General mechanisms of drought response and their application in drought resistance improvement in plants

Plants often encounter unfavorable environmental conditions because of their sessile lifestyle. These adverse factors greatly affect the geographic distribution of plants, as well as their growth and productivity. Drought stress is one of the premier limitations to global agricultural production due to the complexity of the water-limiting environment and changing climate. Plants have evolved a series of mechanisms at the morphological, physiological, biochemical, cellular, and molecular levels to overcome water deficit or drought stress conditions. The drought resistance of plants can be divided into four basic types-drought avoidance, drought tolerance, drought escape, and drought recovery. Various drought-related traits, including root traits, leaf traits, osmotic adjustment capabilities, water potential, ABA content, and stability of the cell membrane, have been used as indicators to evaluate the drought resistance of plants. In the last decade, scientists have investigated the genetic and molecular mechanisms of drought resistance to enhance the drought resistance of various crops, and significant progress has been made with regard to drought avoidance and drought tolerance. With increasing knowledge to comprehensively decipher the complicated mechanisms of drought resistance in model plants, it still remains an enormous challenge to develop water-saving and drought-resistant crops to cope with the water shortage and increasing demand for food production in the future.     

高职院校图书馆新生入馆教育工作创新研究

对几种新生入馆教育方式的优缺点进行了比较分析,以山东商务职业学院图书馆为例,详细介绍了宣传片拍摄要领及技巧,提出了一种综合性的新生入馆教育新模式.     

城市治理首要应加强市民的思想道德建设——以湛江市治理交通秩序为例

交通混乱既影响城市形象,又制约经济发展。本文通过对湛江市区交通混乱现象进行深入调查研究,认为要从根本上改变这一现状,取得长效成果,除了采取行政立法、经济处罚、改善交通基础设施等治理措施外,还应着重加强市民的道德建设,提高其思想道德素质,培养市民良好的社会道德行为习惯。文章旨在为加强湛江市民道德建设,解决湛江及其它城市突出交通问题提供参考。     

基于Android系统的斗地主游戏的设计与实现

随着智能手机的迅猛发展,Wi Fi的全民时代到来,手机网络游戏越来越得到人们的青睐.首先设计了基于Android系统的斗地主纸牌游戏的功能模块、类以及数据库,实现了客户端注册、登录、游戏房间选择、多人斗地主以及服务器端接收多个用户连接请求且管理用户信息功能,然后对该游戏中的关键技术进行了详细描述,最后展示了游戏的运行界面.测试效果表明,软件界面友好、操作便捷,能够满足手机用户对斗地主游戏的基本需求.     

数控车床加工椭圆类非圆曲线宏程序应用

为方便加工零件上不同位置的椭圆轮廓,采用坐标系平移与坐标系旋转的方法,将给定椭圆表达式所在的原坐标系与数控车床工件坐标系建立联系.并通过实例进行粗车循环与宏程序联合编程,完成零件加工.提出的坐标系平移与坐标系旋转方法,可方便地对不同位置的椭圆轮廓在数控车床工件坐标系中建立新的表达式,该方法数学计算简单,适用于各类、不同位置非圆曲线的宏程序编写.     

青藏铁路含保温夹层路基厚度与地温关系的研究

通过对青藏铁路风火山段含有保温夹层的路基建立均匀介质分层纯导热模型并运用分层近似解法求出冻土表层的温度函数,结合Lachenbruch给出的冻土层的理论温度表达式,得到了路基填料层、保温层、地表年平均温度与正弦变化温度的振幅比三者之间的隐式方程,并应用该方程对三者之间的关系进行了分析.     

重卡驱动桥壳疲劳稳健性与轻量化设计

驱动桥壳轻量化设计对于提高承载能力、降低生产成本具有重要的意义.本文在驱动桥壳有限元分析和疲劳分析计算的基础上建立驱动桥壳多目标优化模型，对重型卡车驱动桥壳进行参数化设计，建立正交试验表，利用田口方法和综合评价方法对驱动桥壳的疲劳性能稳健性和质量进行优化设计.优化结果表明，此方法可以应用于驱动桥壳的多目标优化，优化后驱动桥壳的疲劳稳健性能得到提高，减轻了质量，因此节约了桥壳材料，降低了生产和运营成本，提高了设计水平.     

Geochemistry of Clayey Aquitard Pore Water as Archive of Paleo-Environment,Western Bohai Bay

The record of paleo-environment in clayey aquitard pore water is much more effective relative to aquifer groundwater owing to the low permeability of clayey aquitard. Oxygen-18 (18O), deuterium (D), an...     

Optimal investment problem for an insurer and a reinsurer

This paper studies the optimal investment problem for an insurer and a reinsurer. The basic claim process is assumed to follow a Brownian motion with drift and the insurer can purchase proportional reinsurance from the reinsurer. The insurer and the reinsurer are allowed to invest in a risk-free asset and a risky asset. Moreover, the authors consider the correlation between the claim process and the price process of the risky asset. The authors ?rst study the optimization problem of maximizing the expected exponential utility of terminal wealth for the insurer. Then with the optimal reinsurance strategy chosen by the insurer, the authors consider two optimization problems for the reinsurer: The problem of maximizing the expected exponential utility of terminal wealth and the problem of minimizing the ruin probability. By solving the corresponding Hamilton-Jacobi-Bellman equations, the authors derive the optimal reinsurance and investment strategies, explicitly. Finally, the authors illustrate the equality of the reinsurer's optimal investment strategies under the two cases.     

兰州黄河岸边卵石层大吨位桩基自平衡法试验研究

对兰州深安黄河大桥进行桩基自平衡法试验。在对黄河岸边的岩土层进行桩基试验时,对桩基的极限侧阻力和端阻力标准值的取值提出建议,并在兰州地区进行自平衡法桩基试验时,对桩基侧摩阻力的取值提出建议。