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3-Epi-betulinic acid 3-O-β-D-glucopyranoside(eBAG)induces autophagy by activation of AMP-activated protein kinase in hepatocellular carcinoma
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作者 Mengjie liu Xuqiang liu +6 位作者 Kaiyue He Yongping Jian yujia li Jinrong Guo Jingyu Yang Zhixiang Xu Wenyi Kang 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1453-1464,共12页
3-Epi-betulinic acid 3-O-β-D-glucopyranoside(eBAG)is a pentacyclic triterpene mainly distributed in food and medicinal plants,which exhibits various pharmacological properties.However,whether these functions are attr... 3-Epi-betulinic acid 3-O-β-D-glucopyranoside(eBAG)is a pentacyclic triterpene mainly distributed in food and medicinal plants,which exhibits various pharmacological properties.However,whether these functions are attributed to eBAG or additional components in these plants remain unknown.Herein,we report that eBAG exerted an inhibitory activity against hepatocellular carcinoma and esophageal cancer cells.EBAG induced non-apoptotic cell death in hepatocellular carcinoma cells.The eBAG-induced cell death was inhibited by knock-down of autophagy related gene(ATG)5 and ATG7,by administration of 3-methyladenine,a selective autophagy inhibitor that suppresses phosphoinositide 3-kinase(PI3K),and by chloroquine,a classic autophagy flux inhibitor.We demonstrated that eBAG induced an autophagy-mediated cell death.Application of eBAG mimicked cellular bioenergetics depletion leading to the reduction of intracellular ATP,activation of AMP-activated protein kinase(AMPK),and inhibition of mTOR.Co-treatment with compound C,an AMPK inhibitor,abrogated cell death induced by eBAG.We further validated the anti-tumor effect of eBAG in the murine xenograft model of hepatocellular carcinoma and found that eBAG treatment promoted the induction of autophagy and reduction of tumor growth in mice.As a functional food ingredient,eBAG is a potential therapeutic agent for the treatment of hepatocellular carcinoma and esophageal cancer. 展开更多
关键词 eBAG AUTOPHAGY ATP AMPK Hepatocellular carcinoma
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Design and Analysis of an Active Helical Drive Downhole Tractor 被引量:2
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作者 yujia li Qingyou liU +1 位作者 Yonghua CHEN Tao REN 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第2期428-437,共10页
During oil-gas well drilling and completion,downhole tools and apparatus should be conveyed to the destination to complete a series of downhole works.Downhole tractors have been used to convey tools in complex wellbor... During oil-gas well drilling and completion,downhole tools and apparatus should be conveyed to the destination to complete a series of downhole works.Downhole tractors have been used to convey tools in complex wellbores, however a very large tractive force is needed to carry more downhole tools to accomplish works with high efficiency. A novel serial active helical drive downhole tractor which has significantly improved performance compared with previous work is proposed. All previously reported helical drive downhole tractors need stators to balance the torque generated by the rotator. By contrast, the proposed serial downhole tractor does not need a stator; several rotator-driven units should only be connected to one another to achieve a tractive force multifold higher than that was previously reported. As a result,the length of a single unit is shortened, and the motion flexibility of the downhole tractor is increased. The major performance indicators, namely, gear ratio, velocity, and tractive force, are analyzed. Experimental results show that the maximum tractive force of a single-unit prototype with a length of 900 mm is 165.3 kg or 1620 N. The analysis and experimental results show that the proposed design has considerable potential for downhole works. 展开更多
关键词 井下工具 螺旋驱动 拖拉机 设计 最大牵引力 井下工程 性能指标 运动灵活性
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Oscillation neuron based on a low-variability threshold switching device for high-performance neuromorphic computing
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作者 yujia li Jianshi Tang +5 位作者 Bin Gao Xinyi li Yue Xi Wanrong Zhang He Qian Huaqiang Wu 《Journal of Semiconductors》 EI CAS CSCD 2021年第6期64-69,共6页
Low-power and low-variability artificial neuronal devices are highly desired for high-performance neuromorphic computing.In this paper,an oscillation neuron based on a low-variability Ag nanodots(NDs)threshold switchi... Low-power and low-variability artificial neuronal devices are highly desired for high-performance neuromorphic computing.In this paper,an oscillation neuron based on a low-variability Ag nanodots(NDs)threshold switching(TS)device with low operation voltage,large on/off ratio and high uniformity is presented.Measurement results indicate that this neuron demonstrates self-oscillation behavior under applied voltages as low as 1 V.The oscillation frequency increases with the applied voltage pulse amplitude and decreases with the load resistance.It can then be used to evaluate the resistive random-access memory(RRAM)synaptic weights accurately when the oscillation neuron is connected to the output of the RRAM crossbar array for neuromorphic computing.Meanwhile,simulation results show that a large RRAM crossbar array(>128×128)can be supported by our oscillation neuron owing to the high on/off ratio(>10^(8))of Ag NDs TS device.Moreover,the high uniformity of the Ag NDs TS device helps improve the distribution of the output frequency and suppress the degradation of neural network recognition accuracy(<1%).Therefore,the developed oscillation neuron based on the Ag NDs TS device shows great potential for future neuromorphic computing applications. 展开更多
关键词 threshold switching Ag nanodots oscillation neuron neuromorphic computing
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Ultra-high spectral purity laser derived from weak external distributed perturbation
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作者 Laiyang Dang ligang Huang +7 位作者 Leilei Shi Fuhui li Guolu Yin Lei Gao Tianyi Lan yujia li lidan Jiang Tao Zhu 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第2期39-48,共10页
Ultra-high spectral purity lasers are of considerable research interests in numerous fields such as coherent optical communication,microwave photonics,distributed optical fiber sensing,gravitational wave detection,opt... Ultra-high spectral purity lasers are of considerable research interests in numerous fields such as coherent optical communication,microwave photonics,distributed optical fiber sensing,gravitational wave detection,optical clock,and so on.Herein,to deeply purify laser spectrum with compact size under normal condition,we propose a novel and practical idea to effectively suppress the spontaneous radiation of the laser cavity through weak external distributed perturbation.Subsequently,a laser configuration consisting of a main lasing cavity and an external distributed feedback cavity is proposed.The feedback signal with continuous spatio-temporal phase transition controlled by a distributed feedback structure is injected into the main cavity,which can deeply suppress the coupling rate from the spontaneous radiation to the stimulated emission and extremely purify the laser spectrum.Eventually,an ultra-narrow linewidth on-chip laser system with a side mode suppression ratio greater than 80 dB,an output linewidth of 10 Hz,and a relative intensity noise less than-150 dB/Hz is successfully obtained under normal conditions.The proposed concept in this work provides a new perspective for extreme regulation of laser parameters by using weak external distributed perturbation,which can be valid for various gain-type lasers with wide wavelength bands. 展开更多
关键词 high-coherence weak external distributed perturbation narrow linewidth LASER
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“三三制”人才培养模式下化学实验教学改革的探索与实践 被引量:10
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作者 李育佳 朱成建 张剑荣 《大学化学》 CAS 2020年第2期6-9,共4页
南京大学国家级化学实验教学示范中心基于"三三制"本科人才培养理念,对化学实验教学进行了改革,完善了"专业学术类"人才培养的实验课程,加强了"交叉复合类"实验课程建设,探索了"就业创业类"人... 南京大学国家级化学实验教学示范中心基于"三三制"本科人才培养理念,对化学实验教学进行了改革,完善了"专业学术类"人才培养的实验课程,加强了"交叉复合类"实验课程建设,探索了"就业创业类"人才培养的实验课程及平台建设,取得了显著的建设成效。 展开更多
关键词 “三三制”人才培养模式 化学实验课程 教学改革
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对外旅游经济发展与中国国家形象构建 被引量:2
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作者 金刚 李雨嘉 +1 位作者 傅嘉欣 盖可瑄 《产业经济评论》 CSSCI 2022年第3期20-35,共16页
构建积极的国家形象,是中国在新发展格局下有效参与全球治理、推动形成人类命运共同体的重要抓手。长期以来,已有研究均聚焦于研究中国对外经济与文化交流等“走出去”方式对国家形象构建的影响效应,忽视了对外旅游经济发展这一“引进... 构建积极的国家形象,是中国在新发展格局下有效参与全球治理、推动形成人类命运共同体的重要抓手。长期以来,已有研究均聚焦于研究中国对外经济与文化交流等“走出去”方式对国家形象构建的影响效应,忽视了对外旅游经济发展这一“引进来”方式可能产生的作用。对外旅游经济的发展将直接推动海外公众对中国积极国家形象元素的了解与认识,打破西方国家及其媒体对中国国家形象不实的构陷。本文收集整理了13个主要西方国家社会公众2008-2017年在主流社交媒体推特(Twitter)上关于中国美食的讨论频次,将其作为衡量中国积极国家形象构建结果的代理变量,并与各国历年来华旅游人数进行匹配。在此基础上,本文识别了中国对外旅游经济发展对中国积极国家形象构建的影响效应。研究发现,各国来华旅游人数越多,该国在推特上关于中国美食的讨论频率就越高,表明对外旅游经济发展有助于构建积极的中国国家形象。经一系列稳健性检验与内生性处理后,本文的主要结论依然成立。本文研究为破解长期以来西方掌握全球话语霸权的背景下中国积极国家形象构建的难题提供了切实可行的路径,从而有助于在新发展格局下培育中国国家软实力与国际竞争力。 展开更多
关键词 国家形象 旅游经济 中国美食 社交网络
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Cultivation and Management Technologies for New Banana Cultivar ‘Refen 1’(Musa Spp. ABB,Pisang Awak Subgroup)
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作者 Fenling TANG Yanxia li +10 位作者 Fei liN yujia li Jiashui WANG Anbang WANG Yi XU Dongmei HUANG Shun SONG Qing WEI Xiaoping ZANG Tao JING Jingyang li 《Asian Agricultural Research》 2019年第5期71-75,共5页
Banana is one of the most important crops in tropical and subtropical regions of China. Fenjiao( Musa Spp. ABB,Pisang Awak subgroup) has been grown by small scale famers because of its stable market price and better s... Banana is one of the most important crops in tropical and subtropical regions of China. Fenjiao( Musa Spp. ABB,Pisang Awak subgroup) has been grown by small scale famers because of its stable market price and better sugar-acid blend. However,the traditional Fenjiao variety is susceptible to banana Fusarium wilt,has a high plant height( over 5. 0 m),and farmers lack large-scale planting techniques.Based on the traditional Fenjiao variety,we selected‘Refen 1’variety through mutagenesis technology,which has low temperature resistance,suitable to marginal soils and relatively low plant height( 3. 2-4. 0 m). This paper mainly introduces the major techniques of propagation,cultivation,and post-harvest stages of‘Refen 1’banana,including the selection of explant materials,treatment,disinfection,initial culture,nursery hardening of in vitro-produced banana plants,and transplant of tissue culture seedlings. The major points of the cultivation technology include banana plantation selection and preparation,planting methods,irrigation and fertilizer management,pruning and retaining,and prevention and control of plant diseases and insect pests. 展开更多
关键词 'Refen 1’banana Pisang Awak(ABB) BANANA propagation Cultivation TECHNOLOGY Fruit harvest and POST-HARVEST storage TECHNOLOGY
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A New Algorithm for Black-start Zone Partitioning Based on Fuzzy Clustering Analysis
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作者 yujia li Yu Zou +1 位作者 Yupei Jia Yunxia Zheng 《Energy and Power Engineering》 2013年第4期763-768,共6页
On the process of power system black start after an accident, it can help to optimize the resources allocation and accelerate the recovery process that decomposing the power system into several independent partitions ... On the process of power system black start after an accident, it can help to optimize the resources allocation and accelerate the recovery process that decomposing the power system into several independent partitions for parallel recovery. On the basis of adequate consideration of fuzziness of black-start zone partitioning, a new algorithm based on fuzzy clustering analysis is presented. Characteristic indexes are extracted fully and accurately. The raw data matrix is made up of the electrical distance between every nodes and blackstart resources. Closure transfer method is utilized to get the dynamic clustering. The availability and feasibility of the proposed algorithm are verified on the New-England 39 bus system at last. 展开更多
关键词 Black-start ZONE Partitioning Fuzzy CLUSTERING Analysis Electrical DISTANCE CLOSURE TRANSFER Method
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Growth of ZnO self-converted 2D nanosheet zeolitic imidazolate framework membranes by an ammoniaassisted strategy 被引量:6
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作者 yujia li Lu lin +5 位作者 Min Tu Pei Nian Ashlee J. Howarth Omar K. Farha Jieshan Qiu Xiongfu Zhang 《Nano Research》 SCIE EI CAS CSCD 2018年第4期1850-1860,共11页
塑造象金属那样的水晶的多孔的材料器官的框架(MOF ) 和沸石进二维(2D ) nanosheet 形成为开发高效的分子的 sieving 膜是高度合乎需要的。然而,常规脱落免职为 nanosheet MOF 管状的膜的大规模制造复杂、挑战性。第一次,这里,我们由... 塑造象金属那样的水晶的多孔的材料器官的框架(MOF ) 和沸石进二维(2D ) nanosheet 形成为开发高效的分子的 sieving 膜是高度合乎需要的。然而,常规脱落免职为 nanosheet MOF 管状的膜的大规模制造复杂、挑战性。第一次,这里,我们由 ZnO 自我变换和氨帮助报导一种直接生长技术制作 zeolitic imidazolate 框架(ZIF ) 膜在多孔的空纤维底层上由 2D nanosheets 组成;膜对大规模工业煤气的分离过程合适。为 ZIF nanosheet 膜的建议制造过程在作为一个调节的人包含铵氢氧化物的一个 ligand 答案基于 ZnO 的预先扔的薄层的局部性的自我变换。产生 ZIF 2D nanosheet 管状的膜是高度面向的并且仅仅在厚度的 50 nm。它展出优秀分子的 sieving 性能,与为 H <sub>2</sub>/CO<sub>2</sub> 分离的高 H <sub>2</sub> 渗入和选择。这种技术为大规模分子的 sieving 应用在 MOF nanosheet 膜制造显示出大诺言。 展开更多
关键词 生长技术 ZNO 2D 框架 制造过程 分离过程 工业煤气
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Recent advances in organic-based materials for resistive memory applications 被引量:7
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作者 Yang li Qingyun Qian +7 位作者 Xiaolin Zhu yujia li Mayue Zhang Jingni li Chunlan Ma Hua li Jianmei Lu Qichun Zhang 《InfoMat》 SCIE CAS 2020年第6期995-1033,共39页
With the rapid development of data-driven human interaction,advanced datastorage technologies with lower power consumption,larger storage capacity,faster switching speed,and higher integration density have become the ... With the rapid development of data-driven human interaction,advanced datastorage technologies with lower power consumption,larger storage capacity,faster switching speed,and higher integration density have become the goals of future memory electronics.Nevertheless,the physical limitations of conventional Si-based binary storage systems lag far behind the ultrahigh-density requirements of post-Moore information storage.In this regard,the pursuit of alternatives and/or supplements to the existing storage technology has come to the forefront.Recently,organic-based resistive memory materials have emerged as promising candidates for next-generation information storage applications,which provide new possibilities of realizing high-performance organic electronics.Herein,the memory device structure,switching types,mechanisms,and recent advances in organic resistive memory materials are reviewed.In particular,their potential of fulfilling multilevel storage is summarized.Besides,the present challenges and future prospects confronted by organic resistive memory materials and devices are discussed. 展开更多
关键词 data storage MEMRISTORS organic electronics organic-inorganic hybrids resistive memory SEMICONDUCTORS
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Polarization evolution dynamics of dissipative soliton fiber lasers 被引量:1
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作者 Lei Gao Yulong Cao +7 位作者 Stefan Wabnitz Hongqing Ran lingdi Kong yujia li Wei Huang ligang Huang Danqi Feng Tao Zhu 《Photonics Research》 SCIE EI CSCD 2019年第11期1331-1339,共9页
Dissipative solitons emerge as stable pulse solutions of nonintegrable and nonconservative nonlinear physical systems, owing to a balance of nonlinearity, dispersion, and loss/gain. A considerable research effort has ... Dissipative solitons emerge as stable pulse solutions of nonintegrable and nonconservative nonlinear physical systems, owing to a balance of nonlinearity, dispersion, and loss/gain. A considerable research effort has been dedicated to characterizing amplitude and phase evolutions in the spatiotemporal dynamics of dissipative solitons emerging from fiber lasers. Yet, the picture of the buildup process of dissipative solitons in fiber lasers is incomplete in the absence of corresponding information about the polarization evolution. Here, we characterize probabilistic polarization distributions in the buildup of dissipative solitons in a net-normal dispersion fiber laser system, mode-locked by single-wall carbon nanotubes. The output optical spectra under different pump powers are filtered by a tunable filter, and are detected by a polarization state analyzer. The laser system operates from random amplified spontaneous emission into a stable dissipative soliton state as the cavity gain is progressively increased. Correspondingly, the state of polarization of each spectral wavelength converges towards a fixed point.To reveal the invariant polarization relationship among the various wavelength components of the laser output field, the phase diagram of the ellipticity angle and the spherical orientation angle is introduced. We find that,within the central spectral region of the dissipative soliton, the state of polarization evolves with frequency by tracing a uniform arc on the Poincaré sphere, whereas in the edges of the dissipative soliton spectrum, the state of polarization abruptly changes its path. Increasing cavity gain leads to spectral broadening, accompanied by a random scattering of the state of polarization of newly generated frequencies. Further increases of pump power result in dissipative soliton explosions, accompanied by the emergence of a new type of optical polarization rogue waves. These experimental results provide a deeper insight into the transient dynamics of dissipative soliton fiber lasers. 展开更多
关键词 SOLITON DISSIPATIVE dynamics
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Acousto-optic tunable ultrafast laser with vector-mode-coupling-induced polarization conversion
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作者 yujia li ligang Huang +7 位作者 Haonan Han Lei Gao Yulong Cao Yuan Gong Wending Zhang Feng Gao Iroegbu Paul Ikechukwu Tao Zhu 《Photonics Research》 SCIE EI CSCD 2019年第7期113-120,共8页
Acousto-optic interactions, employed in the ultrafast laser regulation,possess remarkable advantages for fast tuning performance in a wide spectral range. Here, we propose an ultrafast fiber laser whose wideband tunab... Acousto-optic interactions, employed in the ultrafast laser regulation,possess remarkable advantages for fast tuning performance in a wide spectral range. Here, we propose an ultrafast fiber laser whose wideband tunability is provided by an acousto-optic structure fabricated with an etched single-mode fiber. Because of the laser polarization conversion induced by the coupling between the core and cladding vector modes in the etched fiber,a band-pass characteristic of the acousto-optic interaction is achieved to effectively regulate the inner-cavity gain range. Cooperating with a saturable absorber based on single-wall carbon nanotubes (SWCNTs) with polarization robustness,a soliton operating state is achieved in the tunable erbium-doped fiber laser.By controlling the acoustical wave frequency from 1.039 to 1.069 MHz, this soliton laser can be conveniently tuned in a wide spectral range from 1571.52 to 1539.26nm.Meanwhile, the laser pulses have near-transform-limited durations stably maintaining less than 2 ps at different wavelength channels,owing to the broadband nonlinear absorption of SWCNTs. 展开更多
关键词 polarization ACOUSTO-OPTIC INTERACTIONS nonlinear
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China's Economic Growth:The“Two-Dimensional Driving Effect”of Data Factors
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作者 Yan Yang li Wang +1 位作者 yujia li Zujun liao 《China Finance and Economic Review》 2023年第4期86-107,共22页
Data factors have become one of the five essential production factors,but their role in economic growth has always been ambiguous.Starting from AI technologies,this paper establishes an endogenous growth model of data... Data factors have become one of the five essential production factors,but their role in economic growth has always been ambiguous.Starting from AI technologies,this paper establishes an endogenous growth model of data factors affecting economic growth,constructs the generation path and value path of data factors,and estimates the value of new data factors at the provincial level in China from 1999 to 2018 accordingly.Based on theoretical analyses and empirical tests,it clarifes that data factors have a“two-dimensional driving effect”on China's economic growth,that is,data factors can drive growth both directly through its own economic growth effect and indirectly by promoting technological progress.Furthermore,this paper makes three extended discussions,aiming to make a trial study on the impacts of local government big data transaction platforms on data factors and their growth effects,discuss whether it is possible to reduce the uncertainties of local economic policy based on the nature of data factors,and make a preliminary survey of the output elasticity of data factors between 1999 and 2018. 展开更多
关键词 data factors economic growth AI economic growth effect
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Macrophage Phenotypes and Hepatitis B Virus Infection 被引量:1
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作者 yujia li Shilin li +3 位作者 Xiaoqiong Duan Chunhui Yang Min Xu limin Chen 《Journal of Clinical and Translational Hepatology》 SCIE 2020年第4期424-431,共8页
Globally, hepatitis B virus (HBV) infection and its related liver diseases account for 780,000 deaths every year. Outcomes of HBV infection depend on the interaction between the virus and host immune system. It is bec... Globally, hepatitis B virus (HBV) infection and its related liver diseases account for 780,000 deaths every year. Outcomes of HBV infection depend on the interaction between the virus and host immune system. It is becoming increasingly apparent that Kupffer cells (KCs), the largest population of resident and monocyte-derived macrophages in the liver, contribute to HBV infection in various aspects. These cells play an important role not only in the anti-HBV immunity including virus recognition, cytokine production to directly inhibit viral replication and recruitment and activation of other immune cells involved in virus clearance but also in HBV outcome and progression, such as persistent infection and development of end-stage liver diseases. Since liver macrophages play multiple roles in HBV infection, they are directly targeted by HBV to benefit its life cycle. In the present review, we briefly outline the current advances of research of macrophages, especially the studies of their phenotypes, in chronic HBV infection. 展开更多
关键词 Hepatitis B virus Chronic HBV infection MACROPHAGE PHENOTYPE
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