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Research Progress and Prospects of Total Factor Productivity in the Construction Industry
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作者 Chen WANG Shijie YU +2 位作者 Chenhao LIANG Lidan CAI Xiaohong XIONG 《Asian Agricultural Research》 2024年第7期39-41,共3页
The high-quality development of the construction industry fundamentally stems from the significant improvement of total factor productivity.Therefore,it is of crucial significance for promoting the development of the ... The high-quality development of the construction industry fundamentally stems from the significant improvement of total factor productivity.Therefore,it is of crucial significance for promoting the development of the construction industry to a higher level by scientifically and accurately measuring the total factor productivity of the construction industry and deeply analyzing the influencing factors behind it.Based on a comprehensive consideration of research methods and influencing factors,this paper systematically reviews the existing relevant literature on total factor productivity in the construction industry,aiming to reveal the current research development trend in this field and point out potential problems.This effort aims to provide a solid theoretical foundation and valuable reference for further in-depth research,and jointly promote the continuous progress and development of total factor productivity research in the construction industry. 展开更多
关键词 Construction industry Total factor productivity Research progress Influence factor Theoretical basis
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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
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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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The hypoxia-inducible factor-1α activates ectopic production of fibroblast growth factor 23 in tumor-induced osteomalacia 被引量:8
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作者 Qian Zhang Michele Doucet +4 位作者 Ryan E Tomlinson Xiaobin Han L Darryl Quarles Michael T Collins Thomas L Clemens 《Bone Research》 SCIE CAS CSCD 2016年第2期85-90,共6页
Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome in which ectopic production of fibroblast growth factor 23 (FGF23) by non-malignant mesenchymal tumors causes phosphate wasting and bone fractures... Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome in which ectopic production of fibroblast growth factor 23 (FGF23) by non-malignant mesenchymal tumors causes phosphate wasting and bone fractures. Recent studies have implicated the hypoxia-inducible factor-la (HIF-la) in other phosphate wasting disorders caused by elevated FGF23, including X-linked hypophosphatemic rickets and autosomal dominant hypophosphatemia. Here we provide evidence that HIF-la mediates aberrant FGF23 in TIO by transcriptionally activating its promoter. Immunohistochemical studies in phosphaturic mesenchymal tumors resected from patients with documented TIO showed that HIF-la and FGF23 were co-localized in spindle- shaped cells adjacent to blood vessels. Cultured tumor tissue produced high levels of intact FGF23 and demonstrated increased expression of HIF-la protein. Transfection of MC3T3-E1 and Saos-2 cells with a HIF-la expression construct induced the activity of a FGF23 reporter construct. Prior treatment of tumor organ cultures with HIF-la inhibitors decreased HIF-la and FGF23 protein accumulation and inhibited HIF-la-induced luciferase reporter activity in transfected cells. Chromatin immunoprecipitation assays confirmed binding to a HIF-la consensus sequence within the proximal FGF23 promoter, which was eliminated by treatment with a HIF-la inhibitor. These results show for the first time that HIF-la is a direct transcriptional activator of FGF23 and suggest that upregulation of HIF-la activity in TIO contributes to the aberrant FGF23 production in these patients. 展开更多
关键词 The hypoxia-inducible factor-1 activates ectopic production of fibroblast growth factor 23 in tumor-induced osteomalacia HIF
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Geological characteristics and high production control factors of shale gas reservoirs in Silurian Longmaxi Formation, southern Sichuan Basin, SW China 被引量:6
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作者 MA Xinhua XIE Jun +1 位作者 YONG Rui ZHU Yiqing 《Petroleum Exploration and Development》 2020年第5期901-915,共15页
Marine shale gas resources have great potential in the south of the Sichuan Basin in China.At present,the high-quality shale gas resources at depth of 2000–3500 m are under effective development,and strategic breakth... Marine shale gas resources have great potential in the south of the Sichuan Basin in China.At present,the high-quality shale gas resources at depth of 2000–3500 m are under effective development,and strategic breakthroughs have been made in deeper shale gas resources at depth of 3500–4500 m.To promote the effective production of shale gas in this area,this study examines key factors controlling high shale gas production and presents the next exploration direction in the southern Sichuan Basin based on summarizing the geological understandings from the Lower Silurian Longmaxi Formation shale gas exploration combined with the latest results of geological evaluation.The results show that:(1)The relative sea depth in marine shelf sedimentary environment controls the development and distribution of reservoirs.In the relatively deep water area in deep-water shelf,grade-I reservoirs with a larger continuous thickness develop.The relative depth of sea in marine shelf sedimentary environment can be determined by redox conditions.The research shows that the uranium to thorium mass ratio greater than 1.25 indicates relatively deep water in anoxic reduction environment,and the uranium to thorium mass ratio of 0.75–1.25 indicates semi-deep water in weak reduction and weak oxidation environment,and the uranium to thorium mass ratio less than 0.75 indicates relatively shallow water in strong oxidation environment.(2)The propped fractures in shale reservoirs subject to fracturing treatment are generally 10–12 m high,if grade-I reservoirs are more than 10 m in continuous thickness,then all the propped section would be high-quality reserves;in this case,the longer the continuous thickness of penetrated grade-I reservoirs,the higher the production will be.(3)The shale gas reservoirs at 3500–4500 m depth in southern Sichuan are characterized by high formation pressure,high pressure coefficient,well preserved pores,good pore structure and high proportion of free gas,making them the most favorable new field for shale gas exploration;and the pressure coefficient greater than 1.2 is a necessary condition for shale gas wells to obtain high production.(4)High production wells in the deep shale gas reservoirs are those in areas where Long11-Long13 sub-beds are more than 10 m thick,with 1500 m long horizontal section,grade-I reservoirs penetration rate of over 90%,and fractured by dense cutting+high intensity sand injection+large displacement+large liquid volume.(5)The relatively deep-water area in the deep-water shelf and the area at depth of 3500–4500 m well overlap in the southern Sichuan,and the overlapping area is the most favorable shale gas exploration and development zones in the southern Sichuan in the future.With advancement in theory and technology,annual shale gas production in the southern Sichuan is expected to reach 450×108 m3. 展开更多
关键词 southern Sichuan Basin Lower Silurian Longmaxi Formation deeply buried shale gas high production control factors deep water and deep burial shale gas reservoir
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Does innovative city pilot policy promote urban green growth in China?An analysis of green total factor productivity,2005-2020 被引量:1
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作者 Hao Zhang Wenqing Tao Jun He 《Chinese Journal of Population,Resources and Environment》 2023年第3期145-154,共10页
The innovative city pilot policy(ICPP)is an essential manifestation of China’s construction of an innovative and green-driven development country.We incorporated urban green total factor productivity(GTFP)growth into... The innovative city pilot policy(ICPP)is an essential manifestation of China’s construction of an innovative and green-driven development country.We incorporated urban green total factor productivity(GTFP)growth into the evaluation of ICPP.Based on the panel data of 223 cities in China from 2005 to 2020,we used the difference-in-differences model to empirically assess the influence and mechanism of the ICPP on urban GTFP growth.The main results show that(i)The ICPP has maintained an effectively fluctuating promotion on urban GTFP growth,mainly manifested in the urban green technological progress improvement.(ii)The ICPP has urban heterogeneity in promoting GTFP growth in pilot cities,mainly affecting key cities such as provincial capitals.(iii)The interaction between the agglomeration of producer services and the ICPP inhibits GTFP growth in pilot cities. 展开更多
关键词 Innovative city pilot policy Urban green total factor productivity growth Industrial agglomerations Difference-in-differences model methodology
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EFFECTS OF PHYTOLACCA ACINOSA POLYSACCHARIDES I ON CYTOTOXICITY OF MACROPHAGES AND ITS PRODUCTION OF TUMOR NECROSIS FACTOR AND INTERLEUKIN 1
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作者 张俊平 钱定华 郑钦岳 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1990年第4期16-19,共4页
The in vivo effects of Phytolacca acinosa poly-saccharides I (PEP-I) on immunologic cytotoxicity of mouse peritoneal macrophages and its production of tumor necrosis factor (TNF) and interleukin 1 (IL-1) were studied.... The in vivo effects of Phytolacca acinosa poly-saccharides I (PEP-I) on immunologic cytotoxicity of mouse peritoneal macrophages and its production of tumor necrosis factor (TNF) and interleukin 1 (IL-1) were studied. PEP-I 80 or 160 mg kg was given ip twice every 4 day. Both doses were found to have significant enhancing activity on macrophages cytotoxicity against S180 sarcoma cells and malignant transformed fibroblast L929 cells. Peritoneal activated macrophages were incubated with LPS for 2 and 24 hrs to induce TNF and IL-1, respectively. The TNF and IL-1 activities were tested from cytotoxicity against L929 cells in an absorbence assay of enzymatic reaction and proliferation of thymocytes co-stimulated assay separately. The optimal time for TNF production was found on day 8. Significant increases in TNF and IL-1 were observed. In comparison of the effect of PEP-I on TNF with that of known priming agent BCG, there was no difference between them, but PEP-I had a high effect on IL-1. These results suggest that cytotoxicity of macrophages primed by PEP-I is closely related to its TNF and IL-1 production. 展开更多
关键词 PEP EFFECTS OF PHYTOLACCA ACINOSA POLYSACCHARIDES I ON CYTOTOXICITY OF MACROPHAGES AND ITS production OF TUMOR NECROSIS factor AND INTERLEUKIN 1 TNF
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An Empirical Study on the Influence of Agricultural Public Infrastructure on Total Factor Productivity of China’s Grain Production
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作者 Yang Yu Pan Yueping 《Contemporary Social Sciences》 2022年第3期20-36,共17页
A critical method of ensuring grain production is to increase the total factor productivity(TFP),and the key measure to increase the TFP of grain production lies in the construction of agricultural public infrastructu... A critical method of ensuring grain production is to increase the total factor productivity(TFP),and the key measure to increase the TFP of grain production lies in the construction of agricultural public infrastructure.For this topic,existing literature lacks systematic and empirical analysis.Therefore,research on the influence of agricultural public infrastructure on the TFP of China’s grain production has relatively strong policy implications and theoretical value.For this study,we collected panel data for grain inputs and outputs as well as for agricultural public infrastructure in China’s provinces(autonomous regions/municipalities)from 1990 to 2017,and adopted the stochastic frontier function(SFF)approach to measure the TFP of provincial-level grain production.Through this empirical study,we analyzed the influence of agricultural public infrastructures,such as irrigation,roads,and electric power facilities on the TFP of China’s agriculture.We found that such facilities have a positive influence on the TFP of grain production.Specifically,when the input for irrigation facilities is increased by 1 percent,the TFP of grain production will rise by 5.74 percent.Based on this finding,policy recommendations are proposed for enhancing grain TFP through agricultural public infrastructure construction. 展开更多
关键词 agricultural public infrastructure grain production total factor productivity empirical analysis
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Methodological factors affecting gas and methane production during in vitro rumen fermentation evaluated by meta-analysis approach
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作者 Laura Maccarana Mirko Cattani +3 位作者 Franco Tagliapietra Stefano Schiavon Lucia Bailoni Roberto Mantovani 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2017年第1期236-247,共12页
Effects of some methodological factors on in vitro measures of gas production(GP, mL/g DM), CH4production(mL/g DM) and proportion(% CH4 on total GP) were investigated by meta-analysis. These factors were conside... Effects of some methodological factors on in vitro measures of gas production(GP, mL/g DM), CH4production(mL/g DM) and proportion(% CH4 on total GP) were investigated by meta-analysis. These factors were considered:pressure in the GP equipment(0 = constant; 1 = increasing), incubation time(0 = 24; 1 = ≥ 48 h), time of rumen fluid collection(0 = before feeding; 1 = after feeding of donor animals), donor species of rumen fluid(0 = sheep; 1 =bovine), presence of N in the buffer solution(0 = presence; 1 = absence), and ratio between amount of buffered rumen fluid and feed sample(BRF/FS; 0 = ≤ 130 mL/g DM; 1 = 130–140 mL/g DM; 2 = ≥ 140 mL/g DM). The NDF content of feed sample incubated(NDF) was considered as a continuous variable. From an initial database of 105 papers, 58 were discarded because one of the above-mentioned factors was not stated. After discarding 17 papers,the final dataset comprised 30 papers(339 observations). A preliminary mixed model analysis was carried out on experimental data considering the study as random factor. Variables adjusted for study effect were analyzed using a backward stepwise analysis including the above-mentioned variables. The analysis showed that the extension of incubation time and reduction of NDF increased GP and CH4 values. Values of GP and CH4 also increased when rumen fluid was collected after feeding compared to before feeding(+26.4 and +9.0 mL/g DM, for GP and CH4),from bovine compared to sheep(+32.8 and +5.2 mL/g DM, for GP and CH4), and when the buffer solution did not contain N(+24.7 and +6.7 mL/g DM for GP and CH4). The increase of BRF/FS ratio enhanced GP and CH4production(+7.7 and +3.3 mL/g DM per each class of increase, respectively). In vitro techniques for measuring GP and CH4 production are mostly used as screening methods, thus a full standardization of such techniques is not feasible. However, a greater harmonization of analytical procedures(i.e., a reduction in the number of available protocols) would be useful to facilitate comparison between results of different experiments. 展开更多
关键词 Experimental factors Gas production In vitro rumen fermentation Meta-analysis Methane production
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The Impact of the Establishment of National High-tech Zones on Total Factor Productivity of Chinese Enterprises
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作者 Wang Mingyi Liu Xiaoyu 《China Economist》 2023年第3期68-93,共26页
The National High-tech Zone(NHTZs)is an important strategic platform for cultivating high-tech industries and realizing high-quality economic development in China.Based on the combined data from 2006 to 2014 of the in... The National High-tech Zone(NHTZs)is an important strategic platform for cultivating high-tech industries and realizing high-quality economic development in China.Based on the combined data from 2006 to 2014 of the industrial enterprise database,the customs database,and the China Development Zones Audit and Announcement Catalogue(abbreviated asthe Catalogue),this paper systematically investigates the influence of the construction of NHTZs on enterprise’s total factor productivity(TFP).Results show that NHTZs have a positive impact on the TFP of enterprises in the zone,and this conclusion is still valid after considering endogeneity problems.Furthermore,the above productivity effects of NHTZs are heterogeneous in terms of enterprise ownership,external environment and establishment time,and NHTZs have greater stimulation effects on enterprise productivity after comparing with other types of functional zones.An investigation of the specific mechanisms at play shows that NHTZs promote the TFP of enterprises in the zone through the release of preferential policies,strengthening the“technology spillover effects”of imported intermediate goods,enhancing enterprise’s innovation ability and attracting talent.In addition,based on the decomposition of industry productivity,this paper also investigates the impact of NHTZs on changes in industry productivity and finds that NHTZs promote the overall productivity of specific industries mainly by stimulating the productivity improvement of incumbent enterprises and expanding the market share of high-productivity enterprises.Moreover,the preferential policies of NHTZs do not significantly stimulate high-productivity enterprises to enter the zones,nor do they cause low-productivity enterprises to exit.This research is helpful in objectively evaluating the economic effects of the NHTZs in China and in providing a theoretical basis for its further adjustment. 展开更多
关键词 National High-tech Zones(NHTZs) total factor productivity(TFP) DIFFERENCE-IN-DIFFERENCES changes in industry productivity
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Empirical Analysis of the Impact of Green Finance and Technological Progress on Total Factor Productivity in China’s Industrial Sector
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作者 Yingying Zhou Guoqiang Chen +3 位作者 Lujiu Huang Zhihao Lin Jing Jin Fengran Lu 《Proceedings of Business and Economic Studies》 2023年第6期39-44,共6页
The enhancement of industrial green total factor productivity is pivotal for achieving high-quality and sustainable economic development.This study assesses China’s performance using the SBM-GML model,employing provi... The enhancement of industrial green total factor productivity is pivotal for achieving high-quality and sustainable economic development.This study assesses China’s performance using the SBM-GML model,employing province-level panel data spanning from 2004 to 2020.Furthermore,we examine the influence of green finance and technological progress on industrial green total factor productivity using a spatial econometric model.The findings uncover that the relationship between the level of green financial development and industrial green total factor productivity follows a U-shaped curve.Initially,low levels of green financial development exert a suppressive effect on industrial green total factor productivity,proving ineffective in the short term.However,with the progression of green finance development,a positive and significant long-term impact on industrial green total factor productivity emerges.Moreover,technological progress demonstrates a noteworthy promotional effect on industrial green total factor productivity.The analysis delves deeper into revealing that industrial structure and environmental regulation intensity exhibit a significant negative relationship with industrial green total factor productivity.In contrast,both energy structure and education level showcase a substantial positive relationship with industrial green total factor productivity. 展开更多
关键词 Industrial green total factor productivity Green finance Technological progress
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Data as a Factor of Production Promoting the Deep Integration of the Digital Economy and the Real Economy:Theoretical Logic and Analysis Framework
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作者 OUYANG Rihui 《Frontiers of Economics in China-Selected Publications from Chinese Universities》 2024年第2期129-153,共25页
Data is the primary factor of production in the digital economy,playing a role in promoting the deep integration of the digital economy and the real economy and smoothing the national economic cycle.After entering the... Data is the primary factor of production in the digital economy,playing a role in promoting the deep integration of the digital economy and the real economy and smoothing the national economic cycle.After entering the circulation system of the real economy,data is rapidly integrated into production,circulation,consumption,distribution,and other links.It optimizes resource allocation,unblocks circulation channels,promotes accurate matching of supply and demand,stimulates emerging demand,and forms a virtuous circle of digital technology application,traditional physical enterprise transformation,and technological innovation.Integrated development is an important feature of the digital economy.Data promotes the integration of factors of production,products,enterprises,industries,and markets,which fosters a circular system with deep integration of the digital economy and the real economy.To promote the deep integration of the digital economy and the real economy,the government and business entities should take measures to improve the circular efficiency of the digital economy and the real economy.These measures include attaching importance to the role of data-driven development,improving data capacity,data development,and utilization in enterprises,exploring diverse circulation models of enterprise data,and creating typical application scenarios and industrial data spaces. 展开更多
关键词 DATA data as a factor of production(data factor) digital economy real economy integrated development
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Do smart city policies improve energy efficiency?Evidence from China
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作者 Zhilong Qin Haoming Yang +2 位作者 Lei Shi Ouyang Ying Wenhan Liu 《Chinese Journal of Population,Resources and Environment》 2024年第2期185-193,共9页
To address air pollution and offer a convenient and comfortable living environment,the Chinese government launched a smart city pilot(SCP)project in 2012,accompanied by a comprehensive set of environmental and energy-... To address air pollution and offer a convenient and comfortable living environment,the Chinese government launched a smart city pilot(SCP)project in 2012,accompanied by a comprehensive set of environmental and energy-related laws and regulations.Although academic interest in smart cities has surged,there remains a notable gap in empirical research exploring the economic,environmental,and energy effects of such initiatives.Taking 232 prefecture-level cities from 2003 to 2017 as research subjects,this study measures energy effi‐ciency by using energy consumption per unit of GDP and adopts a difference-in-differences(DID)analysis to investigate the impact of SCPs on energy efficiency.The empirical results indicate that SCPs improved energy efficiency by promoting urban technological innovation capabilities and green total factor productivity,and this effect was more pronounced in cities that were more dependent on traditional fossil fuel energy sources and had more developed fiscal and financial levels.Studying the impact of smart city construction on energy utilization efficiency in developing countries,such as China,is not only significantly enlightening for China’s green and low-carbon transition but also provides reference opinions for constructing smart cities and the path to enhancing energy efficiency in other developing countries.The findings provide valuable insights into the global development of smart cities,urban sustainability,and high-quality economic growth. 展开更多
关键词 Smart city project Energy efficiency Legislation on environment and energy Technological innovation capabilities Green total factor productivity DIFFERENCE-IN-DIFFERENCES
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Injection-production parameters optimization research SAGD production stage
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作者 Fu Yu Qu Wenchi Song Xin 《International Journal of Technology Management》 2014年第9期119-120,共2页
Steam assisted gravity drainage (SAGD) technology has been industrialized popularization and application in our country, according to the characteristics of Xing group I SAGD experimental zone in liaohe oilfield, SA... Steam assisted gravity drainage (SAGD) technology has been industrialized popularization and application in our country, according to the characteristics of Xing group I SAGD experimental zone in liaohe oilfield, SAGD production stage injection-production parameters such as the operating pressure, Sub - Cool control, steam injection rate, steam dryness, production factor are studied and selected. 展开更多
关键词 Injection-production parameters PRESSURE steam injection rate steam quality production factor
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Agricultural Policy, Climate Factors and Grain Output: Evidence From Household Survey Data in Rural China 被引量:15
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作者 CHEN Yong-fu WU Zhi-gang +3 位作者 ZHU Tie-hui YANG Lei MAGuo-ying Chien Hsiao-ping 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第1期169-183,共15页
This paper estimates a stochastic frontier function using a panel data set that includes 4 961 farmer households for the period of 2005-2009 to decompose the growth of grain production and the total factor productivi... This paper estimates a stochastic frontier function using a panel data set that includes 4 961 farmer households for the period of 2005-2009 to decompose the growth of grain production and the total factor productivity (TFP) growth at the farmer level. The empirical results show that the major contributor to the grain output growth for farmers is input growth and that its average contribution accounts for 60.92% of farmer’s grain production growth in the period of 2006-2009, whereas the average contributions sourced from TFP growth and residuals are only 17.30 and 21.78%, respectively. The growth of intermediate inputs is a top contributor with an average contribution of 44.46%, followed by the planted area (18.16%), investment in fixed assets (1.05%), and labor input (-2.75%), indicating that the contribution from the farmer’s input growth is mainly due to the growth of intermediate inputs and that the decline in labor inputs has become an obstacle for farmers in seeking grain output growth. Among the elements consisting of TFP growth, the contribution of technical progress is the largest (32.04%), followed by grain subsidies (8.55%), the average monthly temperature (4.26%), the average monthly precipitation (-0.88%), the adjusted scale effect (-5.66%), and growth in technical efficiency (-21.01%). In general, the contribution of climate factors and agricultural policy factor are positive and significant. 展开更多
关键词 decomposition of grain output growth total factor productivity (TFP) stochastic frontier production function Chinese farmer households
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Erosion and Sediment Production in Small Watershed in Purple Hilly Areas and Prevention Techniques 被引量:4
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作者 Zhang Bao-hua, He Yu-rong, Zhou Hong-yi, Zhu BoInstitute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan, China Department of Geography, Liaocheng University, Liaocheng 252059, Shandong, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03B期1041-1046,共6页
Purple Soil distributes extensively and mainly in China. Because of abundant easily weatherable parent rocks/ materials and unstable soil structure, and also influenced by parent materials, usage systems, and slope gr... Purple Soil distributes extensively and mainly in China. Because of abundant easily weatherable parent rocks/ materials and unstable soil structure, and also influenced by parent materials, usage systems, and slope gradients, erosion and sediment production of purple soils are very severe with main fashions of water erosion and gravitational erosion. Basing on observed data in small watersheds, rainfall erosivity, vegetation coverage, previous soil water content, flow and relating factors such as climate, topograph of small watershed, land usage, and soil kinds are all the influence factors of erosion and erodibility of purple soil as well as sediment production and transport in small watershed of purple hilly areas. The effective technological countermeasures of ecosystem restoration, agricultural tillage for water conservation and erosion prevention, agriculture project, and soil changing for fertility and anti-erosion were provided. 展开更多
关键词 purple soil characteristics of erosion and sediment production) influence factors prevention techniques
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Farm Production Growth in the Upper and Middle Parts of the Yellow River Basin,China,During 1980-1999 被引量:2
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作者 LI Xiang-lian LUO Yu-zhou +2 位作者 GAO Qiong DONG Suo-cheng YANG Xiu-sheng 《Agricultural Sciences in China》 CAS CSCD 2008年第3期344-355,共12页
The impact of inputs on farm production growth was evaluated by analyzing the economic data of the upper and middle parts of the Yellow River basin, China for the period of 1980-1999. Descriptive statistics were emplo... The impact of inputs on farm production growth was evaluated by analyzing the economic data of the upper and middle parts of the Yellow River basin, China for the period of 1980-1999. Descriptive statistics were employed to characterize the temporal trends and spatial patterns in farm production and five pertinent inputs of cultivated cropland, irrigation ratio, agricultural labor, machinery power and chemical fertilizer. Stochastic frontier production function was applied to quantify the dependence of the farm production on these inputs. The growth of farm production was decomposed to reflect the contributions by input growths and change in total factor productivity.. The change in total factor productivity was further decomposed into the changes in technology and in technical efficiency. The gross value of farm production in the region of study increased by 1.6 fold during 1980-1999. Among the five selected farm inputs, machinery power and chemical fertilizer increased by 1.8 and 2.8 fold, respectively. The increases in cultivated cropland, irrigated cropland, and agricultural labor were all less than 0.16 fold. The growth in the farm production was primarily contributed by the increase in the total factor productivity during 1980-1985, and by input growths after 1985. More than 80% of the contributions by input growths were attributed to the increased application of fertilizer and machinery. In the change of total factor productivity, the technology change dominated over the technical efficiency change in the study period except in the period of 1985-1990, implying that institution and investment played important roles in farm production growth. There was a decreasing trend in the technical efficiency in the region of study, indicating a potential to increase farm production by improving the technical efficiency in farm activities. Given the limited natural resources in the basin, the results of this study suggested that, for a sustainable growth of farm production in the area, efforts should be directed to technology progress and improvement in technical efficiency in the use of available resources. 展开更多
关键词 farm production stochastic frontier production function total factor productivity upper and middle parts of the Yellow River basin
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Beta-nerve growth factor promotes neurogenesis and angiogenesis during the repair of bone defects 被引量:9
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作者 Wei-hui Chen Chuan-qing Mao +1 位作者 Li-li Zhuo Joo L.Ong 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第7期1159-1165,共7页
We previously showed that the repair of bone defects is regulated by neural and vascular signals. In the present study, we examined the effect of topically applied β-nerve growth factor(β-NGF) on neurogenesis and ... We previously showed that the repair of bone defects is regulated by neural and vascular signals. In the present study, we examined the effect of topically applied β-nerve growth factor(β-NGF) on neurogenesis and angiogenesis in critical-sized bone defects filled with collagen bone substitute. We created two symmetrical defects, 2.5 mm in diameter, on either side of the parietal bone of the skull, and filled them with bone substitute. Subcutaneously implanted osmotic pumps were used to infuse 10 μgβ-NGF in PBS(β-NGF + PBS) into the right-hand side defect, and PBS into the left(control) defect, over the 7 days following surgery. Immunohistochemical staining and hematoxylin-eosin staining were carried out at 3, 7, 14, 21 and 28 days postoperatively. On day 7, expression of β III-tubulin was lower on the β-NGF + PBS side than on the control side, and that of neurofilament 160 was greater. On day 14, β III-tubulin and protein gene product 9.5 were greater on the β-NGF + PBS side than on the control side. Vascular endothelial growth factor expression was greater on the experimental side than the control side at 7 days, and vascular endothelial growth factor receptor 2 expression was elevated on days 14 and 21, but lower than control levels on day 28. However, no difference in the number of blood vessels was observed between sides. Our results indicate that topical application of β-NGF promoted neurogenesis, and may modulate angiogenesis by promoting nerve regeneration in collagen bone substitute-filled defects. 展开更多
关键词 nerve regeneration β-nerve growth factor collagen angiogenesis protein gene product 9.5 vascular endothelial growth factor β III-tubulin neural regeneration
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Changes in Total Factor Productivity,Technological Progress and Efficiency of Banana Industry in China 被引量:2
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作者 Fang WANG Qinghe HUAN +2 位作者 Youpeng KE Jianchun GUO Qiudong LIU 《Asian Agricultural Research》 2017年第8期19-23,30,共6页
Based on the DEA-based Malmquist index method,the total factor productivity was calculated for 5 major banana production areas in 2003-2004,and it was further divided into technological progress and technical efficien... Based on the DEA-based Malmquist index method,the total factor productivity was calculated for 5 major banana production areas in 2003-2004,and it was further divided into technological progress and technical efficiency.The results show that the total factor productivity of banana industry in China was 1.3% in the sample period,mainly due to technological progress,the average growth rate was 2.6%,while the pure technical efficiency and scale efficiency was -0.1% and -1.2% respectively.The improvement of total factor productivity in banana industry in China relied mainly on technological progress,cultivation of new banana varieties,management of high quality cultivation,popularization and application of water conservation and fertilizer saving technology,and injury-free picking technologies.The pure technical efficiency and scale efficiency of banana production were negative,indicating that the management level of banana was not high.The effect of scale economy of this industry through agglomeration and consolidation is still to be practiced.Banana growers should promote the improvement of large scale and management level of the banana industry at the same time of promoting the technological progress. 展开更多
关键词 Banana industry Total factor productivity Technological progress Technical efficiency
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Regional Economic Efficiency and Its Influencing Factors of Beijing-Tianjin-Hebei Metropolitans in China Based on a Heterogeneity Stochastic Frontier Model 被引量:1
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作者 HUANG Xingling LIU Jianguo 《Chinese Geographical Science》 SCIE CSCD 2020年第1期30-44,共15页
Using a heterogeneity stochastic frontier model(HSFM),we empirically investigated the economic efficiency of Beijing-Tianjin-Hebei from 2003 to 2016 and its influencing factors.The key findings of the paper lie in:1)i... Using a heterogeneity stochastic frontier model(HSFM),we empirically investigated the economic efficiency of Beijing-Tianjin-Hebei from 2003 to 2016 and its influencing factors.The key findings of the paper lie in:1)in Beijing-Tianjin-Hebei,the overall economic and technological efficiency tended to increase in a wavelike manner,economic growth slowed down,and there was an obvious imbalance in economic efficiency between the different districts,counties and cities;2)the heterogeneity stochastic frontier production functions(SFPFs)of Beijing,Tianjin and Hebei were different from each other,and investment was still an important impetus of economic growth in Beijing-Tianjin-Hebei;3)economic efficiency was positively correlated with economic agglomeration,human capital,industrial structure,infrastructure,the informatization level,and institutional factors,but negatively correlated with the government role and economic opening.The following policy suggestions are offered:1)to improve regional economic efficiency and reduce the economic gap in Beijing-Tianjin-Hebei,governments must reduce their intervention in economic activities,stimulate the potentials of labor and capital,optimize the structure of human resources,and foster new demographic incentives;2)governments must guide economic factors that are reasonable throughout Beijing-Tianjin-Hebei and strengthen infrastructure construction in underdeveloped regions,thus attaining sustainable economic development;3)governments must plan overall economic growth factors of Beijing-Tianjin-Hebei and promote reasonable economic factors(e.g.,labor,resources,and innovations)across different regions,thus attaining complementary advantages between Beijing,Tianjin,and Hebei. 展开更多
关键词 economy efficiency total factor productivity(TFP) BEIJING-TIANJIN-HEBEI heterogeneity stochastic frontier model
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A stock assessment for Illex argentinus in Southwest Atlantic using an environmentally dependent surplus production model 被引量:3
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作者 WANG Jintao CHEN Xinjun +1 位作者 Kevin W.Staples CHEN Yong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第2期94-101,共8页
The southern Patagonian stock(SPS) of Argentinian shortfin squid, Illex argentinus, is an economically important squid fishery in the Southwest Atlantic. Environmental conditions in the region play an important role... The southern Patagonian stock(SPS) of Argentinian shortfin squid, Illex argentinus, is an economically important squid fishery in the Southwest Atlantic. Environmental conditions in the region play an important role in regulating the population dynamics of the I. argentinus population. This study develops an environmentally dependent surplus production(EDSP) model to evaluate the stock abundance of I. argentines during the period of 2000 to 2010. The environmental factors(favorable spawning habitat areas with sea surface temperature of 16–18°C) were assumed to be closely associated with carrying capacity(K) in the EDSP model. Deviance Information Criterion(DIC) values suggest that the estimated EDSP model with environmental factors fits the data better than a Schaefer surplus model without environmental factors under uniform and normal scenarios.The EDSP model estimated a maximum sustainable yield(MSY) from 351 600 t to 685 100 t and a biomass from 1 322 400 t to1 803 000 t. The fishing mortality coefficient of I. argentinus from 2000 to 2010 was smaller than the values of F(0.1) and F(MSY). Furthermore, the time series biomass plot of I. argentinus from 2000 to 2010 shows that the biomass of I.argentinus and this fishery were in a good state and not presently experiencing overfishing. This study suggests that the environmental conditions of the habitat should be considered within squid stock assessment and management. 展开更多
关键词 Illex argentinus stock assessment Schaefer surplus production model environmental factors Southwest Atlantic
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