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Puerariae Radix protects against ulcerative colitis in mice by inhibiting NLRP3 inflammasome activation
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作者 Yu Ga yuanyuan wei +9 位作者 Qingyu Zhao Yimeng Fan Yannan Zhang Zhifang Zhang Sijia Hao Lixia Wang Zhifen Wang Jinlong Han Shuang Wu Zhihui Hao 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2266-2276,共11页
Ulcerative colitis(UC)is a common inflammatory disease of the gastrointestinal tract.Traditional Chinese medicine(TCM)has long been used in Asia as a treatment for UC and Puerariae Radix(PR)is a reliable anti-diarrhea... Ulcerative colitis(UC)is a common inflammatory disease of the gastrointestinal tract.Traditional Chinese medicine(TCM)has long been used in Asia as a treatment for UC and Puerariae Radix(PR)is a reliable anti-diarrheal therapy.The aims of this study were to investigate the protective effect of PR using the dextran sulfate sodium salt(DSS)-induced UC model in mice and identify molecular mechanisms of PR action.The chemical constituents of PR via ultra-performance liquid chromatography/tandem mass spectrometry and identified potential PR and UC targets using a network pharmacology(NP)approach were obtained to guide mouse experiments.A total of 180 peaks were identified from PR including 48 flavonoids,46 organic acids,14 amino acids,8 phenols,8 carbohydrates,7 alkaloids,6 coumarins and 43 other constituents.NP results showed that caspase-1 was the most dysregulated of the core genes associated with UC.A PR dose of 0.136 mg/g administered to DSS treated mice reversed weight loss and decreased colon lengths found in UC mice.PR also alleviated intestinal mucosal shedding,inflammatory cell infiltration and mucin loss.PR treatment suppressed upregulation of NOD-like receptor protein 3(NLRP3),cysteinyl aspartate-specific proteases-1(caspase-1),apoptosis-associated speck-like(ASC)and gasdermin D(GSDMD)at both the protein and m RNA expression levels.The addition of a small molecule dual-specificity phosphatase inhibitor NSC 95397 inhibited the positive effects of PR.These results indicated that PR exerts a protective effect on DSS-induced colitis by inhibiting NLRP3 inflammasome activation in mice. 展开更多
关键词 Puerariae Radix Ulcerative colitis Molecular mechanisms PYROPTOSIS NOD-like receptor protein 3 inflammasome
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Mori fructus aqueous extracts attenuates liver injury by inhibiting ferroptosis via the Nrf2 pathway 被引量:1
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作者 yuanyuan wei Chen Gao +5 位作者 Huiru Wang Yannan Zhang Jinhua Gu Xiuying Zhang Xuhao Gong Zhihui Hao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第4期1418-1437,共20页
Background Liver fibrosis and hepatocellular carcinogenesis secondary to liver fibrosis are serious liver diseases with no effective treatments.Mori fructus aqueous extracts(MFAEs)have served as successful treatments ... Background Liver fibrosis and hepatocellular carcinogenesis secondary to liver fibrosis are serious liver diseases with no effective treatments.Mori fructus aqueous extracts(MFAEs)have served as successful treatments for many types of liver injury including fibrosis although the molecular mechanisms are unknown at present.Purpose To investigate the effect of MFAEs in alleviating acute and chronic liver injury and tried to decipher the underlying mechanism.Methods and results Mice were divided into 5 groups(n ps:contro=8)for acute(groups:control,0.3%CCl_(4),bifendate(BD),100 and 200 mg/kg MFAEs,7 d)and chronic(groul,10%CCl_(4),BD,100 and 200 mg/kg MFAEs,4 weeks)liver injury study.Each mouse was injected intraperitoneally with 10μL/g corn oil containing CCl_(4)expect the control group.HepG2 cells were used in vitro study.Eighteen communal components were identified by UPLC-LTQOrbitrap-MS.We utilized a mouse model for acute and chronic liver injury using CCl_(4)and MFAEs administration effectively blocked fibrosis and significantly inhibited inflammation in the liver.MFAEs activated the nuclear factor erythroid derived 2 like 2/heme oxygenase 1(Nrf2/HO-1)pathway and promoted the synthesis of the antioxidants glutathione(GSH),superoxidedismutase(SOD)and glutathione peroxidase(GSH-Px)that resulted in reduced levels of CCl_(4)-induced oxidative stress molecules including reactive oxygen species.These extracts administered to mice also inhibited ferroptosis in the liver by regulating the expression of Acyl-CoA synthetase long chain family member 4(ACSL4),solute carrier family 7 member 11(SLC7A11)and glutathione peroxidase 4(GPX4),thus reducing the occurrence of liver fibrosis.Both in vivo and in vitro tests indicated that the mechanism of MFAEs protection against liver fibrosis was linked to activation of Nrf2 signaling.These effects were blocked in vitro by the addition of a specific Nrf2 inhibitor.Conclusion MFAEs inhibited oxidative stress,ferroptosis and inflammation of the liver by activating Nrf2 signal pathway and provided a significant protective effect against CCl_(4)-induced liver fibrosis. 展开更多
关键词 Acute and chronic liver injury Ferroptosis Mori fructus aqueous extracts NRF2 Oxidative stress
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肺结节患者焦虑抑郁与Th17/Treg和炎症水平改变的相关性研究 被引量:27
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作者 王丽娜 韦媛媛 +3 位作者 胡华青 张晓雨 郑美娟 费广鹤 《中国肺癌杂志》 CAS CSCD 北大核心 2020年第7期554-560,共7页
背景与目的肺癌的发病率逐年攀升,人们在体检时尤其注重对肺进行检查,得益于低剂量计算机断层扫描技术的普及,不仅肺癌能够得到早期诊断,很多肺结节也在体检时被发现,并成为当下不可忽视的重要健康问题。肺结节患者极易出现焦虑、抑郁... 背景与目的肺癌的发病率逐年攀升,人们在体检时尤其注重对肺进行检查,得益于低剂量计算机断层扫描技术的普及,不仅肺癌能够得到早期诊断,很多肺结节也在体检时被发现,并成为当下不可忽视的重要健康问题。肺结节患者极易出现焦虑、抑郁等不良情绪,研究表明情绪障碍患者存在机体免疫功能失调和炎症水平变化,本研究旨在探讨肺结节患者焦虑抑郁与Th17/Treg和炎症水平改变的相关性。方法纳入2019年4月-2019年7月就诊于安徽医科大学第一附属医院门诊受试者共143例,采用贝克焦虑量表(Beck Anxiety Inventory,BAI)、贝克抑郁量表第二版(Beck Depression Inventory-Ⅱ,BDI-Ⅱ)进行评估。其中健康对照(healthy control,HC)组40例;肺结节患者103例,依据量表评分分为焦虑和(或)抑郁(anxiety and/or depression,AD)组41例和无焦虑抑郁(non-anxiety and non-depression,NAD)组62例。检测外周血辅助性T细胞17(T helper cell 17,Th17)、调节T细胞(regulatory T cells,Tregs)百分比,计算Th17细胞绝对值;检测血清炎症因子,并分析组间差异及相关性。结果三组间Th17细胞百分比、Th17细胞绝对数、Th17/Treg、白细胞介素-2(interleukin-2,IL-2)、IL-6、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)水平的差异有统计学意义(均P<0.001),AD组高于HC组和NAD组(均P<0.05),HC组和NAD组间差异无统计学意义(均P>0.05)。以上指标与焦虑、抑郁的严重程度无显著相关性(P>0.05)。Tregs百分比、IL-4、IL-10水平在各组间差异无统计学意义(均P>0.05)。女性肺结节患者焦虑和(或)抑郁比例高于男性(P<0.05)。结论肺结节患者易出现不同程度的焦虑、抑郁的情绪变化,进而导致机体出现免疫功能失调和低级别炎症。 展开更多
关键词 肺结节 焦虑 抑郁 免疫细胞 炎症
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Targeted Sub-Attomole Cancer Biomarker Detection Based on Phase Singularity 2D Nanomaterial-Enhanced Plasmonic Biosensor 被引量:1
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作者 Yuye Wang Shuwen Zeng +11 位作者 Aurelian Crunteanu Zhenming Xie Georges Humbert Libo Ma yuanyuan wei Aude Brunel Barbara Bessette Jean-Christophe Orlianges Fabrice Lalloué Oliver GSchmidt Nanfang Yu Ho-Pui Ho 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第6期284-294,共11页
Detection of small cancer biomarkers with low molecular weight and a low concentration range has always been challenging yet urgent in many clinical applications such as diagnosing early-stage cancer,monitoring treatm... Detection of small cancer biomarkers with low molecular weight and a low concentration range has always been challenging yet urgent in many clinical applications such as diagnosing early-stage cancer,monitoring treatment and detecting relapse.Here,a highly enhanced plasmonic biosensor that can overcome this challenge is developed using atomically thin two-dimensional phase change nanomaterial.By precisely engineering the configuration with atomically thin materials,the phase singularity has been successfully achieved with a significantly enhanced lateral position shift effect.Based on our knowledge,it is the first experimental demonstration of a lateral position signal change>340μm at a sensing interface from all optical techniques.With this enhanced plasmonic effect,the detection limit has been experimentally demonstrated to be 10^(-15) mol L^(−1) for TNF-α cancer marker,which has been found in various human diseases including inflammatory diseases and different kinds of cancer.The as-reported novel integration of atomically thin Ge_(2)Sb_(2)Te_(5) with plasmonic substrate, which results in a phase singularity and thus a giant lateral position shift, enables the detection of cancer markers with low molecular weight at femtomolar level. These results will definitely hold promising potential in biomedical application and clinical diagnostics. 展开更多
关键词 2D nanomaterials Cancer marker detection Phase singularity Surface plasmon
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Research on China’s technology lists for addressing climate change
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作者 Can Wang Jianhui Cong +15 位作者 Ke Wang Yue Qi Wenjian Cai Yulong Li Sha Fu Wentao Wang yuanyuan wei Xinzhu Zheng Jiani Jiang Mingpeng Chen Wenling Liu Yongxiang Zhang Zhibing Tian Ji Chen Rui Li Haiqing Zuo 《Chinese Journal of Population,Resources and Environment》 2021年第2期151-161,共11页
The compilation of technology lists addressing climate change has a guiding effect on promoting technological research and development,demonstration,and popularization.It is also crucial for China to strengthen ecolog... The compilation of technology lists addressing climate change has a guiding effect on promoting technological research and development,demonstration,and popularization.It is also crucial for China to strengthen ecological civilization construction,achieve the carbon emission peak and carbon neutrality target,and enhance global climate governance capabilities.This study first proposes the existing classification outline of the technology promotion lists,technology demand lists,and future technology lists.Then,different methodologies are integrated on the basis of the existing outline of four technology lists:China’s existing technological promotion list for addressing climate change,China’s demand list for climate change mitigation technology,China’s key technology list for addressing climate change,and China’s future technology list for addressing climate change.What’s more,core technologies are analyzed in the aspects of technology maturity,carbon reduction cost,carbon reduction potential,economic benefits,social influence,uncertainty,etc.The results show that:key industries and sectors in China already have relatively mature mitigation/adaptation technologies to support the achievement of climate change targets.The multi-sectoral system of promoting climate friendly technologies has been established,which has played an active role in tackling climate change.Currently,climate technology needs are concentrated in the traditional technology and equipment upgrading,renewable energy technology,and management decision-making support technology.The key technologies are concentrated in 3 major areas and 12 technological directions that urgently need a breakthrough.For carbon emmission peak and nentrality,carbon depth reduction and zero carbon emissions and geoengineering technology(CDR and SRM)have played an important role in forming the structure of global emissions and achieving carbon neutrality in the future.Thus,the uncertainty assessment for the comprehensive technology cost effectiveness,technology integration direction,technical maturity,ethics and ecological impacts is supportive to the national technology strategy.Finally,the presented study proposes several policy implications for medium-and long-term technology deployment,improving technology conversion rate,promoting the research and development of core technologies,and forming a technology list collaborative update and release mechanism. 展开更多
关键词 Technology for addressing climate change Technology list Carbon emission peak Carbon neutrality Key technology
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Research Progress of Cell Wall Breaking Technology and Its Application in Eucommia ulmoides Male Flower Tea
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作者 yuanyuan wei Xiao WEN +1 位作者 weiye LI Huazhong YU 《Medicinal Plant》 CAS 2018年第6期54-56,共3页
Eucommia ulmoides male flowers are rich in secondary metabolite,which have anti-tumor,sedative hypnotic,hypotensive,hypolipidemic,anti-fatigue,bacteriostatic,antioxidant and anti-aging effects.The conventional process... Eucommia ulmoides male flowers are rich in secondary metabolite,which have anti-tumor,sedative hypnotic,hypotensive,hypolipidemic,anti-fatigue,bacteriostatic,antioxidant and anti-aging effects.The conventional processing of E.ulmoides male flowers leads to the loss of nutrients and active ingredients.In recent years,cell wall breaking technology has been developed and utilized in various fields such as traditional Chinese medicine,good,chemical industry and biology.In order to promote the development of the E.ulmoides industry,the cell wall breaking technology and its characteristics are reviewed,and the application advantages of the cell wall breaking technology in the male flowers of E.ulmoides are discussed,and the prospect of the cell wall breaking of E.ulmoides is proposed in this article. 展开更多
关键词 Cell WALL BREAKING TECHNOLOGY E.ulmoides MALE FLOWER TEA Pollen WALL BREAKING E.ulmoides MALE FLOWER WALL BREAKING
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Tumor microenvironment-activatable neuropeptide-drug conjugates enhanced tumor penetration and inhibition via multiple delivery pathways and calcium deposition
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作者 Yi Cao Xiaojiao Ge +3 位作者 yuanyuan wei Lulu He Aiguo Wu Juan Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第4期292-297,共6页
Peptide-drug conjugates have achieved considerable development and application as a novel strategy for targeted delivery of anticancer drugs. Bioactive peptides induced calcium deposition can irreversibly assist inhib... Peptide-drug conjugates have achieved considerable development and application as a novel strategy for targeted delivery of anticancer drugs. Bioactive peptides induced calcium deposition can irreversibly assist inhibition of tumors. However, active regulation of calcium level through signal transduction of bioactive substances has not been reported yet. In this study, novel neuropeptide-doxorubicin conjugates(NP-DOX) with lysosome-specific acid response were described for neuropeptide Y_1 receptor(Y_1R)-overexpressed triple-negative breast cancer. The delivery mechanism of NP-DOX was clarified that diverse pathways were involved, including intracellular and intercellular transport. Importantly, up-regulation of Y_1 R-mediated intracellular calcium level via second messenger inositol triphosphate was presented in NP-DOX treated MDA-MB-231 cells. In vivo antitumor efficacy demonstrated that NP-DOX showed less organ toxicity and enhanced tumor inhibition benefited from its controlled release and Y_1R-mediated calcium deposition, compared with free DOX. This bioconjugate is a proof-of-concept confirming that neuropeptide-mediated control of signaling responses in neuropeptide-drug conjugates enables great potential for further applications in tumor chemotherapy. 展开更多
关键词 Neuropeptide-drug conjugate Tumor penetration Calcium deposition Tumor inhibition Triple-negative breast cancer
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Equilibrium electron beam parameters of the High Energy Photon Source
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作者 Haisheng Xu Cai Meng +28 位作者 Yuemei Peng Saike Tian Na Wang Xiaohao Cui Chongchong Du Zhe Duan yuanyuan Guo Ping He Xiyang Huang Daheng Ji Hongfei Ji Yi Jiao Jingyi Li Nan Li Xiaoyu Li Xiaohan Lu Pengfei Liang weimin Pan Huamin Qu Bin Wang Jiuqing Wang yuanyuan wei Jinyu Wan Gang Xu Fang Yan Chenghui Yu Sen Yue Xiang Zhang Yaliang Zhao 《Radiation Detection Technology and Methods》 CSCD 2023年第2期279-287,共9页
Purpose The physics design of the High Energy Photon Source(HEPS)was finished after many times of iteration.Hereby,the typical equilibrium electron beam parameters corresponding to the proposed two baseline operation ... Purpose The physics design of the High Energy Photon Source(HEPS)was finished after many times of iteration.Hereby,the typical equilibrium electron beam parameters corresponding to the proposed two baseline operation modes in the baseline design of HEPS are presented.Methods To compute the equilibrium parameters of the electron beam,the lattice parameters,RF parameters,and the parameters of the insertion devices(IDs)were determined first.Furthermore,it is more precise to use the full-current electron beam parameters in the estimations of the performance of the synchrotron light.Therefore,not only the single-particle dynamics but also the current-dependent collective effects need to be considered in the computations of the full-current,equilibrium parameters of the electron beam.Both analytic computations and multi-particle tracking simulations were carried out.Results The full-current,equilibrium parameters of the electron beams in the HEPS storage ring are presented in this paper.Moreover,the main beam parameters in the injector(the booster and the LINAC),corresponding to the two baseline operation modes of the storage ring,are also presented.Conclusion The typical electron beam parameters corresponding to the two baseline operation modes are given in detail in this paper. 展开更多
关键词 High Energy Photon Source Electron beam parameters
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基于物联网的草牧业管理决策系统在呼伦贝尔农垦的应用 被引量:5
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作者 孙丙宇 贾秀芳 +4 位作者 黄河 魏圆圆 周林立 方薇 严曙 《科学通报》 EI CAS CSCD 北大核心 2018年第17期1703-1710,共8页
我国大中型草牧场目前普遍存在三方面的问题:管理粗放,无法科学合理地进行农牧业生产安排;缺乏市场信息指导生产计划,不能适应市场实际需求;市场信息不对称、高品质产品卖不出高价格、无法定向定量生产和销售.本文以呼伦贝尔农垦集团现... 我国大中型草牧场目前普遍存在三方面的问题:管理粗放,无法科学合理地进行农牧业生产安排;缺乏市场信息指导生产计划,不能适应市场实际需求;市场信息不对称、高品质产品卖不出高价格、无法定向定量生产和销售.本文以呼伦贝尔农垦集团现代草牧业生产过程为案例,设计了基于物联网的现代草牧业精准生产管理指挥决策系统解决方案.该方案由大数据云计算平台、草牧业生产管理决策信息系统、草牧业精准作业技术与装备系统、电子商务和全程追溯系统四部分组成.从优化草牧业种植结构,实施"减施增效"施肥方案,确定产品销售品种与区域,协调调度人员、设备、物资、农机等生产要素等方面指导草牧业生产全过程,从而全面提升呼伦贝尔农垦集团信息化水平,最终助力现代草牧业生产模式转型升级.该管理决策系统对全国草牧业的生产管理均有借鉴作用. 展开更多
关键词 草牧业 决策系统 信息化 智能化 大数据
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Phosphomolybdic acid-modified highly organized TiO2 nanotube arrays with rapid photochromic performance 被引量:3
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作者 yuanyuan wei Bing Han +1 位作者 Zhaojun Dong wei Feng 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2019年第9期1951-1958,共8页
TiO2 nanotube arrays were prepared by means of an electrochemical anodization technique in an organic electrolyte solution doped with polyvinyl pyrrolidone (PVP) and were subsequently modified with phosphomolybdic aci... TiO2 nanotube arrays were prepared by means of an electrochemical anodization technique in an organic electrolyte solution doped with polyvinyl pyrrolidone (PVP) and were subsequently modified with phosphomolybdic acid (PMoA) to obtain PMoA/TiO2 nanotube arrays. The microstructure and photochromic properties were investigated via X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-vis), and X-ray photoelectron spectroscopy (XPS). The results indicated that the Keggin structure of PMoA and the nanotube structure of TiO2 were not destroyed, and there was a strong degree of interaction between PMoA and TiO2 at the biphasic interface with lattice interlacing during the compositing process. The XPS results further indicated that there was a change in the chemical microenvironment during the formation process of the composite, and a new charge transfer bridge was formed through the Mo-O-Ti bond. Under visible light irradiation, the colorless PMoA/TiO2 nanotube array quickly turned blue and exhibited a photochromic response together with reversible photochromism in the presence of H2O2. After visible light irradiation for 60s, the appearance of Mo^5+ species in the XPS spectra indicated a photoreduction process in accordance with a photoinduced electron transfer mechanism. 展开更多
关键词 Phosphomolybdic acid TiO2 NANOTUBE array RAPID PHOTOCHROMIC PERFORMANCE
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The transfer line design for the HEPS project 被引量:3
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作者 yuanyuan wei Yuemei Peng +1 位作者 Gang Xu yuanyuan Guo 《Radiation Detection Technology and Methods》 CSCD 2020年第4期440-447,共8页
Purpose The high energy photon source(HEPS),a 6-GeV synchrotron radiation facility with ultralow emittance,is under construction in China.Three transfer lines are designed for HEPS.One low-energy transfer line is used... Purpose The high energy photon source(HEPS),a 6-GeV synchrotron radiation facility with ultralow emittance,is under construction in China.Three transfer lines are designed for HEPS.One low-energy transfer line is used to deliver the 500 MeV beam provided by the linac to the booster.Two high-energy transfer lines are used to connect the booster and the storage ring to realize beam accumulation in the booster at 6 GeV.Method The design of the transfer lines is closely related to the layout and optics design of the storage ring,booster and linac.Based on the physics design of the storage ring,booster and linac,the design of the transfer lines has been adjusted.Results and conclusion In this paper,the considerations and design of the latest lattice of transfer lines are described.The design satisfies the requirements of the high efficiency transmission and injection. 展开更多
关键词 HEPS Transfer lines OPTICS Error study
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Spatial–temporal variations of NDVI and its response to climate in China from 2001 to 2020
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作者 yuanyuan wei Shougang Sun +1 位作者 Dong Liang Zhaohong Jia 《International Journal of Digital Earth》 SCIE EI 2022年第1期1463-1484,共22页
Vegetation plays an important role in global or regional environmental change.In this study,the spatial–temporal variations of NDVI and its response to climate in China and its seven sub-regions were investigated bas... Vegetation plays an important role in global or regional environmental change.In this study,the spatial–temporal variations of NDVI and its response to climate in China and its seven sub-regions were investigated based on MODIS NDVI data,ERA5-land precipitation(PRE)and temperature(TEM)data from 2001 to 2020.The inter-annual growth rate of NDVI in China was 0.0021/yr in the past 20 years.The inter-annual growth rates of NDVI in seven sub-regions had significant differences at regional or seasonal scales.The ratio of improved vegetation area to the total studied area reached about 70%.In summer,vegetation degradation was concentrated in East China and Southwest China.The vegetation in Central China and South China improved more obviously in autumn than in the other seasons.The vegetation of Northeast China had a remarkable degradation in autumn and winter,especially in winter.The influence degree of PRE(q=0.54,P<0.01)was greater than that of TEM(q=0.27,P<0.01)in the control of the spatial distribution of NDVI.The interaction influence degree q of PRE∩TEM was about 0.71 in the last 20 years.However,the PRE and TEM played different roles in vegetation growth in seven sub-regions. 展开更多
关键词 NDVI spatial–temporal variations climate change MK test Geodetector
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A satellite-derived,ground-measurement-independent monthly PM_(2.5)mass concentration dataset over China during 2000-2015
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作者 Ying Zhang Zhengqiang Li +1 位作者 yuanyuan wei Zongren Peng 《Big Earth Data》 EI 2022年第4期633-649,共17页
Following the accelerated development of urbanization and industrialization,atmospheric particulate matter has become a significant threat to public health globally.Environmental health studies usually use the mass co... Following the accelerated development of urbanization and industrialization,atmospheric particulate matter has become a significant threat to public health globally.Environmental health studies usually use the mass concentration of fine particles(PM_(2.5))as a base data to predict the health risks of particulate exposure.However,PM_(2.5)data from ground monitoring stations in China has not been provided until January 2013 by the Ministry of Environmental Protection of China.Hence,an alternative dataset of PM_(2.5)spatiotemporal distributions extending to years earlier than 2013 is urgently needed,which is of great significance to atmospheric environment assessment and pollution prevention and control.Atmospheric aerosol products by the moderate-resolution imaging spectroradiometer(MODIS)have been released since 2000,which provides the possibility to reconstruct historical PM_(2.5).However,most current methods do not have the ability to estimate PM_(2.5)mass concentration independently of ground observations.The PM_(2.5)mass concentration data set produced by PM_(2.5)remote sensing(PMRS)model based on physical processes does not depend on the ground observations,and also is not affected by the uncertainty of model emission sources or the completeness of chemical reaction mechanism.These ensure that the point-by-point validation for PM_(2.5)mass concentration data is more convincing,and the dataset can also be further used for model assimilation and artificial intelligence training to improve their predictions.In this study,we calculate the monthly PM_(2.5)mass concentration near the ground over land of China using aerosol inversion products(aerosol optical depth and fine-mode fraction)of MODIS and meteorological data(boundary layer height&relative humidity)provided by the Modern-Era Retrospective Analysis for Research and Applications Version 2(MERRA-2)data set.The results show that,in China,6 pollution centers mainly concentrated in the central and eastern regions.The highest PM_(2.5)mass concentration occurred in winter,whereas the pollution range was larger in summer.There are 63.4%of validation sites with biases within±20μg m−3,and the expected error is as±(15μg m−3+30%)enveloped by the monthly mean PM_(2.5)mass concentrations.The monthly PM_(2.5)is stored as NETCDF format,with a spatial resolution of 1°×1°.The published data is available in http://www.dx.doi.org/10.11922/sciencedb.j00076.00061. 展开更多
关键词 PM_(2.5) data set satellitederived China MONTHLY
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Research on the slow orbit feedback of BEPCⅡusing machine learning
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作者 Yu Bai yuanyuan wei +2 位作者 weibin Liu Gang Xu Jiuqing Wang 《Radiation Detection Technology and Methods》 CSCD 2022年第2期179-186,共8页
Background:Long-term orbit stability is a key performance indicator in synchrotron radiation facilities and colliders nowa-days,in which the orbit correction and corresponding slow orbit feedback system are indispensa... Background:Long-term orbit stability is a key performance indicator in synchrotron radiation facilities and colliders nowa-days,in which the orbit correction and corresponding slow orbit feedback system are indispensable.Conventional method of orbit correction uses response matrix based on SVD algorithm,which becomes less effective after a long operation due to the fact that response matrix measurements cannot be taken during normal operation.Purpose:The purpose of this paper is to integrate machine learning model into the slow orbit feedback process and to automatically update the model online to better correct the orbit shifts.Methods:In this paper,we propose a method for slow orbit feedback of storage ring based on machine learning.Training the neural networks by using online data sets,which can establish the mapping relation between BPMs and correctors,and being updated automatically,without using extra time to remeasure the response matrix.Results:The experiments in this paper are all conducted and verified in the upgrading project of Beijing Electron-Positron Collider.By the way of learning automatically,the updated neutral network is closer to the real machine model,and the orbit after correction shows a smaller fluctuation relative to the golden orbit.Conclusion:Using the online data sets which reflect the response of orbit to correctors in real time to update the neural network can increase the orbit stability. 展开更多
关键词 Orbit correction Machine learning Slow orbit feedback Learning automatically
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Satellite remote sensing of atmospheric particulate matter mass concentration:Advances,challenges,and perspectives
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作者 Ying Zhang Zhengqiang Li +15 位作者 Kaixu Bai yuanyuan wei Yisong Xie Yuanxun Zhang Yang Ou Jason Cohen Yuhuan Zhang Zongren Peng Xingying Zhang Cheng Chen Jin Hong Hua Xu Jie Guang Yang Lv Kaitao Li Donghui Li 《Fundamental Research》 CAS 2021年第3期240-258,共19页
Mapping the mass concentration of near-surface atmospheric particulate matter(PM)using satellite observations has become a popular research niche,leading to the development of a variety of instruments,algorithms,and d... Mapping the mass concentration of near-surface atmospheric particulate matter(PM)using satellite observations has become a popular research niche,leading to the development of a variety of instruments,algorithms,and datasets over the past two decades.In this study,we conducted a holistic review of the major advances and challenges in quantifying PM,with a specific focus on instruments,algorithms,datasets,and modeling methods that have been developed over the past 20 years.The aim of this study is to provide a general guide for future satellite-based PM concentration mapping practices and to better support air quality monitoring and management of environmental health.Specifically,we review the evolution of satellite platforms,sensors,inversion algorithms,and datasets that can be used for monitoring aerosol properties.We then compare various practical methods and techniques that have been used to estimate PM mass concentrations and group them into four primary categories:(1)univariate regression,(2)chemical transport models(CTM),(3)multivariate regression,and(4)empirical physical approaches.Considering the main challenges encountered in PM mapping practices,for example,data gaps and discontinuity,a hybrid method is proposed with the aim of generating PM concentration maps that are both spatially continuous and have high precision. 展开更多
关键词 Satellite remote sensing Particulate matter Aerosol optical depth Air quality monitoring Environmental modeling
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