近50年来金沙江流域悬移质输沙特性研究

以金沙江流域直门达、屏山等水文站实测资料为依据,采用Manner-Kendall趋势检验、水文统计等方法对金沙江悬移质输沙特性进行了分析。结果显示:金沙江水沙分布具有明显的水沙异源特性,不同区域水沙模数差异较大。1998年前金沙江年径流量和年输沙量无明显趋势性变化,受人类活动影响较小;1998年后金沙江流域不同区域水沙变化差异明显,金沙江上游年输沙量呈增加趋势,金沙江中、下游呈减沙趋势,特别是进入21世纪后,减沙趋势更加明显。径流变化等自然因素、水利工程拦沙和水土流失治理等人工因素是主要原因。经估算,1998-2015年金沙江年均减沙9957万t,其中径流变化贡献率占18.9%,人类活动因素贡献率占81.1%。

三维模型有向三角面片链码压缩方法

首先提出一种适用于三角面片链码算法的改进MC规格化方法,使用单位为2的体素作为改进MC算法中的单位体素,并使用其中的27个顶点重新构建等值面,最终获取高质量的规格化三角网格模型。在新的规格化模型上提出一种新的面片遍历方式,在三角面片链码算法的基础上,采用优先遍历右连接面片原则,控制面片的遍历方向,该方法能够减少面片遍历次数,并且延长面片链码的平均长度。实验结果表明,采用新的规格化方法和新的遍历方法,压缩效果与原三角面片链码相比,具有明显的提升。

Occurrence and molecular characterization of Potato spindle tuber viroid(PSTVd) isolates from potato plants in North China

China is the largest potato producing country worldwide,with this crop representing the fourth largest staple food crop in China.However,the steady presence of Potato spindle tuber viroid（PSTVd） over the past five decades has a significant economic impact on potato production.To determine why PSTVd control measures have been ineffective in China,more than 1 000 seed potatoes collected between 2009 and 2014 were subjected to PSTVd detection at the Supervision and Testing Center for Virus-free Seed Potatoes Quality,Ministry of Agriculture,China.A high PSTVd infection rate（6.5%） was detected among these commercial seed potatoes.Some breeding lines of potato collected from 2012 to 2015 were also tested for PSTVd infection,revealing a high rate of PSTVd contamination in these potato propagation materials.Furthermore,comparison of the full-length sequences of 71 different Chinese PSTVd isolates revealed a total of 74 predominant PSTVd variants,which represented 42 different sequence variants of PSTVd.Comparative sequence analysis revealed 30 novel PSTVd sequence variants specific to China.Comprehensive phylogenetic analysis uncovered a close relationship between the Chinese PSTVd sequence variants and those isolated from Russia.It is worth noting that three intermediate strains and six mild strains were identified among these variants.These results have important implications for explaining the ineffective control of PSTVd in China and thus could serve as a basic reference for designing more effective measures to eliminate PSTVd from China in the future.

铜仁“油茶通”数据平台的构建与应用

针对铜仁市油茶产业发展中存在的问题,构建基于物联网和数据展示的应用平台——油茶通。系统应用物联网技术采集数据,对铜仁地区油茶种植、宣传等各种情况进行数据化管理,构建了油茶交易信息发布平台、油茶宣传管理平台、基于人工在线咨询与离线智能交流的油茶咨询交流平台。上述平台基于构建的铜仁油茶通微信公众号、微信小程序、PC端和移动端官网等应用,对铜仁地区的油茶产业信息化产生积极的影响。

Multiplex PCR System Optimization with Potato SSR Markers

Potato variety Kexin18 was used as testing materials in this research to study the influence on main components in multiplex PCR system, different primer ratios and annealing temperatures in SSR marker amplification. Concentration and gradient experiments for four components （enzyme, MgCl2, DNA template and dNTPs） in PCR system were used in the research with the concentration of the other component remained the same; the orthogonal design L9 （34） was applied in the optimization of four sets of primers （STM0014, Pat, SSI, and UGP） in the reaction system at three levels; the temperature gradient selection was used to find out the optimum annealing temperature for the primer. The optimized multiplex PCR system of potato SSR marker with a total volume of 20 μL ： 2.5 μL 25 mmol.L-1 MgCl2, 0.6 μL 10 mmol·L-1 dNTPs, 0.8 U Taq, 80 ng DNA template was ultimately established through the comparison and analysis of test results; the ratio of four pairs of 4 mmol. L1 primers was 2 ： 1 ： 2 ： 3, and the annealing temperature was 54.7℃. The optimized reaction system could be repeated stably; and the stable and reliable amplification results were able to clearly distinguish different potato varieties. This research built the solid foundation for the further study of genetic diversity of potato germplasms and construction of DNA fingerprinting..

表演驱动的三维表情动画技术综述

表演驱动是三维表情动画技术的主流实现方法。以表演驱动的三维表情动画技术实现过程为主线,分别从三维人脸表情捕捉方法与表情分析、人脸表情模型生成算法与生成效果、三维表情动画实现过程与实现效果分析,论述了表演驱动的三维表情动画技术的发展历程及遇到的问题。最后论述了未来三维表情动画技术的发展方向。