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Threshold effects of serum 25-hydroxyvitamin D levels on major depressive symptoms 认领 引用
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作者 Qinghua Fan Yi Guo +2 位作者 Zhongjian Liu Rongtian Xu Haibo Wang 《General Psychiatry》 CAS CSCD 2026年第1期71-75,共5页
To the Editor:Depression is a major contributor to the global burden of disease and disability,posing a critical public health challenge.Meta-analyses have demonstrated that vitamin D supplementation significantly red... To the Editor:Depression is a major contributor to the global burden of disease and disability,posing a critical public health challenge.Meta-analyses have demonstrated that vitamin D supplementation significantly reduces major depressive symptoms(MDS).1 However,recent large-scale randomised controlled trials(RCTs)2-4 have yielded conflicting evidence,indicating that vitamin D supplementation may not necessarily reduce MDS risk.This discrepancy may be attributed to variations in baseline serum 25-hydroxyvitamin D(25(OH)D)levels,insufficiently characterised doseresponse relationships and uncertain optimal 25(OH)D thresholds. 展开更多
关键词 threshold effects serum hydroxyvitamin D levels major depressive symptoms randomised controlled trials rcts vitamin d major depressive symptoms mds
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Influence of Outdoor Light at Night on Early Reproductive Outcomes of In Vitro Fertilization and Its Threshold Effect:Evidence from a Couple-Based Preconception Cohort Study 认领 引用
2
作者 Wenbin Fang Ying Tang +12 位作者 Yaning Sun Yanlan Tang Yinyin Chen Yawen Cao Jiqi Fang Kunjing He Yushan Li Yaning Dai Shuangshuang Bao Peng Zhu Shanshan Shao Fangbiao Tao Guixia Pan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2025年第8期1009-1015,共7页
Infertility,defined as the inability to achieve a clinical pregnancy after 1 year of unprotected and regular sexual intercourse,affects approximately 8%–12%of couples worldwide during their childbearing years.Assiste... Infertility,defined as the inability to achieve a clinical pregnancy after 1 year of unprotected and regular sexual intercourse,affects approximately 8%–12%of couples worldwide during their childbearing years.Assisted reproductive technology(ART)offers interventions to facilitate conception in couples with infertility.Since the inception of traditional in vitro fertilization(IVF)in 1978,ART has facilitated the birth of millions of infants.Intracytoplasmic sperm injection(ICSI)is an effective technique for couples ineligible for traditional IVF.Individual female factors,such as age and endometrial thickness,have been shown to affect embryo development during the IVF process,resulting in unfavorable pregnancy outcomes[1-3].However,the influence of environmental and male factors on early reproductive outcomes cannot be ignored.As a novel form of environmental pollution,light at night(LAN)has intensified with the rapid pace of urbanization,potentially leading to reproductive health problems in both women and men.However,to our knowledge,no study has explored the effects of LAN exposure on the early reproductive outcomes of IVF.Furthermore,the normal development of embryos relies on the contributions of both partners,and the influence of male factors on the early reproductive outcomes of IVF should not be overlooked. 展开更多
关键词 Preconception cohort study reproductive technology art offers vitro fertilization traditional vitro fertilization ivf Outdoor light night Early reproductive outcomes Threshold effect sperm injection icsi
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Association between Neutrophil-to-lymphocyte Ratio and Renal Function:A Cross-sectional Study with Threshold Effects 认领 引用
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作者 Lin Hu Mingcong Chen +3 位作者 Qiuwei Tian Zisai Wang Mingyi Zhao Qingnan He 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2025年第11期1458-1462,共5页
Chronic kidney disease(CKD)is a recognized global public health burden affecting over 15%of the general population[1].By 2040,CKD is expected to become the fifth-leading cause of death in the world[2].The neutrophil-t... Chronic kidney disease(CKD)is a recognized global public health burden affecting over 15%of the general population[1].By 2040,CKD is expected to become the fifth-leading cause of death in the world[2].The neutrophil-to-lymphocyte ratio(NLR)indicates local or systemic inflammation status.The NLR has been demonstrated to exhibit predictive value in various pathological conditions,including—but not limited to—pancreatic cancer,as well as macrovascular and microvascular diseases,and sepsis[3,4]. 展开更多
关键词 chronic kidney disease neutrophil lymphocyte ratio inflammation chronic kidney disease ckd public health burden threshold effects renal function
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Impact of digital economy development on carbon productivity:An empirical analysis based on threshold effect and spatial spillover effect 认领 引用
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作者 XING Huai-zhen YAO Jing 《Ecological Economy》 2024年第2期123-138,共16页
Utilizing provincial panel data from 2014 to 2020,this study employs a fixed effect model,a threshold effect model,and a spatial lag model to empirically examine the correlation between digital economic development an... Utilizing provincial panel data from 2014 to 2020,this study employs a fixed effect model,a threshold effect model,and a spatial lag model to empirically examine the correlation between digital economic development and carbon productivity.The findings indicate that digital economic development significantly contributes to the enhancement of carbon productivity in the long term.Furthermore,through instrumental variable method,replacement of explanatory variables and other methods to test its endogeneity and stability,the results remain robust.In terms of regional heterogeneity,the impact of digital economic development on carbon productivity is less pronounced in the central and western regions compared to the eastern region.Additionally,further investigation reveals that industrial structure upgrading and science and technology investment level exhibit different threshold effects on the influence of digital economy development level on carbon productivity.Moreover,there is a significant spatial spillover effect of digital economy development on carbon productivity with H-H and L-L agglomeration spatial correlation. 展开更多
关键词 digital economy carbon productivity threshold effect spatial spillover effect
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Research on the Threshold Effect of China’s Pharmaceutical Export Trade on Internal and External R&D Investment 认领 引用
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作者 Qiao Jiahui Song Yu +1 位作者 Gong Jingran Chen Yuwen 《Asian Journal of Social Pharmacy》 2024年第2期135-146,共12页
Objective To study the threshold effect of export trade on internal and external R&D investment in China’s pharmaceutical industry,and to provide reference for some pharmaceutical enterprises to improve the inves... Objective To study the threshold effect of export trade on internal and external R&D investment in China’s pharmaceutical industry,and to provide reference for some pharmaceutical enterprises to improve the investment.Methods The panel data of pharmaceutical industry in 25 provinces and cities in China from 2009 to 2019 were selected to conduct empirical analysis by establishing a threshold regression model,and a better export trade interval was obtained.Results and Conclusion There is a threshold value for the effect of new product export on both internal and external R&D expenditures,and the threshold values are 845.2788 million yuan and 318.4198 million yuan,respectively.There is a single threshold effect of export trade on both internal and external R&D investment in China’s pharmaceutical industry,and the effect of export trade on internal and external R&D investment changes from negative to positive as the export trade develops from low to high. 展开更多
关键词 pharmaceutical industry threshold effect export trade R&D investment
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Unraveling the threshold and interaction effects of environmental variables on cadmium contamination in rice grains 认领 引用 被引量：1
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作者 Yang Zeng Chen Shen +3 位作者 Bolun Zhang Jie Ren Zhanbin Huang Hong Hou 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2026年第2期450-460,共11页
Understanding Cd contamination in the soil-rice ecosystem and the underlying its threshold and interaction effects is crucial for controlling Cd pollution and ensuring food safety.Although the quantitative relationshi... Understanding Cd contamination in the soil-rice ecosystem and the underlying its threshold and interaction effects is crucial for controlling Cd pollution and ensuring food safety.Although the quantitative relationships between Cd and environmental variables have been extensively studied,the threshold and interaction effects of multi-source environmental variables remain largely unexplored.This study employs a combination of random forest analysis and a human health risk model to investigate the effects of variables on Cd levels in rice grains,with the goal of quantifying their contributions and elucidating their relationships.The results indicated that the 15 selected variables collectively explained 47.36%of the variation in Cd content,with the top three variables being soil pH,distance from industrial park,and soil Zn.The majority of variables exhibited threshold effects on Cd levels in rice grains.By visualizing the interaction between Soil pH,distance from industrial park,and soil Zn with Cd levels in rice,we demonstrate the threshold effects of them on Cd level in rice grains,thereby providing further insight into the variation observed.Furthermore,oral intake of rice has been identified as the primary route of human exposure,significantly contributing to overall exposure pathways.Understanding these interactions is crucial for gaining insights into the underlying processes driving Cd pollution and fostering sustainable development within the industry.Our findings underscore the crucial need to consider multiple environmental variables and their interactions when managing heavy metals(HMs)contamination and mitigating health risks. 展开更多
关键词 Heavy metals Rice Threshold effects Machine learning Health risk
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Research on the Impact of China’s Foreign Trade Technology Spillover on Green Total Factor Productivity of Countries Along the“Belt and Road”:Based on the Institutional Quality Threshold Effect 认领 引用
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作者 Li Chai Longnan Ma Lingwei Meng 《Proceedings of Business and Economic Studies》 2024年第2期120-125,共6页
China’s growing trade with countries along the“Belt and Road”Initiative is accompanied by a focus on green development.Based on the panel data from 2007 to 2018,this paper establishes a threshold regression model t... China’s growing trade with countries along the“Belt and Road”Initiative is accompanied by a focus on green development.Based on the panel data from 2007 to 2018,this paper establishes a threshold regression model to empirically analyze the institutional quality threshold effect of China’s foreign trade technology spillover on the GTFP of countries along the“Belt and Road.”The results show that China’s foreign trade technology spillover has a significant institutional quality double threshold effect on the green total factor productivity of the countries along the“Belt and Road.”As the institutional quality of the countries along the“Belt and Road”crosses a specific threshold value,the impact of China’s foreign trade technology spillover on the green total factor productivity of the countries along the“Belt and Road”has a significant positive promoting effect,and corresponding suggestions are put forward. 展开更多
关键词 Technology spillover Green total factor productivity Institutional quality Threshold effect
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Sustainability of Public Debt and Economic Growth in Cote d’Ivoire:is There a Threshold Effect? 认领 引用
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作者 Koffi Pokou 《Journal of Economic Science Research》 2020年第3期1-12,共12页
The development of Ivorian public debt in recent years has raised concerns.Is its current level capable of boosting the economy or,on the contrary,being at the source of a recession?This paper analyzes the effect of t... The development of Ivorian public debt in recent years has raised concerns.Is its current level capable of boosting the economy or,on the contrary,being at the source of a recession?This paper analyzes the effect of the level of indebtedness on economic growth in Côte d’Ivoire using the Threshold Autoregressive(TAR)model over the period 1970-2018.The results obtained in the short run shed light on the no relationship between public debt and economic growth.In the long run,on the other hand,there is a bi-directional granger causality between public debt and the sustainability of economic growth.The non-linearity between the variables of interest has been studied and the results show the presence of a threshold effect:beyond 48.03 percent of GDP,any increase in public debt by 1%should reduce economic growth by 0.28%.Thus,the study questions the relevance of the criterion set by the WAEMU:public debt<70%of GDP. 展开更多
关键词 Public debt and growth sustainability Threshold Autoregressive(TAR) Granger causality Threshold effects
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Threshold effect of residual catalyst on volume resistivity of polypropylene polymers 认领 引用
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作者 Xinhua Dong Zhen Luo +9 位作者 Tian Tan Mingti Wang Juan Li Qi Zhang Xiyu Zhang Shangshi Huang Yaru Zhang Wei Wang Qi Li Jinliang He 《High Voltage》 SCIE EI CSCD 2025年第4期939-952,共14页
Polypropylene(PP)has become the focus of research and development of recyclable polymer dielectric materials because of its excellent electrical and thermal properties.The residual catalyst after PP polymerisation is ... Polypropylene(PP)has become the focus of research and development of recyclable polymer dielectric materials because of its excellent electrical and thermal properties.The residual catalyst after PP polymerisation is the main part of ash.It was found that ash particles are uniformly dispersed in the PP matrix.The increase in ash content leads to a gradual decrease in their spacing,and leads to a significant decrease in electrical prop-erties,with a difference of more than one order of magnitude for volume resistivity.The decrease in the ion migration potential barrier caused by the increase of ash content is the key factor in deteriorating the electrical properties of PP.The effect of ash on the elec-trical properties of PP mainly lies in enhancing the migration of ion carriers.The PP volume resistivity corresponds to an ash threshold of 292 ppm,above which the con-centration leads to an increase in ion carriers.The accumulation of carriers leads to in-ternal electric field distortion enhancing the transition ability of carriers and leading to a rapid decrease in the electrical properties of PP.This study provides a feasible reference for the development of high-performance PP insulation materials for power cables and other applications. 展开更多
关键词 ion migration gradual decrease their volume resistivity recyclable polymer dielectric materials polypropylene threshold effect residual catalyst ash particles
How does plant diversity drive productivity in China’s drylands:Through complementary or mass ratio effects? 认领 引用
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作者 Hao Guo Hong-Hu Meng +4 位作者 Jin-Fei Yin Tong Li Ben-Feng Yin Xiao-Bing Zhou Yuan-Ming Zhang 《Plant Diversity》 SCIE CAS CSCD 2026年第4期766-781,共16页
Dryland biodiversity–productivity relationships remain poorly resolved.Specifically,the environmental conditions governing the shift between complementarity and mass ratio mechanisms remain unclear,limiting the effec... Dryland biodiversity–productivity relationships remain poorly resolved.Specifically,the environmental conditions governing the shift between complementarity and mass ratio mechanisms remain unclear,limiting the effectiveness of restoration and management strategies.To address this gap,the aim of this study was to investigate the geographical patterns of diversity and biomass production in herbaceous communities along a 2100-km precipitation gradient in North China.We studied howα-andβ-diversity affect community-wide productivity using linear mixed-effects models and piecewise structural equation models,along with rolling-window change-point analyses.In arid regions,biomass productivity was primarily driven by interspecificniche complementarity,where higher functional diversity(FD(α))enhanced resource-use efficiency.However,in semi-arid regions,productivity was regulated by the mass ratio effect,specificallythrough the traits of dominant species,including community weighted mean height and specificleaf area,as these species exploited broader resource spectra with increasing water availability.A critical mechanistic shift occurred at a mean annual precipitation(MAP)threshold of~168 mm(95%CI:152–171 mm;p<0.001).Below this threshold,productivity was driven by diversity-mediated complementarity and stress tolerant strategies.Conversely,as MAP surpassed 168 mm,the system transitioned to mass ratio control,coincident with a shift toward competitive strategies.Overall,our study provides empirical evidence to guide dryland management:prioritising the maintenance of functional diversity in arid communities,while emphasising dominant-trait optimisation(plant height and specificleaf area)in semi-arid communities to maximise aboveground biomass. 展开更多
关键词 Biodiversity Aboveground biomass(AGB) Complementarity effect Mass ratio effect CSR strategy Threshold effect
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Examining the Nonlinear Effects of Urban Population Polycentricity on Carbon Emissions Efficiency Using a Gradient Boosting Decision Tree Model:Evidence from 295 Chinese Cities 认领 引用
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作者 WANG Cheng YANG Xingzhu 《Chinese Geographical Science》 SCIE CAS CSCD 2026年第2期222-238,共17页
Transforming urban spatial structures to promote green and low-carbon development is an effective strategy.Although prior studies have examined the impact of urban polycentricity on carbon emissions and economic devel... Transforming urban spatial structures to promote green and low-carbon development is an effective strategy.Although prior studies have examined the impact of urban polycentricity on carbon emissions and economic development,research on its role in the synergistic relationship between these factors regarding carbon emission efficiency is limited.Furthermore,existing literature often overlooks nonlinear effects and interactions with other urban variables.This paper analyzed data from 295 Chinese cities in 2020,calculating urban population polycentricity,population dispersion indices,and carbon emission efficiency.Utilizing local spatial autocorrelation tools,we reveal interactions among urban population polycentricity,dispersion,carbon emissions,and carbon emission efficiency.We then employ a gradient boosting decision tree model(GBDT)to explore nonlinear and synergistic effects of polycentric urbanization.Key findings include:1)polycentric urbanization in Chinese cities exhibits significant spatial differentiation characteristics.The Polycentricity index is relatively high in economically developed eastern coastal regions with an overall low level,carbon emissions are concentrated in industrialized north-central cities and some Yangtze River Delta hubs,and carbon emission efficiency is the highest in the Yangtze River Delta while relatively low in Northeast China;there are significant spatially heterogeneous interaction characteristics among population polycentricity,population dispersion,carbon emissions,and carbon emission efficiency.2)Urban population polycentricity contributes 9.42%to total carbon emissions and 6.24%to carbon emission efficiency.3)The polycentricity index has a nonlinear impact on carbon emissions and carbon emission efficiency:no significant effect when below 0.50 or above 0.55,increased carbon emissions in 0.50-0.53,and reduced carbon emissions with improved efficiency in 0.53-0.55.4)The polycentricity index has an interaction effect with other variables;specifically,when the polycentricity index is between 0.53 and 0.55,its interaction with urban gross domestic product(GDP),urban population,urban built-up area,green coverage rate in built-up areas,urban technological expenditure,and the proportion of the output value of the secondary industry will reduce carbon emissions and improve carbon emission efficiency.These findings enhance the understanding of urban spatial structures and carbon emissions,providing valuable insights for policymakers in developing green and low-carbon strategies. 展开更多
关键词 urban polycentricity carbon emission efficiency gradient boosting decision tree(GBDT) nonlinear threshold effects Chinese cities
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Exploring the optimal nitrogen threshold for global grassland restoration 认领 引用
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作者 Qi Zhang Fu Chen +12 位作者 Zhanbin Luo Jun Fan Yanfeng Zhu Jing Ma Yongjun Yang Xi-en Long Alejandro Gonzalez-Ollauri Miao Gan Weihong Guo Yuxiang Ma Qiaoling Wang Shenglu Zhou Mingan Shao 《Geography and Sustainability》 CSCD 2026年第1期66-81,共16页
Amid accelerating global land degradation,establishing high-efficiency ecological restoration principles and frameworks is crucial.Here,we explore the application of threshold effects in the ecological restoration pro... Amid accelerating global land degradation,establishing high-efficiency ecological restoration principles and frameworks is crucial.Here,we explore the application of threshold effects in the ecological restoration process based on field experiments and globally available experimental data from 173 sites.Combining data integration analysis and meta-analysis,we collectively verified the universality of threshold effects in grasslands.The global grasslands’average nitrogen application threshold is 3.78 g·m-2·yr−1,while the threshold value of degraded grassland(3.65 g·m-2·yr−1)is lower than that of nondegraded grassland(5.90 g·m-2·yr−1).The low nitrogen-driven thresholds are affected by degradation status,climate(precipitation and temperature),and other site conditions,but not fertilization forms.Independent experiments further demonstrated that an increase in soil moisture content can lead to the disappearance of nitrogen threshold effects,revealing that ecological threshold effects are influenced by ecosystem stress factors.Following the significant increase in plant biomass triggered by the nitrogen threshold,the ecosystem undergoes systemic improvement.Soil organic carbon,urease activity,soil microbial diversity,and other soil properties are significantly enhanced.Soil nitrogen cycle-related microbial communities and soil physicochemical attributes are significantly activated.The results indicate that a threshold response pattern may develop before nitrogen saturation is reached,and low nitrogen input can boost productivity and improve the plant-soil-microbe system.Our findings reveal a nonprogressive path of restoration in degraded ecosystems,and thus,restoration based on threshold effects can offer an efficient and safe solution to combat ecological degradation. 展开更多
关键词 Ecological restoration Thresholds effect Grassland Nitrogen Meta-analysis
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Soil microbial communities regulate the threshold effect of salinity stress on SOM decomposition in coastal salt marshes 认领 引用 被引量：7
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作者 Guangliang Zhang Junhong Bai +5 位作者 Jia Jia Wei Wang Dawei Wang Qingqing Zhao Chen Wang Guozhu Chen 《Fundamental Research》 CAS CSCD 2023年第6期868-879,共12页
Salinity stress is one of the critical environmental drivers of soil organic matter(SOM)decomposition in coastal ecosystems.Although the temperature sensitivity(Q10)of SOM decomposition has been widely applied in E... Salinity stress is one of the critical environmental drivers of soil organic matter(SOM)decomposition in coastal ecosystems.Although the temperature sensitivity(Q10)of SOM decomposition has been widely applied in Earth system models to forecast carbon processes,the impact of salinity on SOM decomposition by restructuring microbial communities remains uncovered.Here,we conducted a microcosm experiment with soils collected from the coastal salt marsh in the Yellow River Estuary,which is subjected to strong dynamics of salinity due to both tidal flooding and drainage.By setting a gradient of salt solutions,soil salinity was adjusted to simulate salinity stress and soil carbon emission(CO2)rate was measured over the period.Results showed that as salinity increased,the estimated decomposition constants based on first-order kinetics gradually decreased at different temperatures.Below the 20‰salinity treatments,which doubled the soil salinity,Q10increased with increasing salinity;but higher salinity constrained the temperature-related response of SOM decomposition by inhibiting microbial growth and carbon metabolisms.Soil bacteria were more sensitive to salinity stress than fungi,which can be inferred from the response of microbial beta-diversity to changing salinity.Among them,the phylotypes assigned to Gammaproteobacteria and Bacilli showed higher salt tolerance,whereas taxa affiliated with Alphaproteobacteria and Bacteroidota were more easily inhibited by the salinity stress.Several fungal taxa belonging to Ascomycota had higher adaptability to the stress.As the substrate was consumed with the incubation,bacterial competition intensified,but the fungal co-occurrence pattern changed weakly during decomposition.Collectively,these findings revealed the threshold effect of salinity on SOM decomposition in coastal salt marshes and emphasized that salt stress plays a key role in carbon sequestration by regulating microbial keystone taxa,metabolisms,and interactions. 展开更多
关键词 Salt marshes Salinity stress Soil organic matter decomposition Temperature sensitivity Threshold effect Microbial community
The Threshold Effect of Rationalization of Industrial Structure on Air Quality in Shanxi Province 认领 引用 被引量：5
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作者 ZHU Meifeng WU Qinglong +1 位作者 ZHANG Huaming CHEN Zhanbo 《Journal of Resources and Ecology》 CSCD 2020年第2期206-212,共7页
Shanxi Province is a typical resource-based region. After years of economic transformation, the air quality has been at a low level for a long time. The rationalization of industrial structure can measure the effect o... Shanxi Province is a typical resource-based region. After years of economic transformation, the air quality has been at a low level for a long time. The rationalization of industrial structure can measure the effect of economic transformation and whether it has an important impact on air quality. Therefore, it is necessary to study the non-linear impact that the rationalization of industrial structure has had on air quality at different stages, which is of positive significance for the continuing transformation and upgrading of resource-based regions. This study constructs a threshold regression model based on the panel data of 11 provincial cities in Shanxi Province from 2004 to 2016. The results show that the rationalization of industrial structure had a double threshold effect on air quality under different threshold variables. On the whole, optimizing the rationalization of industrial structure in Shanxi Province can improve air quality, and the improvement effect dropped first, and then began to rise. As a result, the current energy transformation and upgrading process should focus on the rationalization of industrial structure to solve the conflict between air quality and economic development. 展开更多
关键词 rationalization of industrial structure air quality threshold effect Shanxi Province
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Productivity Spillovers from FDI in China:Regional Differences and Threshold Effects 认领 引用 被引量：4
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作者 Jianhong Qi Yingmei Zheng +1 位作者 James Laurenceson Hong Li 《China & World Economy》 2009年第4期18-35,共18页
Economic theory posits numerous channels through which FDI might create positive spillovers for domestic firms. However, the results of empirical studies that have sought to document these spillovers have been mixed. ... Economic theory posits numerous channels through which FDI might create positive spillovers for domestic firms. However, the results of empirical studies that have sought to document these spillovers have been mixed. One explanation for this variation is that the capacity of domestic firms to absorb spillovers might vary. In the present paper, we explore these issues in the case of China. ,4side from being one of the world＇s leading hosts offoreign direct investment, China makes for an interesting case study because its provinces vary greatly with respect to those factors most commonly held to influence absorptive capacity, such as the initial level of technology in domestic firms. This paper begins by empirically establishing that the spillovers from foreign direct investment do indeed vary across provinces. Threshold values for varioas factors that influence absorptive capacity factors are then estimated and it is found that conditions in many provinces presently fall short of these values. This provides an obvious focus of attention for China＇s policy-makers. 展开更多
关键词 Data Envelopment Analysis foreign direct investment productivity spillovers threshold effects
Manufacturing Demand and Producer Services Efficiency in China:Threshold Effect of Economic Development 认领 引用
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作者 Wen Wang Zao Sun 《China Finance and Economic Review》 2018年第4期48-70,共23页
Considering the important role the demand from manufacturing has played in the development of producer services,this paper analyzes the influence mechanism of manufacturing demand on producer services efficiency throu... Considering the important role the demand from manufacturing has played in the development of producer services,this paper analyzes the influence mechanism of manufacturing demand on producer services efficiency through two channels,which are the scale effect and innovation incentives.Meanwhile,the paper also evaluates the moderating effect of economic development level on the relationship between manufacturing demand and producer services efficiency.Based on the panel data of China’s manufacturing industry and producer services from 1995 to 2014,the empirical result shows that:(1)the demand from manufacturing was helpful to improve producer services efficiency,and compared with the labor-intensive manufacturing,the demand from capital-intensive manufacturing played a more important role in improving producer services efficiency;(2)at different stages of economic development,the promoting effect of manufacturing demand on producer services efficiency showed a nonlinear threshold effect rather than a simple linear effect,namely after crossing a certain threshold of economic development level,the promoting effect would be more significant.More specifically the threshold level faced by capital-intensive manufacturing industry was higher than that faced by labor-intensive manufacturing industry.These findings may be helpful for governments to make industrial development strategy. 展开更多
关键词 manufacturing demand producer services efficiency economic development level threshold effect
Identification of ecological priority area based on thresholds of impacts of natural factors on ecosystem services,Qinghai-Tibetan plateau 认领 引用
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作者 Jian Xue Zongxing Li +2 位作者 Liqin Yang Juan Gui Fa Du 《Ecological Frontiers》 CSCD 2025年第4期1083-1096,共14页
Ecosystem services(ESs)are an important bridge coupling the natural environment and human society.The Qinghai-Tibetan Plateau(QTP),as an ecological barrier in China and even in Asia,plays a key role in maintaining reg... Ecosystem services(ESs)are an important bridge coupling the natural environment and human society.The Qinghai-Tibetan Plateau(QTP),as an ecological barrier in China and even in Asia,plays a key role in maintaining regional ecological security and sustainable supply of water resources.However,there is limited research of determining thresholds and zoning on ESs over long periods of time.This study took the QTP as study region,analyzed the characteristics of spatial and temporal variations of ESs,determined the impact thresholds of precipitation(Pre),temperature(Tem),evapotranspiration(ET)and Fractional Vegetation Cover(FVC)on ESs,and identified the ecological priority area(EPA)of the QTP.The results showed that all ESs increased of different degrees from 2000 to 2022.The coefficient of variation(CV)of water yield(WY),haibitat quality(HQ),carbon storage(CS),soil retention(SR),climate regulation(CR)and food supply(FS)was 0.32,0.18,0.12,0.2,0.21 and 0.15.Based on the impact thresholds of Pre,Tem,ET and FVC on ESs,EPA of each ES was identified.The EPA of WY,HQ,CS,SR,CR and FS was 95×104km2,74×104km2,47×104km2,64×104km2,80×104km2and 92×104km2,which provided theoretical support for the ecological restoration and sustainable development of the QTP. 展开更多
关键词 Ecosystem service Threshold effect Ecological priority area Qinghai-Tibetan Plateau
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Effect of Straw Incorporation on the Specificity of Zn,Cd,and Pb Reduction and As Accumulation in Saline-Alkali Paddy Soil and Rice Yield 认领 引用
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作者 MA Li-na WANG Bai +1 位作者 TENG Ze-yu CHEN Zhi-wen 《Agricultural Science & Technology》 2025年第4期22-30,共9页
Through field location experiments,the effect of straw incorporation on soil heavy metals and rice yield in saline-alkali paddy fields in the western part of the Songnen Plain was explored.The results indicated that s... Through field location experiments,the effect of straw incorporation on soil heavy metals and rice yield in saline-alkali paddy fields in the western part of the Songnen Plain was explored.The results indicated that straw incorporation exhibited significant element-specific regulation of soil heavy metals.It markedly reduced soil Zn,Cd and Pb content,while markedly increasing As content.The As content exhibited a non-linear increase with the rise in straw incorporation rate,with increases of 3.81%-6.69%.Significant differences were observed among treatments S0,S1,and S2,whereas no significant differences existed among treatments S2,S3,and S4,suggesting a saturation threshold(50%)for As accumulation under straw incorporation.In addition,straw incorporation exhibited a yield threshold,with the maximum rice yield occurring at 100%straw incorporation and yield decreased beyond 150%straw incorporation.In conclusion,the appropriate straw incorporation rate was 100%for the saline-alkali paddy fields in the western part of the Songnen Plain. 展开更多
关键词 Rice straw incorporation Saline-alkali soil Heavy metal content As threshold effect Specific effect
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Effect of β_3-adrenoceptors on Ventricle Fibrillation Threshold and Effective Refractory Period in Rats With Heart Failure 认领 引用
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作者 Deng Yijun Wu Wei Huang Zhibing Fang Chang 《South China Journal of Cardiology》 CAS 2006年第2期73-77,共5页
Objectives To observe the effect of β3-Adrenoceptor （AR） on ventricle fibrillation threshold （VFT） and effective refractory period （ERP） in rats with heart failure. Methods Rats were randomized into control gro... Objectives To observe the effect of β3-Adrenoceptor （AR） on ventricle fibrillation threshold （VFT） and effective refractory period （ERP） in rats with heart failure. Methods Rats were randomized into control group and heart failure group. The expression of β3-ARmRNA was detected with RTPCR; The VFT, ERP, LVESP,LVEDP, ＋dp/dtmax and -dp/dtmax was measured at the same time with administration of BRL37344 （ 2 nmol / kg, β3- AR agonist）. Results ①Both the expression of β3-AR mRNA and the proportion increased in rats with heart failure in comparison with control rats （0.028 vs. 0.011 and 5.4% vs 1.2%, P 〈 0.05）;② ERP was longer in rats with heart failure than control group （70.5±5.5 ms vs 59.5±6.4ms, P 〈 0.05） and there was no difference of ERP in rats with heart failure with administration of BRL37344 （73.0±4.8 ms vs 70.5± 5.5 ms, P 〉0.05）; ③VFT was lower in rats with heart failure than control group（10.9±0.8 mv vs 30.5± 1.3 mv, P〈 0.05） and decreased obviously in rats with heart failure with administration of BRL37344 （7.1±0.6 mv vs 10.9±0.8 mv, P 〈 0.05） ; The decrease of VFT correlated with the effect on LVESP, ＋dp/ dtmax,-dp/dtmax of BRL37344 and the expression of β3-AR mRNA （correlation coefficient： 0.788, 0.708, 0.759, 0.787; P 〈 0.05）. Conclusions The expression of β3-AR mRNA of left ventricle was obviously increased in rats with heart failure, and activation of β3-AR had no effect on ERP but could decreased VFT which correlated with the effect of β3-AR on LVESP, ＋dp/dtmax, -dp/dtmax and the expression of β3-AR mRNA. 展开更多
关键词 β3-adrenoceptors Ventricle fibrill-ation threshold Effective refractory period
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Semiclassical investigation of Coulomb focusing effects in atomic above-threshold ionization with elliptically polarized laser fields 认领 引用
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作者 王传亮 夏立新 +1 位作者 姚洪斌 李文亮 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第4期156-161,共6页
We investigate atomic above-threshold ionization in elliptically polarized strong laser fields with a semiclassical approach.With increasing laser intensity,the Coulomb focusing（CF） effects are found to become stron... We investigate atomic above-threshold ionization in elliptically polarized strong laser fields with a semiclassical approach.With increasing laser intensity,the Coulomb focusing（CF） effects are found to become stronger in both parallel and perpendicular directions with respect to the polarization plane.The dependence of CF effects on tunnel exit,initial transverse momentum distribution and laser electric field is analyzed.It was revealed that the effects of tunnel exit are most prominent with variation of the laser intensity,and the other two factors both play non-negligible roles.Our results provide a deeper insight to the recent experiments of Coulomb asymmetry[Shafir D,et al.,2013 Phys.Rev.Lett.111 023005 and Li M,et al,2013 Phys.Rev.Lett.111 023006]. 展开更多
关键词 above-threshold ionization Coulomb focusing effect semiclassical method elliptically polarized laser fields
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