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The multiple roles of crop structural change in productivity,nutrition and environment in China:A decomposition analysis
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作者 Xiangyang Zhang Yumei Zhang Shenggen Fan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1763-1773,共11页
China's crop structure has undergone significant changes in the last two decades since 2000,with an increase in the share of cereals,vegetables,and fruit,squeezing out other crops.As a result,land productivity,nut... China's crop structure has undergone significant changes in the last two decades since 2000,with an increase in the share of cereals,vegetables,and fruit,squeezing out other crops.As a result,land productivity,nutrient supply,and carbon emissions have changed.How to reallocate limited farmland among crops to achieve the multiple goals of agrifood systems becomes an important issue.This study explores the sources of land productivity and nutrition supply growth and carbon emissions reduction,and identifies the multiple roles of crop structural change from 2003 to 2020 based on a decomposition analysis.The results reveal that the growth within crops is still the primary driver in land productivity and nutrition supply and the reduction in carbon emissions.However,structural change also plays various roles at different periods.From 2003 to 2010,crop structural change increased the total calorie supply but lowered land productivity and contributed at least 70%of the total growth of carbon emissions.The crop structure was relatively stable,and their effects were modest from 2010 to 2015.From 2015 to 2020,the crop structural change began to play a greater role and generate synergistic effects in improving land productivity,micronutrient supply,and reducing carbon emissions,contributing to approximately a quarter of the growth of land productivity and 30%of total carbon emissions reduction.These results suggest that strategies for crop structural change should comprehensively consider its multiple impacts,aiming to achieve co-benefits while minimizing trade-offs. 展开更多
关键词 CROP structural change land productivity NUTRITION carbon emissions
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Land use and cover change and influencing factor analysis in the Shiyang River Basin,China
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作者 ZHAO Yaxuan CAO Bo +4 位作者 SHA Linwei CHENG Jinquan ZHAO Xuanru GUAN Weijin PAN Baotian 《Journal of Arid Land》 SCIE CSCD 2024年第2期246-265,共20页
Land use and cover change(LUCC)is the most direct manifestation of the interaction between anthropological activities and the natural environment on Earth's surface,with significant impacts on the environment and ... Land use and cover change(LUCC)is the most direct manifestation of the interaction between anthropological activities and the natural environment on Earth's surface,with significant impacts on the environment and social economy.Rapid economic development and climate change have resulted in significant changes in land use and cover.The Shiyang River Basin,located in the eastern part of the Hexi Corridor in China,has undergone significant climate change and LUCC over the past few decades.In this study,we used the random forest classification to obtain the land use and cover datasets of the Shiyang River Basin in 1991,1995,2000,2005,2010,2015,and 2020 based on Landsat images.We validated the land use and cover data in 2015 from the random forest classification results(this study),the high-resolution dataset of annual global land cover from 2000 to 2015(AGLC-2000-2015),the global 30 m land cover classification with a fine classification system(GLC_FCS30),and the first Landsat-derived annual China Land Cover Dataset(CLCD)against ground-truth classification results to evaluate the accuracy of the classification results in this study.Furthermore,we explored and compared the spatiotemporal patterns of LUCC in the upper,middle,and lower reaches of the Shiyang River Basin over the past 30 years,and employed the random forest importance ranking method to analyze the influencing factors of LUCC based on natural(evapotranspiration,precipitation,temperature,and surface soil moisture)and anthropogenic(nighttime light,gross domestic product(GDP),and population)factors.The results indicated that the random forest classification results for land use and cover in the Shiyang River Basin in 2015 outperformed the AGLC-2000-2015,GLC_FCS30,and CLCD datasets in both overall and partial validations.Moreover,the classification results in this study exhibited a high level of agreement with the ground truth features.From 1991 to 2020,the area of bare land exhibited a decreasing trend,with changes primarily occurring in the middle and lower reaches of the basin.The area of grassland initially decreased and then increased,with changes occurring mainly in the upper and middle reaches of the basin.In contrast,the area of cropland initially increased and then decreased,with changes occurring in the middle and lower reaches.The LUCC was influenced by both natural and anthropogenic factors.Climatic factors and population contributed significantly to LUCC,and the importance values of evapotranspiration,precipitation,temperature,and population were 22.12%,32.41%,21.89%,and 19.65%,respectively.Moreover,policy interventions also played an important role.Land use and cover in the Shiyang River Basin exhibited fluctuating changes over the past 30 years,with the ecological environment improving in the last 10 years.This suggests that governance efforts in the study area have had some effects,and the government can continue to move in this direction in the future.The findings can provide crucial insights for related research and regional sustainable development in the Shiyang River Basin and other similar arid and semi-arid areas. 展开更多
关键词 land use and cover classification land use and cover change(LUCC) climate change random forest accuracy assessment three-dimensional sampling method Shiyang River Basin
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Change Point Analysis to Detect the Effect of Pruning Severity on Tree Growth
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作者 Yutaka Iguchi 《Open Journal of Forestry》 2024年第1期67-73,共7页
The effect of pruning severity on tree growth was analyzed by change point detection using segmented regression. The present study applied this analysis to a well-known published data set including diameter growth res... The effect of pruning severity on tree growth was analyzed by change point detection using segmented regression. The present study applied this analysis to a well-known published data set including diameter growth response, tree age, pruning severity and pretreatment crown size. First, multiple regression analysis was performed to assess the effect of tree age, pruning severity and pretreatment crown size on diameter growth response. Next, segmented regression analysis was performed to assess the effect of pruning severity on diameter growth response. The results of the multiple regression showed that diameter growth response was significantly influenced by pruning severity and pretreatment crown size. The results of the segmented regression showed that in the whole data set, an abrupt change toward a decrease in diameter growth response was detected at 25% of the live crown removed. However, in the group of fully crowned and open-grown, diameter growth response continuously decreased with increasing pruning severity with no significant abrupt change, whereas in the group of 70% - 90% live crown, diameter growth response did not significantly decrease up to the break point (53% crown removed) and then abruptly decreased. This may be the first study to show the numerical evaluation of the effect of pruning severity on tree growth by change point analysis. 展开更多
关键词 Regression analysis Crown Removal Limit Tree Growth PRETREATMENT Abrupt change
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Brain Transcriptome Analysis Reveals Metabolic Changes Adapting to Hyperhaline or Hypohaline Environments in Spotted Scat(Scatophagus argus)
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作者 LIN Ting ZHAI Yi +5 位作者 TIAN Changxu JIANG Dongneng SHI Hongjuan JIANG Mouyan LI Guangli DENG Siping 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期755-765,共11页
The fish brain is crucial for adjusting to environmental changes.Metabolic changes play a vital role in the adaptation to salinity change in aquatic animals.However,few studies have evaluated the responses of the fish... The fish brain is crucial for adjusting to environmental changes.Metabolic changes play a vital role in the adaptation to salinity change in aquatic animals.However,few studies have evaluated the responses of the fish brain to salinity changes.To evaluate the response to various salinities,spotted scat(Scatophagus argus)was cultured in water with salinity levels of 5(low salinity:LS),25(control group:Ctrl),and 35(high salinity group:HS)for 22 days.The brain transcriptome was analyzed.In total,1698 differentially expressed genes(DEGs)were identified between the HS and Ctrl groups,and 841 DEGs were identified between the LS and Ctrl groups.KEGG analysis showed that the DEGs in the HS vs.Ctrl comparison were involved in steroid biosynthesis,terpenoid backbone biosynthesis,fatty acid biosynthesis,ascorbate and aldarate metabolism,other types of O-glycan biosynthesis,and fatty acid metabolism.Glyoxylate and dicarboxylate metabolism,one carbon pool by folate,steroid biosynthesis,and cysteine and methionine metabolism were significantly enriched in the LS vs.Ctrl comparison.Additionally,the genes related to metabolism(acc,fas,hmgcr,hmgcs1,mvd,soat1,nsdhl,sqle,cel,fdft1,dnmt3a and mtr)were significantly up-regulated in the HS vs.Ctrl comparison.The genes related to metabolism(lipa,sqle,acc,fas,bhmt,mpst,dnmt3a,mtr,hao2,LOC111225351 and hmgcs1)were significantly up-regulated,while hmgcr and soat1 were significantly down-regulated in the LS vs.Ctrl compparison.These results suggest that salinity stress affects signaling pathways and genes’expressions involved in metabolic processes in the brain,and the differences in metabolism play an important role in adaptation to hyperhaline or hypohaline environments in spotted scat.This research provides a comprehensive overview of transcriptional changes in the brain under hyperhaline or hypohaline conditions,which is helpful to understand the mechanisms underlying salinity adaptation in euryhaline fishes. 展开更多
关键词 Scatophagus argus BRAIN SALINITY transcriptome analysis
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Prediction of the potential distribution and analysis of the freezing injury risk of winter wheat on the Loess Plateau under climate change
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作者 Qing Liang Xujing Yang +9 位作者 Yuheng Huang Zhenwei Yang Meichen Feng Mingxing Qing Chao Wang Wude Yang Zhigang Wang Meijun Zhang Lujie Xiao Xiaoyan Song 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第9期2941-2954,共14页
Determining the suitable areas for winter wheat under climate change and assessing the risk of freezing injury are crucial for the cultivation of winter wheat.We used an optimized Maximum Entropy(MaxEnt)Model to predi... Determining the suitable areas for winter wheat under climate change and assessing the risk of freezing injury are crucial for the cultivation of winter wheat.We used an optimized Maximum Entropy(MaxEnt)Model to predict the potential distribution of winter wheat in the current period(1970-2020)and the future period(2021-2100)under four shared socioeconomic pathway scenarios(SSPs).We applied statistical downscaling methods to downscale future climate data,established a scientific and practical freezing injury index(FII)by considering the growth period of winter wheat,and analyzed the characteristics of abrupt changes in winter wheat freezing injury by using the Mann-Kendall(M-K)test.The results showed that the prediction accuracy AUC value of the MaxEnt Model reached 0.976.The minimum temperature in the coldest month,precipitation in the wettest season and annual precipitation were the main factors affecting the spatial distribution of winter wheat.The total suitable area of winter wheat was approximately 4.40×10^(7)ha in the current period.In the 2070s,the moderately suitable areas had the greatest increase by 9.02×10^(5)ha under SSP245 and the least increase by 6.53×10^(5)ha under SSP370.The centroid coordinates of the total suitable areas tended to move northward.The potential risks of freezing injury in the high-latitude and-altitude areas of the Loess Plateau,China increased significantly.The northern areas of Xinzhou in Shanxi Province,China suffered the most serious freezing injury,and the southern areas of the Loess Plateau suffered the least.Environmental factors such as temperature,precipitation and geographical location had important impacts on the suitable area distribution and freezing injury risk of winter wheat.In the future,greater attention should be paid to the northward boundaries of both the winter wheat planting areas and the areas of freezing injury risk to provide the early warning of freezing injury and implement corresponding management strategies. 展开更多
关键词 climate change scenarios winter wheat freezing injury risk DOWNSCALING MAXENT
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Comparative Analysis of Reaction to Fire and Flammability of Hemp Shives Insulation Boards with Incorporated Microencapsulated Phase Change Materials
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作者 Inga Zotova Edgars Kirilovs Laura Ziemele 《Journal of Renewable Materials》 EI CAS 2024年第3期603-613,共11页
Nowadays buildings contain innovative materials,materials from local resources,production surpluses and rapidly renewable natural resources.Phase Change Materials(PCM)are one such group of novel materials which reduce... Nowadays buildings contain innovative materials,materials from local resources,production surpluses and rapidly renewable natural resources.Phase Change Materials(PCM)are one such group of novel materials which reduce building energy consumption.With the wider availability of microencapsulated PCM,there is an opportunity to develop a new type of insulating materials,combinate PCM with traditional insulation materials for latent heat energy storage.These materials are typically flammable and are located on the interior wall finishing yet there has been no detailed assessment of their fire performance.In this research work prototypes of low-density insulating boards for indoor spaces from hemp shives using carbamide resin binder and cold pressing were studied.Bench-scale cone calorimeter tests were conducted to evaluate fire risk,with a focus on assessing material flammability properties and the influence of PCM on the results.In this research,the amount of smoke,heat release rate,effective heat of combustion,specific extinction coefficient,mass loss,carbon dioxide yield,specific loss factor,ignition time of hemp straws samples and samples of hemp straws with 10%and without PCM admixture were compared.There is a risk of flammability for PCM and their fire reaction has not been evaluated when incorporating PCM into interior wall finishing boards.The obtained results can be used by designers to balance the potential energy savings of using PCM with a more complete understanding and predictability of the associated fire risk when using the proposed boards.It also allows for appropriate risk mitigation strategies. 展开更多
关键词 Encapsuled phase change material renewable resources reaction to fire FLAMMABILITY
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Analysis of Spatiotemporal Changes in Integrated Land Productivity in Chongqing from 1997 to 2023
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作者 Lei LUO Jinrong YANG 《Asian Agricultural Research》 2024年第8期1-5,49,共6页
[Objectives]Integrated land productivity can reflect the comprehensive utilization of land and the overall output level,which is the most basic and commonly used indicator in assessing land use efficiency.This thesis ... [Objectives]Integrated land productivity can reflect the comprehensive utilization of land and the overall output level,which is the most basic and commonly used indicator in assessing land use efficiency.This thesis aims to analyze the spatial and temporal changes of integrated land productivity in Chongqing from 1997 to 2023 in order to assess its land use efficiency.[Methods]This study measured the integrated land productivity of Chongqing Municipality,the only municipality directly under the central government in the western part of China,over the past 26 years(1997-2023)through relevant surveys and statistical data,and analyzed in depth the integrated land productivity of the 38 districts and counties under the jurisdiction of Chongqing,as well as the functional sub-districts of the"one district and two clusters"and the"one district and two clusters"in Chongqing.It also analyzes the characteristics of spatial and temporal differences in land productivity in 38 districts and counties under the jurisdiction of Chongqing and"one district and two clusters".[Results]The results of the study show that over the past 26 years,the integrated land productivity of Chongqing has shown an annual growth trend,and the integrated land productivity of the 38 districts and counties and the functional subregions of"one district and two clusters"has also increased significantly,but the average annual growth rate of the integrated land productivity varies among different regions.From the perspective of spatial differences,there are significant differences in land productivity among the 38 districts and counties of Chongqing and the functional subregions of"one district and two clusters",which are mainly due to the different natural conditions,economic development levels and functional positioning of each region.[Conclusions]Based on the results of the study and the actual situation of Chongqing,this paper puts forward the leading measures to improve the integrated land productivity,with a view to providing a reference basis for Chongqing to improve the efficiency of land use and promote the sustainable use of land resources. 展开更多
关键词 INTEGRATED LAND PRODUCTIVITY Spatial and TEMPORAL changes CHONGQING
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An Analysis of Liberia’s Vulnerability to Climate Change in the Context of Least Developed Countries (LDCs): A Review
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作者 Charles Flomo Togbah 《American Journal of Climate Change》 2024年第2期230-250,共21页
Climate change is an alarming global challenge, particularly affecting the least developed countries (LDCs) including Liberia. These countries, located in regions prone to unpredictable temperature and precipitation c... Climate change is an alarming global challenge, particularly affecting the least developed countries (LDCs) including Liberia. These countries, located in regions prone to unpredictable temperature and precipitation changes, are facing significant challenges, particularly in climate-sensitive sectors such as mining and agriculture. LDCs need more resilience to adverse climate shocks but have limited capacity for adaptation compared to other developed and developing nations. This paper examines Liberia’s susceptibility to climate change as a least developed country, focusing on its exposure, sensitivity, and adaptive capacity. It provides an overview of LDCs and outlines the global distribution of carbon dioxide emissions. The paper also evaluates specific challenges that amplify Liberia’s vulnerability and constrain sustainable adaptation, providing insight into climate change’s existing and potential effects. The paper emphasizes the urgency of addressing climate impacts on Liberia and calls for concerted local and international efforts for effective and sustainable mitigation efforts. It provides recommendations for policy decisions and calls for further research on climate change mitigation and adaptation. 展开更多
关键词 Least Developed Countries LIBERIA Climate change VULNERABILITY POVERTY HUNGER Disease Research and Development (R&D) Adaptation
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Spatial Analysis of Structural Changes and Floristic Distribution of Forest Landscapes in the Centre-West Region of Burkina Faso
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作者 Stéphane Koudougou Oumar Kaboré 《Journal of Geoscience and Environment Protection》 2024年第9期246-268,共23页
Land use and occupation dynamics impact landscape structure, diversity, richness and balance of vegetation cover. The aim of this study is to describe the process of fragmentation of the forest landscape from 1990 to ... Land use and occupation dynamics impact landscape structure, diversity, richness and balance of vegetation cover. The aim of this study is to describe the process of fragmentation of the forest landscape from 1990 to 2020 and its effects on the degradation of the floristic characteristics of the vegetation in the Central West region of Burkina Faso. To achieve this, satellite data were collected and processed as part of a mapping approach to describing the landscape and the different types of landscape fragmentation. Mapping indices of landscape fragmentation (relative richness, change process, patch zones, Shannon diversity index) were also calculated. These indices were programmed in Idrisi Selva’s Landscape Pattern and change process analysis module. Spatio-temporal analysis revealed that in 1990, the landscape was dominated by natural vegetation formations, covering 66.33% of the territory. By 2020, these had been degraded to 44.80% by farmlands. The mapping analysis of indices also showed that the study area is characterized by four types of landscape fragmentation, including attrition, aggregation, creation and dissection. We also observed an abundant homogeneity, diversity and richness of conservation areas with legal and land tenure status. However, the structure is heterogeneous in landscapes outside protected areas and in areas under human occupation. This shows the crucial role played by conservation areas in preserving and balancing the diversity of vegetative cover in the study area. 展开更多
关键词 change Process FRAGMENTATION Remote Sensing LANDSCAPE Burkina Faso
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Physical Analysis of Atmospheric Phenomena Associated with Climatic Storms: Approach Study Related to Climate Change on Earth
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作者 Wend Dolean Arsène Ilboudo 《Atmospheric and Climate Sciences》 2024年第4期355-367,共13页
Atmospheric phenomena are physical phenomena resulting from the correlation of atmospheric parameters of natural origin. They are associated with climatic storms and include lightning, thunder, global warming, wind, e... Atmospheric phenomena are physical phenomena resulting from the correlation of atmospheric parameters of natural origin. They are associated with climatic storms and include lightning, thunder, global warming, wind, evaporation, rain, clouds, and snow. The formation and evolution of these phenomena remain complex according to their natural reference parameters. The numerical models defined in this study are equations based on models of atmospheric parameters. Applied in the atmosphere, they yield the equation of the key atmospheric phenomena. The distribution of these phenomena across the entire planet is the origin of the formation of climatic regions. Indeed, the constants obtained are 275.16 km/s for the speed of lightning, 3.99 GJ for the discharge energy of a thunderbolt, 276.15˚K for the temperature of global warming, 3.993 Km/h for the formation speed of winds and cyclones, 2.9963 Km/h for the speed of evaporation, 278.16˚K for the formation of rain, 274.1596˚K for the formation of clouds, and 274.1632˚K for snow formation. Moreover, this research conducts an analytical study approach to the phenomenon of climate change in the current era of industrialization, specifically analyzing the direct effects of global warming on atmospheric phenomena. Thus, with a temperature of 53.45˚C, global warming is considered maximal and will lead to very abundant rain and snow precipitations with maximum PW at 12.5 and 11.1 g/cm2 of water, surface water evaporation fluxes significantly above normal at a speed of 6.55 Km/h, increasingly violent winds at speeds far exceeding 5.43 Km/h, and catastrophic climatic effects. In summary, the aim of this research is to define the main natural phenomena associated with global climatic storms and to study the real impact of climate change on Earth. 展开更多
关键词 Atmospheric Phenomenon Climate change Climatic Catastrophe
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An Analysis of Land Use and Land Cover Changes, and Implications for Conservation in Mukumbura (Ward 2), Mt Darwin, Zimbabwe, 2002-2022
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作者 Musekiwa Innocent Maruza Edson Gandiwa +3 位作者 Never Muboko Ishmael Sango Tawanda Tarakini Nobert Tafadzwa Mukomberanwa 《Open Journal of Ecology》 2024年第9期706-730,共25页
Understanding trends of land use land cover (LULC) changes is important for biodiversity monitoring and conservation planning, and identifying the areas affected by change and designing sustainable solutions to reduce... Understanding trends of land use land cover (LULC) changes is important for biodiversity monitoring and conservation planning, and identifying the areas affected by change and designing sustainable solutions to reduce the changes. The study aims to evaluate and quantify the historical changes in land use and land cover in Mukumbura (Ward 2), Mt Darwin, Zimbabwe, from 2002 to 2022. The objective of the study was to analyse the LULC changes in Ward 2 (Mukumbura), Mt Darwin, Northern Zimbabwe, for a period of 20 years using geospatial techniques. Landsat satellite images were processed using Google Earth Engine (GEE) and the supervised classification with maximum likelihood algorithm was employed to generate LULC maps between 2002 and 2022 with a five (5) year interval, investigating the following variables, forest cover, barren land, water cover and the fields. Findings revealed a substantial reduction in forest cover by 38.8%, water bodies (wetlands, ponds, and rivers) declined by 55.6%, whilst fields (crop/agricultural fields) increased by 93.3% and the barren land cover increased by 26.3% from 2002 to 2022. These findings point to substantial changes in LULC over the observed years. LULC changes have resulted in habitat fragmentation, reduced biodiversity, and the disruption of ecosystem functions. The study concludes that if these deforestation trends, cultivation, and settlement land expansion continue, the ward will have limited indigenous fruit trees. Therefore, the causes for LULC changes must be controlled, sustainable forest resources use practiced, hence the need to domesticate the indigenous fruit trees in arborloo toilets. 展开更多
关键词 Anthropogenic Activities DEFORESTATION Geospatial analysis Land Use/Land Cover Supervised Classification
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Analysis of piezoelectric semiconductor fibers under gradient temperature changes
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作者 Shuangpeng LI Ruoran CHENG +1 位作者 Nannan MA Chunli ZHANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第2期311-320,共10页
Piezoelectric semiconductors(PSs)possess both semiconducting properties and piezoelectric coupling effects,making them optimal building blocks for semiconductor devices.PS fiber-like structures have wide applications ... Piezoelectric semiconductors(PSs)possess both semiconducting properties and piezoelectric coupling effects,making them optimal building blocks for semiconductor devices.PS fiber-like structures have wide applications in multi-functional semiconductor devices.In this paper,a one-dimensional(1D)theoretical model is established to describe the piezotronic responses of a PS fiber under gradient temperature changes.The theoretical model aims to explain the mechanism behind the resistance change caused by such gradient temperature changes.Numerical results demonstrate that a gradient temperature change significantly affects the physical fields within the PS fiber,and can induce changes in its surface resistance.It provides important theoretical guidance on the development of piezotronic devices that are sensitive to temperature effects. 展开更多
关键词 piezoelectric semiconductor(PS)fiber one-dimensional(1D)model piezotronic effect gradient temperature change
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Analysis of Imaging Characteristics and Dynamic Changes of 3 Cases of Severe Novel Coronavirus Pneumonia in Qinghai Province
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作者 Yingfang Yu Ruiyun Zhao +3 位作者 Changde Li Fuqiang Ma Lingyun Guo Yang Li 《Journal of Clinical and Nursing Research》 2024年第3期120-126,共7页
Objective:To analyze the characteristics,dynamic changes,and outcomes of the first imaging manifestations of 3 patients with severe COVID-19 in our hospital.Methods:Computed tomography(CT)findings of 3 patients with s... Objective:To analyze the characteristics,dynamic changes,and outcomes of the first imaging manifestations of 3 patients with severe COVID-19 in our hospital.Methods:Computed tomography(CT)findings of 3 patients with severe COVID-19 who tested positive by the nucleic acid test in our hospital were selected,mainly focusing on the morphology,distribution characteristics,and dynamic changes of the first CT findings.Results:3 patients with severe pneumonia were older,with one aged 80.The first chest CT examination for all 3 patients differed.Imaging showed a leafy distribution of consolidation,primarily affecting the lower lobes of both lungs and extending subpleurally.A grid-like pattern was observed,along with changes in the consolidation and air bronchogram.These changes had slower absorption,especially in patients with underlying diseases.Conclusion:CT manifestations of severe COVID-19 have specific characteristics and the analysis of their characteristics and dynamic changes provide valuable insights for clinical treatment. 展开更多
关键词 COVID-19 IMAGING CT findings Dynamic changes
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Analysis of the Dynamics of Policy Changes in the International Border Cooperation Center under the Perspective of Multi-Source Flow Theory
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作者 Xinna Shi Tayierjiang Yasheng +2 位作者 Siyuan Li Ming Cai Shichuan Yan 《Proceedings of Business and Economic Studies》 2024年第4期153-159,共7页
The China-Kazakhstan Horgos Frontier International Cooperation Center has been established for nearly 20 years,and its targeted policies have gone through the stages of initiative,negotiation and modification,official... The China-Kazakhstan Horgos Frontier International Cooperation Center has been established for nearly 20 years,and its targeted policies have gone through the stages of initiative,negotiation and modification,official operation,and optimization and enhancement.This paper explores the problems,policy,and political sources of policy changes since the establishment of the Horgos International Border Cooperation Center by applying the multi-source flow theory to find the opening of the problematic and political windows.It also constructs a model of policy change dynamics to provide suggestions on how the government should better promote the good development of China’s first transnational cooperation center. 展开更多
关键词 Horgos Cooperative centers Policy changes Multiple source flows
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Correlation Analysis Between Changes of D-Dimer Level and Rheumatoid Arthritis Complicated with Interstitial Lung Disease
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作者 Ying Li 《Journal of Clinical and Nursing Research》 2024年第6期393-397,共5页
Objective:To explore the correlation between the change of D-dimer level and rheumatoid arthritis complicated with interstitial lung disease.Methods:From January 2022 to February 2024,20 rheumatoid arthritis patients ... Objective:To explore the correlation between the change of D-dimer level and rheumatoid arthritis complicated with interstitial lung disease.Methods:From January 2022 to February 2024,20 rheumatoid arthritis patients complicated with interstitial lung disease(interstitial lung disease group),20 rheumatoid arthritis patients without interstitial lung disease(without interstitial lung disease group),and 20 healthy people(control group)in Xijing Hospital were selected for this study.The fasting venous blood of the three groups of subjects was collected and their D-dimer,C-reactive protein(CRP),rheumatoid factor(RF),and erythrocyte sedimentation rate(ESR)were detected.Subsequently,the correlation between each index and rheumatoid arthritis complicated with interstitial lung disease was analyzed.Results:The D-dimer level of the interstitial lung disease group was significantly higher than the other two groups(P<0.05).The D-dimer level of the group without interstitial lung disease was significantly higher than the control group(P<0.05).CRP levels in the interstitial lung disease group and the group without interstitial lung disease were significantly higher than those of the control group(P<0.05).The ESR and RF levels of the interstitial lung disease group were significantly higher than the other two groups(P<0.05).The levels of ESR and RF levels of the group without interstitial lung disease were significantly higher than the control group(P<0.05).Conclusion:D-dimer levels of rheumatoid arthritis patients are higher than those of healthy individuals,and those complicated with interstitial lung disease present even higher levels.This finding shows that there is a correlation between D-dimer levels and rheumatoid arthritis with interstitial lung disease,which may facilitate the evaluation and diagnosis of this disease. 展开更多
关键词 D-DIMER Rheumatoid arthritis complicated with interstitial lung disease ESR Rheumatoid factor Correlation analysis
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Screening biomarkers for spinal cord injury using weighted gene co-expression network analysis and machine learning 被引量:5
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作者 Xiaolu Li Ye Yang +3 位作者 Senming Xu Yuchang Gui Jianmin Chen Jianwen Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第12期2723-2734,共12页
Immune changes and inflammatory responses have been identified as central events in the pathological process of spinal co rd injury.They can greatly affect nerve regeneration and functional recovery.However,there is s... Immune changes and inflammatory responses have been identified as central events in the pathological process of spinal co rd injury.They can greatly affect nerve regeneration and functional recovery.However,there is still limited understanding of the peripheral immune inflammato ry response in spinal cord inju ry.In this study.we obtained microRNA expression profiles from the peripheral blood of patients with spinal co rd injury using high-throughput sequencing.We also obtained the mRNA expression profile of spinal cord injury patients from the Gene Expression Omnibus(GEO)database(GSE151371).We identified 54 differentially expressed microRNAs and 1656 diffe rentially expressed genes using bioinformatics approaches.Functional enrichment analysis revealed that various common immune and inflammation-related signaling pathways,such as neutrophil extracellular trap formation pathway,T cell receptor signaling pathway,and nuclear factor-κB signal pathway,we re abnormally activated or inhibited in spinal cord inju ry patient samples.We applied an integrated strategy that combines weighted gene co-expression network analysis,LASSO logistic regression,and SVM-RFE algorithm and identified three biomarke rs associated with spinal cord injury:ANO10,BST1,and ZFP36L2.We verified the expression levels and diagnostic perfo rmance of these three genes in the original training dataset and clinical samples through the receiver operating characteristic curve.Quantitative polymerase chain reaction results showed that ANO20 and BST1 mRNA levels were increased and ZFP36L2 mRNA was decreased in the peripheral blood of spinal cord injury patients.We also constructed a small RNA-mRNA interaction network using Cytoscape.Additionally,we evaluated the proportion of 22 types of immune cells in the peripheral blood of spinal co rd injury patients using the CIBERSORT tool.The proportions of naive B cells,plasma cells,monocytes,and neutrophils were increased while the proportions of memory B cells,CD8^(+)T cells,resting natural killer cells,resting dendritic cells,and eosinophils were markedly decreased in spinal cord injury patients increased compared with healthy subjects,and ANO10,BST1 and ZFP26L2we re closely related to the proportion of certain immune cell types.The findings from this study provide new directions for the development of treatment strategies related to immune inflammation in spinal co rd inju ry and suggest that ANO10,BST2,and ZFP36L2 are potential biomarkers for spinal cord injury.The study was registe red in the Chinese Clinical Trial Registry(registration No.ChiCTR2200066985,December 12,2022). 展开更多
关键词 bioinformatics analysis BIOMARKER CIBERSORT GEO dataset LASSO miRNA-mRNA network RNA sequencing spinal cord injury SVM-RFE weighted gene co-expression network analysis
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Analysis of influence of heat exchangerfouling on heat transfer performancebased on thermal fluid coupling 被引量:1
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作者 HUANG Si MURAD Tariq +2 位作者 NIU Qifeng LIN Guangtang CHEN Jianxun 《排灌机械工程学报》 CSCD 北大核心 2023年第7期695-700,共6页
A study on heat transfer performance by thermal fluid coupling simulation for the fouling in a shell-tube heat exchanger used in engineering was presented. The coupling simulation was performed in a fluid and solid do... A study on heat transfer performance by thermal fluid coupling simulation for the fouling in a shell-tube heat exchanger used in engineering was presented. The coupling simulation was performed in a fluid and solid domains under three different fouling conditions: fouling inside the tube, fouling outside the tube, and fouling inside the shell. The flow field, temperature, and pressure distributions in the heat exchanger were solved numerically to analyze the heat transfer performance parameters, such as thermal resistance. It is found that the pressure drop of the heat exchanger and the thermal resistance of the tube wall increase by nearly 30% and 20%, respectively, when the relative fouling thickness reaches 10%. The fouling inside the tube has more impact on the heat transfer performance of the heat exchanger, and the fouling inside the shell has less impact. 展开更多
关键词 shell-tube heat exchanger thermal fluid coupling fouling thermal resistance heat transfer analysis
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Social-ecological perspective on the suicidal behaviour factors of early adolescents in China:a network analysis 被引量:3
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作者 Yuan Li Peiying Li +5 位作者 Mengyuan Yuan Yonghan Li Xueying Zhang Juan Chen Gengfu Wang Puyu Su 《General Psychiatry》 CSCD 2024年第1期143-150,共8页
Background In early adolescence,youth are highly prone to suicidal behaviours.Identifying modifiable risk factors during this critical phase is a priority to inform effective suicide prevention strategies.Aims To expl... Background In early adolescence,youth are highly prone to suicidal behaviours.Identifying modifiable risk factors during this critical phase is a priority to inform effective suicide prevention strategies.Aims To explore the risk and protective factors of suicidal behaviours(ie,suicidal ideation,plans and attempts)in early adolescence in China using a social-ecological perspective.Methods Using data from the cross-sectional project‘Healthy and Risky Behaviours Among Middle School Students in Anhui Province,China',stratified random cluster sampling was used to select 5724 middle school students who had completed self-report questionnaires in November 2020.Network analysis was employed to examine the correlates of suicidal ideation,plans and attempts at four levels,namely individual(sex,academic performance,serious physical llness/disability,history of self-harm,depression,impulsivity,sleep problems,resilience),family(family economic status,relationship with mother,relationship with father,family violence,childhood abuse,parental mental illness),school(relationship with teachers,relationship with classmates,school-bullying victimisation and perpetration)and social(social support,satisfaction with society).Results In total,37.9%,19.0%and 5.5%of the students reported suicidal ideation,plans and attempts in the past 6 months,respectively.The estimated network revealed that suicidal ideation,plans and attempts were collectively associated with a history of self-harm,sleep problems,childhood abuse,school bullying and victimisation.Centrality analysis indicated that the most influential nodes in the network were history of self-harm and childhood abuse.Notably,the network also showed unique correlates of suicidal ideation(sex,weight=0.60;impulsivity,weight=0.24;family violence,weight=0.17;relationship with teachers,weight=-0.03;school-bullying perpetration,weight=0.22),suicidal plans(social support,weight=-0.15)and suicidal attempts(relationship with mother,weight=-0.10;parental mental llness,weight=0.61).Conclusions This study identified the correlates of suicidal ideation,plans and attempts,and provided practical implications for suicide prevention for young adolescents in China.Firstly,this study highlighted the importance of joint interventions across multiple departments.Secondly,the common risk factors of suicidal ideation,plans and attempts were elucidated.Thirdly,this study proposed target interventions to address the unique influencing factors of suicidal ideation,plans and attempts. 展开更多
关键词 NETWORK analysis PREVENTION
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Knowledge flow analysis of knowledge co-production-based climate change adaptation for lowland rice farmers in Bulukumba Regency,Indonesia
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作者 Arifah Darmawan SALMAN +1 位作者 Amir YASSI Eymal Bahsar DEMMALLINO 《Regional Sustainability》 2023年第2期194-202,共9页
To increase the resilience of farmers’livelihood systems,detailed knowledge of adaptation strategies for dealing with the impacts of climate change is required.Knowledge co-production approach is an adaptation strate... To increase the resilience of farmers’livelihood systems,detailed knowledge of adaptation strategies for dealing with the impacts of climate change is required.Knowledge co-production approach is an adaptation strategy that is considered appropriate in the context of the increasing frequency of disasters caused by climate change.Previous research of knowledge co-production on climate change adaptation in Indonesia is insufficient,particularly at local level,so we examined the flow of climate change adaptation knowledge in the knowledge co-production process through climate field school(CFS)activities in this study.We interviewed 120 people living in Bulukumba Regency,South Sulawesi Province,Indonesia,involving 12 crowds including male and female farmers participated in CFS and not participated in CFS,local government officials,agriculture extension workers,agricultural traders,farmers’family members and neighbors,etc.In brief,the 12 groups of people mainly include two categories of people,i.e.,people involved in CFS activities and outside CFS.We applied descriptive method and Social network analysis(SNA)to determine how knowledge flow in the community network and which groups of actors are important for knowledge flow.The findings of this study reveal that participants in CFS activities convey the knowledge they acquired formally(i.e.,from TV,radio,government,etc.)and informally(i.e.,from market,friends,relatives,etc.)to other actors,especially to their families and neighbors.The results also show that the acquisition and sharing of knowledge facilitate the flow of climate change adaptation knowledge based on knowledge co-operation.In addition,the findings highlight the key role of actors in the knowledge transfer process,and key actors involved in disseminating information about climate change adaptation.To be specific,among all the actors,family member and neighbor of CFS actor are the most common actors in disseminating climate knowledge information and closest to other actors in the network;agricultural trader and family member of CFS actor collaborate most with other actors in the community network;and farmers participated in CFS,including those heads of farmer groups,agricultural extension workers,and local government officials are more willing to contact with other actors in the network.To facilitate the flow of knowledge on climate change adaptation,CFS activities should be conducted regularly and CFS models that fit the situation of farmers’vulnerability to climate change should be developed. 展开更多
关键词 Climate change adaptation Knowledge flow Knowledge co-production Climate field school(CFS) Social network analysis(SNA) Indonesia
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Analysis of Land Use Change and Driving Factors in Mojiang County Based on PLUS Model
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作者 Chunfeng YANG Haiying PENG 《Asian Agricultural Research》 2023年第7期22-27,共6页
[Objectives]To explore the characteristics of land use change and its main influencing factors in Mojiang County from 2000 to 2020,and try to provide a scientific reference for alleviating the contradiction between ma... [Objectives]To explore the characteristics of land use change and its main influencing factors in Mojiang County from 2000 to 2020,and try to provide a scientific reference for alleviating the contradiction between man and land in Mojiang County and realizing the sustainable development of regional land resources.[Methods]Based on the land cover data and socio-economic data of Mojiang County from 2000 to 2020,the dynamic degree of land use,land use transfer matrix and center-of-gravity transfer model were calculated,and the temporal and spatial change characteristics and driving factors of various types of land use were calculated by PLUS model.[Results]From 2000 to 2020,the area and proportion of grassland,waters and construction land in Mojiang County showed an upward trend,while the area and proportion of cultivated land and forest land showed a downward trend.Among them,cultivated land was mainly converted into forest land and grassland,and some were converted into waters and construction land;forest land was mainly converted into cultivated land and grassland,and part of it was converted into waters and construction land.From 2000 to 2020,the center-of-gravity of cultivated land,forest land and construction land in Mojiang County moved to the southeast of the county,and the moving rates were 0.66,1.97 and 10.58 km/yr,respectively;the center-of-gravity of grassland and waters moved to the southwest of the county,and the moving rates were 1.30 and 20.20 km/yr,respectively.Distance from road,distance from government and distance from waters are the main driving forces affecting land use change in Mojiang County;the forecast shows that in 2040,the area of grassland and forest land in Mojiang County will continue to decrease,the area of cultivated land will turn to rise,and the area of waters and construction land will continue to rise.[Conclusions]Reasonable planning and optimizing the allocation of cultivated land and forest land structure and strict control of the expansion scale of construction land are necessary measures to ensure the coordinated development of regional land rational use and economic construction. 展开更多
关键词 Land use change Comparative analysis Center of gravity PREDICTION PLUS model
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