根癌农杆菌介导柱花草炭疽菌遗传转化体系的优化

选取含有氯嘧磺隆抗性标记的ILV1基因和报告基因GFP二元载体的农杆菌AGL-1,采用单因子和双因子方法研究根癌农杆菌AGL-1介导柱花草炭疽菌CH008转化过程中各主要因素对转化率的影响,优化构建ATMT转化柱花草胶孢炭疽菌体系条件,使转化效率达到300 ～400个转化子/106个炭疽孢子,即根癌农杆菌AGL-1浓度OD600=0.8,炭疽菌分生孢子浓度为1x106个/mL,AS浓度为100 μmol/L,诱导时间为6h,共培养温度和时间分别为25 ℃和4d.经PCR检测都有GFP片段,并能够表达绿色荧光蛋白.这为进一步开展炭疽菌对柱花草的致病机理研究提供了依据,优化转化体系有利于后续突变体库的扩大、筛选突变体和致病功能基因的研究.     

播前底墒对陇东旱塬冬小麦的效应研究

在陇东旱塬通过人工创造不同的播前底墒,测定冬小麦产量、水分利用效率、关键生育期光合生理指标、主要品质等指标,研究了播前底墒对旱地冬小麦的效应。结果表明,随着播前底墒的增加,冬小麦的产量、水分利用效率、光合速率、光合量子产量显著增加,营养品质、磨粉品质和面粉加工品质明显改善。光合速率和籽粒品质在中底墒时最佳,高底墒略有降低,但仍优于低底墒。     

The investigation of the interaction between 5-Iodouracil and human serum albumin by spectroscopic and modeling methods and determination of protein by synchronous fluorescence technique

The interaction of 5-Iodouracil with human serum albumin (HSA) was investigated in aqueous solution by fluorescence quenching spectrum in combination with UV absorption spectrum and modeling method. The quenching mechanism and binding characteristics of 5-Iodouracil with HSA were obtained from the fluorescence measurement. The binding constants were calculated according to the Lineweaver-Burk equation at different temperatures. And the thermodynamic parameters, enthalpy change (ΔH) and entropy change (ΔS), were calculated by thermodynamic equations. The results showed that the hydrophobic interaction played a major role in the binding of 5-Iodouracil with HSA. The binding distance was obtained according to Föster’s non-radiative energy transfer theory. The effect of some normal ions on the binding constants was discussed. Modeling method was applied to elucidate the interaction mode between 5-Iodouracil and HSA, which was agreed with the calculated result by thermodynamic method. Moreover, the synchronous fluorescence technique was successfully applied to quantify total protein in human body fluids including serum, urine, and saliva samples. The results showed that this method was stable, reliable, selective, sensitive, and practical for the determination of HSA.     

Effects of planting soybean in summer fallow on wheat grain yield,total N and Zn in grain and available N and Zn in soil on the Loess Plateau of China

Dryland wheat is the major contributor to wheat production in the world, where water deficiency and poor soil fertility are key factors limiting wheat grain yields and nutrient concentrations. A field experiment was carried out from June 2008 to June 2011 at Shilipu (latitude 35.12°N, longitude 107.45°E and altitude 1200 m above sea level) on the Loess Plateau (a typical dryland) in China, to investigate the effects of rotation with soybean (Glycine max) green manure (GM) on grain yield, total N and total Zn concentrations in subsequent wheat (Triticum aestivum L.), and on nitrate-N and available Zn in the soil. The benefits of crop rotation with soybean GM on wheat grain yields became more evident with time. In the second and third years, the grain yields of wheat rotated with soybean GM reached 4871 and 5089 kg ha⁻¹ at the 108 kg N ha⁻¹ rate. These yields were 21% and 12% higher than the highest yields of wheat under a fallow-winter wheat (FW) rotation. Rotation with soybean GM reduced the amount of N fertilizer required to obtain wheat grain yields and biomass levels similar to wheat grown in the FW rotation by 20–33%. In the first 2 years, average grain N concentrations over all N rates increased by 6% and 12%, and those of Zn increased by 26% and 14% under the soybean GM-winter wheat (SW) rotation, compared with the FW rotation. The increased grain N and Zn concentrations were found to be related to the increased concentrations of nitrate-N and available Zn in the soil, particularly at the sowing of winter wheat. However, grain N and Zn concentrations were not improved by rotation with soybean GM in the third year. This was attributed to the dilution effect caused by the more grain yield increase than its nutrient export. In conclusion, planting soybean for GM in fallow fields reduced the need for N fertilizer to enhance wheat yields in this dryland region. Change in wheat grain N and Zn concentrations was related to soil nutrient concentrations, and to the balance between increased grain yield and its nutrient export.     

姜黄素调控Notch1信号通路诱导结肠癌SW480细胞株凋亡

目的 从Notch1信号通路探讨姜黄素诱导结肠癌SW480细胞株凋亡的分子机制。方法 （1）利用流式细胞技术检测不同浓度姜黄素（0,7.5,15,30,60 μmol/L）处理结肠癌SW480株24 h和48 h后的细胞凋亡情况。（2）通过RT-PCR检测不同浓度姜黄素（0,7.5,15,30,60 μmol/L）处理结肠癌SW480细胞株24 h和48 h后,Notch1信号通路中膜受体基因Notch1及下游靶基因Hes-1 mRNA表达情况,观察姜黄素对Notch1信号通路中Notch1及Hes-1基因mRNA表达的影响。结果 （1）姜黄素能诱导结肠癌SW480细胞株凋亡;（2）姜黄素能一定程度上下调Notch1信号通路中Notch1及Hes-1基因mRNA的表达（P＜0.05）。结论 姜黄素能一定程度上诱导结肠癌SW480细胞株凋亡,这种对结肠癌SW480细胞毒性作用可能与调控Notch1信号通路中膜受体基因Notch1及下游靶基因Hes-1转录有关。     

Temporal changes in ascendance and in‐season exploitation of Atlantic salmon,Salmo salar,inferred by a video camera array

Abstract Weekly exploitation rates of Atlantic salmon, Salmo salar L., in the River Utsjoki, Finland, were estimated from catch reports during the 2003, 2004, 2006 and 2007 seasons, and recordings of all Atlantic salmon ascending the river using a submerged video camera array. In all years, mean weekly fishing mortality rates were significantly higher in June than July to August, with a falling trend throughout the fishing season. Owing to overlap in size between one‐sea‐winter (1SW) and multi‐sea‐winter (MSW) salmon, the estimated fishing mortality rates were based on all sea‐age categories combined. By the second week in June, 18.3–34.7% of large salmon (only MSW) had ascended, compared with 2.2–6.4% of small salmon (1SW and some MSW). Indirectly, the earlier start of ascent of large salmon to River Utsjoki indicated that in‐river fishing mortality of MSW salmon is higher than for 1SW salmon. A later opening of the fishing season may be used to reduce the in‐river fishing mortality, especially for the MSW component.     

基于多FPGA的片上网络模拟平台设计和实现

针对片上网络的设计和优化问题，提出了一种基于多FPGA的片上网络模拟平台结构，用于加速片上网络的功能验证和性能评估.通过层次化设计和分布式流量管理器等技术，有效地提高了系统的灵活性，加速了片上网络的设计空间搜索.实验结果表明，多FPGA模拟平台不仅相对于传统的软件仿真具有500~10 000倍的加速比，与其他片上网络模拟平台相比也具有明显的速度优势.