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Research on Comparative Advantage and Typical Models of Circular Agriculture Economy in Eastern and Mid-China Region
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作者 周颖 周清波 甘寿文 《Agricultural Science & Technology》 CAS 2015年第11期2573-2580,共8页
Developing agricultural circular economy is the important measures of relieving the pressure on agricultural resources, preserving the ecological environment and promoting the sustainable development of agriculture an... Developing agricultural circular economy is the important measures of relieving the pressure on agricultural resources, preserving the ecological environment and promoting the sustainable development of agriculture and rural economy. Based on the idea of circulation of agricultural research as the breakthrough point, the research firstly detailed the concept and scientific connotation of circular egdculture in an all-round way and described and analyzed the advantages and conditions of the development of circular agriculture in eastern and middle regions of China from three aspects including resources endowment, conditions of economic development and industrial base conditions. Furthermore, the research analyzed the model char- actedstics and summarized the successful ex^dence to provide a reference for promoting the models with consideration of Taihu Lake Basin in South of Jiangsu, Yi- meng mountain areas in Southeast of Shandong and hills and mountains region in northwest Henan. Finally, the reseach put forward the development orientation of agricultural circular economy and countermeasures and suggestions to further enhance the level of development. 展开更多
关键词 Agricultural circular economy Comparative advantages Typical model Mid-Eastem China
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Circulation characteristics of horseshoe vortex in scour region around circular piers 被引量:3
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作者 Subhasish DAS Rajib DAS Asis MAZUMDAR 《Water Science and Engineering》 EI CAS CSCD 2013年第1期59-77,共19页
This paper presents an experimental investigation of the circulation of the horseshoe vortex system within the equilibrium scour hole at a circular pier, with the data measured by an acoustic Doppler velocimeter (ADV... This paper presents an experimental investigation of the circulation of the horseshoe vortex system within the equilibrium scour hole at a circular pier, with the data measured by an acoustic Doppler velocimeter (ADV). Velocity vector plots and vorticity contours of the flow field on the upstream plane of symmetry (y = 0 cm) and on the planes :e3 cm away from the plane of symmetry Cv = ~3 cm) are presented. The vorticity and circulation of the horseshoe vortices were determined using the forward difference technique and Stokes theorem, respectively. The results show that the magnitudes of circulations are similar on the planes y = 3 cm and y = -3 cm, which are less than those on the plane y = 0 cm. The circulation decreases with the increase of flow shallowness, and increases with the densimetric Froude number. It also increases with the pier Reynolds number at a constant densimetric Froude number, or at a constant flow shallowness. The relative vortex strength (dimensionless circulation) decreases with the increase of the pier Reynolds number. Some empirical equations are proposed based on the results. The predicted circulation values with these equations match the measured data, which indicates that these equations can be used to estimate the circulation in future studies. 展开更多
关键词 experimental investigation open channel turbulent flow scour horseshoe vortex "circulation circular pier forward difference technique Stokes theorem
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Comprehensive Assessment of Regional Circular Economy Development Based on Efficiency of Resource&Environment:A Case Study of Jiangsu Province 被引量:2
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作者 Zhong Taiyang Huang Xianjin +1 位作者 Li Lulu Wang Chen 《Chinese Journal of Population,Resources and Environment》 北大核心 2006年第1期54-64,共11页
In the first,the paper gave a retrospective analysis on the comprehensive assessment of circular economic development.According to the requirement of improving resource&environment efficiency,the paper designed an... In the first,the paper gave a retrospective analysis on the comprehensive assessment of circular economic development.According to the requirement of improving resource&environment efficiency,the paper designed an analytical framework for a comprehensive assessment of regional circular economic growth,which consists of the goal,object and technical line of the comprehensive assessment of regional circular economic development.Given that,the paper discussed the criterion for choosing the assessment index,the approaches of index's weighing determination,the means of data standardization,and the reference system of assessment index value and so on.According to the framework of regional circular economic development evaluation,the paper made a comprehensive evaluation of Jiangsu Province's circular economic development.The result shows that from temporal change,Jiangsu Province's circular economic development had different stages;from the spatial comparison,there is variance among different regions,which could be divided into different types according to the spatial variance and the relation between the development of circular economy and the aggregative index number.There was a remarkable correlation between circular economic development level and GDP or the 2nd industry GDP.Finally,the?aper gives some suggestions on how to promote the development of drcular economy in Jiangsu Province. 展开更多
关键词 efficiency of resource&environment omprehensive assessment of circular economic ievelopment sustainable development Jiangsu province
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An Empirical Study on the Development of Regional Circular Economy Based on Ecological Efficiency: A Case Study of Jiangsu Province
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作者 Liu Binglin Zhang Chao +4 位作者 Wang Huan Hu Qing Dai Yihao Shen Wei Zhang Wenbo 《Meteorological and Environmental Research》 CAS 2017年第5期78-86,共9页
Based on the theory of ecological efficiency,an empirical study on ecological efficiency and its changing path in Jiangsu Province during2005-2014 was conducted,and then the relationship between economic development a... Based on the theory of ecological efficiency,an empirical study on ecological efficiency and its changing path in Jiangsu Province during2005-2014 was conducted,and then the relationship between economic development and environmental pressure in the province was discussed by decoupling analysis. Finally,the main influencing factors of changes in ecological efficiency were analyzed by grey relational analysis method. The results showed that from 2005 to 2014,the resource efficiency of each indicator in Jiangsu Province fluctuated,while the environmental efficiency of most indicators increased slightly. The comprehensive resource efficiency and environmental efficiency also fluctuated,and the fluctuation range of the comprehensive environmental efficiency was larger than that of the comprehensive resource efficiency. Seen from the temporal evolution of ecological efficiency and circulation economy development pattern in Jiangsu Province,the leaping development mode was adopted in the province.The decoupling state of economic development and environmental pressure in Jiangsu Province was unstable,and they were in a state of strong decoupling,weak decoupling and expensive recoupling in most years. According to the results of grey relational analysis,comprehensive utilization of solid waste,industrial electricity consumption,electricity consumption of the whole society,domestic energy consumption,discharge of urban domestic sewage,and production of common industrial solid waste were the main influencing factors of changes in ecological efficiency in Jiangsu Province. 展开更多
关键词 ECOLOGICAL efficiency regionAL circular ECONOMY Measurement Jiangsu PROVINCE
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Role of exosomal circular RNAs as microRNA sponges and potential targeting for suppressing hepatocellular carcinoma growth and progression 被引量:2
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作者 Nikolaos Papadopoulos Eleni-Myrto Trifylli 《World Journal of Gastroenterology》 SCIE CAS 2024年第9期994-998,共5页
In this editorial,we comment on the article by Lyu et al published in the recent issue of the World Journal of Gastroenterology(2023;2219-2840).Hepatocellular carcinoma(HCC)is a frequently encountered and highly aggre... In this editorial,we comment on the article by Lyu et al published in the recent issue of the World Journal of Gastroenterology(2023;2219-2840).Hepatocellular carcinoma(HCC)is a frequently encountered and highly aggressive primary liver cancer,which remains the third-commonest cause of cancer-related death despite the current therapeutic modalities.There is urgency in developing novel thera-peutic approaches,such as by manipulating extracellular vesicles,which con-stitute a highly heterogeneous nanoparticle population that contains various cargoes.These cargoes have a pivotal role in cell-to-cell communication and can modify the functional level of the recipient cells via their uptake by other recipient cells.Exosomal non-coding RNAs have particular evolving significance in HCC,such as circular RNAs,which have been found differentially expressed in normal hepatic and HCC tissues.The aberrations in their expression levels have a key role in the HCC development and progression and the overall prognosis.In this editorial,we will shed light on the emerging role of exosomal circular RNAs in HCC development and progression,focusing on the oncogenic or potentially tumor suppressive effect of mesenchymal stem cells-derived exosomal non-coding RNAs. 展开更多
关键词 circular SPONGE PROGRESSION
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Challenges and Path of Developing Circular Economy at Regional Level——A Case Study of Anhui Province
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作者 SHAO Hui1,CHEN Hong-feng2 1.School of Economics and Resource Management,Beijing Normal University,Beijing 100875,China 2.Anhui Academy of Environmental Sciences Research,Hefei 230061,China 《Asian Agricultural Research》 2011年第9期15-20,共6页
Existing foundation and development opportunities of regional circular economy are elaborated.The first is gradual establishment and perfection of relevant laws and regulations and policy systems.The second is establi... Existing foundation and development opportunities of regional circular economy are elaborated.The first is gradual establishment and perfection of relevant laws and regulations and policy systems.The second is establishment of technical standard for circular economy and implementation of development model.The third is scientific and technical innovation providing technical support for circular economy.The fourth is opportunity of green development in international environmental and economic situations.And the fifth is leap-style development supported by solid foundation.Then,Anhui Province is taken as an example to analyze challenges faced by circular economy.The challenges include increase of resource restriction and environment pressure;supporting policy and legal system to be further perfected and implemented;circular economic indicators not included into political achievement assessment;and technical supporting foundation of circular economy still to be strengthened.Finally,path selection is put forward for development of circular economy in Anhui Province:make definite development direction of circular economy with tasks and targets;take major fields as carriers of development of circular economy;take major fields as carriers of development of circular economy;and take institutional construction as guarantee of circular economic development. 展开更多
关键词 circular ECONOMY PATH selection SCIENTIFIC and TEC
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Does digitalization mitigate regional inequalities?Evidence from China 被引量:1
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作者 Haimeng Liu Xinyang Wang +1 位作者 Zheye Wang Yu Cheng 《Geography and Sustainability》 CSCD 2024年第1期52-63,共12页
Regional inequality significantly influences sustainable development and human well-being.In China,there exists pronounced regional disparities in economic and digital advancements;however,scant research delves into t... Regional inequality significantly influences sustainable development and human well-being.In China,there exists pronounced regional disparities in economic and digital advancements;however,scant research delves into the interplay between them.By analyzing the economic development and digitalization gaps at regional and city levels in China,extending the original Cobb-Douglas production function,this study aims to evaluate the impact of digitalization on China's regional inequality using seemingly unrelated regression.The results indicate a greater emphasis on digital inequality compared to economic disparity,with variable coefficients of 0.59 for GDP per capita and 0.92 for the digitalization index over the past four years.However,GDP per capita demonstrates higher spatial concentration than digitalization.Notably,both disparities have shown a gradual reduction in recent years.The southeastern region of the Hu Huanyong Line exhibits superior levels and rates of economic and digital advancement in contrast to the northwestern region.While digitalization propels economic growth,it yields a nuanced impact on achieving balanced regional development,encompassing both positive and negative facets.Our study highlights that the marginal utility of advancing digitalization is more pronounced in less developed regions,but only if the government invests in the digital infrastructure and education in these areas.This study's methodology can be utilized for subsequent research,and our findings hold the potential to the government's regional investment and policy-making. 展开更多
关键词 regional inequality regional disparities Digital divide DIGITALIZATION Sustainable development Economic growth Seemingly unrelated regression
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Construction and Application of a Regional Kilometer-Scale Carbon Source and Sink Assimilation Inversion System(CCMVS-R) 被引量:2
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作者 Lifeng Guo Xiaoye Zhang +8 位作者 Junting Zhong Deying Wang Changhong Miao Licheng Zhao Zijiang Zhou Jie Liao Bo Hu Lingyun Zhu Yan Chen 《Engineering》 SCIE EI CAS CSCD 2024年第2期263-275,共13页
CO_(2)is one of the most important greenhouse gases(GHGs)in the earth’s atmosphere.Since the industrial era,anthropogenic activities have emitted excessive quantities of GHGs into the atmosphere,resulting in climate ... CO_(2)is one of the most important greenhouse gases(GHGs)in the earth’s atmosphere.Since the industrial era,anthropogenic activities have emitted excessive quantities of GHGs into the atmosphere,resulting in climate warming since the 1950s and leading to an increased frequency of extreme weather and climate events.In 2020,China committed to striving for carbon neutrality by 2060.This commitment and China’s consequent actions will result in significant changes in global and regional anthropogenic carbon emissions and therefore require timely,comprehensive,and objective monitoring and verification support(MVS)systems.The MVS approach relies on the top-down assimilation and inversion of atmospheric CO_(2)concentrations,as recommended by the Intergovernmental Panel on Climate Change(IPCC)Inventory Guidelines in 2019.However,the regional high-resolution assimilation and inversion method is still in its initial stage of development.Here,we have constructed an inverse system for carbon sources and sinks at the kilometer level by coupling proper orthogonal decomposition(POD)with four-dimensional variational(4DVar)data assimilation based on the weather research and forecasting-greenhouse gas(WRF-GHG)model.Our China Carbon Monito ring and Verification Support at the Regional level(CCMVS-R)system can continuously assimilate information on atmospheric CO_(2)and other related information and realize the inversion of regional and local anthropogenic carbon emissions and natural terrestrial ecosystem carbon exchange.Atmospheric CO_(2)data were collected from six ground-based monito ring sites in Shanxi Province,China to verify the inversion effect of regio nal anthropogenic carbon emissions by setting ideal and real experiments using a two-layer nesting method(at 27 and 9 km).The uncertainty of the simulated atmospheric CO_(2)decreased significantly,with a root-mean-square error of CO_(2)concentration values between the ideal value and the simulated after assimilation was close to 0.The total anthropogenic carbon emissions in Shanxi Province in 2019 from the assimilated inversions were approximately 28.6%(17%-38%)higher than the mean of five emission inventories using the bottomup method,showing that the top-down CCMVS-R system can obtain more comprehensive information on anthropogenic carbon emissions. 展开更多
关键词 CCMVS-R regional carbon assimilation system Anthropogenic carbon emissions CO_(2) POD 4DVar
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Circular economy indicators to evaluate regional development: A case study of Tianjin municipality
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作者 SHEN Cheng-lin QIN Rui-qi 《Chinese Business Review》 2007年第4期15-19,共5页
With the aim of the harmonious development of economy-environment system in Tianjin Municipality, an index system used to evaluate the circular economy (CE) is presented in this paper. The index system consists of t... With the aim of the harmonious development of economy-environment system in Tianjin Municipality, an index system used to evaluate the circular economy (CE) is presented in this paper. The index system consists of the index of economy development, green development, human and culture development. According to the evaluation results, this paper brings forward the countermeasures including industry structure adjustment, improving city infrastructure system, increasing the level of habitation environment, establishing the system of green social consumption to improve the development of circular economy in Tianjin. 展开更多
关键词 circular economy evaluation index system Tianjin municipality
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A core-satellite self-assembled SERS aptasensor containing a“biological-silent region”Raman tag for the accurate and ultrasensitive detection of histamine 被引量:1
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作者 Chen Chen Yingfang Zhang +3 位作者 Ximo Wang Xuguang Qiao Geoffrey I.N.Waterhouse Zhixiang Xu 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期1029-1039,共11页
Herein,a novel interference-free surface-enhanced Raman spectroscopy(SERS)strategy based on magnetic nanoparticles(MNPs)and aptamer-driven assemblies was proposed for the ultrasensitive detection of histamine.A core-s... Herein,a novel interference-free surface-enhanced Raman spectroscopy(SERS)strategy based on magnetic nanoparticles(MNPs)and aptamer-driven assemblies was proposed for the ultrasensitive detection of histamine.A core-satellite SERS aptasensor was constructed by combining aptamer-decorated Fe_(3)O_(4)@Au MNPs(as the recognize probe for histamine)and complementary DNA-modified silver nanoparticles carrying 4-mercaptobenzonitrile(4-MBN)(Ag@4-MBN@Ag-c-DNA)as the SERS signal probe for the indirect detection of histamine.Under an applied magnetic field in the absence of histamine,the assembly gave an intense Raman signal at“Raman biological-silent”region due to 4-MBN.In the presence of histamine,the Ag@4-MBN@Ag-c-DNA SERS-tag was released from the Fe_(3)O_(4)@Au MNPs,thus decreasing the SERS signal.Under optimal conditions,an ultra-low limit of detection of 0.65×10^(-3)ng/mL and a linear range 10^(-2)-10^5 ng/mL on the SERS aptasensor were obtained.The histamine content in four food samples were analyzed using the SERS aptasensor,with the results consistent with those determined by high performance liquid chromatography.The present work highlights the merits of indirect strategies for the ultrasensitive and highly selective SERS detection of small biological molecules in complex matrices. 展开更多
关键词 Surface-enhanced Raman spectroscopy Raman biological-silent region APTAMER Histamine detection Universal SERS-tag
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Organic Matter Accumulation in the Upper Permian Dalong Formation from the Lower Yangtze Region,South China 被引量:1
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作者 FANG Chaogang ZHANG Chengcheng +5 位作者 MENG Guixi XU Jinlong XU Naicen LI Hualing LIU Mu LIU Bo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期150-167,共18页
The Late Permian was marked by a series of important geological events and widespread organic-rich black shale depositions,acting as important unconventional hydrocarbon source rocks.However,the mechanism of organic m... The Late Permian was marked by a series of important geological events and widespread organic-rich black shale depositions,acting as important unconventional hydrocarbon source rocks.However,the mechanism of organic matter(OM)enrichment throughout this period is still controversial.Based on geochemical data,the marine redox conditions,paleogeographic and hydrographic environment,primary productivity,volcanism,and terrigenous input during the Late Permian in the Lower Yangtze region have been studied from the Putaoling section,Chaohu,to provide new insights into OM accumulation.Five Phases are distinguished based on the TOC and environmental variations.In Phase I,anoxic conditions driven by water restriction enhanced OM preservation.In Phase II,euxinic and cycling hydrological environments were the two most substantial controlling factors for the massive OM deposition.During Phase III,intensified terrestrial input potentially diluted the OM in sediment and the presence of oxygen in bottom water weakened the preservation condition.Phase IV was characterized by a relatively higher abundance of mercury(Hg)and TOC(peak at 16.98 wt%),indicating that enhanced volcanism potentially stimulated higher productivity and a euxinic environment.In Phase V,extremely lean OM was preserved as a result of terrestrial dilutions and decreasing primary productivity.Phases I,II and IV are characterized as the most prominent OM-rich zones due to the effective interactions of the controlling factors,namely paleogeographic,hydrographic environment,volcanism,and redox conditions. 展开更多
关键词 GEOCHEMISTRY redox condition primary productivity OM accumulation Lopingian/Changhsingian Lower Yangtze region
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Diagnostic Study of an Extreme Explosive Cyclone over the Kuroshio/Kuroshio Extension Region 被引量:1
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作者 ZHANG Shuqin LIAO Qinghua +4 位作者 LIU Chunlei GAO Xiaoyu LONG Jingchao LI Pengyuan XU Jianjun 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期605-617,共13页
Explosive cyclones(ECs)occur frequently over the Kuroshio/Kuroshio Extension region.The most rapidly intensified EC over the Kuroshio/Kuroshio Extension region during the 42 years(1979-2020)of cold seasons(October-Apr... Explosive cyclones(ECs)occur frequently over the Kuroshio/Kuroshio Extension region.The most rapidly intensified EC over the Kuroshio/Kuroshio Extension region during the 42 years(1979-2020)of cold seasons(October-April)was studied to reveal the variations of the key factors at different explosive-developing stages.This EC had weak low-level baroclinicity,mid-level cyclonic-vorticity advection,and strong low-level water vapor convergence at the initial explosive-developing stage.The low-level baroclinicity and mid-level cyclonic-vorticity advection increased substantially during the maximum-deepening-rate stage.The diagnostic analyses using the Zwack-Okossi equation showed that diabatic heating was the main contributor to the initial rapid intensification of this EC.The cyclonic-vorticity advection and warm-air advection enhanced rapidly in the middle and upper troposphere and contributed to the maximum rapid intensification,whereas the diabatic heating weakened slightly in the mid-low troposphere.The relative contribution of the diabatic heating decreased from the initial explosive-developing stage to the maximum-deepening-rate stage due to the enhancement of other factors(the cyclonic-vorticity advection and warm-air advection).Furthermore,the physical factors contributing to this EC varied with the explosive-developing stage.The non-key factors at the initial explosive-developing stage need attention to forecast the rapid intensification. 展开更多
关键词 explosive cyclone diabatic heating cyclonic-vorticity advection rapid intensification the Kuroshio/Kuroshio Extension region
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Interdecadal variability of summer precipitation in the Three River Source Region: Influences of SST and zonal shifts of the East Asian subtropical westerly jet 被引量:1
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作者 Yumeng Liu Xianhong Meng +5 位作者 Lin Zhao S-Y.Simon Wang Lixia Zhang Zhaoguo Li Chan Wang Yingying An 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期47-53,共7页
Summer precipitation in the Three Rivers Source Region(TRSR)of China is vital for the headwaters of the Yellow,Yangtze,and Lancang rivers and exhibits significant interdecadal variability.This study investigates the i... Summer precipitation in the Three Rivers Source Region(TRSR)of China is vital for the headwaters of the Yellow,Yangtze,and Lancang rivers and exhibits significant interdecadal variability.This study investigates the influence of the East Asian westerly jet(EAWJ)on TRSR rainfall.A strong correlation is found between TRSR summer precipitation and the Jet Zonal Position Index(JZPI)of the EAWJ from 1961 to 2019(R=0.619,p<0.01).During periods when a positive JZPI indicates a westward shift in the EAWJ,enhanced water vapor anomalies,warmer air,and low-level convergence anomalies contribute to increased TRSR summer precipitation.Using empirical orthogonal function and regression analyses,this research identifies the influence of large-scale circulation anomalies associated with the Atlantic–Eurasian teleconnection(AEA)from the North Atlantic(NA).The interdecadal variability between the NA and central tropical Pacific(CTP)significantly affects TRSR precipitation.This influence is mediated through the AEA via a Rossby wave train extending eastward along the EAWJ,and another south of 45°N.Moreover,the NA–CTP Opposite Phase Index(OPI),which quantifies the difference between the summer mean sea surface temperatures of the NA and the CTP,is identified as a critical factor in modulating the strength of this teleconnection and influencing the zonal position of the EAWJ. 展开更多
关键词 Summer precipitation East Asian subtropical westerly jet Three River Source region Atlantic-Eurasian teleconnection
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Regional economic assessment of a novel place-based model for sustainable food systems
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作者 Susanna Kujala Kari Koppelmäki 《Geography and Sustainability》 CSCD 2024年第2期220-229,共10页
Several actions from both the environmental and human viewpoints have already been made to meet the sustainability goals targeted at food systems.Still,new place-based ideas to improve sustainability are needed.Agroec... Several actions from both the environmental and human viewpoints have already been made to meet the sustainability goals targeted at food systems.Still,new place-based ideas to improve sustainability are needed.Agroecological symbiosis(AES),a novel food system model,is an example of a suggested system-level change to attain sustainability targets;it is a symbiosis of food production and processing using renewable energy that uses its own feedstock.AES has already been found advantageous from the ecological and biophysical viewpoints,but a regional economic evaluation of the model is still lacking.Thus,the aim of our paper is to assess the regional economic impact of a possible systemic change in the food system using the network of agroecological symbiosis(NAES)as an example.We applied scenarios representing different ways of moving towards envisioned NAES models in Mäntsälä,Finland,and a computable general equilibrium model to evaluate the regional economic impact.According to our results,both regional economy and employment would increase,and the regional production base would diversify with NAES implementation applied to the region,but the extent of the benefits varies between scenarios.The scenario that includes change in both public and private food demand,production of bioenergy and utilization of by-products would cause the largest impacts.However,realizing NAES requires investments that may influence the actual implementation of such models.Nonetheless,a change towards NAES can promote an economically and spatially just transition to sustainability,as NAES seems to be economically most beneficial for rural areas. 展开更多
关键词 SUSTAINABILITY regional economy Localized food system Renewable energy circularITY
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Dynamic response characteristics of a circular lined tunnel under anisotropy frost heave of overlying soil at the tunnel portal section in cold regions
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作者 ZHANG Shuo-cheng CHEN Wen-hua 《Journal of Mountain Science》 SCIE CSCD 2023年第5期1424-1440,共17页
The rapid development of traffic engineering in cold regions and its consequent problems need to be considered.In this paper,the dynamic response characteristics of the tunnel portal section in cold regions with harmo... The rapid development of traffic engineering in cold regions and its consequent problems need to be considered.In this paper,the dynamic response characteristics of the tunnel portal section in cold regions with harmonic load acting on the lining were studied in the frequency domain.The lining is in close contact with the frozen soil,and there is relative movement between the frozen and unfrozen soil due to the phase change.The analytical solution of the vibration of tunnel portal section caused by the harmonic load acting on the lining was derived under the consideration of the anisotropy frost heave of overlying soil.Based on the continuity conditions and boundary conditions,the undetermined coefficients were obtained,and the analytical solutions for different medium displacements and stresses of the cold-region tunnel system were acquired.The vertical pressure coefficient was equivalently simplified as a variable that could be used to replace the thickness of the overlying soil above the tunnel.The analysis of the parameter model shows that the change of the medium parameters(lining,frozen,and unfrozen soil)affects the circumferential stresses,the radial displacements and their peak frequencies of the soil.For example,the increase of density ratio of tunnel lining to frozen soil decreases the radial stresses of the frozen and unfrozen soil;the increase of volumetric frost heaving strain of the frozen soil increases the radial displacements of the frozen surface and decreases the stability of the frozen surface;the increasing of thickness of the frozen soil significantly reduces the radial displacement of unfrozen soil at dimensionless radius η=4.5 compared with that of frozen soil at η=1.5. 展开更多
关键词 Frost heave Tunnel portal section Relative movement Dynamic response characteristics Cold region
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Evaluation of Industrial IoT Service Providers with TOPSIS Based on Circular Intuitionistic Fuzzy Sets
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作者 Elif Çalo˘glu Büyükselçuk 《Computers, Materials & Continua》 SCIE EI 2024年第7期715-746,共32页
Industrial Internet of Things(IIoT)service providers have become increasingly important in the manufacturing industry due to their ability to gather and process vast amounts of data from connected devices,enabling man... Industrial Internet of Things(IIoT)service providers have become increasingly important in the manufacturing industry due to their ability to gather and process vast amounts of data from connected devices,enabling manufacturers to improve operational efficiency,reduce costs,and enhance product quality.These platforms provide manufacturers with real-time visibility into their production processes and supply chains,allowing them to optimize operations and make informed decisions.In addition,IIoT service providers can help manufacturers create new revenue streams through the development of innovative products and services and enable them to leverage the benefits of emerging technologies such as Artificial Intelligence(AI)and machine learning.Overall,the implementation of IIoT platforms in the manufacturing industry is crucial for companies seeking to remain competitive and meet the ever-increasing demands of customers in the digital age.In this study,the evaluation criteria to be considered in the selection of IIoT service provider in small andmedium-sized(SME)manufacturing enterprises will be determined and IIoT service providers alternatives will be evaluated using the technique for order preference by similarity to an ideal solution(TOPSIS)method based on circular intuitionistic fuzzy sets.Based on the assessments conducted in accordance with the literature review and expert consultations,a set of 8 selection criteria has been established.These criteria encompass industry expertise,customer support,flexibility and scalability,security,cost-effectiveness,reliability,data analytics,as well as compatibility and usability.Upon evaluating these criteria,it was observed that the security criterion holds the highest significance,succeeded by cost-effectiveness,data analytics,flexibility and scalability,reliability,and customer support criteria,in descending order of importance.Following the evaluation of seven distinct alternatives against these criteria,it was deduced that the A6 alternative,a German service provider,emerged as the most favorable option.The identical issue was addressed utilizing sensitivity analysis alongside various multi-criteria decision-making(MCDM)methods,and after comprehensive evaluation,the outcomes were assessed.Spearman’s correlation coefficient was computed to ascertain the association between the rankings derived from solving the problem using diverse MCDM methods. 展开更多
关键词 IIoT MANUFACTURING TOPSIS circular intuitionistic fuzzy sets
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On the spreading behavior of a droplet on a circular cylinder using the lattice Boltzmann method
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作者 杨帆 金虎 戴梦瑶 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期434-443,共10页
The study of a droplet spreading on a circular cylinder under gravity was carried out using the pseudo-potential lattice Boltzmann high-density ratios multiphase model with a non-ideal Peng–Robinson equation of state... The study of a droplet spreading on a circular cylinder under gravity was carried out using the pseudo-potential lattice Boltzmann high-density ratios multiphase model with a non-ideal Peng–Robinson equation of state. The calculation results indicate that the motion of the droplet on the cylinder can be divided into three stages: spreading, sliding, and aggregating.The contact length and contact time of a droplet on a cylindrical surface can be affected by factors such as the wettability gradient of the cylindrical wall, the Bond number, and droplet size. Furthermore, phase diagrams showing the relationship between Bond number, cylinder wall wettability gradient, and contact time as well as maximum contact length for three different droplet sizes are given. A theoretical foundation for additional research into the heat and mass transfer process between the droplet and the cylinder can be established by comprehending the variable rules of maximum contact length and contact time. 展开更多
关键词 lattice Boltzmann methods DROPLET circular cylinder wettability gradient
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Assessment of plant diversity of endemic species of the Saharo-Arabian region in Egypt
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作者 Asmaa S ABO HATAB Yassin M AL-SODANY +2 位作者 Kamal H SHALTOUT Soliman A HAROUN Mohamed M EL-KHALAFY 《Journal of Arid Land》 SCIE CSCD 2024年第7期1000-1021,I0002-I0044,共65页
Savanna, semi-deserts, and hot deserts characterize the Saharo-Arabian region, which includes Morocco, Mauretania, Algeria, Tunisia, Libya, Egypt, Palestine, Kuwait, Saudi Arabia, Qatar, Bahrain, the United Arab Emira... Savanna, semi-deserts, and hot deserts characterize the Saharo-Arabian region, which includes Morocco, Mauretania, Algeria, Tunisia, Libya, Egypt, Palestine, Kuwait, Saudi Arabia, Qatar, Bahrain, the United Arab Emirates, Oman, Yemen, southern Jordan, Syria, Iraq, Iran, Afghanistan, Pakistan, and northern India. Its neighboring regions, the Sudano-Zambezian region belonging to the Paleotropical Kingdom and the Mediterranean and Irano-Turanian regions included in the Holarctic Kingdom, share a large portion of their flora with the Saharo-Arabian region. Despite the widespread acknowledgment of the region's global importance for plant diversity, an up to date list of the Saharo-Arabian endemics is still unavailable. The available data are frequently insufficient or out of date at both the whole global and the national scales. Therefore, the present study aims at screening and verifying the Saharo-Arabian endemic plants and determining the phytogeographical distribution of these taxa in the Egyptian flora. Hence, a preliminary list of 429 Saharo-Arabian endemic plants in Egypt was compiled from the available literature. Indeed, by excluding the species that were recorded in any countries or regions outside the Saharo-Arabian region based on different literature, database reviews, and websites, the present study has reduced this number to 126 taxa belonging to 87 genera and 37 families. Regarding the national geographic distribution, South Sinai is the richest region with 83 endemic species compared with other eight phytogeographic regions in Egypt, followed by the Isthmic Desert(the middle of Sinai Peninsula, 53 taxa). Sahara regional subzone(SS1) distributes all the 126 endemic species, Arabian regional subzone(SS2) owns 79 taxa, and Nubo-Sindian subzone(SS3) distributes only 14 endemics. Seven groups were recognized at the fourth level of classification as a result of the application of the two-way indicator species analysis(TWINSPAN) to the Saharo-Arabian endemic species in Egypt, i.e., Ⅰ Asphodelus refractus group, Ⅱ Agathophora alopecuroides var. papillosa group, Ⅲ Anvillea garcinii group, Ⅳ Reseda muricata group, V Agathophora alopecuroides var. alopecuroides group, Ⅵ Scrophularia deserti group, and Ⅶ Astragalus schimperi group. It's crucial to clearly define the Saharo-Arabian endemics and illustrate an updated verified database of these taxa for a given territory for providing future management plans that support the conservation and sustainable use of these valuable species under current thought-provoking devastating impacts of rapid anthropogenic and climate change in this region. 展开更多
关键词 ENDEMISM phytogeographical regions Saharo-Arabian floristic region Egyptian flora plant diversity two-way indicator species analysis(TWINSPAN)
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Effect of Mushroom Extract Hericium erinaceus on Spatial Memory and Morphology of Neurons in the CA1 and CA3 Regions of the Hippocampus in Ovariectomized Rats
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作者 Lucia Garcia-Delgado Mariana Monserrath Verdía-Venegas +5 位作者 Jacinto Bañuelos-Pineda Esther Albarrán-Rodríguez Guillermo Nolasco-Rodriguez José Ricardo Cuellar-Pérez Sergio Fausto-Guerra Manuel Rosales-Cortés 《Open Journal of Veterinary Medicine》 CAS 2024年第7期163-179,共17页
Various studies indicate that low levels of estradiol negatively impact cognitive abilities. Extracts from the fungus Hericium erinaceus (HE) contain bioactive components that promote the proper functioning of the ner... Various studies indicate that low levels of estradiol negatively impact cognitive abilities. Extracts from the fungus Hericium erinaceus (HE) contain bioactive components that promote the proper functioning of the nervous system and potential effects on protection against neurodegenerative diseases, including dementia and motor dysfunctions. The objective was to evaluate the effects of the administration of the HE mushroom extract on visuospatial memory and morphology of neurons in the CA1 and CA3 regions of the hippocampus in ovariectomized rats. 40 young Wistar rats weighing 90 ± 10 g BW were used, which were distributed into four groups of 10 animals;Control Group, non-ovariectomized and untreated rats;Group E2, ovariectomized rats treated with estradiol (2 μg/kg/body weight);Group HE, ovariectomized rats treated with the extract of the fungus Hericium erinaceus (0.5 mg/kg body weight) and Group Ovx/ST, ovariectomized rats, without treatment. The animals were tested in the Barnes and Open Field maze, then they were sacrificed, and their brains were obtained to perform a histological analysis of neuronal morphology in the CA1 and CA3 areas of the hippocampus. The most outstanding results showed that the Ovx/ST group recorded the longest time to arrive at the escape box and stay in the Barnes maze. A correlation was observed between neuronal damage and function;in the groups that did not present satisfactory performance in the maze tests, morphological alterations were identified such as the presence of some neuronal somata with degeneration characteristics such as pyknosis, nuclear basophilia and shrinkage of the cells. Its soma, as well as a decrease in the nuclear area of CA1 and CA3 neurons. It is concluded that the fungus Hericium erinaceus exerted a neuroprotective effect on the neuronal bodies of the hippocampus, associated with better performance in the visuospatial recognition memory test. 展开更多
关键词 Ovariectomized Rats Ovarian Hypofunction ESTRADIOL Hericium erinaceus Barnes circular Labyrinth Open Field Labyrinth
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Investigation of Groundwater Quality with Borehole Depth in the Basin Granitoids of the Ashanti Region of Ghana
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作者 Bernard Ofosu Augustine Kofi Asante +2 位作者 Festus Anane Mensah Umar-Farouk Usman Naa Korkoi Ayeh 《Journal of Water Resource and Protection》 CAS 2024年第5期381-394,共14页
The dependence of groundwater quality on borehole depth is usually debatable in groundwater studies, especially in complex geological formations where aquifer characteristics vary spatially with depth. This study ther... The dependence of groundwater quality on borehole depth is usually debatable in groundwater studies, especially in complex geological formations where aquifer characteristics vary spatially with depth. This study therefore seeks to investigate the relationship between borehole depth and groundwater quality across the granitoid aquifers within the Birimian Supergroup in the Ashanti Region. Physicochemical analysis records of groundwater quality data were collected from 23 boreholes of public and private institutions in the Ashanti Region of Ghana, and the parametric values of iron, fluoride, total hardness, pH, nitrate, and nitrite were used to study the groundwater quality-depth relationship. The results showed that the depth-to-groundwater quality indicated a marginal increase in water quality in the range of 30 to 50 m, which is mathematically represented by the low-value correlation coefficient (r<sup>2</sup> = 0.026). A relatively significant increase occurs in the depth range of 50 to 80 m, which is given by a correlation coefficient of r<sup>2</sup> = 0.298. The mean percent parameter compatibility was 74%, 82%, 89%, and 97% at 50, 60, 70, and 80 m depths, respectively. The variations in groundwater quality per depth ratio ranged from 1.48, 1.37, 1.27, and 1.21 for 50, 60, 70, and 80 m depth, respectively. The recommended minimum borehole depth for excellent groundwater quality is suggested with a compatibility per meter depth ratio of 1.37. This results in a range between 50 and 70 m as the most desirable drilling depth for excellent groundwater quality within the granitoids of the Birimian Supergroup of the Ashanti Region in Ghana. 展开更多
关键词 Groundwater Quality Borehole Depth Birimian Supergroup Granitoid Aquifers Ashanti region
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