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Impacts of agri-food e-commerce on traditional wholesale industry:Evidence from China

Journal of Integrative Agriculture 2024年第4期23卷 1409-1428页

作者： ruyi Yang Jifang liu Shanshan Cao Wei Sun Fantao Kong Institute of Agricultural Information Chinese Academy of Agricultural SciencesBeijing 100081China Institute of Special Animal and Plant Sciences Chinese Academy of Agricultural SciencesChangchun 130112China

Rapidly expanding studies investigate the effects of e-commerce on company operations in the retail market.However,the interaction between agri-food e-commerce(AEC)and the traditional agri-food wholesale industry(AWI)has not received enough attention in the existing literature.Based on the provincial panel data from 2013 to 2020 in China,this paper examines the effect of AEC on AWI,comprising three dimensions:digitalization(DIGITAL),agrifood e-commerce infrastructure and supporting services(AECI),and agri-food e-commerce economy(AECE).First,AWI and AEC are measured using an entropy-based combination of indicators.The results indicate that for China as a whole,AWI has remained practically unchanged,whereas AEC exhibits a significant rising trend.Second,the findings of the fixed-effect regression reveal that DIGITAL and AECE tend to raise AWI,whereas AECI negatively affects AWI.Third,threshold regression results indicate that AECI tends to diminish AWI with three-stage inhibitory intensity,which manifests as a first increase and then a drop in the inhibition degree.These results suggest that with the introduction of e-commerce for agricultural product circulation,digital development will have catfish effects that tend to stimulate the vitality of the conventional wholesale industry and promote technical progress.Furthermore,the traditional wholesale industry benefits financially from e-commerce even while it diverts part of the traditional wholesale circulation for agricultural products.

关键词： agri-food e-commerce traditional wholesale industry panel threshold model dual-channel circulation

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Phosphorous-doped carbon nanotube/reduced graphene oxide aerogel cathode enabled by pseudocapacitance for high energy and power zinc-ion hybrid capacitors

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Chinese Chemical Letters 2024年第2期35卷 570-576页

作者： Junjun Yao Fuzhi Li ruyi Zhou Chenchen Guo Xinru liu Yirong Zhu Hunan Key Laboratory of Green Metallurgy and New Energy Materials College of Materials and Advanced ManufacturingHunan University of TechnologyZhuzhou 412007China College of packaging and Material Engineering Hunan University of TechnologyZhuzhou 412007China

The design and development of energy storage device with high energy/power density has become a research hotspot.Zinc-ion hybrid capacitors(ZHCs)are considered as one of the most promising candidates.However,the application of ZHCs is hindered by their low energy density at high power density due to the unsatisfactory cathode material.In this study,a novel 3D phosphorus-doped carbon nanotube/reduced graphene oxide(P-CNT/rGO)aerogel cathode is synthesized through a synergistic modification strategy of CNT insertion and P doping modification combined with 3D porous design.The as-obtained P-CNT/rGO aerogel cathode manifests significantly increased surface aera,expanded interlayer spacing,and enhanced pseudocapacitance behavior,thus leading to significantly enhanced specific capacitance and superb ions transport performance.The as-assembled ZHC based on P-CNT/rGO cathode delivers a superior energy density of 42.2 Wh/kg at an extreme-high power density of 80 kW/kg and excellent cycle life.In-depth kinetic analyses are undertaken to prove the enhanced pseudocapacitance behavior and exceptional power output capability of ZHCs.Furthermore,the reaction mechanism of physical and chemical adsorption/desorption of electrolyte ions on the P-CNT/rGO cathode is revealed by systematic ex-situ characterizations.This work can provide a valuable reference for developing advanced graphene-based cathode for high energy/power density ZHCs.

关键词： Graphene aerogel Phosphorus doping Pseudocapacitance Zinc-ion hybrid capacitors Energy storage mechanism

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Reversibly sensitizing-storing-releasing ^(1)O_(2) within a single platinum(Ⅱ)-acetylide-based metallacycle molecule via laser power modulation

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Science China Chemistry 2024年第2期67卷 604-611页

作者： ruyi Zhou Wen Lv Bo Li Bo Yu Sudi Zhang Yucheng Zhou Shujuan liu Qiang Zhao State Key Laboratory of Organic Electronics and Information Displays&Jiangsu Key Laboratory for Biosensors Institute of Advanced Materials(IAM)&Institute of Flexible Electronics(Future Technology)Nanjing University of Posts and Telecommunications(NUPT)Nanjing210023China College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology) Jiangsu Province Engineering Research Center for Fabrication and Application of Special Optical Fiber Materials and DevicesNanjing University of Posts and Telecommunications(NUPT)Nanjing210023China

Tumor hypoxia severely limits the therapeutic efficacy of photodynamic therapy(PDT) for solid tumors,which is highly dependent on tissue oxygen concentration.In this study,we developed a platinum(Ⅱ)-acetylide-based metallacycle compound bearing six 1,4-dimethylnaphthalenes(DMN) groups,and controlled the photodynamic and photothermal effects of the compound by adjusting the power of 730 nm laser to achieve reversible sensitization,storage and release of 1~O_(2) within a single molecule.The compound formed nanoparticles by self-assembly and exhibited good water solubility and biocompatibility.Under laser irradiation,the strong spin-orbit coupling of platinum atoms in the metallacycle facilitated 1~O_(2) generation.The produced 1~O_(2) was captured by the DMN carriers and transported into the hypoxic tumor,where 1~O_(2) release was triggered owing to the good photothermal effect of the extended conjugation of the metallacycle.During therapy,the metallacycle serving as a photosensitizer,1~O_(2) carrier,and photothermal reagent,achieved the synergistic therapy of PDT/PTT,demonstrating the versatility of the metallacycle.This study proposes a new strategy to develop phototherapy agents that are suitable for hypoxic tumors.

关键词： metallacycles singlet oxygen endoperoxides near-infrared absorption synergistic treatment

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Continuous-Time Mean-Variance Portfolio Selection Under Non-Markovian Regime-Switching Model with Random Horizon

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Journal of Systems Science & Complexity 2023年第2期36卷 457-479页

作者： CHEN Tian liu ruyi WU Zhen Zhongtai Securities Institute for Financial Studies Shandong UniversityJinan 250100China School of Mathematics and Statistics University of SydneyNSW 2006Australia School of Mathematics Shandong UniversityJinan 250100China

This paper considers a continuous-time mean-variance portfolio selection with regime-switching and random horizon.Unlike previous works,the dynamic of assets are described by non-Markovian regime-switching models in the sense that all the market parameters are predictable with respect to the filtration generated jointly by Markov chain and Brownian motion.The Markov chain is assumed to be independent of Brownian motion,thus the market is incomplete.The authors formulate this problem as a constrained stochastic linear-quadratic optimal control problem.The authors derive closed-form expressions for both the optimal portfolios and the efficient frontier.All the results are different from those in the problem with fixed time horizon.

关键词： Backward stochastic differential equation mean-variance portfolio selection random time horizon stochastic LQ control

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Phosphorylation of PB2 at serine 181 restricts viral replication and virulence of the highly pathogenic H5N1 avian influenza virus in mice

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Virologica Sinica 2024年第1期39卷 97-112页

作者： Jiao Hu Zixiong Zeng Xia Chen Manyu Zhang Zenglei Hu Min Gu Xiaoquan Wang ruyi Gao Shunlin Hu Yu Chen Xiaowen liu Daxin Peng Xiufan liu Animal Infectious Disease Laboratory School of Veterinary MedicineYangzhou UniversityYangzhou225009China Joint International Research Laboratory of Agriculture and Agri-Product Safety The Ministry of Education of ChinaYangzhou University225009China Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis Yangzhou UniversityYangzhou225009China Key Laboratory of Prevention and Control of Biological Hazard Factors(Animal Origin)for Agri-food Safety and Quality Ministry of Agriculture of China(26116120)Yangzhou UniversityYangzhou225009China

Influenza A virus(IAV)continues to pose a pandemic threat to public health,resulting a high mortality rate annually and during pandemic years.Posttranslational modification of viral protein plays a substantial role in regulating IAV infection.Here,based on immunoprecipitation(IP)-based mass spectrometry(MS)and purified virus-coupled MS,a total of 89 phosphorylation sites distributed among 10 encoded viral proteins of IAV were identified,including 60 novel phosphorylation sites.Additionally,for the first time,we provide evidence that PB2 can also be acetylated at site K187.Notably,the PB2 S181 phosphorylation site was consistently identified in both IP-based MS and purified virus-based MS.Both S181 and K187 are exposed on the surface of the PB2 protein and are highly conserved in various IAV strains,suggesting their fundamental importance in the IAV life cycle.Bioinformatic analysis results demonstrated that S181E/A and K187Q/R mimic mutations do not significantly alter the PB2 protein structure.While continuous phosphorylation mimicked by the PB2 S181E mutation substantially decreases viral fitness in mice,PB2 K187Q mimetic acetylation slightly enhances viral virulence in mice.Mechanistically,PB2 S181E substantially impairs viral polymerase activity and viral replication,remarkably dampens protein stability and nuclear accumulation of PB2,and significantly weakens IAV-induced inflammatory responses.Therefore,our study further enriches the database of phosphorylation and acetylation sites of influenza viral proteins,laying a foundation for subsequent mechanistic studies.Meanwhile,the unraveled antiviral effect of PB2 S181E mimetic phosphorylation may provide a new target for the subsequent study of antiviral drugs.

关键词： H5N1 influenza virus PB2 Phosphorylation Acetylation Viral fitness Mice

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Well-Posedness of Fully Coupled Linear Forward-Backward Stochastic Differential Equations

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Journal of Systems Science & Complexity 2019年第3期32卷 789-802页

作者： liu ruyi WU Zhen School of Mathematics and Zhongtai Securities Institute for Financial Studies Shandong University

This paper studies the well-posedness of fully coupled linear forward-backward stochastic differential equations (FBSDEs). The authors introduce two main methods-the method of continuation under monotonicity conditions and the unified approach-to ensure the existence and uniqueness of solutions of fully coupled linear FBSDEs. The authors show that the first method (the method of continuation under monotonicity conditions) can be deduced as a special case of the second method (the unified approach). An example is given to illustrate it in linear FBSDEs case. And then, a linear transformation method in virtue of the non-degeneracy of transformation matrix is introduced for cases that the linear FBSDEs can not be dealt with by the the method of continuation under monotonicity conditions and the unified approach directly. As a powerful supplement to the the method of continuation under monotonicity conditions and the unified approach, linear transformation method overall develops the well-posedness theory of fully coupled linear forward-backward stochastic differential equations which have potential applications in optimal control and partial differential equation theory.

关键词： Forward-backward stochastic differential equations linear transformation monotonicity conditions optimal control theory unified approach

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Pijx confers broad-spectrum seedling and panicle blast resistance by promoting the degradation of ATP b subunit and OsRbohC-mediated ROS burst in rice

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Molecular Plant 2024年第4期17卷 672-675页

作者： Ning Xiao Yunyu Wu Xiaoxiang Zhang Zeyun Hao Zichun Chen Zefeng Yang Yue Cai ruyi Wang Ling Yu Zhiping Wang Yue Lu Wei Shi Cunhong Pan Yuhong Li Changhai Zhou Jianju liu Niansheng Huang Guangqing liu Hongjuan Ji Shuhao Zhu Shuai Fang Yuese Ning Aihong Li 不详

(Molecular Plant 16,1832-1846,November 62023)The originally published version of this manuscript contained several small mistakes in the labels and legends of main and supplemental figures,along with a few small mistakes in the main text,that have now been corrected.Specifically,in Figure 6G,the label“NILGY31^(Pijx)”has been corrected to“NIL^(Pijx)”,and in the legend of Figure 6H,“PPL^(Pijx Piz-t)”and“PPL^(Pijx Pigm)”have been corrected to“NIL^(Piz-t Pijx)”and“PPL^(Pigm Pijx).”In Figure S8A。

关键词： seedling Figure panicle

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Effectiveness and safety of acupuncture in treatment of pregnancyrelated symptoms:a systematic review and Meta-analysis

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Journal of Traditional Chinese Medicine 2024年第1期44卷 16-26页

作者： liu Tingting liu Tongou liu Mingfu School of Traditional Chinese Medicine Clinical Medicine Hubei University of Traditional Chinese MedicineWuhan 430000China First Clinical College of Hubei University of Traditional Chinese Medicine Wuhan 430000China Department of Acupuncture and Tuina Affiliated Hospital of Hubei University of Traditional Chinese MedicineHubei Provincial Hospital of Traditional Chinese MedicineWuhan 430000China

OBJECTIVE:To systematically evaluate the efficacy and safety of acupuncture(AM)in the treatment of pregnancyrelated symptoms such as acute vomiting during pregnancy.METHODS:We comprehensively searched the available literature up to November 2021,including Pub Med,Embase,Cochrane Library,Chinese Biomedical Literature Database,and China National Knowledge Infrastructure Database,for randomized controlled trials(RCTs)on AM for the treatment of severe vomiting,insomnia,pharyngeal and pelvic pain,mood abnormalities,and dyspepsia during pregnancy.RESULTS:Sixteen RCTs with a cumulative sample size of 1178 cases were included.Of these,964 patients were included in the Meta-analysis.The Meta-analysis results showed that AM was more efficient than Western medicine in treating discomfort during pregnancy[odds ratio(OR)=1.19,95%confidence interval(CI)(1.11,1.28),P<0.01].AM was better than the control group in improving the visual analog scale scores[standard mean difference(SMD)=0.62,95%CI(0.53,0.71),P<0.01].AM was superior to the control group in improving Numerical Rating Scale(NRS)symptom scores[OR=7.31,95%CI(3.36,15.94),P<0.01].There was no significant difference in adverse effects between the AM and sham-AM groups and the analgesic drug group[OR=0.70,95%CI(0.39,1.28),P=0.25],but the treatment and control groups had mild adverse effects with a low incidence.CONCLUSIONS:AM is more effective than other treatments or pharmacotherapy alone in the treatment of pregnancy-related symptoms,and is relatively safe.However,the quality of the included trials was rather poor,and high-quality studies are required to confirm our findings.

关键词： acupuncture pregnancy nausea vomiting sleep initiation and maintenance disorders low back pain pelvic pain mood abnormalities Meta-analysis systematic review

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Removal of Cr(Ⅵ)by glutaraldehyde-crosslinked chitosan encapsulating microscale zero-valent iron:Synthesis,mechanism,and longevity

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Journal of Environmental Sciences 2024年第8期142卷 115-128页

作者： Yijun Duan Fang liu Xiang liu Miao Li School of Environment Tsinghua UniversityBeijing 100084China Transportation Institute of Inner Mongolia University Hohhot 010070China

Microscale zero-valent iron(mZVI)has shown great potential for groundwater Cr(Ⅵ)remediation.However,low Cr(Ⅵ)removal capacity caused by passivation restricted the wide use of mZVI.We prepared mZVI/GCS by encapsulating mZVI in a porous glutaraldehydecrosslinked chitosan matrix,and the formation of the passivation layer was alleviated by reducing the contact between zero-valent iron particles.The average pore diameter of mZVI/GCS was 8.775 nm,which confirmed the mesoporous characteristic of this material.Results of batch experiments demonstrated that mZVI/GCS exhibited high Cr(Ⅵ)removal efficiency in a wide range of pH(2-10)and temperature(5-35℃).Common groundwater coexisting ions slightly affected m ZVI/GCS.The material showed great reusability,and the average Cr(Ⅵ)removal efficiency was 90.41%during eight cycles.In this study,we also conducted kinetics and isotherms analysis.Pseudo-second-order model was the most matched kinetics model.The Cr(Ⅵ)adsorption process was fitted by both Langmuir and Freundlich isotherms models,and the maximum Langmuir adsorption capacity of m ZVI/GCS reached243.63 mg/g,which is higher than the adsorption capacities of materials reported in most of the previous studies.Notably,the column capacity for Cr(Ⅵ)removal of a mZVI/GCS-packed column was 6.4 times higher than that of a mZVI-packed column in a 50-day experiment.Therefore,mZVI/GCS with a porous structure effectively relieved passivation problems of mZVI and showed practical application prospects as groundwater Cr(Ⅵ)remediation material with practical application prospects.

关键词： Chitosan Glutaraldehyde mZVI Cr(Ⅵ) Groundwater

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Frequency Regulation of VSC-MTDC System with Offshore Wind Farms

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 275-286页

作者： Haoyu liu Chongru liu North China Electric Power University Beijing 102206China

Frequency regulation of voltage source converter-based multi-terminal high-voltage direct current(VSC-MTDC)system with offshore wind farms enhances the frequency stability by compensating the power for a disturbed AC system.However,it is difficult to reasonably allocate frequency-regulation resources due to a lack of coordination mechanisms between wind farms and the MTDC system.Moreover,it is difficult for the frequency control of the wind farms to manage changes in wind speed;and the risk of wind-turbine stalls is high.Thus,based on the kinetic energy of wind turbines and the power margin of the converters,the frequency-regulation capability of wind turbines is evaluated,and a dynamic frequency-support scheme considering the real-time frequency-support capability of the wind turbines and system frequency evolution is proposed to improve the frequency-support performance.A power adaptation technique at variable wind speeds is developed;the active power in the frequency-support stage and restoration stage is switched according to the wind speed.A hierarchical zoning frequency-regulation scheme is designed to use the frequency-regulation resources of different links in the MTDC system with wind farms.The simulation results show that the novel frequency-regulation strategy maintains frequency stability with wind-speed changes and avoids multiple frequency dips.

关键词： Wind generation voltage source converter-based multi-terminal high-voltage direct current(VSC-MTDC) frequency regulation cooperative control adaptive control variable wind speed

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