日光温室黄瓜地上部各器官生长的模拟模型研究   总被引：2，自引：0，他引：2  

史为民  陈青云  曲梅 《上海交通大学学报(农业科学版)》2008,26(5)

本文利用Riehards生长函数和植物干物质分配的汇强理论建立了黄瓜植株地上部单个器官生长和干物质分配模型,该模型采用了一种全局分配方案.把植株上所有器官置于同一条件下进行考虑,更加适用于模拟植物拓扑结构变化情况下的器官生长.模型在计算各个器官汇强时,对同类型但不同生长年龄器官的汇强用其潜在生长速率来表示,有着更为直接的生物学意义.并能够通过试验数据直接获取相关参数.文中用该模型模拟了坐果之前黄瓜植株干物质的分配情况.  相似文献   

干花制作工艺与保存方法综述     

陆琳  苏艳  张颢  王丽花  瞿素萍 《勤云标准版测试》2008,(10)

干花是利用自然植物材料通过物理或化学方法处理后形成的观赏花材.近年来由于其独特的形状和风韵,及造花的使用随意、保存持久的特点,日益受到人们的喜爱.中国具有丰富的干花原材料,原料来源广且花朵硕大、花型多姿、花色艳丽;同时,中国经过长期的市场开拓和所具生产成本较低的优势,使干花拥有了较强的市场竞争力.因此,通过了解干花工艺的制作和保存方法,为<干花>行业标准的制定做好前期工作基础.干花从制作工艺划分,主要有自然干燥法、常温压制法、沙(硼砂)干燥法等8种方法;保存方法需做到防潮和防褪色等6项措施.  相似文献   

孔雀石绿及其代谢物在大菱鲆肌肉中的消除规律     

曲志娜  李存金  赵思俊  路平  王玉东  谭维泉  孙晓亮  郑增忍 《勤云标准版测试》2008,(6)

研究孔雀石绿及其代谢物隐色孔雀石绿在大菱鲆肌肉组织内的残留消除规律。采用超高效液相色谱-串联质谱法,对用浓度为800ng/ml的孔雀石绿溶液药浴1h的大菱鲆进行连续采样监测。结果表明,孔雀石绿在大菱鲆的肌肉中代谢较快,其含量降至检测限以下需要20.3d,而其代谢物隐色孔雀石绿存留时间长,消除过程缓慢,需长达281.9～356.7d。  相似文献   

慢病毒载体介导成纤维细胞高效稳定表达绿色荧光蛋白     

曹鸿国  李运生  曲秀霞 《勤云标准版测试》2008,(7)

 试验尝试建立稳定表达外源基因的人成纤维细胞系。取成年男性包皮皮肤的皮下组织,分离培养人皮肤成纤维细胞,分别采用脂质体和慢病毒载体介导转染人皮肤成纤维细胞表达绿色荧光蛋白。结果显示,来自成年人包皮皮下组织的成纤维细胞呈梭形,具有快速的增殖和稳定的生长性能。脂质体介导转染的人皮肤成纤维细胞绿色荧光蛋白表达不稳定,阳性细胞表达率低,转染后的人成纤维细胞变得更为细长,细胞生长速度降低。慢病毒载体介导人皮肤成纤维细胞高效稳定表达绿色荧光蛋白,转染后细胞生长性能和形态没有变化,经过多次传代和冻存复苏对人皮肤成纤维细胞绿色荧光蛋白的表达没有影响,通过流式细胞仪对慢病毒介导表达绿色荧光蛋白的人皮肤成纤维细胞检测显示,绿色荧光蛋白表达阳性率为99.85%,并且表达绿色荧光蛋白的人皮肤成纤维细胞细胞均一程度为76.05%。试验证实了慢病毒载体能够高效稳定介导人皮肤成纤维细胞表达绿色荧光蛋白。  相似文献   

优质抗病陆地棉新品种——新棉144的选育及栽培技术     

庞金柱 《中国棉花》2008,35(11):35-36

介绍了新棉144的选育过程、特征特性、产量、纤维品质及栽培技术要点。  相似文献   

菊酯类农药对水田生物影响研究进展   总被引：5，自引：1，他引：4  

姜辉  林荣华  陶传江  刘亮  瞿唯钢 《农药科学与管理》2005,26(10):14-19

拟除虫菊酯类农药是一个重要的杀虫剂类别,对有害昆虫具有良好的触杀作用.但是,在中国一直被禁止应用于水田害虫防治.本文综述了菊酯类农药对各种水田生物的急性和慢性作用机制、影响因子,提出拟除虫菊酯类农药能否在水田应用需要进行深入系统的研究论证.  相似文献   

Formulation of a rational dosage regimen of ceftiofur hydrochloride oily suspension by pharmacokinetic-pharmacodynamic (PK-PD) model for treatment of swine Streptococcus suis infection     

Wanhe Luo  Dehai Wang  Hua Qin  Dongmei Chen  Yuanhu Pan  Wei Qu  Lingli Huang  Shuyu Xie 《Journal of veterinary science (Suw?n-si, Korea)》2021,22(6)

BackgroundOur previously prepared ceftiofur (CEF) hydrochloride oily suspension shows potential wide applications for controlling swine Streptococcus suis infections, while the irrational dose has not been formulated.ObjectivesThe rational dose regimens of CEF oily suspension against S. suis were systematically studied using a pharmacokinetic-pharmacodynamic model method.MethodsThe healthy and infected pigs were intramuscularly administered CEF hydrochloride oily suspension at a single dose of 5 mg/kg, and then the plasma and pulmonary epithelial lining fluid (PELF) were collected at different times. The minimum inhibitory concentration (MIC), minimal bactericidal concentration, mutant prevention concentration (MPC), post-antibiotic effect (PAE), and time-killing curves were determined. Subsequently, the area under the curve by the MIC (AUC_0–24h/MIC) values of desfuroylceftiofur (DFC) in the PELF was obtained by integrating in vivo pharmacokinetic data of the infected pigs and ex vivo pharmacodynamic data using the sigmoid E_max (Hill) equation. The dose was calculated based on the AUC_0–24h/MIC values for bacteriostatic action, bactericidal action, and bacterial elimination.ResultsThe peak concentration, the area under the concentration-time curve, and the time to peak for PELF''s DFC were 24.76 ± 0.92 µg/mL, 811.99 ± 54.70 μg·h/mL, and 8.00 h in healthy pigs, and 33.04 ± 0.99 µg/mL, 735.85 ± 26.20 μg·h/mL, and 8.00 h in infected pigs, respectively. The MIC of PELF''s DFC against S. suis strain was 0.25 µg/mL. There was strong concentration-dependent activity as determined by MPC, PAE, and the time-killing curves. The AUC_0–24h/MIC values of PELF''s DFC for bacteriostatic activity, bactericidal activity, and virtual eradication of bacteria were 6.54 h, 9.69 h, and 11.49 h, respectively. Thus, a dosage regimen of 1.94 mg/kg every 72 h could be sufficient to reach bactericidal activity.ConclusionsA rational dosage regimen was recommended, and it could assist in increasing the treatment effectiveness of CEF hydrochloride oily suspension against S. Suis infections.  相似文献   

基于Kinect v2传感器的果树枝干三维重建方法     

任栋宇  李晓娟  林涛  熊明明  许贞辉  崔高建 《农业机械学报》2022,53(S2):197-203

针对果树三维重构中存在建模精度低、成本高、拓扑结构差等问题,提出一种基于Kinect v2传感器的果树表型三维重建与骨架提取方法。首先,使用Kinect v2传感器采集不同视角下的果树点云数据;其次,对植株点云进行尺度不变特征变换的特征点检测,对关键点使用快速点特征直方图算法进行特征向量计算,通过随机抽样一致性方法提纯点云的初始位置,经初始变换后使用改进的迭代最近点算法进行精配准、拼接形成完整点云;最后,使用Delaunay三角剖分解构点云数据对缺失点云进行填充,使用Dijkstra最短路径算法对最小生成树进行求取,通过迭代去除冗余分量对骨架进行简化,使用圆柱拟合算法估算枝干骨架,将枝干骨架变为封闭凸包多面体,实现果树的枝干三维重建。实验结果表明：采用本文所提建模方法点云平均配准误差为0.52cm,枝干平均重构误差不超过3.52%,重建效果良好。研究成果可为果园评估作物状态、智能化修剪等研究提供数据支持。  相似文献   

Outbreak of a new alien invasive plant Salvia reflexa in north‐east China     

M N Shao  B Qu  B T Drew  C L Xiang  Q Miao  S H Luo 《Weed Research》2019,59(3):201-208

The establishment of invasive species is widely recognised as a pivotal issue in the preservation of biodiversity. Salvia reflexa, a species native to the south‐central United States and Mexico, has been widely introduced in Argentina, Australia, New Zealand and Japan. In China, the first population of this plant was found growing adjacent to a grain depot in Shahai village, Jianping County, Liaoning Province, on 25 July 2007. Since the grain depot imported foodstuffs from regions where the plant is native, we infer that S. reflexa was introduced into China via imported foodstuff in the early to mid‐2000s. Based on field observations, at least seven populations of this plant were observed in north‐east China. The plants displayed vigorous growth in midsummer and produced prolific seeds to overcome the cold environment in winter. Salvia reflexa occurred in both dense monocultures and in mixed stands with native plants. In order to validate a system for recognising and categorising non‐native plants in China, the Australian Weed Risk Assessment system was used to assess the invasiveness status of 19 exotic and 16 native plants in north‐east China. Salvia reflexa exhibited a high score of 10, suggesting it is a potentially pernicious alien invasive plant. Although the current distribution of S. reflexa is restricted to Liaoning province and thus far has limited impact on local environments, local regulatory authorities should pay close attention to this plant and take measures to stop its expansion. This is the first time that an invasive plant from the Lamiaceae (mint family) has been documented from cold environments in China.  相似文献   

The complete genome of the antifungal bacterium Pseudomonas sp. strain MS82     

Ma  Lin  Qu  Shaoxuan  Lin  Jinsheng  Jia  Jiayuan  Baird  Sonya M.  Jiang  Ning  Li  Huiping  Hou  Lijuan  Lu  Shi-En 《植物病害和植物保护杂志》2019,126(2):153-160

Journal of Plant Diseases and Protection - The genomic sequence of Pseudomonas sp. strain MS82 isolated from the rhizosphere of a soybean plant is reported and analyzed in relation to its extensive...  相似文献