不结球白菜小孢子胚胎发生过程及发育途径研究

采用FDA荧光染色法对小孢子游离培养的发育过程进行了观察。结果表明:不结球白菜花粉母细胞减数分裂释放出的小孢子发育到单核靠边期及稍后时期染色最深、活力最强。多数游离小孢子培养经历的发育过程与合子胚相似,并且胚胎发育迅速,6～9 d产生大量球型胚,13 d开始出现子叶型胚胎。小孢子胚胎发育途径既有对称分裂并产生胚胎的途径(B途径),也有第1次不对称有丝分裂的方式;第1次不对称分裂后,既有营养细胞单独发育成胚的现象(A途径),也有营养细胞和生殖细胞共同发育成胚的现象(E途径),但未发现生殖细胞单独发育成胚的现象。     

Probability Statistics and Sensitivity Analysis of Parameters of Soil-Water Characteristic Curves

To study the characteristic of soil-water characteristic curves (SWCC) of several different types of soils, a number of data sets of matric suction-volume water content were studied for UNSODA clay, UNSODA sand, Guangxi expansive soil and Hefei expansive soil. Three types of Fredlund-Xing models and three types of van Genuchten models were used to study the influence of SWCC models, and three types of functions in the scientific programming language MATLAB were applied to analyze the effect of different fitting methods. Through the data fitting and statistic analysis, the probabilistic characteristics of the fitting parameters of SWCCs for the four types of soils were obtained. For analyzing the relative sensitivity of the normalized volume water content to the three fitting parameters of SWCC, a formula which considers the correlation of parameters was proposed. Through the data fitting of many data sets, it is found that the fitting methods influence the value of parameters of SWCC, while the influence is less than that of fitting models from the statistical point of view. The SWCCs of all the models are nearly the same when the suction is low. With the increase of the suction, the SWCCs of FX2 and VG2 are very close, and the SWCCs of FX3 and VG3 are the same. The sensitivity analysis shows that the normalized volume water content is more sensitive to parameters n and m than to parameter a.     

Test Method of Indoor Noise for Micro-surfacing Mix

Micro-surfacing mix has been wildly used in the pavement maintenance for its water proofing, anti-skidding and wear resistance. However, micro-surfacing pavement has higher noise than the common asphalt pavement and its noise can not be measured effectively and accurately. Therefore, the indoor noise test method of micro-surfacing mix based on wet track abrasion test was explored. The micro-surfacing mix specimens were used to imitate the micro-surfacing pavement. The wet track abrasion tester was used to provide the vehicle loads. The sound level meter was used to measure the noise between tire and pavement. Furthermore, the indoor noise of nine kinds of micro-surfacing mixes with different gradation was examined. The results show that the equivalent sound level in the second time period has good relationship with the surface texture depth by sad patch method. Then the test method and test procedure for the indoor noise of micro-surfacing mix based on wet track abrasion test were given. Finally, two micro-surfacing mixtures with different gradations were made to validate the test method. The results show that the evaluation method can effectively distinguish the difference of micro-surfacing mixes with different gradation and can supplement the mix design method of micro-surfacing mixes.     

不结球白菜种质资源的研究与利用

系统总结了南京农业大学近60年来进行不结球白菜种质资源的研究与利用的进展。从研究方法,种质资源的调查、搜集和整理,形态学的观察研究,生物学特性的研究,园艺学分类法的提出,抗性鉴定与分析,主要经济性状的遗传动态,种质资源遗传多样性分析与核心种质构建,种质资源的利用等方面,论述了不结球白菜种质资源研究所取得的成果,并对该项研究进行了展望。     

芎麻汤及其提取物对利血平低5-HT型偏头痛模型小鼠的影响

目的探讨芎麻汤及其提取物对利血平所致低5-HT型偏头痛小鼠的作用机制,初步筛选芎麻汤的有效部位。方法采用皮下注射利血平(1 mg/kg)14 d复制偏头痛模型,观察芎麻汤及其提取物对利血平偏头痛小鼠体质量、凝血时间及血浆中5-HT、NO含量的影响。结果芎麻汤、芎麻汤正丁醇提取物组能增加偏头痛小鼠的体质量,调节5-HT的过度降低;芎麻汤、芎麻汤正丁醇提取物、芎麻汤乙酸乙酯提取物组能延长偏头痛小鼠的凝血时间,提高血浆中NO的含量,与模型组比较,差异具有统计学意义(P<0.01)。结论芎麻汤及其乙酸乙酯提取物、正丁醇提取物具有治疗利血平所致小鼠偏头痛的作用。     

黄色线辣椒为母本的F_1代遗传特性与杂种优势研究

以1份黄色线辣椒材料为母本,10份红色线辣椒为父本,采用顶交法配制10个杂交组合,研究了果实成熟色和8个农艺性状的杂种优势和配合力。结果表明:所有F1代果实成熟色均表现红色,红色果实成熟色相对黄色而言为显性效应;F1代除开展度外各性状均表现出正向优势,具有较高的超中亲、超高亲以及超标优势;一般配合力效应值与杂种优势表现呈正相关,Gx07-06、05991-1、xhB、07-09、05-17产量性状一般配合力相对较高,参与组配的组合为强优势组合,超标优势30%,Gx07-06、05991-1超标优势分别达到75%和56%,为高产优质亲本;可利用此类亲本组配高原环境气候下高产线辣椒品种。     

Rheological properties and hemoglobin structure of red blood cells in cri-tically ill patients with coronary heart disease

AIM: To study the rheological properties of red blood cells (RBC) and the structure of hemoglobin in critically ill patients with coronary heart disease. METHODS: At pH 7.4, the rheological properties of RBC and the structure of hemoglobin isolated from critically ill patients with coronary heart disease and from healthy people were studied with both static and dynamic imaging techniques and ultraviolet-visible spectroscopy. RESULTS: The rheological properties of RBC from the critically ill patients with coronary heart disease were significantly different from those of healthy people. The bending modulus, which indicates the rigidity of RBC, was greater in the patients than that in healthy people. The absorption spectra of the hemoglobin of critically ill patients with coronary heart disease were almost the same as those of healthy people. CONCLUSION: The morphology and flexibility of RBC in critically ill patients with coronary heart disease are worse than those in healthy people, whereas the structure of hemoglobin in the patients is basically found no difference from that in healthy people.     

竹重组材微晶结构的X射线衍射分析

运用X射线衍射分析(XRD)的检测手段,对冷压热固化与热压法两种生产模式的竹重组材试样进行分析,结果表明竹材纤维素是以微晶结构为基础的无定型结构,仅在衍射角2θ为22.5°附近出现较突出的晶体衍射峰,在衍射角16.7°、35°附近出现对应强度较弱的晶体衍射峰。冷压热固化与热压过程中,竹材纤维素结晶区主体结构未见明显变化,但相对结晶度有不同程度下降,对竹重组材的物理力学性能有所影响。     

抗生素对农杆菌的抑菌效果及对黄花苜蓿愈伤组织诱导和分化的影响

研究了不同浓度抗生素对农杆菌抑菌效果及对野生黄花苜蓿愈伤组织诱导和分化的影响。结果表明:氨苄青霉素(Amp)的抑菌效果优于头孢霉素(Cef);各个浓度下的Amp和Cef对愈伤组织的诱导与对照相比基本无显著差异;Amp浓度为100～300mg/L,Cef浓度为200～500mg/L时对不定芽的形成具有较好的促进作用。因此,在进行农杆菌介导黄花苜蓿遗传转化研究时,可选择Amp作为抑菌剂,最佳浓度为300mg/L;Kan和Hyg作为抗性愈伤选择剂,适宜的浓度分别为40～50mg/L和15～20mg/L。     

生态条件的多样性变化对蜜蜂生存的影响

蜜蜂在整个生态系统中起着重要的传花授粉作用,是生态链中不可或缺的物种.随着现代农业的发展,蜜蜂赖以生存的环境遭到破坏,继而引发蜜蜂数量大幅减少,影响了蜂种的生存与可持续发展.总结了近年来生态条件的变化,归纳了影响蜜蜂生存的主要因素,分析了蜜蜂生存艰难的原因,提出了蜜蜂生存的关键问题,并展望了未来维持蜜蜂强群的主要研究方向.