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Journal of Applied Mathematics and Physics 2024年第9期12卷 3066-3080页

作者： Simin Wu Yan Liang Weixun Li School of Sciences Guangdong University of Petrochemical Technology Maoming China School of Quantitative Sciences Universiti Utara Malaysia Kedah Malaysia

This study utilizes the Dynamic Conditional Correlation-Generalized Autoregressive Conditional Heteroskedasticity (DCC-GARCH) model to investigate the dynamic relationship between Chinese and U.S. stock markets amid the COVID-19 pandemic. Initially, a univariate GARCH model is developed to derive residual sequences, which are then used to estimate the DCC model parameters. The research reveals a significant rise in the interconnection between the Chinese and U.S. stock markets during the pandemic. The S&P 500 index displayed higher sensitivity and greater volatility in response to the pandemic, whereas the CSI 300 index showed superior resilience and stability. Analysis and model estimation suggest that the market’s dependence on historical data has intensified and its sensitivity to recent shocks has heightened. Predictions from the model indicate increased market volatility during the pandemic. While the model is proficient in capturing market trends, there remains potential for enhancing the accuracy of specific volatility predictions. The study proposes recommendations for policymakers and investors, highlighting the importance of improved cooperation in international financial market regulation and investor education.

关键词： DCC-GARCH Model Stock market Linkage COVID-19 market Volatility Forecasting Analysis

Impact of Shipping Distance on Online Retailers' Sales:A Case Study of Maiyang on Tmall

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Chinese Geographical Science 2018年第2期28卷 261-273页

作者： ZHOU Chunshan JIN Wanfu ZHANG Guojun School of Geography and Planning Sun Yat-sen University School of Public administration Guangdong University of Finance and Economics

Many studies have qualitatively explained that information and communication technology(ICT) has loosened the restrictions of distance and space on retailers' sales. Few empirical studies, however, have explored the impact of shipping distance on online retailers' sales. This study examined the Maiyang(M-Y) store on Tmall in China as a case study to investigate the relationship between shipping distance and sales. The results showed that sales volume in 2014 at the county level did not strictly obey the distance decay law. The shipped distance of high-priced commodities may not be much longer than that of low-priced commodities. Within the scope of investigation, the relationships between income, cost, and net profit curves do not follow central place theory. Goods have neither thresholds nor ranges. The key factor in the spatial discrepancy of sales is the size of market. The impact of shipping distance on sales is not as strong as that of traditional retailers in Information Era.

关键词： online retailers shipping distance central place theory

Voluntary CSR disclosure, institutional environment,and independent audit demand

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China Journal of Accounting Research 2019年第4期12卷 357-377页

作者： Peipei Zheng Chunyan Ren School of Accounting/Institute of Capital market and Audit Governance Studies for the Great Bay Area(guangdong Hong KongMacao)Guangdong University of Finance and EconomicsChina School of Management Xiamen UniversityChina

Using a sample of A-share listed companies on the Shanghai and Shenzhen Stock Exchanges,this study examines the impact of voluntary corporate social responsibility(CSR)disclosure on independent audit demand in different institutional *** sample covers the 2008–2016 period and excludes firms that are required to disclose CSR *** findings show that compared with companies that choose to not disclose such information,companies that voluntarily disclose CSR information prefer to employ‘‘small"accounting firms for auditing services,although the auditing fees are much ***,as the institutional environment improves,this preference is *** analyses show that this preference is stronger in enterprises where CSR disclosure is driven by strong political motivations and managerial self-interest *** motivations and economic motivations do not significantly impact the preference for‘‘small"audit ***,this preference is more obvious in enterprises with poor operational performance and low information disclosure quality,and it increases as CSR disclosure level *** study enriches our understanding of the economic consequences of voluntary CSR disclosure and the factors that influence independent audit *** results also have implications for the construction and regulation of China’s system for supervising CSR information disclosure in the transitional phase.

关键词： Voluntary disclosure of corporate social responsibility information Auditor selection Auditing fees Institutional environment

H_(2)O_(2)mediates transcriptome reprogramming during Soybean mosaic virus-induced callose deposition in soybean

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The Crop Journal 2022年第1期10卷 262-272页

作者： Tianjie Sun Xizhe Sun Fukuan Li Nan Ma Mengxuan Wang Yan Chen Na Liu Yuan Jin Jie Zhang Chunyan Hou Chunyan Yang Dongmei Wang State Key Laboratory of North China Crop Improvement and regulation Baoding 071000HebeiChina Key Laboratory of Hebei Province for Plant Physiology and Molecular Pathology Baoding 071000HebeiChina College of Life Sciences Hebei Agricultural UniversityBaoding 071000HebeiChina market Supervision administration of Chongli District Zhangjiakou 076350HebeiChina Institute of Cereal and Oil Crops Hebei Academy of Agriculture and Forestry SciencesShijiazhuang 050035HebeiChina

The main defense response to Soybean mosaic virus(SMV)infection in soybean[Glycine max(L.)Merr.]is thought to be blockage of intercellular virus transport by callose deposition on *** the specific regulatory mechanism remains largely *** this study,we found that hydrogen peroxide(H_(2)O_(2))signal downstream of NO was associated with the regulation of callose *** H_(2)O_(2)was produced on the cell membrane and cell wall in the incompatible combination of soybean cultivar Jidou 7 and SMV strain N3,whereas no obvious H_(2)O_(2)was observed in the compatible combination of Jidou 7 and strain *** H_(2)O_(2)production was inhibited,callose accumulation induced by SMV infection decreased to a level insufficient to restrict virus transport in the incompatible *** H_(2)O_(2)-associated transcriptome dynamics of soybean during SMV infection was *** and functional analysis using virus-induced gene silencing showed that Gm SEOB and Gm PAP27,two genes regulated by H_(2)O_(2),functioned in resistance by positively regulating the accumulation of callose in response to SMV *** results lay a foundation for further research on the signal transduction and molecular regulation of callose deposition during soybean resistance to SMV infection.

关键词： Callose Soybean mosaic virus H_(2)O_(2) Transcriptome Soybean

Space diversification process and evolution mechanism of typical village in the suburbs of Guangzhou:A case study of Beicun

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Journal of Geographical Sciences 2020年第7期30卷 1155-1178页

作者： YANG Ren PAN Yuxin XU Qian School of Geography and Planning Sun Yat-sen UniversityGuangzhou 510275China School of Public administration Guangdong University of Finance&EconomicsGuangzhou 510320China

The reform of global production mode and social system accelerate the process of urbanization,and the urban-rural factors accelerate rural space *** on the space production theory and game theory,this paper analyzed the space diversification process and its influence on Beicun *** results show that:(1)In the past 30 years,the development of Beicun has experienced three stages:agricultural development,industrial development,and service industrial *** industrial structure has changed from single to *** transformation of agricultural decentralization to rural community has been realized.(2)Accompanying the rural economic development transformation,the land use type and structure of Beicun has *** spatial relationship of various types of land use was complicated and gave rise to new characteristics of mixed land for commercial and residential use,and industrial and commercial use,gradually forming a circular spatial layout structure model of public service facilities,traditional residential areas and modern residential areas,commercial areas,agricultural and industrial areas.(3)Rural space diversification was mainly due to the intervention of new industries and the transformation of leading *** endogenous land transferring mechanism and exogenous urban capital jointly promoted the industrialization process,and the market power promoted the transformation of industry into the service industry.(4)The industrialization process promoted the functional replacement of historical buildings by village *** changed the social relations of the village with the blood clan and geography oriented,and produced the occupational relation between migrant workers and urban low-income groups.(5)The multi-differentiation of suburban rural space followed the game logic of capital and land *** rural community played a key mediation in the competition for space and the game of interests among local vill

关键词： rural development space differentiation space production game theory Beicun village

RBMDO Using Gaussian Mixture Model-Based Second-Order Mean-Value Saddlepoint Approximation

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Computer Modeling in Engineering & Sciences 2022年第8期132卷 553-568页

作者： Debiao Meng Shiyuan Yang Tao Lin Jiapeng Wang Hengfei Yang Zhiyuan Lv School of Mechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengdu611731China Failure Mechanics&Engineering Disaster Prevention and Mitigation Key Laboratory of Sichuan ProvinceSichuan UniversityChengdu610065China Yangzhou Yangjie Electronic Technology Co. Ltd.Yangzhou225008China Sichuan Special Equipment Inspection and Research Institute Chengdu610100China Food Safety Inspection Technology Center of administration for market regulation of Sichuan Province Chengdu610017China

Actual engineering systems will be inevitably affected by uncertain ***,the Reliability-Based Multidisciplinary Design Optimization(RBMDO)has become a hotspot for recent research and application in complex engineering system *** Second-Order/First-Order Mean-Value Saddlepoint Approximate(SOMVSA/-FOMVSA)are two popular reliability analysis strategies that are widely used in ***,the SOMVSA method can only be used efficiently when the distribution of input variables is Gaussian distribution,which significantly limits its *** this study,the Gaussian Mixture Model-based Second-Order Mean-Value Saddlepoint Approximation(GMM-SOMVSA)is introduced to tackle above *** is integrated with the Collaborative Optimization(CO)method to solve RBMDO ***,the formula and procedure of RBMDO using GMM-SOMVSA-Based CO(GMM-SOMVSA-CO)are ***,an engineering example is given to show the application of the GMM-SOMVSA-CO method.

关键词： Uncertain factors reliability-based multidisciplinary design optimization saddlepoint approximate gaussian mixture model collaborative optimization

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单细胞转录组测序技术畜牧业标准化现状分析

China Standardization 2023年第1期119卷 60-64页

作者：李夏伟张琦朱晓春王斌 Inner Mongolia Institute of Quality and Standardization Inner Mongolia Administration for Market Regulation

Single-cell RNA sequencing technology(scRNA-seq)is an emerging,high-throughput,high-resolution big data production and analysis technology,which has helped some pioneering research and discoveries in the field of animal husbandry in recent *** technology provides an essential basis for the early selection of livestock and poultry and the selection of excellent characters,showing that it has great application potential and broad prospects in animal husbandry research and *** scRNA-seq technology has established a wide range of commercial production services at home and abroad,the standardization status of this technology in animal husbandry needs further exploration,as it can provide clues and foundations for the application of scRNA-seq technology in animal husbandry.

关键词： single-cell RNA sequencing technology animal husbandry standardization genetic breeding

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Exploring the Evolutionary Path of Digital Financial Inclusion in guangdong Province,China

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Proceedings of Business and Economic Studies 2024年第1期7卷 16-26页

作者： Juan Zhang School of Information Management and Engineering Neusoft Institute GuangdongFoshan 528000Guangdong ProvinceChina

This study explores the development trajectory of digital financial inclusion in 21 cities in guangdong Province through fuzzy-set qualitative comparative analysis(fsQCA).The findings emphasize that the success of digital financial inclusion goes beyond individual dimensions,forming a systematic initiative marked by multifaceted interaction among different *** the trajectory of high-level digital inclusive finance development,the study identifies economic prosperity and technological innovation as crucial elements,highlighting their centrality,and elucidates the synergistic collaboration between market mechanisms and government ***,the study emphasizes the government’s pivotal role in supporting market mechanisms and guiding policies,highlighting the need to achieve a nuanced equilibrium in the digital financial inclusion *** contrast,non-high-level development paths of digital inclusive finance show a spectrum of diversities,emphasizing the critical roles played by economic fundamentals,government regulation,market mechanisms,and other contextual factors in different *** policy implications,the study emphasizes the comprehensive and systemic nature inherent in the development of digital inclusive *** proposes four policy recommendations,including integrating development strategies,emphasizing scientific and technological innovation and economic development,achieving a delicate balance between market mechanisms and government guidance,and providing precise policy *** insights provide valuable lessons for shaping digital inclusive financial policies in guangdong Province and beyond,offering profound insights for strategically constructing robust digital financial ecosystems.

关键词： Digital inclusive finance Impact pathways Economic development level Technological innovation Fuzzy-set qualitative comparative analysis(fsQCA)

Determination of egg and milk allergen in food products by liquid chromatography-tandem mass spectrometry based on signature peptides and isotope-labeled internal standard

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Food Science and Human Wellness 2023年第3期12卷 728-736页

作者： Sufang Fan Junmei Ma Zhuo Liu Yawei Ning Meicong Cao Qiang Li Yan Zhang Hebei Food Safety Key Laboratory Key Laboratory of Special Food Supervision Technology for State Market RegulationHebei Engineering Research Center for Special Food Safety and HealthHebei Food Inspection and Research InstituteShijiazhuang 050227China College of Bioscience and Bioengineering Hebei University of Science and TechnologyShijiazhuang 050018China

The aim of this work was to develop a liquid chromatography-tandem mass spectrometry method for the determination of milk allergen and egg allergen in food *** peptides GGLEPINFQTAADQAR,VGINYWLAHK,VLVLDTDYK,FFVAPFPEVFGK,and NAVPITPTLNR were confirmed and synthesized as the quantitative peptide of ovalbumin,α-lactalbumin,β-lactoglobulin,α_(S1)-casein andα_(S2)-casein,the relative isotope-labeled internal standards were used in the quantitative *** range was in the range of0.5-5000.0 nmol/L for egg and milk allergen in bread,cake,cookie,rice crust and wheat flour samples with free from egg and milk,the limits of detection of milk allergens and egg allergen were in the range between0.94 mg/100 g and 56.71 mg/100 g,limits of quantification of milk allergens and egg allergen were in the range between 2.36 mg/100 g and 141.78 mg/100 *** recoveries ranged from 76.7%to 122.8%,the relative standard deviations were in the range of 1.60%-15.60%.The developed method has been successfully used for the detection of egg and milk allergen in various food samples.

关键词： Liquid chromatography-tandem mass spectrometry Egg and milk allergen Signature peptides Isotope-labeled internal standards

Artificial intelligence standards system in medical treatment

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China Standardization 2020年第3期 49-49页

作者： Ma Xiaoou Shandong administration for market regulation

With the rapid development of artificial intelligence(AI)technologies,is it possible to use AI robots to deal with *** but dangerous work in medical emergency rescue?To promote the innovative development of medical in...

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