新疆于田6.4级地震前中期和短期预测依据与启示

2020年6月26日新疆于田6.4级地震发生在2020年度全国地震危险区内,震前作出了较好的中期（年度）和短期（月尺度和周尺度）预测,是少有的地球物理观测能力较低地区的强震前中期和短临预测较好震例。本文梳理了中期和短期预测的主要依据及其预测效能,研究表明,震前中期异常主要有流动地磁、多方法组合、5.0级地震平静打破、6.0级地震的准周期活动等;短期异常有4.0级地震活动图像、中源地震影响、于田垂直摆倾斜EW、于田GNSS基准站EW位移、和田GNSS基准站EW位移等。在总结震前分析预测过程的基础上,提出针对地球物理观测密度低地区的地震危险区论证和短临跟踪的建议,为该类地区的地震危险区判定及跟踪工作提供宝贵经验。     

Wave Propagation Modeling and Amplitude-Variation-with-Offset Response in a Fractured Coalbed

Coalbed methane can be detected employing the amplitudevariation-with-offset technique. However, there are two issues in applying this technique to a coalbed: strong azimuthal anisotropy resulting from high-density fractures, and the seismic response being composed of many or several individual reflections within the coalbed. To overcome these difficulties, we present an exact solution for reflections in extensive dilatancy anisotropy media. First, we build a three-layer model and simulate the wave propagation in this model. Then we derive an exact P- and converted S-wave reflection coefficient equation based on boundary conditions. Finally, substituting given model parameters into the exact equation, we obtain the variation in the reflection coefficient with incidence angle. The results show that the fracture factors, wavelet frequency and thickness of the coalbed have different effects on the reflection coefficient. Furthermore, we create a synthetic seismogram by forward calculation, and the result fits well with results of the exact equation.     

基于沃尔什变换和高斯模型的测井曲线分层方法

在分析了单独利用沃尔什变换或高斯模型进行测井曲线自动分层优缺点的基础上,提出了一种沃尔什变换和高斯模型联合的测井曲线自动分层方法.该方法融合了沃尔什变换简单、快速的特点,同时又利用了高斯模型对沃尔什变换分层的边界进行校正,实现了测井曲线由粗到细的分层过程.实例应用表明,该方法能够利用多条测井曲线进行自动分层,效果良好,验证了模型的可靠性和实用性.