Arbuscular mycorrhizal fungal colonization of GlycyrrhJza glabra roots enhances plant biomass,phosphorus uptake and concentration of root secondary metabolites

Arbuscular mycorrhizal(AM)fungi penetrate the cortical cells of the roots of vascular plants,and are widely distributed in soil.The formation of these symbiotic bodies accelerates the absorption and utilization of mineral elements,enhances plant resistance to stress,boosts the growth of plants,and increases the survival rate of transplanted seedlings.We studied the effects of various arbuscular mycorrhizae fungi on the growth and development of licorice(Glycyrrhiza glabra).Several species of AM,such as Glomus mosseae,Glomus intraradices,and a mixture of fungi(G.mosseae,G.intraradices,G.cladoideum,G.microagregatum,G.caledonium and G.etunicatum)were used in our study.Licorice growth rates were determined by measuring the colonization rate of the plants by the fungi,plant dry biomass,phosphorus concentration and concentration of secondary metabolites.We established two cloned strains of licorice,clone 3(C3)and clone 6(C6)to exclude the effect of genotypic variations.Our results showed that the AM fungi could in fact increase the leaf and root biomass,as well as the phosphorus concentration in each clone.Furthermore,AM fungi significantly increased the yield of certain secondary metabolites in clone 3.Our study clearly demonstrated that AM fungi play an important role in the enhancement of growth and development of licorice plants.There was also a significant improvement in the secondary metabolite content and yield of medicinal compounds from the roots.     

Magnetic resonance imaging provides spatial resolution of Chilling Injury in Micro-Tom tomato (Solanum lycopersicum L.) fruit

Magnetic resonance imaging (MRI) was used to monitor internal changes in harvested tomato (Solanum lycopersicum L. cv. Micro-Tom) fruit. Measurements of ethylene evolution, respiration, and ion leakage indicated that the fruit developed chilling injury (CI) after storage at 0 °C. Unlike these measurements, MRI provided spatially resolved data. The apparent diffusion coefficient (ADC), which is an indication of water mobility in tissues, was calculated from MRIs of the different parts of the fruit. Storage for 1 or 2 weeks at 0 °C caused no difference in the ADCs (D-values) in the pericarp, but it did lead to higher values in the inner tissues i.e., the columella and locular region compared to non-chilled fruit (P < 0.05). Changes in inner fruit D-values after 1 and 2 weeks of chilling at 0 °C were similar to changes in respiration, ethylene production and ion leakage which increased (P < 0.05) compared to the non-chilled controls. Most CI studies of tomato fruit used pericarp tissue. Our data indicate that columella tissue changes occur in response to chilling injury in tomato fruit and suggest that more caution is needed when interpreting data from experiments commonly used to study this phenomenon.     

基于高光谱成像的寒地水稻叶瘟病与缺氮识别

为进行水稻叶瘟病与养分缺失的区分、实现叶瘟病及时、准确的诊断,以大田试验为基础,利用高光谱成像仪获取2个品种的健康、缺氮、轻度感病和重度感病共4类水稻叶片的反射率光谱,对其光谱特性进行分析,并采用多种预处理方法、分别结合偏最小二乘判别分析(partial least squares-discriminate analysis,PLS-DA)和主成分加支持向量机(principle component analysis-support vector machine,PCA-SVM)方法构建水稻叶瘟病识别模型。试验结果显示6个判别模型都获得了较高的识别准确率,经标准正态变量(standard normal variate,SNV)变换预处理的PLS-DA模型获得了最佳的识别结果,预测准确率达100%,经多元散射校正(multiplicative scatter correction,MSC)预处理的PCA-SVM模型的预测准确率也达到97.5%。本研究为水稻叶瘟病的判别和分级提供了新方法,也为稻瘟病大范围遥感监测提供了基础。     

人外周血CD4+ T细胞F-actin的超分辨SIM成像

通过合成lifeact序列,将其克隆到pEGFP-C1载体上,构建了pEGFP-C1-Lifeact质粒,转染原代CD4+T细胞,实现对CD4+T细胞F-actin的荧光标记,结合超分辨3D-SIM荧光成像技术,研究人外周血CD4+T细胞F-actin的精细结构,并对其动力学过程进行连续观察。结果表明,CD4+T细胞F-actin分布在细胞膜周围,处于解聚和聚合的动态平衡状态,与普通荧光显微镜相比,超分辩SIM成像F-actin结构更加清晰,分辨率提高2~4倍。     

高光谱图像技术检测玉米种子真伪的研究进展

玉米种子真伪的检测是玉米种子在品种选育、种子检验、农业生产中的重要环节。随着图像技术和光谱信息的快速发展、高光谱成像系统硬件成本的降低以及性能的大大提升,高光谱图像技术在玉米种子真伪检测方面获得了更广泛的应用。为了能及时利用国内外的最新研究成果,从高光谱图像技术在玉米种子真伪检测方面综述了玉米种子及其他作物种子类型真伪检测的研究进展,并对其未来的发展方向进行了讨论和展望。     

基于主成分分析法的中国农村医疗保障条件研究

为测算出中国农村医疗保障条件的具体水平,并为其建设以及农村医疗保障水平的提高提供参考建议,研究通过主成分分析法从农村医疗条件衡量指标群中提取得到其主要影响因子,并对其进行了分类解释,最终得到测评农村医疗条件的综合指标体系。实证结果表明,选取的指标间具有较强的相关性,且对医疗条件具有较强的代表性,中国现有农村医疗条件的综合指标水平均值为364154.36,仅略高于新农合所能提供的最高医疗条件。这表明,中国农村医疗保障条件水平不高,且主要依靠新农合的发展建设。造成这种现象的原因是由于政府拨款的减少以及医疗机构自身的因素限制。同时,农村社会的建设情况、居民的收入、医疗行为、保险意识也间接影响着农村医疗保障条件的建设。最后结合农村社会的现实情况及居民医疗行为,从加强农村经济建设、加大政府扶持力度、建立农村医疗管理体系以及推进新农合进程等4个方面提出了相关建议。     

问题引导式教学法在医学史课程教学改革中的实践与思考

在医学史课程教学改革中应用问题引导式数学（Problem-Based Learning,PBL）,以专题重新组织教材内容,以问题引导教学,开展师生互换型教学和学生参与体验型教学,教考分离,旨在提高课程教学水平,使其从知识性课程提升为知识与思辨相结合的课程,使学生通过医学史课程知史、思史、明史。     

红外热成像技术在作物胁迫检测方面的应用

红外热成像技术是通过接收事物自身的分子及原子无规则运动产生的热辐射后,对事物进行成像的一种机器视觉技术。目前,国内外均在红外热成像方面做了较深入的理论方法研究。为此,简要地概括了红外热成像技术的原理,介绍了该技术在农业上的应用,并从作物病害胁迫检测、水分胁迫分析、冻害胁迫分析3个方面,具体说明了红外热成像技术在作物胁迫检测方面的研究现状。最后,通过总结热红外技术的特点及优势,对未来该技术在作物检测方面的研究方向进行了展望。