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31.
Liuping Chen Qian Lv Weibing Yang Hui Yang Qiaoyan Chen Bingxin Wang Yanhong Lei Yanzhou Xie 《International journal of molecular sciences》2022,23(9)
Drought stress is an important factor that severely affects crop yield and quality. Autophagy has a crucial role in the responses to abiotic stresses. In this study, we explore TaNBR1 in response to drought stress. Expression of the TaNBR1 gene was strongly induced by NaCl, PEG, and abscisic acid treatments. The TaNBR1 protein is localized in the Golgi apparatus and autophagosome. Transgenic Arabidopsis plants overexpressing TaNBR1 exhibited reduced drought tolerance. When subjected to drought stress, compared to the wild-type (WT) lines, the transgenic overexpressing TaNBR1 plants had a lower seed germination rate, relative water content, proline content, and reduced accumulation of antioxidant enzymes, i.e., superoxide dismutase, peroxidase, and catalase, as well as higher chlorophyll losses, malondialdehyde contents, and water loss. The transgenic plants overexpressing TaNBR1 produced much shorter roots in response to mannitol stress, in comparison to the WT plants, and they exhibited greater sensitivity to abscisic acid treatment. The expression levels of the genes related to stress in the transgenic plants were affected in response to drought stress. Our results indicate that TaNBR1 negatively regulates drought stress responses by affecting the expression of stress-related genes in Arabidopsis. 相似文献
32.
在行人重识别任务中存在数据集标注难度大,样本量少,特征提取后细节特征缺失等问题。针对以上问题提出深度双重注意力的生成与判别联合学习的行人重识别。首先,构建联合学习框架,将判别模块嵌入生成模块,实现图像生成和判别端到端的训练,及时将生成图像反馈给判别模块,同时优化生成模块与判别模块。其次,通过相邻的通道注意力模块间连接和相邻空间注意力模块间连接,融合所有通道特征和空间特征,构建深度双重注意力模块,将其嵌入教师模型,使模型能更好地提取行人细节身份特征,提高模型识别能力。实验结果表明,该算法在Market-1501和DukeMTMC-ReID数据集上具有较好的鲁棒性、判别性。 相似文献
33.
Chunxia Qiao Ming Lv Xinying Li Xiaoling Lang Shouqin Lv Mian Long Yan Li Shusheng Geng Zhou Lin Beifen Shen Jiannan Feng 《工程(英文)》2021,7(11):1566-1576
Fully human antibodies have minimal immunogenicity and safety profiles. At present, most potential antibody drugs in clinical trials are humanized or fully human. Human antibodies are mostly generated using the phage display method (in vitro) or by transgenic mice (in vivo); other methods include B lymphocyte immortalization, human–human hybridoma, and single-cell polymerase chain reaction. Here, we describe a structure-based computer-aided de novo design technology for human antibody generation. Based on the complex structure of human epidermal growth factor receptor 2 (HER2)/Herceptin, we first designed six short peptides targeting the potential epitope of HER2 recognized by Herceptin. Next, these peptides were set as complementarity determining regions in a suitable immunoglobulin frame, giving birth to a novel anti-HER2 antibody named “HF,” which possessed higher affinity and more effective anti-tumor activity than Herceptin. Our work offers a useful tool for the quick design and selection of novel human antibodies for basic mechanical research as well as for imaging and clinical applications in immune-related diseases, such as cancer and infectious diseases. 相似文献
34.
针对深部开采煤层普遍存在的构造应力复杂、透气性系数低、抽采效果差等问题,为探究最优的瓦斯抽采技术方案,以水溪煤矿K1松软煤层为研究对象,分别采用水力压裂、水力冲孔、普通抽采和高压水力压裂—冲孔联合增透4种技术,进行现场对比应用试验。结果表明:高压水力压裂—冲孔联合增透技术对煤层透气性系数的提高程度分别为水力压裂、水力冲孔和普通抽采方案的1.85、1.61、6.30倍,抽采瓦斯纯流量分别提高了1.42、1.33、2.32倍,此外,抽采汇总瓦斯浓度(CH4体积分数)保持在42.6%以上,抽采效率为四者之中最高。现场应用结果表明,高压水力压裂—冲孔联合增透技术具有明显的技术优势。 相似文献
35.
吕伟其 《Canadian Metallurgical Quarterly》2011,11(1)
根据危险化学品易燃、易爆、有毒的特点,提出安全储存和管理的管理思路,同时探讨了装卸入库的安全注意管理点. 相似文献
36.
SiO2 hollow spheres with movable Fe3O4 core were obtained by exposing the pre-synthesized Fe3O4SiO2 particles (with an adsorption interlayer of ethylene glycol) under the irradiation of electron beam inside transmission electron micrograph (TEM). In the formation process, the evaporation of adsorbed ethylene glycol and the evolution of amorphous SiO2 layer played important roles, and that should be attributed to the high temperature and trapped charges induced by the irradiation of electron beam. This work provided a new route to obtain particles with movable core structure and extended the applications of electron beam. 相似文献
37.
Liqin Yang Xinsheng Yang Li Lv Cuihua Cheng Yong Zhao 《Journal of Superconductivity and Novel Magnetism》2011,24(6):1847-1851
A novel boned perovskite manganese oxide magnetoresistant material was prepared using La0.7Sr0.3MnO3 (LSMO) as the precursor powders and metal tin (Sn) as the binder. The microstructure and phase characteristics, low-field transport properties were studied. Sn segregated at the grain boundaries of LSMO grains. The insulator–metal (I–M) transition and enhanced LFMR are only observed with a low content of Sn, due to grain boundary disorder and spin polarized tunneling between grain boundaries. The Sn addition induced resistivity decreasing dramatically. In the high temperature PM region, the resistivities for samples with low Sn content follow the adiabatic small-polaron-hopping model. 相似文献
38.
制导化改造是提高火箭弹精度最有效的一种方法.弹道仿真在制导火箭弹研究设计中占有非常重要的地位,仿真结果的正确性与合理性直接影响了制导控制系统的设计开发.为了对制导火箭弹的弹道进行仿真,首先建立了制导火箭弹的运动数学模型,而后结合风洞试验得到的动力系数进行了无控弹道仿真,得到了弹道、速度、弹道倾角和攻角等变化曲线.仿真结... 相似文献
39.
基于STC12C系列单片机的DS18B20编程 总被引:3,自引:1,他引:3
针对新一代高性能单时钟/机器周期的STC12C系列单片机由于执行速度远高于传统的51单片机而不能直接使用原有单片机程序的问题,采用Keil软件的性能分析器来计算Atmel单片机的执行时间;通过手工计算修改程序段的执行时间,使STC12C系列单片机的执行时间满足数字温度传感器DS18B20的时序要求。测试结果表明STC12C2052能正确读取DS18B20的温度转换值,此方法对于具有时序要求的可编程器件的使用具有一定的参考价值。 相似文献
40.