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| 1 | Comparison of Some Vegetation Indices in Seasonal Information显示文摘With the development of vegetation indices, the reflection capability of vegetation indices to the state of vegetation has been improved in various degrees. Especially, the vegetation index of Terra/MODIS-EVI is believed to have the highest sensitivity to the seasonality of vegetation. This study compares the reflection susceptibility of three vegetation indices (NOAA/AVHRR-NDVI, Terra/MODIS-NDVI and Terra/MODIS-EVI) to the seasonal variations of vegetation in the mid-south of Yunnan Province of China. It has been found that Terra/MODIS-EVI does best in the elimination of external disturbance. Firstly, it obviously improves the linear relationship with vegetation cover degree, especially in the high vegetation coverage area. Secondly, it avoids the emergence of vegetation index saturation. Thirdly, it reduces the environmental influence including both effects of atmosphere and soil. So it is believed that the Terra/MODIS-EVI can offer excellent tool for quantitative research of remote sensing, and has realized to be oriented by data with high quality. | HAO Chengyuan WU Shaohong XU Chuanyang | 2008 | Chinese Geographical Science2008，18，3： | 3 |
| 2 | ASAF: altered spontaneous activity fingerprinting in Alzheimer’s disease based on multisite fMRI显示文摘Several monocentric studies have noted alterations in spontaneous brain activity in Alzheimer's disease (AD), although there is no consensus on the altered amplitude of low-frequency fluctuations in AD patients. The main aim of the present study was to identify a reliable and reproducible abnormal brain activity pattern in AD. The amplitude of local brain activity (AM), which can provide fast mapping of spontaneous brain activity across the whole brain, was evaluated based on multisite rs-fMRI data for 688 subjects (215 normal controls (NCs), 221 amnestic mild cognitive impairment (aMCI) 252 AD). Two-sample t-tests were used to detect group differences between AD patients and NCs from the same site. Differences in the AM maps were statistically analyzed via the Stouffer's meta-analysis. Consistent regions of lower spontaneous brain activity in the default mode network and increased activity in the bilateral hippocampus/parahippocampus, thalamus, caudate nucleus, orbital part of the middle frontal gyrus and left fusiform were observed in the AD patients compared with those in NCs. Significant correlations (P? | Jiachen Li Dan Jin Ang Li Bing Liu Chengyuan Song Pan Wang Dawei Wang Kaibin Xu Hongwei Yang Hongxiang Yao Bo Zhou Alexandre Bejanin Gael Chetelat Tong Han Jie Lu Qing Wang Chunshui Yu Xinqing Zhang Yuying Zhou Xi Zhang Tianzi Jiang Yong Liu Ying Han | 2019 | Science Bulletin2019，64，14： | 3 |
| 3 | The first discovery of Permian conodont fauna from peri-Gondwana cool water facies in Tibet,China显示文摘The Angjie Formation and Xiala Formation,present in the Shiquanhe area of Gar County in the western part of Gangdise,Tibet,belong to the Gangdise stratigraphic subregion. Conodonts have been found in the Angjie Formation,and they permit an age determination of Early to Middle Permian for that formation. The age of the Xiala Formation could be late Middle Permian. Whether the Late Permian marine deposits are present in this area still needs to be determined,but it is possible that the lower part of the Xiala Formation overlaps partly the upper part of the Angjie Formation. More importantly,the study has brought about a finding of typical peri-Gondwana cool water facies conodonts,namely,Vjalovognathus sp. nov. x. This is the first report and brief description of a conodont fauna from peri-Gondowana cool water facies in China. It indicates that the Gangdise stratigraphic subregion can be subdivided;the western part belongs to peri-Gondwana cool water facies,and the eastern part belongs to Tethys. | ZHENG YouYe XU RongKe WANG ChengYuan MA GuoTao | 2007 | Chinese Science Bulletin2007，52，9： | 3 |
| 4 | Arabidopsis ENOR3 regulates RNAi-mediated antiviral defense显示文摘Viruses can infect host plants to cause severe diseases and substantial agricultural loss, while plants have evolved RNA interference(RNAi) strategy to defend against viral infection. Despite enormous efforts, only a few host proteins in RNAi pathway were shown to mediate antiviral defense, including RNA-dependent RNA polymerase 1(RDR1), RDR6, DICER-LIKE 2(DCL2) and DCL4. In this study, we carried out a genetic screen for antiviral factors of RNAi pathway in Arabidopsis rdr6 background via inoculation with a 2 bdeficient Cucumber Mosaic Virus(CMV-D2b). We identified a mutant susceptible to CMV-D2b, referred to as enhancer of rdr6(enor) 3-1 rdr6, and found that ENOR3 encodes a functionally unknown protein with high homology to the mammalian Non Imprinted in Prader-Willi/Angelman(NIPA) magnesium transporters. ENOR3 inhibits accumulation of CMV-D2b and acts additively with RDR1, RDR6, DCL2 and DCL4 in antiviral defense. These results uncover that ENOR3 is a key component in antiviral RNAi pathway, and provide new insights into antiviral immunity. | Hua Gao Mai Yang Haitao Yang Yue Qin Biyun Zhu Gang Xu Chengyuan Xie Dewei Wu Xiaolin Zhang Wanxiang Li Jianbin Yan Susheng Song Tiancong Qi Shou-Wei Ding Daoxin Xie | 2018 | Journal of Genetics and Genomics2018，45，1： | 2 |
| 5 | Carbon isotopic record from Upper Devonian carbonates at Dongcun in Guilin, southern China, supporting the world- wide pattern of carbon isotope excursions during Frasnian-Famennian transition显示文摘Two positive d 13C excursions are presented in records from the Frasnian-Famennian (F-F) marine carbon-ate sediments in Europe, America, Africa, and Australia, having been considered as a worldwide pattern, and attrib-uted to enhanced organic carbon burial during the F-F biological mass extinction. However, this worldwide pattern has not been revealed from the well-deposited Late Devonian sequences in southern China. In this paper, a detailed inves-tigation has been made on the Late Devonian section at Dongcun, Guilin, southern China to constrain perturbations in d 13C of carbonates in the F-F deposited sequence. The result from this section also indicates two positive d 13C ex-cursions during the F-F transition. The first excursion with an amplitude of 1.5 occurred at the bottom of linguiformis Zone, later than the early excursion existing in the Late rhe-nana Zone of the Late Devonian profiles in other continents, especially, in central Europe. This difference has been ex-pected to be a result as conodont Palmatolepis linguiformis occurred earlier in southern China than other sites. The second excursion with an amplitude of 2.1 is located at the F-F boundary, same as the records from other continents. This result strongly supports the view that two carbon iso-tope positive excursions during the F-F transition are com-mon in carbonate sediments, resulting from worldwide in-creases of organic carbon burial intensity. | XU Bing GU Zhaoyan LIU Qiang WANG Chengyuan LI Zhenliang | 2003 | Chinese Science Bulletin2003，48，12： | 2 |
| 6 | Phenotypic plasticity rather than locally adapted ecotypes allows the invasive alligator weed to colonize a wide range of habitats显示文摘 | GENG Yupeng PAN Xiaoyun XU Chengyuan | 2007 | Biological Invasions2007，9，3： | 1 |
| 7 | Genetic diversity of alligator weed in China by RAPD analysis显示文摘 | XU Chengyuan ZHANG Wenju FU Cuizhang | 2003 | Biodiversity and Conservation2003，12，4： | 1 |
| 8 | Genetic diversity of alligator weed in China by RAPD analysis显示文摘 | Xu Chengyuan Zhang Wenju Fu Cuizhang | 2003 | Biodiversity-and-Conservation2003，12，4： | 1 |
| 9 | Reconstruction and prediction of capillary pressure curve based on Particle Swarm Optimization-Back Propagation Neural Network method显示文摘Capillary pressure curve plays a critical role in the reservoir evaluation.It is essential to reconstruct and predict capillary pressure curve properly.Many traditional capillary pressure correlations have been suggested in the literature.However,their major limitation is mainly applicable to homogenous reservoir,and the larger error will be caused when heterogeneous reservoir is dealt by using these mathematical correlations.This study aims at providing an important method based on Particle Swarm Optimization-Back Propagation Neural Network(PSO-BP neural network)to represent and predict capillary pressure curve for homogenous and heterogeneous reservoir.The combination of PSO algorithm and BP neural network converges quickly,which improves the accuracy and efficiency of simulation.In this paper,core samples from three blocks of the same marine-sand reservoir,whose porosity is between 0.6%and 20.0%and permeability is between 0.1mD and 6117mD,are investigated by PSO-BP neural network method and J-Function method respectively.The reconstruction and prediction results are compared with the results obtained by mercury intrusion method in laboratory.The results show that capillary pressure curves reconstructed and predicted by PSO-BP neural network method are in better agreement with mercury intrusion curves than J-Function method,with 0.1%e5%and 5%e8%relative error respectively,which can totally meet the in-situ requirements.It is also demonstrated that PSO-BP neural network method is more suitable for homogenous and heterogeneous reservoir.©2018 Southwest Petroleum University. | Lijun You Qigui Tan Yili Kang Chengyuan Xu Chong Lin | 2018 | Petroleum2018，4，3： | 1 |
| 10 | Impact of inactivated COVID-19 vaccines on viral shedding in B.1.617.2(Delta)variant-infected patients显示文摘Dear Editor,The coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-COV-2)has waged a global pandemic. As of April 15, 2022, more than 500 million cases of COVID-19 had been reported, with more than 6 million deaths. The ultimate arsenal to fight against this pandemic is highly effective vaccines (Bok et al.,2021;Sadarangani et al., 2021). | Zhiliang Hu Yi Yin Kai Wang Miaomiao Xu Chengyuan Ding Yan Song Changhua Yi Junwei Li Yongxiang Yi Zhihang Peng | 2022 | Science China(Life Sciences)2022，65，12： | 0 |
| 11 | High-rate CH_(4)-to-C_(2)H_(6) photoconversion enabled by Au/ZnO porous nanosheets under oxygen-free system显示文摘Photocatalytic CH_(4) coupling into high-valued C_(2)H_(6) is highly attractive,whereas the photosynthetic rate,especially under oxygen-free system,is still unsatisfying.Here,we designed the negatively charged metal supported on metal oxide nanosheets to activate the inert C-H bond in CH_(4)and hence accelerate CH_(4) coupling performance.As an example,the synthetic Au/ZnO porous nanosheets exhibit the C_(2)H_(6) photosynthetic rate of 1,121.6μmol g^(-1)_(cat)h^(-1)and the CH_(4) conversion rate of 2,374.6μmol g^(-1)_(cat)h^(-1) under oxygen-free system,2 orders of magnitude higher than those of previously reported photocatalysts.By virtue of several in situ spectroscopic techniques,it is established that the generated Au^(δ-)and O^-species together polarized the C-H bond,while the Au^(δ-)and O^-species jointly stabilized the CH_(3) intermediates,which favored the coupling of CH_(3) intermediate to photosynthesize C_(2)H_(6) instead of overoxidation into CO_(x).Thus,the design of dual active species is beneficial for achieving high-efficient CH_(4)-to-C_(2)H_(6) photoconversion. | Kai Zheng Xiaojing Zhang Jun Hu Chengbin Xu Juncheng Zhu Jing Li Mingyu Wu Shan Zhu Li Li Shumin Wang Yumei Lv Xin He Ming Zuo Chengyuan Liu Yang Pan Junfa Zhu Yongfu Sun Yi Xie | 2024 | Science China Chemistry2024，67，3： | 0 |
| 12 | An investigation on the best-fit models for sugarcane biomass estimation by linear mixedeffect modelling on unmanned aerial vehicle-based multispectral images:A case study of Australia显示文摘Due to the worldwide population growth and the increasing needs for sugar-based products,accurate estimation of sugarcane biomass is critical to the precise monitoring of sugarcane growth.This research aims to find the imperative predictors correspond to the random and fixed effects to improve the accuracy of wet and dry sugarcane biomass estimations by integrating ground data and multi-temporal images from Unmanned Aerial Vehicles(UAVs).The multispectral images and biomass measurements were obtained at different sugarcane growth stages from 12 plots with three nitrogen fertilizer treatments.Individual spectral bands and different combinations of the plots,growth stages,and nitrogen fertilizer treatments were investigated to address the issue of selecting the correct fixed and random effects for the modelling.A model selection strategy was applied to obtain the optimum fixed effects and their proportional contribution.The results showed that utilizing Green,Blue,and Near Infrared spectral bands on models rather than all bands improved model performance for wet and dry biomass estimates.Additionally,the combination of plots and growth stages outperformed all the candidates of random effects.The proposed model outperformed the Multiple Linear Regression(MLR),Generalized Linear Model(GLM),and Generalized Additive Model(GAM)for wet and dry sugarcane biomass,with coefficients of determination(R2)of 0.93 and 0.97,and Root Mean Square Error(RMSE)of 12.78 and 2.57 t/ha,respectively.This study indicates that the proposed model can accurately estimate sugarcane biomasses without relying on nitrogen fertilizers or the saturation/senescence problem of Vegetation Indices(VIs)in mature growth stages. | Sharareh Akbarian Chengyuan Xu Weijin Wang Stephen Ginns Samsung Lim | 2023 | Information Processing in Agriculture2023，10，3： | 0 |
| 13 | Structural formation and evolution mechanisms of fracture plugging zone显示文摘A coupled CFD-DEM method is used to simulate the formation process of fracture plugging zone.A photo-elastic system characterizing mesoscale force chain network developed by our own is used to model the pressure evolution in fracture plugging zone to reveal the evolution mechanism of the structure of fracture plugging zone.A theoretical basis is provided for improving the lost circulation control effect in fractured reservoirs and novel methods are proposed for selecting loss control materials and designing loss control formula.CFD-DEM simulation results show that bridging probability is the key factor determining the formation of fracture plugging zone and fracture plugging efficiency.Critical and absolute bridging concentrations are proposed as the key indexes for loss control formula design.With the increase of absolute bridging concentration,the governing factor of bridging is changed from material grain size to the combination of material grain size and friction force.Results of photo-elastic experiments show that mesoscale force chain network is the intrinsic factor affecting the evolution of pressure exerting on the fracture plugging zone and determines the macroscopic strength of fracture plugging zone.Performance parameters of loss control material affect the force chain network structure and the ratio of stronger force chain,and further impact the stability and strength of fracture plugging zone.Based on the study results,the loss control formula is optimized and new-type loss control material is designed.Laboratory experiments results show that the fracture plugging efficiency and strength is effectively improved. | XU Chengyuan ZHANG Jingyi KANG Yili XU Feng LIN Chong YAN Xiaopeng JING Haoran SHANG Xiangyu | 2021 | Petroleum Exploration and Development2021，48，1： | 0 |
| 14 | Experimental study on the controlling factors of frictional coefficient for lost circulation control and formation damage prevention in deep fractured tight reservoir显示文摘Working fluids loss is a major contributor to low productivity during production process of fractured tight reservoirs.Lost circulation control effect directly related to the tribological behavior between fracture surface and lost circulation materials(LCMs).In this study,the friction coefficient(FC)was investigated using typical clastic rocks and LCMs by considering multiple effect factors divided into external condition and internal condition.The results show that normal load had a relatively high effect on sliding model.A positive correlation was observed between FC and asperities heights.FC decreased induced by particle size degradation of rigid LCMs.Elastic LCMs manifested higher FC compared with rigid LCMs.Under the lubrication condition by working fluid,FC of rigid LCMs was mainly controlled by their surface wettability.FC of organic LCMs is more sensitive to high temperature aging than inorganic LCMs.Fracture plugging experiments show that LCMs optimized based on the research results can effectively improve the efficiency and strength of fracture plugging. | Chengyuan Xu Honglin Zhang Mingming Zhu Yili Kang Xiaopeng Yan Jingyi Zhang Yingrui Bai | 2022 | Petroleum2022，8，3： | 0 |
| 15 | A recently evolved BAHD acetyltransferase,responsible for bitter soyasaponin A production,is indispensable for soybean seed germination显示文摘Soyasaponins are major small molecules that accumulate in soybean(Glycine max)seeds.Among them,type-A soyasaponins,fully acetylated at the terminal sugar of their C22 sugar chain,are responsible for the bitter taste of soybean-derived foods.However,the molecular basis for the acetylation of type-A soyasaponins remains unclear.Here,we identify and characterize Gm SSAc T1,encoding a BADH-type soyasaponin acetyltransferase that catalyzes three or four consecutive acetylations on type-A soyasaponins in vitro and in planta.Phylogenetic analysis and biochemical assays suggest that Gm SSAc T1 likely evolved from acyltransferases present in leguminous plants involved in isoflavonoid acylation.Loss-of-function mutants of Gm SSAc T1 exhibited impaired seed germination,which attribute to the excessive accumulation of null-acetylated type-A soyasaponins.We conclude that Gm SSAc T1 not only functions as a detoxification gene for high accumulation of type-A soyasaponins in soybean seeds but is also a promising target for breeding new soybean varieties with lower bitter soyasaponin content. | Jia Yuan Liya Ma Yan Wang Xindan Xu Rui Zhang Chengyuan Wang Wenxiang Meng Zhixi Tian Yihua Zhou Guodong Wang | 2023 | Journal of Integrative Plant Biology2023，65，11： | 0 |
| 16 | Clinical efficacy of low-dose emetine for patients with COVID-19:a real-world study显示文摘Objective:Emetine,an isoquinoline alkaloid that is enriched at high concentrations in the lung,has shown potent in vitro activity against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).The aim of this study was to better understand the effectiveness of low-dose emetine for patients with coronavirus disease 2019(COVID-19).Methods:In this real-world study,63 patients with mild or common COVID-19 were recruited from Wuhan Fangcang Shelter Hospital and five COVID-19-designated hospitals in Anhui Province,China from February to March 2020.Thirty-nine patients from Wuhan Fangcang Shelter Hospital were assigned to a pragmatic randomized controlled clinical trial,and 24 patients from the 5 COVID-19-designated hospitals in Anhui Province underwent a real-world study.The medication course of emetine was less than 10 days.The main symptoms and adverse reactions of all patients were observed and recorded.The primary outcome measure was the time required for a negative SARS-CoV-2 RNA result or the negative result rate on day 10.Secondary outcomes included axillary temperature,transcutaneous oxygen saturation,and respiratory frequency recovery.The study was approved by the Ethics Committee of The First Affiliated Hospital of Anhui Medical University on February 20,2019(approval No.PJ2020-03-19)and was registered with the Chinese Clinical Trial Registry on February 20,2019(registration number:ChiCTR2000030022).Results:The oxygen saturation values were higher in the treatment group than in the control group on the first day after enrollment for patients treated at Fangcang Shelter Hospital.The axillary body temperature,respiratory rate,and oxygen saturation among patients in Fangcang Shelter Hospital were related to the time effect but not to the intervention measures.The respiratory rate and oxygen saturation of patients in the Anhui designated hospitals were related to the intervention measures but not to the time effect.The axillary body temperature of patients in Anhui designated hospitals was related to the time effect but not to the intervention measures.Conclusion:Our preliminary study shows that low-dose emetine combined with basic conventional antiviral drugs improves clinical symptoms in patients with mild and common COVID-19 without apparent adverse effects,suggesting that moderately increased doses of emetine may have good potential for treatment and prevention of COVID-19. | Song Fan Qi Zhen Cheng Chen Wenjun Wang Qibing Wu Huihui Ma Chengyuan Zhang Li Zhang Baojing Lu Huiyao Ge Liang Yong Bao Li Yafen Yu Weiwei Chen Yiwen Mao Guangbo Qu Li Su Aoli Wang Zhen Ding Haiwen Li Jin Zhang Yonglian Wang Yufeng Gao Xihai Xu Zhongming Zhu Jun Chen Long Zhang Hongqiang Liang Song Wu Meng Huang Quan Xia Ping Li Yehuan Sun Chaozhao Liang Wei Wei Qingsong Liu Liangdan Sun | 2021 | Journal of Bio-X Research2021，4，2： | 0 |
| 17 | Formation mechanisms of fracture plugging zone and optimization of plugging particles显示文摘As formation mechanisms of plugging zone and criteria for fracture plugging remain unclear,plugging experiments and methods testing granular material mechanical properties are used to study the formation process of the plugging zone in fractured formations,analyze composition and ratios of different sizes of particles in the plugging zone,and reveal the essence and driving energy of the formation and damage of the plugging zone.New criteria for selecting lost circulation materials are proposed.The research results show that the formation of the plugging zone has undergone a process from inertial flow,elastic flow,to quasi-static flow.The plugging zone is composed of fracture mouth plugging particles,bridging particles and filling particles,and the proportion of the three types of particles is an important basis for designing drilling fluid loss control formula.The essence of the construction of the plugging zone is non-equilibrium Jamming phase transition.The response of the plugging zone particle system to pressure is driven by entropy force;the greater the entropy,the more stable the plugging zone.Lost circulation control formula optimized according to the new criteria has better plugging effect than the formula made according to conventional plugging rules and effectively improves the pressure-bearing capacity of the plugging zone.The research results provide a theoretical and technical basis for the lost circulation control of fractured formations. | LEI Shaofei SUN Jinsheng BAI Yingrui LYU Kaihe ZHANG Shupei XU Chengyuan CHENG Rongchao LIU Fan | 2022 | Petroleum Exploration and Development2022，49，3： | 0 |
| 18 | Highly branched poly(β-amino ester)s with narrow molecular weight distribution: Fractionation and gene transfection activity显示文摘Highly branched poly(β-amino ester)s(HPAEs) have shown their great promise in gene delivery. However, their broad molecular weight distribution(MWD) poses an additional challenge to the mechanistic understanding of the influence of molecular weight(MW) on their gene transfection activity. Using a stepwise precipitation strategy, HPAEs were fractionated. It is shown that MW has a significant effect on the transfection activity and cytotoxicity of HPAEs. The intermediate MW mediates higher transfection efficiency while maintaining high cell viability. Mechanistic studies show that the intermediate MW confers stronger DNA binding affinity to HPAEs, leading to the formulation of polyplexes with a relatively smaller size and more positive zeta potential. This study not only suggests a simple strategy to fractionate HPAEs with narrow MWD but also provides new insights into understanding the structure-property relationship, which would facilitate the clinical translation of HPAEs in gene therapy. | Chenfei Wang Litao Sun Qiuxia Li Zhili Li Chengyuan Xu Xinyue Zhang Jianjun Shi Hao Zhou Wenxin Wang Dezhong Zhou | 2023 | Chinese Chemical Letters2023，34，3： | 0 |
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