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61.
62.
Jiaxin Liu Xiyuan Tang Linxiao Shen Shaolan Li Zhelu Li Wenjuan Guo Nan Sun 《半导体学报》2020,41(11):111403-111403-10
The successive approximation register (SAR) is one of the most energy-efficient analog-to-digital converter (ADC) architecture for medium-resolution applications. However, its high energy efficiency quickly diminishes when the target resolution increases. This is because a SAR ADC suffers from several major error source, including the sampling kT/C noise, the comparator noise, and the DAC mismatch. These errors are increasing hard to address in high-resolution SAR ADCs. This paper reviews recent advances on error suppression techniques for SAR ADCs, including the sampling kT/C noise reduction, the noise-shaping (NS) SAR, and the mismatch error shaping (MES). These techniques aim to boost the resolution of SAR ADCs while maintaining their superior energy efficiency. 相似文献
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64.
合理的景观设计抵制城市死角达到犯罪预防——以上海市徐家汇某高架公园环境分析为例 总被引:1,自引:0,他引:1
城市化进程不仅改变了传统土地组织结构与社会文化,也导致了日益严重的都市犯罪问题.特别是有些大城市随着城市发展出现了“城市死角”。该文主要探讨以合理的设计手法来倡导符合具体都市功能的环境设计,达到预防犯罪的目的,抵制城市死角。研究选取上海市典型的高架桥底舟固为模型,找出较为合理的设计通用手法来处理高架公园问题,旨在尽可能地使用城市集约空间,消除城市“死角”现象, 相似文献
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66.
Keng-Liang Ou Chiung-Fang Huang Wen-Chien Lan Bai-Hung Huang Hsu-An Pan Yung-Kang Shen Takashi Saito Hsin-Yu Tsai Yung-Chieh Cho Kuo-Sheng Hung Hsin-Hua Chou 《International journal of molecular sciences》2022,23(3)
The ability of Pluronic F127 (PF127) conjugated with tetrapeptide Gly-Arg-Gly-Asp (GRGD) as a sequence of Arg-Gly-Asp (RGD) peptide to form the investigated potential hydrogel (hereafter referred to as 3DG bioformer (3BE)) to produce spheroid, biocompatibility, and cell invasion ability, was assessed in this study. The fibroblast cell line (NIH 3T3), osteoblast cell line (MG-63), and human breast cancer cell line (MCF-7) were cultured in the 3BE hydrogel and commercial product (Matrigel) for comparison. The morphology of spheroid formation was evaluated via optical microscopy. The cell viability was observed through cell counting Kit-8 assay, and cell invasion was investigated via Boyden chamber assay. Analytical results indicated that 3BE exhibited lower spheroid formation than Matrigel. However, the 3BE appeared biocompatible to NIH 3T3, MG-63, and MCF-7 cells. Moreover, cell invasion ability and cell survival rate after invasion through the 3BE was displayed to be comparable to Matrigel. Thus, these findings demonstrate that the 3BE hydrogel has a great potential as an alternative to a three-dimensional cell culture for drug screening applications. 相似文献
67.
Peiwen Zhang Yuxu He Shuang Wu Xinrong Li Xutao Lin Mailin Gan Lei Chen Ye Zhao Lili Niu Shunhua Zhang Xuewei Li Li Zhu Linyuan Shen 《International journal of molecular sciences》2022,23(14)
Mammalian adipose tissue can be divided into white and brown adipose tissue based on its colour, location, and cellular structure. Certain conditions, such as sympathetic nerve excitement, can induce the white adipose adipocytes into a new type of adipocytes, known as beige adipocytes. The process, leading to the conversion of white adipocytes into beige adipocytes, is called white fat browning. The dynamic balance between white and beige adipocytes is closely related to the body’s metabolic homeostasis. Studying the signal transduction pathways of the white fat browning might provide novel ideas for the treatment of obesity and alleviation of obesity-related glucose and lipid metabolism disorders. This article aimed to provide an overview of recent advances in understanding white fat browning and the role of BAT in lipid metabolism. 相似文献
68.
Weiti Cui Zihan Zhuang Peihao Jiang Jincheng Pan Gan Zhao Sheng Xu Wenbiao Shen 《International journal of molecular sciences》2022,23(14)
Cinnamoyl-CoA reductase (CCR) is a pivotal enzyme in plant lignin synthesis, which has a role in plant secondary cell wall development and environmental stress defense. Alfalfa is a predominant legume forage with excellent quality, but the lignin content negatively affects fodder digestibility. Currently, there is limited information on CCR characteristics, gene expression, and its role in lignin metabolism in alfalfa. In this study, we identified 30 members in the CCR gene family of Medicago sativa. In addition, gene structure, conserved motif, and evolution analysis suggested MsCCR1–7 presumably functioned as CCR, while the 23 MsCCR-likes fell into three categories. The expression patterns of MsCCRs/MsCCR-likes suggested their role in plant development, response to environmental stresses, and phytohormone treatment. These results were consistent with the cis-elements in their promoters. Histochemical staining showed that lignin accumulation gradually deepened with the development, which was consistent with gene expression results. Furthermore, recombinant MsCCR1 and MsCCR-like1 were purified and the kinetic parameters were tested under four substrates. In addition, three-dimensional structure models of MsCCR1 and MsCCR-like1 proteins showed the difference in the substrate-binding motif H212(X)2K215R263. These results will be useful for further application for legume forage quality modification and biofuels industry engineering in the future. 相似文献
69.
Yijie Shen Isaac Nape Xilin Yang Xing Fu Mali Gong Darryl Naidoo Andrew Forbes 《光:科学与应用(英文版)》2021,10(5):796-805
Vector beams, non-separable in spatial mode and polarisation, have emerged as enabling tools in many diverse applications, from communication to imaging. This a... 相似文献
70.
Li Guo Lin Jia Lulu Luo Xinru Xu Yangyang Xiang Yujie Ren Dekang Ren Lulu Shen Tingming Liang 《International journal of molecular sciences》2022,23(13)
Circular RNAs (circRNAs), a class of new endogenous non-coding RNAs (ncRNAs), are closely related to the carcinogenic process and play a critical role in tumor metastasis. CircRNAs can lay the foundation for tumor metastasis via promoting tumor angiogenesis, make tumor cells gain the ability of migration and invasion by regulating epithelial-mesenchymal transition (EMT), interact with immune cells, cytokines, chemokines, and other non-cellular components in the tumor microenvironment, damage the normal immune function or escape the immunosuppressive network, and further promote cell survival and metastasis. Herein, based on the characteristics and biological functions of circRNA, we elaborated on the effect of circRNA via circRNA-associated competing endogenous RNA (ceRNA) network by acting as miRNA/isomiR sponges on tumor angiogenesis, cancer cell migration and invasion, and interaction with the tumor microenvironment (TME), then explored the potential interactions across different RNAs, and finally discussed the potential clinical value and application as a promising biomarker. These results provide a theoretical basis for the further application of metastasis-related circRNAs in cancer treatment. In summary, we briefly summarize the diverse roles of a circRNA-associated ceRNA network in cancer metastasis and the potential clinical application, especially the interaction of circRNA and miRNA/isomiR, which may complicate the RNA regulatory network and which will contribute to a novel insight into circRNA in the future. 相似文献