1LQ-40型开沟扶垄犁性能试验研究

秸秆整秆还田覆膜技术是实施土壤保护性耕作的重要措施之一,对解决北方旱区蓄水保墒,促进历史增产增收具有重要意义.1LQ-40型开沟扶垄犁是专为实施秸秆整秆还田覆膜技术所研制的机具.为此,通过对1LQ-40型开沟扶垄犁田间开沟作业的正交试验,研究该机具的作业性能和工作质量.结果表明:开沟深度、机器前进速度和开沟角度对开沟阻力有显著影响,为开沟机具的研究提供一定的依据.     

畜禽场球顶式沼气反应器设计系统的构建研究

在总结和构建了球顶式沼气反应器设计系统模型的基础上,采用面向对象的软件设计方法,将设计过程中各阶段的计算模型进行模块化分类,并植入软件,建立计算推理框架.软件将知识库与数据库关联,通过对条件参数的归纳整理和对数据库参数的调用,利用推理计算模型进行推理计算,实现了对畜禽场球顶式沼气反应器最终设计结果的推算和稳定性校核.畜禽场球顶式沼气反应器设计系统的研究和构建,提高了设计人员的工作效率,并使计算结果更加准确可靠.     

基于DPSA方法的江都四站单机组优化运行

提出了考虑峰谷电价与水位变幅等因素的水泵叶片全调节与变频变速组合优化（以下简称组合优化）运行的动态规划数学模型,以日开机运行总耗电费用最小为目标函数,各时段水泵开机的叶片安放角和机组转速为决策变量,规定时段内抽水总量为约束条件,通过动态规划逐次逼近法（即DPSA）确定最优解.以江都四站为例,对单机组组合优化运行与定桨恒速运行进行了比较分析.结果表明,在典型潮位过程（12月至2月份平均潮位过程）,设计日均扬程（7.8~3.8 m）,机组以100%,80%和60%总水量（机组额定运行时的水量）作为约束时,组合运行优化结果与定桨恒速运行相比,考虑峰谷电价时可节省电费0.99%~35.00%,不考虑峰谷电价时可节省电费0.26%~17.23%.优化效果良好,为南水北调泵站优化运行提供了新的思路.     

大套第三抽水站辅助设备能耗计算分析

为了解大型泵站辅助设备的能耗情况,以江苏省通榆河北延送水工程大套第三抽水站为例,介绍了大套第三抽水站辅助设备设置情况;通过分析各类辅助设备的运行情况,系统计算了辅助设备运行能耗,分析了各类辅助设备能耗的特点.结果表明,大套第三抽水站辅助设备耗能约占泵站总能耗的3.13%,其中,照明、清污和电机通风等能耗所占比例较大,各占辅助设备总能耗的1/3左右.成果可为大型泵站辅助设备的设计与节能提供参考.     

村庄政治视野下的农地制度构建考察——江西省仲村土地调整个案的研究

随着农村宗族的复兴与村级组织权威的弱化,影响农地制度的因素除政府、村级组织外,还有来自村社区内部其他力量.农地制度的形成实质是多种力量政治博弈的一种结果.为此,笔者建议,为缓解因农地调控引起的诸多社会矛盾,未来农地制度的构建需要考虑并协调好两个层面的关系:一是国家农地政策与村级组织对农地的调控权之间的关系;二是村级组织与村社区其他各种力量(如宗族等)之间的关系     

Putative Phosphatase UvPsr1 Is Required for Mycelial Growth,Conidiation, Stress Response and Pathogenicity in Ustilaginonidea virens

Ustilaginoidea virens is the causal agent of rice false smut, which can be a highly destructive disease of rice. The plasma membrane phosphatase Psr1 proteins, which act as a regulator of the salinity stress response in yeast, are widely distributed across fungi, but their functional characterization is sketchy. In this study, we characterized the functions of Psr1 protein, UvPsr1, in U. virens. Analyses of the ΔUvpsr1 and its complementation strain showed that UvPsr1 is required for normal mycelial growth, conidiation and tolerance to oxidative, osmotic and cell wall stresses. When rice panicles were inoculated with the ΔUvpsr1 strains, no symptoms of false smut disease developed, showing that UvPSR1 also contributes to the pathogenicity of the fungus. The deletion mutant of UvPSR1 also appeared to produce a smaller titer of toxic compounds able to inhibit elongation of the germinated seeds. In conclusion, our results indicated that UvPsr1 is a new pathogenic factor of U. virens.     

5种植物精油抑菌活性及其化学成分研究

从植物精油中寻找新型抑菌剂是植物化学研究的一个方向。本试验提取了丁香、八角、孜然、薄荷和生姜5种药食兼用植物的精油,采用抑制菌丝生长法和96孔板法测试了5种精油对8种植物病原真菌和5种细菌的抑菌活性。结果表明5种植物精油对测试真菌有不同程度的抑制作用,丁香的抑制作用最强,对梨黑星病菌的抑制作用最强,其IC_(50)为93.44 mg/L;5种植物精油对测试细菌的抑菌作用较弱,孜然和生姜精油对青枯菌的抑制最强,最小抑菌浓度(MIC)也仅为125 mg/L。采用气相色谱-质谱联用仪(GC-MS)分析了各精油的主要化学成分,八角主要成分为茴香脑(53.16%),薄荷主要成分为长叶薄荷酮(15.85%),丁香主要成分为丁子香酚(82.68%),生姜主要成分为香叶醛(16.80%),孜然主要成分为茴香甲醛(46.06%)。本研究结果表明丁香具有开发为新型植物源抑菌剂的潜力。     

Spatial fit between water quality policies and hydrologic ecosystem services in an urbanizing agricultural landscape

Context

Sustaining hydrologic ecosystem services is critical for human wellbeing but challenged by land use for agriculture and urban development. Water policy and management strive to safeguard hydrologic services, yet implementation is often fragmented. Understanding the spatial fit between water polices and hydrologic services is needed to assess the spatial targeting of policy portfolios at landscape scales.

Objectives

We investigated spatial fit between 30 different public water policies and four hydrologic services (surface and groundwater quality, freshwater supply, and flood regulation) in the Yahara Watershed (Wisconsin, USA)—a Midwestern landscape that typifies tensions between agriculture, urban development, and freshwater resources.

Methods

Spatial extent of water policy implementation was mapped, and indicators of hydrologic services were quantified for subwatersheds using empirical estimates and validated spatial models.

Results

We found a spatial misfit between the overall spatial implementation of water policy and regions of water quality concern, indicating a need for better targeting. Water quality policies can also be leveraged to protect other hydrologic services such as freshwater supply and flood regulation. Individual policy application areas varied substantially in their spatial congruence with each hydrologic service, indicating that not all services are protected by a single policy and highlighting the need for a broad spectrum of policies to sustain hydrologic services in diverse landscapes. We also identified where future policies could be targeted for improving hydrologic services.

Conclusions

Joint spatial analysis of policies and ecosystem services is effective for assessing spatial aspects of institutional fit, and provides a foundation for guiding future policy efforts.

     

昆虫细胞色素P450基因的表达与调控及P450介导抗性的分子机制

本文综述了在杀虫剂抗性中起重要作用的 P4 50酶系研究的最新进展。内容包括 :细胞色素 P4 50酶系基因及其基因的表达与调控 ,P4 50介导抗性的分子基础。细胞色素 P4 50表达表现出发育期、组织、品系特异性及可诱导性。 P4 50表达的调控机制复杂 ,可能受顺式调控元件 (如 CYP6 B1)或反式作用因子 (如CYP6 A1)或顺式、反式因子的共同调控 (如 CYP6 D1)。调控可能涉及转录增强的转录机制或 m RNA稳定性增加的转录后机制。 P4 50的超量表达是 P4 50酶系介导抗性的主要机制 ,P4 50的氨基酸替换也可能在杀虫剂抗性中起作用。     

西卡柱花草传粉受精过程花朵形态变化的研究

对西卡柱花草传粉受精过程花朵形态变化的研究结果表明,凌蛄３～６时,多数花蕾进行自花授粉,６～７时,花蕾完成自花授粉过程,此时萼管与花冠长度几乎相等。上竿８：３０～９：３０,小花开放但龙骨瓣仍闭合时,花粉粒在柱头上萌发。开共经骨瓣松开,露出雌雄蕊,花粉管穿过花柱道、子房内壁进入胚珠。花后６小时左右,小花关闭,合子及初生胚乳核中出现雄性核仁。小花开放过程中的形态变化可作为传粉、花粉萌发、受精作用的形态