沉淀法制备的紫杉醇白蛋白微粒包封率测定

采用沉淀法制备紫杉醇白蛋白微粒,采用高效液相色谱法(HPLC)测定紫杉醇质量浓度,以二氯甲烷为有机相,采用萃取法分离白蛋白微粒与游离药物,测定其包封率。结果表明:紫杉醇在10~100 mg·L-1范围内线性良好,平均回收率可达到97.6%~101.0%;有机溶剂萃取法测定紫杉醇白蛋白微粒包封率的平均回收率,达94.80%~101.67%。这种方法测定紫杉醇白蛋白微粒回收率准确可靠,适用于沉淀法制备的白蛋白微粒的包封率测定。     

500kV变电站直流系统组成及接地故障分析

直流系统对于保障变电站二次保护、智能终端等装置的正常运行至关重要,是影响电网设备安全运行的重要因素之一。一旦直流系统发生接地故障后,应立即找出直流系统的接地点,并尽快消除,否则会产生严重影响主设备的正常运行。针对直流系统接地故障的危害和故障点的查找方法进行了分析,并分析了相应的防范措施。     

Effect of Linc00152 targeting miR-376c-3p on viability,apoptosis and radiosensitivity of cervical cancer cells

AIM: To investigate the effect of Linc00152 on the viability, apoptosis and radiosensitivity of cervical cancer cells. METHODS: RT-qPCR was used to detect the expression levels of Linc00152 and microRNA-376c-3p(miR-376c-3p) in human cervical cancer HeLa cells and SiHa cells, and normal cervical Ect1/E6E7 cells. The cervical cancer HeLa cells with low Linc00152 expression or miR-376c-3p over-expression were established. MTT assay, flow cytometry, colony formation assay and Western blot were used to determine the cell viability, apoptosis, radiosensitivity and related protein expression. The dual-luciferase reporter assay was used to verify the regulatory relationship between Linc00152 and miR-376c-3p in the HeLa cells. RESULTS: Compared with the Ect1/E6E7 cells, Linc00152 was up-regulated in the HeLa cells and SiHa cells, and miR-376c-3p was down-regulated (P < 0.05). Low expression of Linc00152 or over-expression of miR-376c-3p inhibited the viability of HeLa cells, induced apoptosis, enhanced the radiosensitivity, inhibited the protein expression of cyclin D and Bcl-2, and promoted the protein expression of P21 and Bax (P < 0.05). Linc00152 negatively regulated miR-376c-3p expression in the HeLa cells, and inhibition of miR-376c-3p expression reversed the effect of low expression of Linc00152 on HeLa cell viability, apoptosis and radiosensitivity. CONCLUSION: Linc00152 is highly expressed in the cervical cancer cells. Linc00152 affects the viability, apoptosis and radiosensitivity of HeLa cells by targeting miR-376c-3p, which is a potential diagnosis and treatment target for cervical cancer.     

油菜精量集中排种器电驱控制系统设计与试验

为适应丘陵区油菜机械化精量播种要求,针对地轮驱动致使传动系统复杂或滑移影响播种精度的问题,设计了一种油菜电驱排种控制系统。该系统集成无线蓝牙传输模块、单片机模块和Android终端平台开发,采用优化PID算法,实现集排器转速随作业速度的同步控制和自动调节播种穴距。台架试验研究了油菜电驱排种控制系统的控制精度和排种性能,当集排器转速为10～55 r·min~(-1)时,实际转速与理论转速的平均偏差均小于1.5%,且转速的变异系数均小于2.0%,稳定性较好;当穴距和作业速度分别为60～180 mm和1.6～3.2 km·h~(-1)时,穴距均匀性变异系数均低于15.0%。该系统实现了集排器电驱条件下播种穴距的同步调节,为油菜轻简化精量播种机的排种控制系统设计提供了参考。     

江汉平原中山杉引种造林试验研究

通过在江汉平原开展中山杉6个品系的引种造林试验。结果表明,引进的6个品系中山杉无严重病虫害发生,各生长指标均大于池杉,11 a生中山杉平均胸径为17.61 cm、树高为11.06 m、材积为0.1297 m^3,表明中山杉在江汉平原的引种试验基本成功,其中中山杉502和中山杉118最为突出,适合在江汉平原推广造林,丰富江汉平原造林树种。     

Urban land-use impacts on composition and spatiotemporal variations in abundance and biomass of earthworm community

Soil fauna can sensitively respond to alterations in soil environment induced by land-use changes.However,little is known about the impact of urban land-use changes on earthworm communities.In this study,three land-use types(i.e.,forest,nursery and abandoned lands)were chosen to identify differences in diversity,abundance and biomass of earthworm community in Kunming City.Urban land-use had a pronounced difference in species composition,evenness and diversity of earthworm communities.Forest land had the highest density,biomass and diversity of the earthworm communities.Total abundance was dominated by endogeic species in nursery land(70%)and abandoned land(80%),whereas in the forest land,the earthworm community comprised epigeic,endogeic and anecic species.Temporal changes in earthworm density and biomass were also significantly affected by land-use change.Total density and biomass of earthworms in the forest and nursery lands were highest in September,but highest in the abandoned land in October.The influence of soil physicochemical properties on the earthworm density and biomass also varied with land-use types.Soil temperature significantly affected earthworm density and biomass in the three land-use types.Soil pH was positively correlated with earthworm biomass in the forest land,but negatively associated with earthworm density in the abandoned land.Soil organic matter was positively correlated only with density and biomass of earthworms in the nursery and abandoned lands.Our results suggest that the species composition,abundance and biomass of earthworm communities can be determined by the modification of soil properties associated with urban land-use type.     

工程设施技术在稻渔共作模式中的发展

稻渔共作模式是一种继承传统农业中遵循自然协调、绿色生态的农业发展理念并以现代农业技术为指导的生态循环农业模式，该模式具有稳粮、促渔、增收、提质、环境友好和可持续发展等多种生态系统功能，但缺乏稻田生态理论研究及新的生态管理技术，且基础设施不足，与种养技术匹配设施缺乏。工程设施技术属于稻渔共作模式配套技术，决定稻渔共作模式的发展潜力。目前工程设备设施在稻渔共作模式中的应用普及程度低，尚未开发出与稻渔共作模式特点相匹配的专用设备。结合稻渔共作模式的发展历史和水平，对配套工程设施技术的发展进行分析。      

Water and dye-free coloration of wool

A water and dye-free heat treatment method was used to color wool fibers. The heat effect changed wool fibers to different colors from white in a nitrogen atmosphere. The influences of heating temperature and time on the colors of wool were investigated and the mechanical property of colored wool fibers was evaluated. The color strength of wool fibers increased as heat treatment temperature and time increased. The tensile strength retention rate of wool fiber was relatively high (≥90 %) when the heat temperature was below 200 °C. The surface morphologies of wool fibers scarcely changed during the heat treatment. The carbon content of fibers was found to reduce by heat treatment, indicating oxidization of components in the wool fibers in the process of coloration. Heat treatment may provide a water and dye-free approach to color wool and other textile fibers, albeit within a limited color range.     

Integrated Evaluation and the Physiological and Biochemical Responses of Semi-Wild Cotton under Complex Salt-Alkali Stress

[Objective] The genetic diversity of semi-wild cotton was abundant, so more new elite resistant genes could be found and applied to improve the resistance of cotton. The aim of this study was to primarily study on the regulation of response to salt-alkali stress, explore the method of integrated evaluation and characterize the resistance of semi-wild cotton. [Method] Four semi-wild and two cultivated Gossypium hirsutum accessions were evaluated for phonotypical, physiological and biochemical traits under alkali-salt versus normal conditions in hydroponic solutions. The alkali-salt tolerance was determined based on principal component analysis, cluster analysis, correlation analysis, grey rational analysis and analysis of variance. [Result] On the basis of the overall results, the alkali-salt stress tolerance of the six accessions was ranked as: Marie-galante85 > Latifolium32 > CRI16 > CRI12 > Latifolium40 > Latifolium130. Roots were found to be the most important responsive systems to complex alkali-salt stress. At seedling growth stage, the active scavenging system played a crucial role in response to alkali-salt stress. In addition, the salt tolerant and salt sensitive accessions showed different response tends towards leaf peroxidase, root ascorbate peroxidase and root catalase within 48 h, suggesting the accessions have different levels of response to salt stress. [Conclusion]Our study identified the most alkali-salt tolerant accessions and provided basic concept of complex alkali-salt tolerance mechanism within cotton accessions. And, our study provided a simple and rapid, highly accurate and precise method for evaluating salt resistance of cotton, and proved that the balance of ROS system play an important role in response to salt-alkali stress. Hence, mining of salt tolerant genes from these accessions may facilitate the development of novel salt tolerant variety.