The digital economy has become an important driver for stimulating economic growth.The digital economy has now widely penetrated the fields of economy and society,providing new opportunities for the develop‐ment of u...The digital economy has become an important driver for stimulating economic growth.The digital economy has now widely penetrated the fields of economy and society,providing new opportunities for the develop‐ment of urban-rural integration.Based on panel data for 30 provinces in China from 2011 to 2020,this study constructed an index system for the integration of the digital economy and the development of urban-rural areas and conducted a systematic measurement analysis.Additionally,we used a two-step system of GMM estimation to analyze the impact of the digital economy on the development of urban-rural integra‐tion.The findings demonstrate the significant imbalance paradox of China’s digital economy development,which is shown in a gradient where the eastern region is higher than the center and the central region is higher than the west.Urban-rural integration levels in China fluctuate and display geographical variance,typically displaying high levels in the east and low levels in the west.Urban-rural integration is significantly encouraged by the digital economy,yet it varies in variability between different areas and dimensions.Addi‐tionally,rural human capital moderates the favorable effects of the digital economy on urban-rural integra‐tion.As a result,in order to achieve the integrated development of urban and rural areas,it is imperative to fully exploit the active role of the digital economy,better support the development of rural revitalization,bridge the“digital divide”between urban and rural development,and build a strong foundation for the for‐mation of a digital urban-rural integrated development pattern with urban and rural areas and common con‐struction and sharing.展开更多
The wingless-related integration site(WNT)proteins are a family of secreted glycoproteins that are evolutionarily conserved and are believed to be involved in evolution in vertebrates and invertebrates.WNT signaling p...The wingless-related integration site(WNT)proteins are a family of secreted glycoproteins that are evolutionarily conserved and are believed to be involved in evolution in vertebrates and invertebrates.WNT signaling pathways may be associated with limb regeneration and development in crustaceans.However,the detail mechanisms remain unclear.Therefore,the distribution of WNT4 in the hepatopancreas,muscle,hemocyte,ganglion,heart,eyestalk,gill tissue,and diff erent larvae development stages of the swimming crab(Portunus trituberculatus)were characterized using immunofl uorescence,real-time PCR,and Western blotting.Signifi cant PtWNT4 expression was detected in heart and eyestalk.In addition,PtWNT4 was expressed in all larval stages of P.trituberculatus with a dynamic expression pattern,especially in the eyestalk and other organs in the carapace area.The injection of WNT4 dsRNA into regenerative limbs signifi cantly decreased PtWNT4 mRNA levels in the eyestalk,heart,and muscle,resulting in 1.9-fold,2.2-fold,and 2.7-fold decreases compared with those detected in the group injected with crab saline(P<0.05),respectively,indicating successful gene silencing.Overall,expression analysis on the WNT4 using RNAi provides an insight to its functional mechanism during limb regeneration in P.trituberculatus.The results not only demonstrated the requirement for WNT4 in limb regeneration of Crustaceans,but also suggested its ability to promote larval development at specifi c stages.展开更多
Irrigation methods and nitrogen(N) fertilization modes have complicated impacts on wheat physiology, growth, and development, leading to the regulation of wheat grain yield and quality. However, the optimal water-N co...Irrigation methods and nitrogen(N) fertilization modes have complicated impacts on wheat physiology, growth, and development, leading to the regulation of wheat grain yield and quality. However, the optimal water-N combination for drip-irrigated winter wheat remains unclear. A two-year field study was conducted to evaluate the influences of various N-fertigation and water regimes on wheat post-anthesis grain weight variation, yield, grain NPK content, and grain quality. The two irrigation quotas were I_(45)(irrigation when crop evapotranspiration reduced by effective rainfall(ETa-P) reaches 45 mm) and I_(30)(irrigation when ETa-P reaches 30 mm), while the six N application rates were N_(0–100)(100% at jointing/booting), N_(25–75)(25% at sowing and 75% at jointing/booting), N_(50–50)(50% at sowing and 50% at jointing/booting), N_(75–25)(75% at sowing and 25% at jointing/booting), N_(100–0)(100% at sowing), and SRF100(100% of slow-release fertilizer at sowing). The experimental findings showed that post-anthesis grain weight variation, grain yield, grain NPK content, and grain quality were all markedly influenced by the various irrigation schedules and N-fertilization modes. The N_(50–50)treatment was more beneficial for winter wheat post-anthesis grain weight variation than the N_(100–0)and N_(0–100)treatments under the two irrigation quotas and during the two seasons. The highest grain yields of 9.72 and9.94(t ha^(-1)) were obtained with the I_(45)N_(50–50)treatment in 2020–2021 and 2021–2022, respectively. The grain crudeprotein was higher in the I_(45)SRF100treatment during the two seasons. The I_(45)N_(100–0)combination significantly(P<0.05)enhanced the content of grain total starch by 7.30 and 8.23% compared with the I_(45)N_(0–100)and I_(30)N_(0–100)treatments,respectively, during the 2021–2021 season. The I_(45)N_(100–0)treatment significantly(P<0.05) enhanced the content ofgrain total starch concentration by 7.77, 7.62 and 7.88% compared with the I_(45)N_(0–100), I_(30)N_(0–100), and I_(30)N_(25–75)treatments,respectively, in the 2021–2022 season. The principal component analysis(PCA) indicated that the N_(50–50)splitN-fertigation mode could be the optimal choice for farmers during winter wheat production via drip irrigation.展开更多
Intraspecific conflict induced by the innate aggressiveness is one of the main reasons for the extremely low survival rate in mud crab Scylla paramamosain aquaculture,which have impeded the sustainable culture of the ...Intraspecific conflict induced by the innate aggressiveness is one of the main reasons for the extremely low survival rate in mud crab Scylla paramamosain aquaculture,which have impeded the sustainable culture of the species.In this study,we first classified and quantified the aggressive behavior,and established a crab aggressive behavior model,laying the foundation for subsequent research on evaluating combat intensity.The contents of 5-hydroxytryptamine(5-HT),dopamine(DA),and cAMP in the hemolymph of the mud crabs before and after fighting were measured by high-performance liquid chromatography-mass spectrometry(HPLC-MS),and the mud crabs exhibited a significant increase of 5-HT(P<0.05),while the DA and cAMP decreased significantly(P<0.05).In addition,we applied EthoVision to examine the changes of the crab behavior after DA administration.After 0.5 h of injection,the movement speed,distance,duration of aggressive behavior,and intensity of aggression in the high concentration DA group were significantly higher than those in the saline injection group and the untreated control group(P<0.05).The results of real-time quantitative polymerase chain reaction(qRT PCR)analysis showed that the expression of DA 1 in the thoracic ganglia of the mud crabs was significantly down-regulated in the DA injection group,and the aggressive behavior was weakened.Conversely,DA1 expression was up-regulated when aggressive behavior was strengthened.Besides,there were significant differences in the expression levels of receptor expression genes including 5-HT1,5-HT2,and crustacean hyperglycemic hormone(CHH)in different tissues,indicating that the alteration of aggressive behavior of the mud crab after injection with different concentrations of DA could be regulated by changes in the expression levels of corresponding receptor genes.Our results contribute to a deeper analysis of the aggressive behavior mechanism of the mud crabs and provide a theoretical basis for reducing fighting-related mortalities in aquaculture.展开更多
The composites prepared by combining lightweight carbon materials with magnetic metals have demonstrated excellent dielectric and magnetic properties,indicating potential applications in the field of electromagnetic w...The composites prepared by combining lightweight carbon materials with magnetic metals have demonstrated excellent dielectric and magnetic properties,indicating potential applications in the field of electromagnetic wave(EMW)absorption.However,the rational microstructure design and component optimization of these composites in regulating their magnetic-dielectric balance to achieve high-performance EMW absorption remains challenging.Herein,hierarchical yolk-shell Fe@SiO_(2)@NC composites with dual impedance matching layers and dual built-in electric fields were prepared by self-template aggregation and in situ reduction strategies.The introduction of a SiO_(2)wave-transparent layer into a conventional dielectric-magnetic system has resulted in the successful realization of nanoscale precise impedance matching regulation in absorbers,thereby enabling effective ultra-wideband EMW absorption.The dual impedance matching layers of the internal void layer and the SiO_(2)wave-transparent layer facilitate multiple scattering and reflection of EMWs within the absorbers,and the dual built-in electric fields of Fe/SiO_(2)and SiO_(2)/NC can effectively enhance interfacial polarization effect to attenuate EMWs.The predominantly optimized Fe@SiO_(2)@NC-2 exhibits an ultra-wide effective absorption bandwidth(EAB)of 7.10 GHz and an impressive minimum reflection loss(RL_(min))of−64.83 dB,indicating that optimizing the impedance matching via quantitative design can maximize the EMW absorption performance.This work provides a straightforward yet effective approach for constructing multi-component materials with hierarchical yolk-shell structure,which offers valuable insight into the microstructure design and component optimization of innovative EMW absorption materials.展开更多
Today,resource depletion threatens a number of resource-based cities in China.The ecological security problem caused by the long-term exploitation of natural resources is a key issue to be solved in the development of...Today,resource depletion threatens a number of resource-based cities in China.The ecological security problem caused by the long-term exploitation of natural resources is a key issue to be solved in the development of resource-exhausted cities.Using 23 indicators,this study evaluated the ecological security status and development trends of 21 resource-exhausted cities in China from 2011 to 2017.The results showed that from 2011 to 2015,the overall ecological security of this type of city was low,with over 60%of the cities at an unsafe level.However,ecological security improved rapidly after 2016,and by 2017,all of the cities had reached the critical safety level.The top 10 indicators of ecological security included industrial sulfur dioxide emissions,water supply,agricultural fertilizer application,and forest coverage.These 10 indicators’cumulative contribution to ecological security was 48.3%;among them,reducing industrial sulfur dioxide emissions contributed the most at 5.7%.These findings can help governments better understand the ecological security status of resource-exhausted cities,and it can provide a reference for the allocation of funds and other resources to improve the ecological safety of these cities.展开更多
High-temperature electromagnetic(EM) protection materials integrated of multiple EM protection mechanisms and functions are regarded as desirable candidates for solving EM interference over a wide temperature range.In...High-temperature electromagnetic(EM) protection materials integrated of multiple EM protection mechanisms and functions are regarded as desirable candidates for solving EM interference over a wide temperature range.In this work,a novel microwave modulator is fabricated by introducing carbonyl iron particles(CIP)/resin into channels of carbonized wood(C-wood).Innovatively,the spaced arrangement of two microwave absorbents not only achieves a synergistic enhancement of magnetic and dielectric losses,but also breaks the translational invariance of EM characteristics in the horizontal direction to obtain multiple phase discontinuities in the frequency range of 8.2-18.0 GHz achieving modulation of reflected wave radiation direction.Accordingly,CIP/C-wood microwave modulator demonstrates the maximum effective bandwidth of 5.2 GHz and the maximum EM protection efficiency over 97% with a thickness of only 1.5 mm in the temperature range 298-673 K.Besides,CIP/C-wood microwave modulator shows stable and low thermal conductivities,as well as monotonic electrical conductivity-temperature characteristics,therefore it can also achieve thermal infrared stealth and working temperature monitoring in wide temperature ranges.This work provides an inspiration for the design of high-temperature EM protection materials with multiple EM protection mechanisms and functions.展开更多
Background and Objective(TGA)is a rare life-threatening form of congenital heart disease(CHD)with little known etiology.The recurrence rate in siblings and offspring of TGA patients has been observed higher than gener...Background and Objective(TGA)is a rare life-threatening form of congenital heart disease(CHD)with little known etiology.The recurrence rate in siblings and offspring of TGA patients has been observed higher than general population,implying the contribution of genetic factors.Indeed,family studies identified copy number variants e.g.22q11.2 deletions and point mutations e.g.NKX2-5 underlying genetic susceptibility to TGA or other forms of CHD.However,these genetic variants revealed in family studies are seldom observed in sporadic TGA subjects,indicating a distinct genetic etiology in sporadic TGA that remains to be explored.We sought to explore the genetic etiology of sporadic TGA at different levels including mutations,genes and pathways.展开更多
The interplay between solid electrolytes and electrodes is of vital importance to the performance of allsolid-state Li batteries.Recently,halide superionic conductors have emerged as a new family of high-performance s...The interplay between solid electrolytes and electrodes is of vital importance to the performance of allsolid-state Li batteries.Recently,halide superionic conductors have emerged as a new family of high-performance solid electrolytes,but their compatibility with Li metal,i.e.,the anode with the highest theoretical capacity,has not been systematically studied.Here,we investigate the interaction between Li metal and two representative halide solid electrolytes:Li_(3)YCl_(6)and Li_(3)YBr_(6).Both materials are found to form interphases with Li,similar to most solid electrolytes.However,the interphases observed here contain electronic conducting components,which are detrimental to their compatibility with Li.By elucidating this phenomenon,the present study provides guiding principles for improving the Li compatibility of halide solid electrolytes.展开更多
Climate change has limited crop productivity worldwide.Understanding crop response to global climate changes is vital to maintaining agricultural sustainable development.A two-year experiment was conducted to investig...Climate change has limited crop productivity worldwide.Understanding crop response to global climate changes is vital to maintaining agricultural sustainable development.A two-year experiment was conducted to investigate the effects of warming and drought on crop growth and winter wheat yield production.The results showed that both warming and drought shortened the crop growth period,reduced the leaf area index,and increased winter wheat biomass accumulation.Under sufficient water supply conditions,warming would increase photosynthetic and transpiration rates and water use efficiency,while under water deficit conditions,the opposite was observed.Under warming conditions,the grain yield of the water deficit treatment was 8.9%lower than that of the sufficient water supply treatment.Under non-warming conditions,the grain yield of water deficit treatment was 12.4%lower than that of the sufficient water supply.Under the conditions of water-sufficient supply,the grain yield of the warming treatment was 4.4%lower than that of the non-warming treatment,and under the conditions of water deficit,the grain yield of the warming treatment was 1.3%lower than that of the non-warming treatment.Warming tends to decrease wheat growth and grain yield,but sufficient water supply could improve winter wheat’s water use efficiency and reduce the warming limitation on wheat production.展开更多
基金Ministry of Education Humanities and Social Science Foundation Youth Project“Micro-quantification,Action Mechanism and Impact Research on Financialization of Entity Enterprises”[Grant number.19YJC790106]National Social Science Fund“Mechanism Analysis and Optimization Path Research of Digital Finance Supporting the Im‐provement of Development Efficiency of SMEs”[Grant number.21BJY047]+2 种基金Science and Technology Research Program of Chongqing Education Commission of China:“Optimization Path Research of Or‐ganizational Effectiveness of SOEs in Chongqing Based on Multi-Level Organizational Citizenship Behavior”[Grant number.17SKG036]Chongqing Social Science Planning Major Project“Research on the Technological Progress Path and Countermeasure System of Innovation-driven Manufacturing Upgrade in Chongqing”[Grant num‐ber.2020ZDJJ01]Chongqing Municipal Education Commission Hu‐manities and Social Sciences Research Project“Western Region Finan‐cial Development and Manufacturing Traditional Comparative Advan‐tage Transformation:Efficiency Measurement,Action Mechanism and Research on Spatial Effects”[Grant number.20SKGH040].
文摘The digital economy has become an important driver for stimulating economic growth.The digital economy has now widely penetrated the fields of economy and society,providing new opportunities for the develop‐ment of urban-rural integration.Based on panel data for 30 provinces in China from 2011 to 2020,this study constructed an index system for the integration of the digital economy and the development of urban-rural areas and conducted a systematic measurement analysis.Additionally,we used a two-step system of GMM estimation to analyze the impact of the digital economy on the development of urban-rural integra‐tion.The findings demonstrate the significant imbalance paradox of China’s digital economy development,which is shown in a gradient where the eastern region is higher than the center and the central region is higher than the west.Urban-rural integration levels in China fluctuate and display geographical variance,typically displaying high levels in the east and low levels in the west.Urban-rural integration is significantly encouraged by the digital economy,yet it varies in variability between different areas and dimensions.Addi‐tionally,rural human capital moderates the favorable effects of the digital economy on urban-rural integra‐tion.As a result,in order to achieve the integrated development of urban and rural areas,it is imperative to fully exploit the active role of the digital economy,better support the development of rural revitalization,bridge the“digital divide”between urban and rural development,and build a strong foundation for the for‐mation of a digital urban-rural integrated development pattern with urban and rural areas and common con‐struction and sharing.
基金Supported by the National Natural Science Foundation of China(No.31602152)the Major Agriculture Program of Ningbo(No.2017C110007)the K.C.Wong Magana Fund in Ningbo University.The funding body had no role in the study design,experimental implementation,interpretation of data,or writing of the manuscript。
文摘The wingless-related integration site(WNT)proteins are a family of secreted glycoproteins that are evolutionarily conserved and are believed to be involved in evolution in vertebrates and invertebrates.WNT signaling pathways may be associated with limb regeneration and development in crustaceans.However,the detail mechanisms remain unclear.Therefore,the distribution of WNT4 in the hepatopancreas,muscle,hemocyte,ganglion,heart,eyestalk,gill tissue,and diff erent larvae development stages of the swimming crab(Portunus trituberculatus)were characterized using immunofl uorescence,real-time PCR,and Western blotting.Signifi cant PtWNT4 expression was detected in heart and eyestalk.In addition,PtWNT4 was expressed in all larval stages of P.trituberculatus with a dynamic expression pattern,especially in the eyestalk and other organs in the carapace area.The injection of WNT4 dsRNA into regenerative limbs signifi cantly decreased PtWNT4 mRNA levels in the eyestalk,heart,and muscle,resulting in 1.9-fold,2.2-fold,and 2.7-fold decreases compared with those detected in the group injected with crab saline(P<0.05),respectively,indicating successful gene silencing.Overall,expression analysis on the WNT4 using RNAi provides an insight to its functional mechanism during limb regeneration in P.trituberculatus.The results not only demonstrated the requirement for WNT4 in limb regeneration of Crustaceans,but also suggested its ability to promote larval development at specifi c stages.
基金supported by the China Agriculture Research System of MOF and MARA (CARS-03-19)the National Natural Science Foundation of China (51879267)the Agricultural Science and Technology Innovation Program (ASTIP), Chinese Academy of Agricultural Sciences。
文摘Irrigation methods and nitrogen(N) fertilization modes have complicated impacts on wheat physiology, growth, and development, leading to the regulation of wheat grain yield and quality. However, the optimal water-N combination for drip-irrigated winter wheat remains unclear. A two-year field study was conducted to evaluate the influences of various N-fertigation and water regimes on wheat post-anthesis grain weight variation, yield, grain NPK content, and grain quality. The two irrigation quotas were I_(45)(irrigation when crop evapotranspiration reduced by effective rainfall(ETa-P) reaches 45 mm) and I_(30)(irrigation when ETa-P reaches 30 mm), while the six N application rates were N_(0–100)(100% at jointing/booting), N_(25–75)(25% at sowing and 75% at jointing/booting), N_(50–50)(50% at sowing and 50% at jointing/booting), N_(75–25)(75% at sowing and 25% at jointing/booting), N_(100–0)(100% at sowing), and SRF100(100% of slow-release fertilizer at sowing). The experimental findings showed that post-anthesis grain weight variation, grain yield, grain NPK content, and grain quality were all markedly influenced by the various irrigation schedules and N-fertilization modes. The N_(50–50)treatment was more beneficial for winter wheat post-anthesis grain weight variation than the N_(100–0)and N_(0–100)treatments under the two irrigation quotas and during the two seasons. The highest grain yields of 9.72 and9.94(t ha^(-1)) were obtained with the I_(45)N_(50–50)treatment in 2020–2021 and 2021–2022, respectively. The grain crudeprotein was higher in the I_(45)SRF100treatment during the two seasons. The I_(45)N_(100–0)combination significantly(P<0.05)enhanced the content of grain total starch by 7.30 and 8.23% compared with the I_(45)N_(0–100)and I_(30)N_(0–100)treatments,respectively, during the 2021–2021 season. The I_(45)N_(100–0)treatment significantly(P<0.05) enhanced the content ofgrain total starch concentration by 7.77, 7.62 and 7.88% compared with the I_(45)N_(0–100), I_(30)N_(0–100), and I_(30)N_(25–75)treatments,respectively, in the 2021–2022 season. The principal component analysis(PCA) indicated that the N_(50–50)splitN-fertigation mode could be the optimal choice for farmers during winter wheat production via drip irrigation.
基金Supported by the National Key R&D Program of China(No.2023YFD2401005)the Key R&D Program of Ningbo(No.2022Z059)the K.C.Wong Magna Fund of Ningbo University。
文摘Intraspecific conflict induced by the innate aggressiveness is one of the main reasons for the extremely low survival rate in mud crab Scylla paramamosain aquaculture,which have impeded the sustainable culture of the species.In this study,we first classified and quantified the aggressive behavior,and established a crab aggressive behavior model,laying the foundation for subsequent research on evaluating combat intensity.The contents of 5-hydroxytryptamine(5-HT),dopamine(DA),and cAMP in the hemolymph of the mud crabs before and after fighting were measured by high-performance liquid chromatography-mass spectrometry(HPLC-MS),and the mud crabs exhibited a significant increase of 5-HT(P<0.05),while the DA and cAMP decreased significantly(P<0.05).In addition,we applied EthoVision to examine the changes of the crab behavior after DA administration.After 0.5 h of injection,the movement speed,distance,duration of aggressive behavior,and intensity of aggression in the high concentration DA group were significantly higher than those in the saline injection group and the untreated control group(P<0.05).The results of real-time quantitative polymerase chain reaction(qRT PCR)analysis showed that the expression of DA 1 in the thoracic ganglia of the mud crabs was significantly down-regulated in the DA injection group,and the aggressive behavior was weakened.Conversely,DA1 expression was up-regulated when aggressive behavior was strengthened.Besides,there were significant differences in the expression levels of receptor expression genes including 5-HT1,5-HT2,and crustacean hyperglycemic hormone(CHH)in different tissues,indicating that the alteration of aggressive behavior of the mud crab after injection with different concentrations of DA could be regulated by changes in the expression levels of corresponding receptor genes.Our results contribute to a deeper analysis of the aggressive behavior mechanism of the mud crabs and provide a theoretical basis for reducing fighting-related mortalities in aquaculture.
基金financially supported by the National Natural Science Foundation of China(Nos.52172222 and 51972226)the National Natural Science Foundation of Tianjin City(No.20JCZDJC00570).
文摘The composites prepared by combining lightweight carbon materials with magnetic metals have demonstrated excellent dielectric and magnetic properties,indicating potential applications in the field of electromagnetic wave(EMW)absorption.However,the rational microstructure design and component optimization of these composites in regulating their magnetic-dielectric balance to achieve high-performance EMW absorption remains challenging.Herein,hierarchical yolk-shell Fe@SiO_(2)@NC composites with dual impedance matching layers and dual built-in electric fields were prepared by self-template aggregation and in situ reduction strategies.The introduction of a SiO_(2)wave-transparent layer into a conventional dielectric-magnetic system has resulted in the successful realization of nanoscale precise impedance matching regulation in absorbers,thereby enabling effective ultra-wideband EMW absorption.The dual impedance matching layers of the internal void layer and the SiO_(2)wave-transparent layer facilitate multiple scattering and reflection of EMWs within the absorbers,and the dual built-in electric fields of Fe/SiO_(2)and SiO_(2)/NC can effectively enhance interfacial polarization effect to attenuate EMWs.The predominantly optimized Fe@SiO_(2)@NC-2 exhibits an ultra-wide effective absorption bandwidth(EAB)of 7.10 GHz and an impressive minimum reflection loss(RL_(min))of−64.83 dB,indicating that optimizing the impedance matching via quantitative design can maximize the EMW absorption performance.This work provides a straightforward yet effective approach for constructing multi-component materials with hierarchical yolk-shell structure,which offers valuable insight into the microstructure design and component optimization of innovative EMW absorption materials.
基金This work was supported by the Technology R&D Program of Changsha City(nos.kc1702045 and kq1901145)the Key Technology R&D Program of Hunan Province(nos.2016TP2007,2017TP2006,and 2016TP1014).
文摘Today,resource depletion threatens a number of resource-based cities in China.The ecological security problem caused by the long-term exploitation of natural resources is a key issue to be solved in the development of resource-exhausted cities.Using 23 indicators,this study evaluated the ecological security status and development trends of 21 resource-exhausted cities in China from 2011 to 2017.The results showed that from 2011 to 2015,the overall ecological security of this type of city was low,with over 60%of the cities at an unsafe level.However,ecological security improved rapidly after 2016,and by 2017,all of the cities had reached the critical safety level.The top 10 indicators of ecological security included industrial sulfur dioxide emissions,water supply,agricultural fertilizer application,and forest coverage.These 10 indicators’cumulative contribution to ecological security was 48.3%;among them,reducing industrial sulfur dioxide emissions contributed the most at 5.7%.These findings can help governments better understand the ecological security status of resource-exhausted cities,and it can provide a reference for the allocation of funds and other resources to improve the ecological safety of these cities.
基金Supported by Program for the National Natural Science Foundation of China(No.52071053,U1704253)the Fundamental Research Funds for the Central Universities(DUT20GF111)the China Postdoctoral Science Foundation(2020M670748,2020M680946).
文摘High-temperature electromagnetic(EM) protection materials integrated of multiple EM protection mechanisms and functions are regarded as desirable candidates for solving EM interference over a wide temperature range.In this work,a novel microwave modulator is fabricated by introducing carbonyl iron particles(CIP)/resin into channels of carbonized wood(C-wood).Innovatively,the spaced arrangement of two microwave absorbents not only achieves a synergistic enhancement of magnetic and dielectric losses,but also breaks the translational invariance of EM characteristics in the horizontal direction to obtain multiple phase discontinuities in the frequency range of 8.2-18.0 GHz achieving modulation of reflected wave radiation direction.Accordingly,CIP/C-wood microwave modulator demonstrates the maximum effective bandwidth of 5.2 GHz and the maximum EM protection efficiency over 97% with a thickness of only 1.5 mm in the temperature range 298-673 K.Besides,CIP/C-wood microwave modulator shows stable and low thermal conductivities,as well as monotonic electrical conductivity-temperature characteristics,therefore it can also achieve thermal infrared stealth and working temperature monitoring in wide temperature ranges.This work provides an inspiration for the design of high-temperature EM protection materials with multiple EM protection mechanisms and functions.
文摘Background and Objective(TGA)is a rare life-threatening form of congenital heart disease(CHD)with little known etiology.The recurrence rate in siblings and offspring of TGA patients has been observed higher than general population,implying the contribution of genetic factors.Indeed,family studies identified copy number variants e.g.22q11.2 deletions and point mutations e.g.NKX2-5 underlying genetic susceptibility to TGA or other forms of CHD.However,these genetic variants revealed in family studies are seldom observed in sporadic TGA subjects,indicating a distinct genetic etiology in sporadic TGA that remains to be explored.We sought to explore the genetic etiology of sporadic TGA at different levels including mutations,genes and pathways.
基金supported by the National Key R&D Program of China (2018YFA0209600 and 2017YFA0208300)the National Natural Science Foundation of China (51802302)the Fundamental Research Funds for the Central Universities (WK3430000006)
文摘The interplay between solid electrolytes and electrodes is of vital importance to the performance of allsolid-state Li batteries.Recently,halide superionic conductors have emerged as a new family of high-performance solid electrolytes,but their compatibility with Li metal,i.e.,the anode with the highest theoretical capacity,has not been systematically studied.Here,we investigate the interaction between Li metal and two representative halide solid electrolytes:Li_(3)YCl_(6)and Li_(3)YBr_(6).Both materials are found to form interphases with Li,similar to most solid electrolytes.However,the interphases observed here contain electronic conducting components,which are detrimental to their compatibility with Li.By elucidating this phenomenon,the present study provides guiding principles for improving the Li compatibility of halide solid electrolytes.
基金financially supported by the National Natural Science Foundation of China(Grant No.51879267)the China Agriculture Research System of MOF and MARA(Grant No.CARS-03-19)the Agricultural Science and Technology Innovation Program(ASTIP).
文摘Climate change has limited crop productivity worldwide.Understanding crop response to global climate changes is vital to maintaining agricultural sustainable development.A two-year experiment was conducted to investigate the effects of warming and drought on crop growth and winter wheat yield production.The results showed that both warming and drought shortened the crop growth period,reduced the leaf area index,and increased winter wheat biomass accumulation.Under sufficient water supply conditions,warming would increase photosynthetic and transpiration rates and water use efficiency,while under water deficit conditions,the opposite was observed.Under warming conditions,the grain yield of the water deficit treatment was 8.9%lower than that of the sufficient water supply treatment.Under non-warming conditions,the grain yield of water deficit treatment was 12.4%lower than that of the sufficient water supply.Under the conditions of water-sufficient supply,the grain yield of the warming treatment was 4.4%lower than that of the non-warming treatment,and under the conditions of water deficit,the grain yield of the warming treatment was 1.3%lower than that of the non-warming treatment.Warming tends to decrease wheat growth and grain yield,but sufficient water supply could improve winter wheat’s water use efficiency and reduce the warming limitation on wheat production.
