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61.
Miaomiao Shen Yanshen Nie Yueyue Chen Xiufeng Zhang Jie Zhao 《International journal of molecular sciences》2021,22(1)
Meiotic recombination 11 (Mre11) is a relatively conserved nuclease in various species. Mre11 plays important roles in meiosis and DNA damage repair in yeast, humans and Arabidopsis, but little research has been done on mitotic DNA replication and repair in rice. Here, it was found that Mre11 was an extensively expressed gene among the various tissues and organs of rice, and loss-of-function of Mre11 resulted in severe defects of vegetative and reproductive growth, including dwarf plants, abnormally developed male and female gametes, and completely abortive seeds. The decreased number of cells in the apical meristem and the appearance of chromosomal fragments and bridges during the mitotic cell cycle in rice mre11 mutant roots revealed an essential role of OsMre11. Further research showed that DNA replication was suppressed, and a large number of DNA strand breaks occurred during the mitotic cell cycle of rice mre11 mutants. The expression of OsMre11 was up-regulated with the treatment of hydroxyurea and methyl methanesulfonate. Moreover, OsMre11 could form a complex with OsRad50 and OsNbs1, and they might function together in non-homologous end joining and homologous recombination repair pathways. These results indicated that OsMre11 plays vital roles in DNA replication and damage repair of the mitotic cell cycle, which ensure the development and fertility of rice by maintaining genome stability. 相似文献
62.
区块链是随比特币等数字货币兴起的一种全新的去中心化架构, 具有去信任化的特点。在区块链中用假名来提供匿名性, 然而研究表明这种匿名并不安全, 通过交易图谱分析可以发现不同假名间的关联性, 找到同一用户的假名, 破坏匿名性。通过地址的混合可以解决这一问题。本文提出了一种去中心化的混币方法, 通过分析证明, 该方法能有效地保障用户的隐私, 还能实现用户不同金额的混合, 增加便捷性。 相似文献
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65.
采用静电纺丝技术制备了热塑性聚氨酯弹性体(TPU)纳米纤维膜,并通过“Biscrolling”的方法制备高弹性过渡金属碳化物/氮化物(Ti3C2Tx MXene)改性TPU纳米纤维纱线。通过SEM、电阻测试、传感性能测试等对复合纳米纤维纱线进行结构和性能表征。结果显示,随着MXene负载量增加,复合纱线的强度先增加后降低,断裂伸长率可高达459%以上,展现出优异的弹性和弹性回复性;MXene片可在纳米纤维纱线表面及内部形成连续导电薄膜,赋予复合纱线较好的导电性(电阻76 Ω/cm)。纱线的应变传感性能测定实验表明,MXene/TPU纳米纤维纱线的传感系数可高达477.86,线性度高达0.995,高于绝大多数文献报道的纱线传感器,并且可以监测人体的各种运动状态,展现出较好的应变传感性能,在智能可穿戴领域展现出广泛的应用前景。 相似文献
66.
Pengcheng Nie Fangfang Qu Lei Lin Yong He Xuping Feng Liang Yang Huaqi Gao Lihua Zhao Lingxia Huang 《International journal of molecular sciences》2021,22(7)
Molecular spectroscopy has been widely used to identify pesticides. The main limitation of this approach is the difficulty of identifying pesticides with similar molecular structures. When these pesticide residues are in trace and mixed states in plants, it poses great challenges for practical identification. This study proposed a state-of-the-art method for the rapid identification of trace (10 mg·L−1) and multiple similar benzimidazole pesticide residues on the surface of Toona sinensis leaves, mainly including benzoyl (BNL), carbendazim (BCM), thiabendazole (TBZ), and their mixtures. The new method combines high-throughput terahertz (THz) imaging technology with a deep learning framework. To further improve the model reliability beyond the THz fingerprint peaks (BNL: 0.70, 1.07, 2.20 THz; BCM: 1.16, 1.35, 2.32 THz; TBZ: 0.92, 1.24, 1.66, 1.95, 2.58 THz), we extracted the absorption spectra in frequencies of 0.2–2.2 THz from images as the input to the deep convolution neural network (DCNN). Compared with fuzzy Sammon clustering and four back-propagation neural network (BPNN) models (TrainCGB, TrainCGF, TrainCGP, and TrainRP), DCNN achieved the highest prediction accuracies of 100%, 94.51%, 96.26%, 94.64%, 98.81%, 94.90%, 96.17%, and 96.99% for the control check group, BNL, BCM, TBZ, BNL + BCM, BNL + TBZ, BCM + TBZ, and BNL + BCM + TBZ, respectively. Taking advantage of THz imaging and DCNN, the image visualization of pesticide distribution and residue types on leaves was realized simultaneously. The results demonstrated that THz imaging and deep learning can be potentially adopted for rapid-sensing detection of trace multi-residues on leaf surfaces, which is of great significance for agriculture and food safety. 相似文献
67.
Ali Raza Wei Su Ang Gao Sundas Saher Mehmood Muhammad Azhar Hussain Wenlong Nie Yan Lv Xiling Zou Xuekun Zhang 《International journal of molecular sciences》2021,22(8)
Catalase (CAT) is an antioxidant enzyme expressed by the CAT gene family and exists in almost all aerobic organisms. Environmental stresses induce the generation of reactive oxygen species (ROS) that eventually hinder plant growth and development. The CAT enzyme translates the hydrogen peroxide (H2O2) to water (H2O) and reduce the ROS levels to shelter the cells’ death. So far, the CAT gene family has not been reported in rapeseed (Brassica napus L.). Therefore, a genome-wide comprehensive analysis was conducted to classify the CAT genes in the rapeseed genome. The current study identified 14 BnCAT genes in the rapeseed genome. Based on phylogenetic and synteny analysis, the BnCATs belong to four groups (Groups I–IV). A gene structure and conserved motif analysis showed that Group I, Group II, and Group IV possess almost the same intron/exon pattern, and an equal number of motifs, while Group III contains diverse structures and contain 15 motifs. By analyzing the cis-elements in the promoters, we identified five hormone-correlated responsive elements and four stress-related responsive elements. Further, six putative bna-miRNAs were also identified, targeting three genes (BnCAT4, BnCAT6, and BnCAT8). Gene ontology (GO) enrichment analysis showed that the BnCAT genes were largely related to cellular organelles, ROS response, stimulus response, stress response, and antioxidant enzymes. Almost 10 BnCAT genes showed higher expression levels in different tissues, i.e., root, leaf, stem, and silique. The expression analysis showed that BnCAT1–BnCAT3 and BnCAT11–BnCAT13 were significantly upregulated by cold, salinity, abscisic acid (ABA), and gibberellic acid (GA) treatment, but not by drought and methyl jasmonate (MeJA). Notably, most of the genes were upregulated by waterlogging stress, except BnCAT6, BnCAT9, and BnCAT10. Our results opened new windows for future investigations and provided insights into the CAT family genes in rapeseed. 相似文献
68.
Chen Yu Bing Zhao Yan Li Hengchang Zang Lian Li 《International journal of molecular sciences》2021,22(10)
Osteoarthritis (OA) is a degenerative disease, and there is currently no effective medicine to cure it. Early prevention and treatment can effectively reduce the pain of OA patients and save costs. Therefore, it is necessary to diagnose OA at an early stage. There are various diagnostic methods for OA, but the methods applied to early diagnosis are limited. Ordinary optical diagnosis is confined to the surface, while laboratory tests, such as rheumatoid factor inspection and physical arthritis checks, are too trivial or time-consuming. Evidently, there is an urgent need to develop a rapid nondestructive detection method for the early diagnosis of OA. Vibrational spectroscopy is a rapid and nondestructive technique that has attracted much attention. In this review, near-infrared (NIR), infrared, (IR) and Raman spectroscopy were introduced to show their potential in early OA diagnosis. The basic principles were discussed first, and then the research progress to date was discussed, as well as its limitations and the direction of development. Finally, all methods were compared, and vibrational spectroscopy was demonstrated that it could be used as a promising tool for early OA diagnosis. This review provides theoretical support for the application and development of vibrational spectroscopy technology in OA diagnosis, providing a new strategy for the nondestructive and rapid diagnosis of arthritis and promoting the development and clinical application of a component-based molecular spectrum detection technology. 相似文献
69.
利用硫磺、碳等还原硫酸法钛白粉生产副产物钛白石膏是处理钛白石膏堆放问题的方法之一。针对硫磺在回转窑分解钛白石膏制硫酸和氧化钙的过程存在时间长、硫磺用量大、硫化钙产量不高等问题,提出了以钛白石膏为原料利用酸浸法去除铁杂质后,利用硫磺为还原剂将石膏在气固竖式反应器中煅烧生成硫化钙和二氧化硫,前者再与硫酸钙煅烧制得氧化钙和二氧化硫,得到的氧化钙可以中和废酸和废水,产生的二氧化硫用来制硫酸的方法。先利用反应热力学计算软件HSC分析确定实验方案,分别在流态化实验(800 ℃,保温40 min)和煅烧实验(1 100℃,保温1.5 h)后得到硫化钙转化率与氧化钙纯度均达到90%左右。再利用Aspen软件模拟了工艺流程,模拟出二氧化硫体积分数可达12.09%,满足制硫酸的需求。硫酸生产成本估算为263.9元/t,具有较大的市场前景。 相似文献
70.
Nie Zuoren Zhang Xinming Yin Zhimin Department of Materials Science Engineering Central South University of Technology Changsha 《中国有色金属学会会刊》1997,(3)
MICROSTRUCTURESANDTEXTURESINCOLDROLLEDALUMINIUMSTRIP①NieZuoren,ZhangXinming,YinZhiminDepartmentofMaterialsScienceandEngineri... 相似文献