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Development and validation of a predictive model for the pathological upgrading of gastric low-grade intraepithelial neoplasia 被引量:2
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作者 Kun-Ming Lyu Qian-Qian Chen +4 位作者 Yi-Fan Xu Yao-Qian Yuan Jia-Feng Wang Jun Wan En-Qiang Ling-Hu 《World Journal of Gastroenterology》 2025年第11期63-73,共11页
BACKGROUND The discrepancy between endoscopic biopsy pathology and the overall pathology of gastric low-grade intraepithelial neoplasia(LGIN)presents challenges in developing diagnostic and treatment protocols.AIM To ... BACKGROUND The discrepancy between endoscopic biopsy pathology and the overall pathology of gastric low-grade intraepithelial neoplasia(LGIN)presents challenges in developing diagnostic and treatment protocols.AIM To develop a risk prediction model for the pathological upgrading of gastric LGIN to aid clinical diagnosis and treatment.METHODS We retrospectively analyzed data from patients newly diagnosed with gastric LGIN who underwent complete endoscopic resection within 6 months at the First Medical Center of Chinese People’s Liberation Army General Hospital between January 2008 and December 2023.A risk prediction model for the pathological progression of gastric LGIN was constructed and evaluated for accuracy and clinical applicability.RESULTS A total of 171 patients were included in this study:93 patients with high-grade intraepithelial neoplasia or early gastric cancer and 78 with LGIN.The logistic stepwise regression model demonstrated a sensitivity and specificity of 0.868 and 0.800,respectively,while the least absolute shrinkage and selection operator(LASSO)regression model showed sensitivity and specificity values of 0.842 and 0.840,respectively.The area under the curve(AUC)for the logistic model was 0.896,slightly lower than the AUC of 0.904 for the LASSO model.Internal validation with 30%of the data yielded AUC scores of 0.908 for the logistic model and 0.905 for the LASSO model.The LASSO model provided greater utility in clinical decision-making.CONCLUSION A risk prediction model for the pathological upgrading of gastric LGIN based on white-light and magnifying endoscopic features can accurately and effectively guide clinical diagnosis and treatment. 展开更多
关键词 Endoscopic resection Gastric low-grade intraepithelial neoplasia Early gastric cancer Pathological upgrade Prediction model
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Mechanism and Implementation Panths of Low-Altitude Economy in Promoting Transformation and Upgrading of Tourism Industry in Zhejiang Province
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作者 Zhenzi GUO 《Asian Agricultural Research》 2025年第8期13-15,26,共4页
Taking Zhejiang Province as an example,this paper explores the mechanisms and implementation pathways through which the low-altitude economy drives the transformation and upgrading of the tourism industry.It finds tha... Taking Zhejiang Province as an example,this paper explores the mechanisms and implementation pathways through which the low-altitude economy drives the transformation and upgrading of the tourism industry.It finds that the low-altitude economy can effectively promote the development of high-end and diversified tourism in Zhejiang by innovating tourism formats,optimizing resource allocation,and enhancing tourist experiences.Besides,it analyzes the current development status of the low-altitude economy in Zhejiang and its potential for integration with tourism,revealing specific enabling pathways for tourism transformation,including low-altitude sightseeing,aviation tourism,and low-altitude sports.Finally,it proposes policy recommendations such as strengthening policy support,enhancing infrastructure development,and cultivating market entities.The findings aim to provide theoretical references and practical guidance for the high-quality development of tourism in Zhejiang Province. 展开更多
关键词 LOW-ALTITUDE ECONOMY Transformation and upgrading of the tourism industry Action MECHANISM IMPLEMENTATION path ZHEJIANG Province
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Metallic cobalt mediated molybdenum nitride for efficient glycerol upgrading with water electrolysis
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作者 Yiming Guo Zhouhong Yu +1 位作者 Bin He Pengzuo Chen 《Chinese Chemical Letters》 2025年第9期589-594,共6页
Integrating electrochemical upgrading of glycerol and water electrolysis is regarded as a promising and energy-saving approach for the co-production of chemicals and hydrogen.However,developing efficient electrocataly... Integrating electrochemical upgrading of glycerol and water electrolysis is regarded as a promising and energy-saving approach for the co-production of chemicals and hydrogen.However,developing efficient electrocatalyst towards this technology remains challenging.Herein,a metallic cobalt mediated molybdenum nitride heterostructural material has been exploited on nickel foam(Co@Mo_(2)N/NF)for the glycerol oxidation reaction(GOR)and hydrogen evolution reaction(HER).Remarkably,the obtained Co@Mo_(2)N/NF realizes eminent performance with low overpotential of 49 mV at 50 mA/cm^(2)for HER and high Faradaic efficiency of formate of 95.03%at 1.35 V vs.RHE for GOR,respectively.The systematic in-situ experiments reveal that the Co@Mo_(2)N heterostructure promotes the cleavage of C-C bond in glycerol by active CoOOH species and boosts the conversion of glycerol to aldehyde intermediates to formate product.Moreover,the density functional theory(DFT)calculations confirm the strong interaction at Co@Mo_(2)N interface,which contributes to the optimized water dissociation and the transformation of H^(*)to H^(2).Benefiting from those advantages,the built HER||GOR electrolyzer delivers a low voltage of 1.61 V at 50 mA/cm^(2),high Faradaic efficiency,and robust stability over 120 h for sustained and stable electrolysis. 展开更多
关键词 Metallic Co Molybdenum nitride HETEROSTRUCTURE Glycerol upgrading Water electrolysis
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Rational design of oxygen vacancy-rich self-supporting NiCo(OH)_(2)electrode for efficient biomass upgrading
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作者 Diexin Xie Jiabin Chen +4 位作者 Jingxin Hou Fangfang Yang Runping Feng Changsheng Cao Zailai Xie 《Journal of Energy Chemistry》 2025年第9期558-566,I0015,共10页
Transition metal-based electrocatalysts are a promising alternative to noble metal catalysts for electrochemical upgrading of biomass-derived 5-hydroxymethylfurfural(HMF)into high-value 2,5-furandicarboxylic acid(FDCA... Transition metal-based electrocatalysts are a promising alternative to noble metal catalysts for electrochemical upgrading of biomass-derived 5-hydroxymethylfurfural(HMF)into high-value 2,5-furandicarboxylic acid(FDCA).However,the rational design of efficient electrocatalysts with precisely tailored structure-activity correlations remains a critical challenge.Herein,we report a hierarchically structured self-supporting electrode(Vo-NiCo(OH)_(2)-NF)synthesized through in situ electrochemical reconstruction of NiCo-Prussian blue analogue(NiCo-PBA)precursor,in which oxygen vacancy(Vo)-rich Co-doped Ni(OH)_(2)nanosheet arrays are vertically aligned on nickel foam(NF),creating an interconnected conductive network.When evaluated for the HMF oxidation reaction(HMFOR),Vo-NiCo(OH)_(2)-NF exhibits exceptional electrochemical performance,achieving near-complete HMF conversion(99%),ultrahigh FDCA Faradaic efficiency(97.5%),and remarkable product yield(96.2%)at 1.45 V,outperforming conventional Co-doped Ni(OH)_(2)(NiCo(OH)_(2)-NF)and pristine Ni(OH)_(2)(Ni(OH)_(2)-NF)electrodes.By combining in situ spectroscopic characterization and theoretical calculations,we elucidate that the synergistic effects of Co-doping and oxygen vacancy engineering effectively modulate the electronic structure of Ni active centers,favor the formation of high-valent Ni^(3+)species,and optimize HMF adsorption,thereby improving the HMFOR performance.This work provides valuable mechanistic insights for catalyst design and may inspire the development of advanced transition metal-based electrodes for efficient biomass conversion systems. 展开更多
关键词 Biomass upgrading Hierarchical structure Oxygen vacancy Transition metal-based electrodes ELECTROLYSIS
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Steering K/C dual sites to orient Lewis acid/oxygen species for photo-upgrading of biomass sugars into lactic acid
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作者 Qi-Zhi Luo Jin-Shu Huang +5 位作者 Teng-Yu Liu Ji-Li Yuan Artem S.Belousov Sheng-Kun Li Song Yang Hu Li 《Rare Metals》 2025年第5期3218-3233,共16页
Photocatalytic selective synthesis of lactic acid(LA)from biomass sugars with a single heterogeneous catalyst is promising but challenging due to the multiple reaction steps involved.Herein,a K-doped C-rich red polyme... Photocatalytic selective synthesis of lactic acid(LA)from biomass sugars with a single heterogeneous catalyst is promising but challenging due to the multiple reaction steps involved.Herein,a K-doped C-rich red polymerized carbon nitride(RPCN)photocatalyst with uniform K/C dual sites was constructed by a molten salt template method,which was highly efficient for cascade isomerization dehydration of glucose to LA with>90%selectivity under visible light and gentle conditions.Control experiments and theoretical calculations expounded that the introduced K/C dual sites could improve the light capture ability and photogenerated charge separation efficiency,while the K species provided sufficient Lewis acid sites(adsorption sites)for the isomerization of glucose to fructose.Meanwhile,the introduced C sites that substitute N atoms could promote electrons to be captured by adsorbed oxygen for selective generation of superoxide radicals,which was highly efficient for the scission of the C3-C4 bond in fructose,exclusively furnishing LA.Importantly,the RPCN photocatalyst was also suitable for the photocatalytic upgrading of various biomass saccharides into LA with high yields of 81.3%-95.3%and could be recycled for five consecutive cycles.The tailored construction of dual sites by localization of space charge lightens an avenue for multi-step conversion of biomass with pronounced selectivity. 展开更多
关键词 K-doped carbon nitride Biomass conversion Photocatalytic upgrading Lactic acid Tandem reaction
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Transcript of Central and Eastern European Agricultural Products Entering China:Steady Growth in Scale,Structural Upgrading and Potential
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作者 Qiu Liping Gu Wenbo 《China's Foreign Trade》 2025年第6期28-29,共2页
Agriculture is one of the core areas of economic development in Central and Eastern European countries(CEEC).Since the launch of the cooperation between China and Central and Eastern European countries(China-CEEC Coop... Agriculture is one of the core areas of economic development in Central and Eastern European countries(CEEC).Since the launch of the cooperation between China and Central and Eastern European countries(China-CEEC Cooperation)in 2012,agricultural trade has become a pillar of bilateral pragmatic cooperation.Expanding agricultural exports to China has always been the key demand of CEEC. 展开更多
关键词 agricultural exports economic development China CEEC cooperation structural upgrading central eastern european countries agricultural trade
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Sensation-thinking-simulacrum-construction:Upgrading path of sustainable design driven by modern artificial intelligence
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作者 GAO Yun-ting 《Ecological Economy》 2025年第4期380-400,共21页
Artificial intelligence(AI)is moving toward a new stage in its generalized development.To explain the upgrading path of sustainable design driven by AI can provide a certain basis and support for its application in de... Artificial intelligence(AI)is moving toward a new stage in its generalized development.To explain the upgrading path of sustainable design driven by AI can provide a certain basis and support for its application in design.Based on research into modern intelligence technology and design practices,this article(1)focuses on AI+,by means of relational comparisons and hierarchical structure analysis;(2)studies the value-added effect and new characteristics exhibited by the content,method,process,form,effect,and other aspects of design under the concept of sustainability;and(3)explores the upgrading mode and technological application of sustainable design,whose development is obviously influenced by the new generation of intelligence technology,through the upgrading paths of sensation,thinking,simulacrum,and construction.The continuous integration of sustainable design and AI is a trend that will endow the design process and designed objects with intelligent functions and multiple characteristics from the dimensions of cognition,thought,expression,and action.New tools and subjects will profoundly affect the value creation of design in the dimensions of environment,economy,and society. 展开更多
关键词 sustainable design artificial intelligence technology application upgrading
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Atomic vacancy engineering of Co(OH)F nanoarray toward high-performance ammonia electrosynthesis with waste plastics upgrading
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作者 Mingdan Wang Qianyu Zhang +4 位作者 Kun Chen Cong Lin Huigang Wang Yanying Zhao Pengzuo Chen 《Journal of Energy Chemistry》 2025年第10期558-565,共8页
Developing energy-efficient nitrite-to-ammonia(NO_(2)RR)conversion technologies while simultaneously enabling the electrochemical upcycling of waste polyethylene terephthalate(PET)plastics into highvalue-added chemica... Developing energy-efficient nitrite-to-ammonia(NO_(2)RR)conversion technologies while simultaneously enabling the electrochemical upcycling of waste polyethylene terephthalate(PET)plastics into highvalue-added chemicals is of great significance.Herein,an atomic oxygen vacancy(V_(o))engineering is developed to optimize the catalytic performance of V_(o2)-Co(OH)F nanoarray towards the NO_(2)RR and PET-derived ethylene glycol oxidation reaction(EGOR).The optimal V_(o2)-Co(OH)F achieves an ultralow operating potential of -0.03 V vs.RHE at -100 mA cm^(-2)and a remarkable NH_(3)Faradaic efficiency(FE)of 98.4% at -0.2 V vs.RHE for NO_(2)RR,and a high formate FE of 98.03% for EGOR.Operando spectroscopic analysis and theoretical calculations revealed that oxygen vacancies play a crucial role in optimizing the electronic structure of V_(o2)-Co(OH)F,modulating the adsorption free energies of key reaction intermediates,and lowering the reaction energy barrier,thereby enhancing its overall catalytic performance.Remarkably,the V_(o2)-Co(OH)F-based NO_(2)RR||EGOR electrolyzer realized high NH_(3)and formate yield rates of 33.9 and 44.9 mg h^(-1)cm^(-2)at 1.7 V,respectively,while demonstrating outstanding long-term stability over 100 h.This work provides valuable insights into the rational design of advanced electrocatalysts for co-electrolysis systems. 展开更多
关键词 Atomic vacancy Co(OH)F Nanoarray Ammonia electrosynthesis Waste plastics upgrading Co-electrolysis system
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Research on the Impact of Digital Economy on Industrial Structure Upgrading
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作者 Zetai Kong 《Proceedings of Business and Economic Studies》 2025年第2期274-280,共7页
With the swift advancement of the modern economy,the digital economy has progressively merged into various sectors.By leveraging cutting-edge information technology,it has become a pivotal strategy to enhance both pro... With the swift advancement of the modern economy,the digital economy has progressively merged into various sectors.By leveraging cutting-edge information technology,it has become a pivotal strategy to enhance both production efficiency and quality,representing the inevitable route for the transformation and upgrading of modern enterprises and industries.As the digital economy continues to develop and spread,technology has not only given rise to numerous new industries but also fostered a conducive environment for the transformation and upgrading of traditional sectors.This study takes this context as its research backdrop,examining the development background of the digital economy.It outlines the impact mechanisms through which the digital economy influences industrial structure upgrading and subsequently identifies the specific effects of the digital economy on such upgrades.Furthermore,it constructs a reform paradigm for the digital economy aimed at facilitating the upgrading of industrial structures. 展开更多
关键词 Digital economy Industrial structure Transformation and upgrading IMPACT
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Recent developments in the utilization of unconventional resources:A focus on partial upgrading techniques and sustainability of Canadian Oil sand bitumen
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作者 Moataz K.Abdrabou Xue Han +1 位作者 Yimin Zeng Ying Zheng 《Resources Chemicals and Materials》 2025年第1期88-109,共22页
To satisfy the increasing global energy demand,while searching for new energy sources,it’s important to take a closer look at the resources already at our disposal and optimize their use.This comprehensive review exp... To satisfy the increasing global energy demand,while searching for new energy sources,it’s important to take a closer look at the resources already at our disposal and optimize their use.This comprehensive review explores the evolving landscape of unconventional oil resources,focusing on the environmental and economic implica-tions of bitumen partial upgrading technologies,particularly within the Canadian context.With over 55%of the world’s oil reserves comprising of unconventional oil,which includes extra-heavy oil and oil sand bitumen,there is a growing trend to shift from traditional oil sources to these abundant yet under-utilized reserves.This review delves into the challenges and advancements in bitumen partial upgrading,highlighting the latest technologies in thermal cracking,hydrocracking,catalytic cracking,and innovative methods like surfactant integration,cavi-tation,microwave,and plasma-assisted upgrading.It also discusses the environmental implications and eco-nomic feasibility of these technologies,emphasizing the necessity for sustainable and cost-effective solutions at petroleum field sites.Furthermore,the report introduces the transformative concept of Bitumen Beyond Com-bustion(BBC),which explores the non-combustion uses of bitumen and its asphaltene fraction in manufacturing high-value carbon-based products.These novel approaches align with global sustainability goals,offering the potential for significant reductions in greenhouse gas emissions and new routes to diversify the economic ap-plications of bitumen.The review then concludes with an assessment of current challenges and future research directions,advocating for a balanced approach that harmonizes technological innovation,environmental stewardship,and economic viability in the field of bitumen upgrading. 展开更多
关键词 Bitumen upgrading Unconventional oil resources Environmental sustainability Advanced material production
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Research on the Impact of the Construction of Cross-border E-commerce Comprehensive Pilot Zones on China’s Export Transformation and Upgrading
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作者 Jiahui Zhao 《Proceedings of Business and Economic Studies》 2025年第6期45-52,共8页
Cross-border e-commerce has emerged as a new growth point in foreign trade.While the Dalian comprehensive pilot zone has made some progress,its development is constrained by issues such as the global economic slowdown... Cross-border e-commerce has emerged as a new growth point in foreign trade.While the Dalian comprehensive pilot zone has made some progress,its development is constrained by issues such as the global economic slowdown,the relatively small scale of cross-border e-commerce,a high concentration of export commodities,imperfect information mechanisms,and high overall costs.To address these challenges,this paper explores the importance of the construction of the Dalian comprehensive pilot zone for cross-border e-commerce to the transformation and upgrading of exports.Based on my research project,“Research on Path Optimization of Financial Support for the Development of Advanced Manufacturing Clusters in Dalian,”this paper analyzes the current challenges and limiting factors and proposes corresponding countermeasures and suggestions. 展开更多
关键词 Cross-border e-commerce comprehensive pilot zone Cross-border e-commerce Export transformation and upgrading Foreign trade export
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Research on the Impact Mechanism of Green Finance on the Optimization and Upgrading of Regional Industrial Structure
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作者 Zhiwei Pan 《Proceedings of Business and Economic Studies》 2025年第4期381-390,共10页
Under the background of this era,green finance and the upgrading and optimization of industrial structure have become a hot research topic.The article focuses on Jiangsu Province,carefully explores the impact of green... Under the background of this era,green finance and the upgrading and optimization of industrial structure have become a hot research topic.The article focuses on Jiangsu Province,carefully explores the impact of green financial development on the upgrading and optimization of industrial structure and the real effect,collates and summarizes the theories of green finance and industrial structure at home and abroad,and carefully analyzes the development of green finance in Jiangsu Province,such as the gradual expansion of green credit scale,the characteristics of industrial structure,the change of the proportion of three industries,the development situation of emerging industries and so on.By means of econometrics,an empirical model covering Green Financial Development Indicators and industrial structure optimization indicators is established to do multiple linear regression analysis and stability test.The empirical results show that the development of green finance in Jiangsu plays an obvious positive role in the optimization and upgrading of industrial structure.Green finance is environmental protection,new energy and other green industries are given important financial support,which drives their scale expansion and technological innovation,and makes the industrial structure develop towards a higher level and a more reasonable direction.From this point of view,corresponding proposals are put forward to improve the policy incentive system,add green financial products,and strengthen the construction of green financial market.The purpose is to give better play to the advantages of green finance,accelerate the optimization and upgrading of industrial structure in Jiangsu,and provide theoretical basis and practical guidance for achieving green economic transformation and sustainable development. 展开更多
关键词 Green finance Optimization and upgrading of industrial structure Entropy weight method Multiple linear regression model
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Impact of heterogeneity of sanitary and phytosanitary measures on the upgrading of agricultural global value chains
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作者 DONG Yin-guo YANG Zun-rong SHAN Zhan-yao 《Ecological Economy》 2025年第3期202-213,共12页
With the deepening of international agricultural division of labor,trade methods have shifted from traditional bilateral trade to agricultural global value chain(AGVC)trade.Sanitary and Phytosanitary(SPS)measures are ... With the deepening of international agricultural division of labor,trade methods have shifted from traditional bilateral trade to agricultural global value chain(AGVC)trade.Sanitary and Phytosanitary(SPS)measures are a crucial factor affecting agricultural trade and a key variable in AGVC governance.This paper,based on the 2012-2020 University of International Business and Economics Global Value Chain Index(UIBE GVC Index)and the United Nations Conference on Trade and Development Non-Tariff Measures Database(UNCTAD NTMs Database),measures the structural heterogeneity and breadth heterogeneity of SPS measures.It also constructs mathematical models and fixed-effects models to explore the impact of SPS heterogeneity on AGVC upgrading.The findings reveal that the heterogeneity of SPS measures exerts a significant inhibitory effect on the upgrading of agricultural global value chains.Moreover,compared to developed countries,a reduction in SPS measures’heterogeneity demonstrates a more pronounced positive impact on AGVC upgrading in developing countries. 展开更多
关键词 Sanitary and Phytosanitary measures heterogeneity agriculture domestic value added in exports agricultural global value chain upgrading
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ESG rating and transformation upgrading of enterprises:An empirical test based on the heterogeneity of listed A-share enterprises
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作者 WEI Yu-xin LI Peng-yu +1 位作者 LI Yan CHEN Xi-meng 《Ecological Economy》 2025年第1期48-65,共18页
ESG(Environmental,Social,and Governance)performance has emerged as a central metric in assessing corporate sustainability.Utilizing ESG rating data for A-share listed companies on the Shanghai Stock Exchange spanning ... ESG(Environmental,Social,and Governance)performance has emerged as a central metric in assessing corporate sustainability.Utilizing ESG rating data for A-share listed companies on the Shanghai Stock Exchange spanning from 2019 to 2022,coupled with measures of corporate transformation and upgrading,this study introduces green innovation as a mediating variable to dissect the impact of ESG ratings on corporate transformation and upgrading.The key findings of this research are as follows:(1)ESG ratings positively influence corporate transformation and upgrading,a conclusion that retains robustness after a comprehensive series of tests and discussions on endogeneity.(2)Mechanism analysis reveals that ESG ratings foster corporate transformation and upgrading by enhancing corporate green innovation.(3)In comparison with other industries,the influence of ESG ratings on corporate transformation and upgrading is notably more pronounced among heavily polluting industries among listed companies in China.Additionally,ESG ratings exhibit a more significant promotional effect on non-state-owned enterprises compared to state-owned enterprises.Larger enterprises play a more substantial role in transformation and upgrading than small and medium-sized enterprises.The promotional effect of ESG ratings is more evident in enterprises with poor information disclosure quality.Furthermore,as media attention increases,so does the impact of ESG ratings on corporate transformation.This study offers valuable policy insights from the ESG rating perspective,aiming to propel corporate transformation and upgrading,thereby contributing to economic high-quality and sustainable development. 展开更多
关键词 ESG rating enterprise transformation and upgrading heterogeneity analysis
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我国芹菜育苗机械化装备与技术研究进展 被引量:3
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作者 曹玲玲 曹彩红 +1 位作者 姜凯 张骞 《农机化研究》 北大核心 2026年第1期277-285,共9页
系统分析了我国芹菜育苗机械化装备与技术的研究进展、现存问题及发展趋势。当前我国芹菜种植已形成覆盖全国的生产网络与完整产业链,但育苗环节仍以传统人工操作为主,存在劳动强度大、效率低等突出问题,制约了芹菜产业规模化发展。尽... 系统分析了我国芹菜育苗机械化装备与技术的研究进展、现存问题及发展趋势。当前我国芹菜种植已形成覆盖全国的生产网络与完整产业链,但育苗环节仍以传统人工操作为主,存在劳动强度大、效率低等突出问题,制约了芹菜产业规模化发展。尽管种子处理、穴盘播种、环境调控及育苗移栽等环节已研发出系列机械化装备,其应用显著提升了生产标准化水平,但核心技术自主创新能力不足,高精度传感、智能控制等关键领域依赖进口,导致装备成本高且创新受限;同时,装备性能与农艺需求适配性不足,播种移栽合格率低、幼苗损伤及极端环境调控滞后等问题突出,加之农艺与机械跨学科协作薄弱、装备全生命周期成本高及复合型人才短缺,进一步阻碍产业升级。未来,芹菜育苗机械化将聚焦智能化集成、绿色可持续发展及产学研深度融合,通过智能技术实现育苗环境与作业流程的精准调控,推广清洁能源与环保材料应用,强化政府、科研机构与企业的协同创新,构建高效、可持续的机械化体系,为蔬菜产业高质量发展提供技术支撑。 展开更多
关键词 芹菜 育苗 机械化装备 产业升级
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产品质量升级一定能提升出口企业成本加成吗?
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作者 刘晓宁 《国际商务研究》 北大核心 2026年第1期59-71,共13页
本文基于中国工业企业和海关数据,研究了出口产品质量升级对企业成本加成的差异化影响效应,从加成率角度考察出口企业产品质量升级行为的贸易利得。研究发现,短期内产品质量对出口企业成本加成率呈现倒U型影响,即先表现出“质量升级红利... 本文基于中国工业企业和海关数据,研究了出口产品质量升级对企业成本加成的差异化影响效应,从加成率角度考察出口企业产品质量升级行为的贸易利得。研究发现,短期内产品质量对出口企业成本加成率呈现倒U型影响,即先表现出“质量升级红利”,而后陷入“质量升级陷阱”;长期看,“质量升级陷阱”趋于消失。其中,私营出口企业可以完全享受“质量升级红利”,而劳动密集型企业更易陷入“质量升级陷阱”。从影响机制看,随着产品质量的提升,企业出口产品价格也随之提升,企业生产的边际成本随之增加,企业成本加成率的最终变化方向取决于“价格提升效应”和“成本增加效应”的对比。 展开更多
关键词 出口企业 产品质量 成本加成率 质量升级红利 质量升级陷阱
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城市物流标准化效率的空间差异及与产业结构升级的交互溢出效应
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作者 张宝友 郭鹏丽 +1 位作者 孟丽君 徐茜 《地理科学》 北大核心 2026年第2期451-464,共14页
本文通过评估2006—2022年中国284个城市的物流标准化效率,重点考察了区域差异及其来源与动态分布演化特征,并采用空间联立方程模型对城市的物流标准化效率与物流产业结构升级之间的空间溢出效应进行探究。研究发现:(1)全国总体及东部... 本文通过评估2006—2022年中国284个城市的物流标准化效率,重点考察了区域差异及其来源与动态分布演化特征,并采用空间联立方程模型对城市的物流标准化效率与物流产业结构升级之间的空间溢出效应进行探究。研究发现:(1)全国总体及东部、中部与西部3个区域的城市物流标准化效率逐年提升,但区域之间的绝对差距不断扩大;(2)全国总体差异以年平均增幅5.48%的速度不断扩大,造成总体差异的主要来源是区域间差异与超密度。中部和西部区域内的差异高于东部区域,东部-中部、东部-西部之间的差异大于中部-西部地区。(3)中国城市物流标准化效率与其产业结构升级之间存在正向交互效应,互促关系中城市产业结构升级处于相对优势地位,且二者在地理空间上均存在显著的空间溢出效应及空间交互影响效应。 展开更多
关键词 城市物流标准化效率 产业结构升级 交互溢出效应
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基于全球价值链的环境升级研究进展和启示
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作者 沈静 刘羿滢 魏成 《地理科学进展》 北大核心 2026年第1期1-12,共12页
随着全球生态风险加剧,环境升级已经成为全球价值链研究的重要议题。基于全球价值链的环境升级研究关注经济行动者在不同环节进行环境治理的机制和路径,强调环境价值转化为经济价值的可能性。论文回顾国外基于全球价值链的环境升级概念... 随着全球生态风险加剧,环境升级已经成为全球价值链研究的重要议题。基于全球价值链的环境升级研究关注经济行动者在不同环节进行环境治理的机制和路径,强调环境价值转化为经济价值的可能性。论文回顾国外基于全球价值链的环境升级概念与研究进展,梳理环境升级的驱动机制、实践方式、治理结构和作用结果,分析环境升级研究所体现的空间维度,得到以下主要结论:(1)环境升级由全球价值链内外多主体共同驱动;(2)环境升级方式依据经济升级过程进行划分和拓展,呈现多元化的策略和措施;(3)环境升级的治理结构存在自上而下和自下而上的垂直治理以及水平治理三种类型,揭示不同主体之间的互动规则和权力动态;(4)环境升级在环境、经济和社会三个维度对价值链行动者及其所处区域产生差异化影响;(5)基于全球价值链的环境升级过程具有显著的地理空间特性,体现了多尺度的空间互动关系和区域差异特征。目前国内研究尚处于起步阶段,未来应当融合全球视野和地方经验,从全球、国家和地方等不同尺度来剖析环境升级机制,重新思考环境和经济的关系问题。 展开更多
关键词 环境升级 全球价值链 环境治理 产业路径
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地方院校智能建造专业课程体系建设和案例探讨
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作者 门进杰 田卫 +2 位作者 徐亚洲 王军保 谷坤文 《高等建筑教育》 2026年第1期98-105,共8页
智能建造正逐步成为推动建筑业转型升级的关键力量。近年来,智能建造技术在全球范围内发展迅速,并得到了广泛应用。为了满足行业对智能建造人才培养的需求,我国开设智能建造专业的高校快速增多,同时诸如课程体系建设等方面的问题也更加... 智能建造正逐步成为推动建筑业转型升级的关键力量。近年来,智能建造技术在全球范围内发展迅速,并得到了广泛应用。为了满足行业对智能建造人才培养的需求,我国开设智能建造专业的高校快速增多,同时诸如课程体系建设等方面的问题也更加凸显。文章介绍了智能建造专业人才培养目标定位和课程体系总体构建思路,在研究分析了专业课程体系建设七大方面的基础上,提出了课程体系建设的架构,并以3门理论课程、1门实践课程为例,探讨了智能建造课程的转型升级情况,为相关高校智能建造专业的建设提供参考。 展开更多
关键词 智能建造 课程体系 课程案例 转型升级
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2ZPY-H530型水稻钵苗行栽机造型升级
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作者 张云文 刘凯 +3 位作者 徐毓蔚 刘彩玲 何凤珠 马荣华 《农机化研究》 北大核心 2026年第5期175-182,300,共9页
现有的农业机械产品主要侧重功能实现与成本控制,不重视外观造型与人的因素,影响产品的操作体验、作业安全和市场竞争力。为此,基于工业设计学科理论,以2ZPY-H530型水稻钵苗行栽机原型机为研究对象,基于对功能结构组成和存在问题的分析... 现有的农业机械产品主要侧重功能实现与成本控制,不重视外观造型与人的因素,影响产品的操作体验、作业安全和市场竞争力。为此,基于工业设计学科理论,以2ZPY-H530型水稻钵苗行栽机原型机为研究对象,基于对功能结构组成和存在问题的分析,确定了以优化操作体验、提高安全性和提升整机造型美感为设计目标,改进了驾驶座设计和喂入手作业空间布局,优化了驾驶员操作界面和操作杆形态,对牵引部分的挡泥板、辅助踏板和行栽机主体的输秧装置、秧盘架和接秧盘筐等部件进行了改进设计;结合农业机械的人-机-环境系统理论,应用AHP-TOPSIS法开展了色彩设计研究,基于用户色彩感性需求构建了层次结构模型用于评价色彩设计方案;采用参数化设计方法进行了整机建模,输出了设计方案效果图,旨在为农业机械外观设计提供参考范例。 展开更多
关键词 水稻钵苗行栽机 工业设计 造型升级 AHP-TOPSIS法 色彩设计
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