Content Comparison of Three Kinds of Flavonoids in Powders of Tartary Buckwheat of Different Parts

The contents of rutin,quercetin and kaempferol in powders of tartary buckwheat of different parts were determined by high-performance liquid chromatography( HPLC). The results showed that the contents of the three kinds of flavonoids differed greatly in the powders of tartary buckwheat of different parts. The contents of rutin and quercetin in the powder of tartary buckwheat sprouts were significantly higher than those in the powders of tartary buckwheat leaves and seeds. The content of kaempferol was highest in the powder of tartary buckwheat seeds. It indicates that high-performance liquid chromatography can be used for quality control of tartary buckwheat powder for its time saving,cost saving and accurate and reliable results. The content of rutin in the powder of tartary buckwheat sprouts was highest,suggesting that it is more suitable for the development of various foods based on tartary buckwheat powder.

Physiological Response to High Temperature and Evaluation of Heat Tolerance of Different Grape Cultivars

[Objectives]This study was conducted to investigate the differences in the physiological responses of different grape cultivars to high temperature.[Methods]The 19 tested cultivars were selected from the grape germplasm resources pool of Turpan Research Institute of Xinjiang Academy of Agricultural Sciences.Twelve physiological indexes including gas exchange parameters,chlorophyll content,antioxidant enzyme activity and proline content were determined in grape leaves under field conditions during the middle period of local natural high temperature period(July,daily maximum air temperature>35℃).The heat tolerance of different cultivars was evaluated by fuzzy membership function analysis and optimum partitioning clustering of ordered samples.[Results](1)Under natural high temperature conditions in Turpan,the 19 tested grape cultivars responded differently to high temperature.‘Red Globe’,‘Fujiminori’,‘Beta’,‘Hetianhuang’had strong heat tolerance,while‘Thompson Seedless’,‘Hongqi Tezaomeigui’,‘Shuijing Wuhe’,‘Victoria’,‘Yatomi Rosa’and‘Crimson Seedless’had weak heat tolerance.(2)Among the 12 physiological indexes,malondialdehyde content and antioxidant enzyme activity were mostly different among various grape cultivars.The grape cultivars with strong heat tolerance,‘Red Globe’and‘Fujiminori’,had relatively lower malondialdehyde contents,while‘Beta’and‘Hetianhuang’had relatively higher malondialdehyde contents.But they had higher activity of antioxidant enzymes.(3)The results of fuzzy membership function analysis showed that the cumulative membership value(AR)of each physiological index was consistent with its apparent heat tolerance performance,suggesting that AR can be a potential index for the evaluation of heat tolerance of grape cultivars.Further cluster analysis classified the tested cultivars as strong,medium and weak.‘Red Globe’,‘Fujiminori’,‘Beta’and‘Hetianhuang’had strong heat tolerance.[Conclusions]This study provides a reference for grape cultivation under high temperature and stress and breeding of heat-tolerant varieties.

Asymmetric Synthesis of Dihydrospirotryprostatin B via a Silica Gel-Mediated Cyclization of Tryptamine-Ynamide

Comprehensive Summary An asymmetric synthesis of dihydrospirotryprostatin B was achieved in 15 steps(8 purifications)from L-tryptophan.The main feature of our synthetic strategy is the efficient construction of spirocyclic oxindole intermediate containing a chiral quaternary carbon center,involving the silica gel-mediated cyclization of tryptamine-ynamide and oxidation under neat conditions.

雷达图像深度学习模型的可解释性研究与探索

虽然深度学习技术在雷达图像处理任务中获得了部分应用,但缺乏对黑盒模型的可解释性分析和全面的性能评估,限制了该技术在雷达图像领域中的应用性能、可信度和广泛性.本文从可解释性入手,提出了雷达图像深度学习黑盒模型分析思路,在开源MSTAR雷达图像数据集上进行实验验证.从深度学习模型的迁移机制和认知机理两个方面进行分析,得到了关于迁移学习、归因方法应用和模型鲁棒性评估方面的相关结论,填补了现有研究的空白.

稀疏阵列MIMO雷达参数估计研究进展

利用稀疏阵列多输入多输出(multi-input and multi-output,MIMO)雷达的虚拟孔径扩展特性开展参数估计研究具有重要的理论意义和应用前景.本文以稀疏阵列MIMO雷达设计和参数估计为导向,以提高估计精度和降低运算量为落脚点,从子空间类和压缩感知类算法的契合点出发,围绕阵列设计、波达方向估计、角度联合估计等方面,构建了系统的稀疏阵列MIMO雷达参数估计理论.最后,从阵列优化设计、混合目标参数估计、非理想因素抑制和分布式平台搭建等方面展望了稀疏阵列MIMO雷达的发展趋势.

Correction of β-thalassemia mutant by base editor in human embryos

β-Thalassemia is a global health issue, caused by mutations in the HBB gene. Among these mutations, HBB -28 （A〉G） mutations is one of the three most common mutations in China and Southeast Asia patients with β-thalassemia. Correcting this mutation in human embryos may prevent the disease being passed onto future generations and cure anemia. Here we report the first study using base editor （BE） system to correct disease mutant in human embryos. Firstly, we produced a 293T cell line with an exogenous HBB -28 （A〉G） mutant fragment for gRNAs and targeting efficiency evaluation. Then we collected primary skin fibroblast cells from a β-thalassemia patient with HBB -28 （A〉G） homozygous mutation. Data showed that base editor could precisely correct HBB -28 （A〉G） mutation in the patient＇s primary cells. To model homozygous mutation disease embryos, we consb＇ucted nuclear transfer embryos by fusing the lymphocyte or skin fibroblast cells with enucleated in vitro matured （IVM） oocytes.Notably, the gene correction efficiency was over 23.0% in these embryos by base editor. Although these embryos were still mosaic, the percentage of repaired blastomeres was over 20.0%. In addition, we found that base editor variants, with narrowed deamination window, could promote G-to-A conversion at HBB -28 site precisely in human embryos. Collectively, this study demonstrated the feasibility of curing genetic disease in human somatic cells and embryos by base editor system.

Au(Ⅰ)-Catalyzed 6-endo-dig Cyclizations of Aromatic 1,5-Enynes to 2-(Naphthalen-2-yl)anilines Leading to Divergent Syntheses of Benzo[α]carbazole, Benzo[c,h]cinnoline and Dibenzo[i]phenanthridine Derivatives

A gold(Ⅰ)-catalyzed 6-endo-dig cyclization of aromatic 1,5-enynes was developed to synthesize 2-(naphthalen-2-yl)anilines.The functional group tolerance of this cyclization was examined systematically and a possible mechanism was proposed.The derivatization of 2-(naphthalen-2-yl)aniline was carried out to facile access to benzo[α]carbazole,benzo[c,h]cinnoline and dibenzo[i]phenanthridine derivatives in a divergent way.

Zebrafish Cdh5 negatively regulates mobilization of aorta-gonad-mesonephros-derived hematopoietic stem cells

Establishment of a hematopoietic stem cell（HSC）pool depends on the appropriate formation,maturation and mobilization of HSCs in vertebrates.In mice,the aorta-gonad-mesonephros（AGM）is a prominent site for the formation of definitive HSCs from endothelial cells,although the placenta and yolk sac also give rise to HSCs（Mikkola and Orkin,2006;Chen et al.,2009）.After formation,AGM-derived HSCs migrate to the fetal liver（FL）,and ultimately to the bone marrow （BM）, two definitive hematopoietic organs （Cumano and Godin, 2007）.