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991.
992.
Zhong-hua SHENG Xiang-jin WEI Gao-neng SHAO Jian SONG Ju LUO Pei-song HU Shao-qing TANG Li-yun CHEN 《水稻科学》2013,20(5):336-342
A new white striped leaf mutant wsl1 was discovered from Nipponbare mutated by ethyl methanesulfonate. The mutant showed white striped leaves at the seedling stage and the leaves gradually turned green after the tillering stage. The chlorophyll content of wsl1 was significantly lower than that of wild-type during the fourth leaf stage, tillering stage and booting stage. The numbers of chloroplast, grana and grana lamella were reduced and the thylakoids were degenerated in wsl1 compared with wild type. Genetic analysis showed that the wsl1 was controlled by a single recessive gene. Molecular mapping of the wsl1 was performed using an F2 population derived from wsl1/Nanjing 11. The wsl1 was finally mapped on the telomere region of chromosome 9 and positioned between simple sequence repeat markers RM23742 and RM23759 which are separated by approximately 486.5 kb. The results may facilitate map-based cloning of wsl1 and understanding of the molecular mechanism of the regulation of leaf-color by WSL1 in rice. 相似文献
993.
利用固相微萃取法(SPME)和气质联用(GC-MS)技术对中国产黑珍珠莲雾Syzyzgium samarangense果实5个不同发育阶段的挥发物进行分析.共检测出44种物质,主要包括萜烯类、醇类、酮类和酯类,其中仅有8种物质是各阶段所共有的,它们是(-)-α-烯、β-石竹烯、á-芹子烯、à-芹子烯、α-依兰油烯、δ-杜松烯、2,4’,5-三甲基二苯基甲烷、邻苯二甲酸二异丁酯.酮类主要包括莰酮和反式-β-紫罗酮-5,6-环氧化物,酯类化合物包括邻苯二甲酸二异丁酯和乙酸异丁酯.在果实的不同发育阶段,挥发物成分与含量差异很大,萜烯类的相对含量随着果实的成熟而减少,莰酮和邻苯二甲酸二异丁酯的含量随着果实的成熟逐渐升高,反式-β-紫罗酮-5,6-环氧化物与乙酸异丁酯仅在成熟期才大量出现. 相似文献
994.
Xuhong Zhou Min Gui Dandan Zhao Min Chen Suping Ju Shenchong Li Zhenhong Lu Xijun Mo Jihua Wang 《Euphytica》2013,189(3):471-483
Reproductive barriers often exist in 4x–2x crosses in Dianthus caryophyllus L. and seriously lead to low seed set and breeding efficiency. In this study, we inspected pre-fertilization and post-fertilization barriers in crosses between ‘butterfly’ (2n = 4x = 60) and the fertile breeding line ‘NH10’ (2n = 2x = 30) and ‘NH14’ (2n = 2x = 30) using fluorescence microscopy and paraffin section. The growth of the pollen tubes up to the ovary was observed in crosses of ‘butterfly’ × ‘NH10’ and ‘butterfly’ × ‘NH14’. However, abnormalities of pollen tube including coiled and spiky and callose deposition in incompatible tubes has also been detected. In the cross ‘butterfly’ and ‘NH10’, the number of pollen tubes at the base of the style reached the highest value, 67.2 ± 10.8 at 48 h after pollination, but the number of ovules with micropylar penetration was low, 19 ± 4.5. Similarly, in the cross between ‘butterfly’ and ‘NH14’, pollen tubes at the base of the style at 48 h after pollination was 51 ± 6.2 and the ovules with penetrated micropyles per ovary at 48 h after pollination was 11 ± 2.4. It indicated the pollen tubes difficultly penetrated into the ovules in 4x–2x crosses. In addition, it was observed that non-fused of egg and sperm or non-fused polar nucleus resulted in endosperm without embryos, and embryos without endosperm. Embryos aborted at different developmental stages (prembryo to cotyledon embryo, main globular embryo), which might be related to a deficient endosperm development in reciprocal crosses. The results suggested that pre-fertilization and post-fertilization barriers were detected in these combinations. Due to the post-fertilization barriers in 4x–2x crosses, the embryo rescue might be contributed to obtain hybrid F1 plants. 相似文献
995.
The Kalman filtering algorithm and commonly used maneuvering target tracking models in the target tracking are firstly studied in this paper, tracking performances of all models based on the Kalman filtering algorithm are simulated and analyzed. Then, multiple model target tracking algorithm is analyzed and studied, which uses multiple motion models to match different target motion models and exists interacting between all models. In this paper,the target tracking of shipboard radar is simulated with MATLAB. It shows the feasibility of the interacting multiple model algorithm composed of a CV model and a CA model. The simulation results indicate,this algorithm obtains a better performance in tracking high speed and high maneuvering targets and a better balance between the performance and computational complexity,as well as very practicability, which is suitable for the tracking target of shipboard radar tracking target. 相似文献
996.
Study on separation algorithm of convolutive mixing model and separation of mixing signals of multiple partial discharges
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To identify individual partial discharges(PD)signals produced by multiple insulation defects in gas insolated switchgear (GIS),this paper analyses the mechanism of propagation and mixing of multiple PD electromagnetic wave signals in GIS cylinder and proposes the convolutive mixing model to describe it for a separation algorithm to acquire individual PD signals. With the non-stationary property,mixing PD signals are changed at time domain into a set consisting of short-time stationary PD signals and then the Molgedey-Schuster decorrelation approach is employed to separate these stationary PD signals at frequency domain. The correlation of the envelope of separated PD signals in this set is used to reconstruct PD signals to realize the separation of non-stationary UHF PD mixtures. The effective separation of actual UHF PD mixing signals validates the assumption of convolutive mixing process in GIS and also offers a new approach to the identification of mixing PD signals by external ultra-high frequency detection scheme from multiple insulation defects in GIS. 相似文献
997.
Panpan Cui Benazir Abbasi Defeng Lin Rong Rui Shiqiang Ju 《Reproduction in domestic animals》2020,55(5):584-593
As common overexpression of Aurora A in various tumours, much attention has focused on its function in inducing cancer, and its value in cancer therapeutics, considerably less is known regarding its role in the first cleavage division of mammalian embryos. Here, we highlight an indispensable role of Aurora A during the first mitotic division progression of pig embryos just after meiosis. The expression and spatiotemporal localization of Aurora A were initially assessed in pig embryos during the first mitotic division by Western blot analysis and indirect immunofluorescent staining. Then, the potential role of Aurora A was further evaluated using a highly selective Aurora A inhibitor, MLN8054, during this mitotic progression in pig embryos. Aurora A was found to express and exhibit a specific dynamic intracellular localization pattern during the first mitotic division in pig embryos. Aurora A was diffused in the cytoplasm at the prophase stage, and then exhibited a dynamic intracellular localization which was tightly associated with the chromosome and spindle dynamics throughout subsequent mitotic phases. Inhibition of Aurora A by MLN8054 treatment led to the failure of the first cleavage, with the majority of embryos being arrested in prophase of the mitotic division. Further subcellular structure examination showed that Aurora A inhibition not only led to the failure of spindle microtubule assembly, but also resulted in severe defects in chromosome condensation, accompanied by an obvious decrease in p-TACC3(S558) expression during the prophase of the first mitosis. Together, these results illustrated that Aurora A is crucial for both spindle assembly and chromosome condensation during the first mitotic division in pig embryos, and that the regulation of Aurora A may be associated with its effects on p-TACC3(S558) expression. 相似文献
999.
1000.
正教师是决定高校人才培养质量和学校发展水平的第一要素,是学院教学、科研、社会服务等活动的实施主体,教师评价是高校师资队伍建设的核心措施。2016年8月25日,教育部印发《关于深化高校教师考核评价制度改革的指导意见》,明确指出完善教师考核评价制度是目前及今后一段时期深化高等教育综合改革的紧迫任务。当前,新一轮高职教育改革发展已经步入一个新的阶段。建设一批高水平高职院校和高水平高职专业,不仅能发挥典型和榜样的作用,还有利于对全国1 300多所高职院校的发展产生引领作用和深远影响。 相似文献