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31.
Lotus (Nelumbo nucifera), under the Nelumbonaceae family, is one of the relict plants possessing important scientific research and economic values. Because of this, much attention has been paid to this species on both its biology and breeding among the scientific community. In the last decade, the genome of lotus has been sequenced, and several high-quality genome assemblies are available, which have significantly facilitated functional genomics studies in lotus. Meanwhile, re-sequencing of the natural and genetic populations along with different levels of omics studies have not only helped to classify the germplasm resources but also to identify the domestication of selected regions and genes controlling different horticultural traits. This review summarizes the latest progress of all these studies on lotus and discusses their potential application in lotus breeding.  相似文献   
32.
在差别矩阵的基础上,针对不完备决策表提出了基于差别矩阵的区分对象对集定义,并证明求不完备决策表的核可以转化到求基于差别矩阵的区分对象对集上。在此基础上,提出了一种基于区分对象对的不完备决策表求核算法,该算法的时间复杂度为:[max{O(|C||U||Upos|),O(K|C||U|)}],优于同类算法的时间复杂度;用实例说明了新算法的有效性。  相似文献   
33.
在精细积分算法体系的基础上开发的"精细积分(最优)控制系统设计程序包PIM-CSD(Precise Integration Method-Control System Design)",不但具有高效、精确、稳定的优点,可替代Matlab控制工具箱定常控制器设计功能,而且很容易实现时变控制器功能的扩展.主要讲述精细积分程序包在LQ最优控制、Kalman滤波以及系统仿真等控制系统设计基本内容方面的功能实现,特别强调在时变控制器和滤波器的设计以及Kalman滤波微分方程的高效求解等新功能的扩展,通过与Matlab控制系统工具箱中相关功能的比较,显示出PIM-CSD在计算效率、数值精度、算法稳定性等方面的优势.最后,探讨了PIM-CSD的应用领域和发展方向.  相似文献   
34.
介绍了一种基于单片机的切纸机位移测量系统。该系统以AT89C2051单片机为核心,实现了对切纸机刀具位置、进刀量以及进刀次数的实时测量,完成了多位测量结果的快速显示和测量结果的掉电保护。该系统测量准确、使用方便,大大提高了切纸机位移测量的精确度和工人的工作效率。  相似文献   
35.
The path of crack propagation in a graphene sheet is significant for graphene patterning via the tearing approach. In this study, we evaluate the fracture properties of pre-cracked graphene during the tearing process, with consideration of the effects of the aspect ratio, loading speed, loading direction, and ambient temperatures on the crack propagation in the monolayer sheet. Some remarkable conclusions are drawn based on the molecular dynamic simulation results, i.e., a higher loading speed may result in a complicated path of crack propagation, and the propagation of an armchair crack may be accompanied by sp carbon links at high temperatures. The reason for this is that the stronger thermal vibration reduces the load stress difference near the crack tip and, therefore, the crack tip can pass through the sp link. A crack propagates more easily along the zigzag direction than along the armchair direction. The out-of-plane tearing is more suitable than the in-plane tearing for graphene patterning. The path of crack propagation can be adjusted by changing the loading direction, e.g., a rectangular graphene ribbon can be produced by oblique tearing. This new understanding will benefit the application of graphene patterning via the tearing approach.  相似文献   
36.
Rapid global population growth has caused an increasing need for products containing protein.Meat products are the most common high-protein food source,but impa...  相似文献   
37.
Two new different metal-organic frameworks (MOFs)[Ba(L1)(H2O)2]n·nH2O (MOF 1) and[Ba(L2)(-H2O)2]n·0.5nDMF·0.5nH2O (MOF 2) were yielded by the assembly of oxygen...  相似文献   
38.
Excessive input of nitrogen fertilizer not only causes a great waste of resources but brings about a series of ecological and environmental problems. Although Small Auxin Up-regulated RNAs (SAURs) participate in diverse biological processes, the function of SAURs in the nitrogen starvation response has not been well-studied. Here, we identified 308 TaSAURs in wheat and divided them into 10 subfamilies. The promoter regions of most TaSAURs contain hormone responsive elements, and their expression levels change under the treatment of different hormones, such as IAA, MeJA, and ABA. Interestingly, overexpression of one of the TaSAUR family members, a nitrogen starvation responsive gene, TaSAUR66-5B, can promote the growth of Arabidopsis and wheat roots. In addition, overexpression of TaSAUR66-5B in Arabidopsis up-regulates the expression levels of auxin biosynthesis related genes, suggesting that overexpression TaSAUR66-5B may promote root growth by increasing the biosynthesis of auxin. Furthermore, overexpression of TaSAUR66-5B in wheat can increase the biomass and grain yields of transgenic plants, as well as the nitrogen concentration and accumulation of both shoots and grains, especially under low nitrogen conditions. This study provides important genomic information of the TaSAUR gene family and lays a foundation for elucidating the functions of TaSAURs in improving nitrogen utilization efficiency in wheat.  相似文献   
39.
Jasmonic acid (JA) is an important hormone that functions in plant defense. cam1 and wrky53 mutants were more resistant to Spodoptera littoralis than in the wild-type (WT) Arabidopsis group. In addition, JA concentration in cam1 and wrky53 mutants was higher compared with the WT group. To explore how these two proteins affect the resistance of Arabidopsis plants, we used a yeast two-hybrid assay, firefly luciferase complementation imaging assay and in vitro pull-down assay confirming that calmodulin 1 (CAM1) interacted with WRKY53. However, these two proteins separate when calcium concentration increases in Arabidopsis leaf cells. Then, electrophoretic mobility shift assay and luciferase activation assay were used to verify that WRKY53 could bind to lipoxygenases 3 (LOX3) and lipoxygenases 4 (LOX4) gene promoters and negatively regulate gene expression. This study reveals that CAM1 and WRKY53 negatively regulate plant resistance to herbivory by regulating the JA biosynthesis pathway via the dissociation of CAM1-WRKY53, then the released WRKY53 binds to the LOXs promoters to negatively regulate LOXs gene expression. This study reveals WRKY53′s mechanism in insect resistance, a new light on the function of WRKY53.  相似文献   
40.
一种用于核辐射监测信号的多微处理系统   总被引:1,自引:0,他引:1  
介绍了4兆伏静电正离子加速器的监测防护系统,该系统由多个微处理器与主控机分布式分布,组成高速多通道辐射信号采集控制系统,可以对多点核辐射的能量、强度、剂量率,剂量及剂量当量进行监测.系统的核电路部分采用最新的芯片产品,合理的硬件安排,优化的软件编程,在仅更换不同的探头后,便可探测分析γ,X及快中子辐射.在参数稍做调整之后,就可以广泛应用于类似条件的其他场所的辐射监测.  相似文献   
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