Objective:To analyze the feasibility of adopting a combined ladder and case teaching method in otolaryngology nursing teaching.Method:Nursing students in the otolaryngology department were selected.According to the ad...Objective:To analyze the feasibility of adopting a combined ladder and case teaching method in otolaryngology nursing teaching.Method:Nursing students in the otolaryngology department were selected.According to the admission time of nursing students,30 nursing students formed a control group(conventional nursing teaching),and 30 nursing students who were admitted later formed an observation group(ladder and case teaching method).The learning performance and teaching effectiveness of nursing students under different teaching methods were analyzed.Result:The academic performance and teaching effectiveness of the observation group were higher than those of the control group(P<0.05).Conclusion:The implementation of the ladder and case teaching method during the teaching of otolaryngology nursing significantly improved the student’s academic performance and teaching effectiveness.This method has great practical value.展开更多
Maize(Zea mays L.)is an indispensable crop worldwide for food,feed,and bioenergy production.Fusarium verticillioides(F.verticillioides)is a widely distributed phytopathogen and incites multiple destructive diseases in...Maize(Zea mays L.)is an indispensable crop worldwide for food,feed,and bioenergy production.Fusarium verticillioides(F.verticillioides)is a widely distributed phytopathogen and incites multiple destructive diseases in maize:seedling blight,stalk rot,ear rot,and seed rot.As a soil-,seed-,and airborne pathogen,F.verticillioides can survive in soil or plant residue and systemically infect maize via roots,contaminated seed,silks,or external wounds,posing a severe threat to maize production and quality.Infection triggers complex immune responses:induction of defense-response genes,changes in reactive oxygen species,plant hormone levels and oxylipins,and alterations in secondary metabolites such as flavonoids,phenylpropanoids,phenolic compounds,and benzoxazinoid defense compounds.Breeding resistant maize cultivars is the preferred approach to reducing F.verticillioides infection and mycotoxin contamination.Reliable phenotyping systems are prerequisites for elucidating the genetic structure and molecular mechanism of maize resistance to F.verticillioides.Although many F.verticillioides resistance genes have been identified by genome-wide association study,linkage analysis,bulkedsegregant analysis,and various omics technologies,few have been functionally validated and applied in molecular breeding.This review summarizes research progress on the infection cycle of F.verticillioides in maize,phenotyping evaluation systems for F.verticillioides resistance,quantitative trait loci and genes associated with F.verticillioides resistance,and molecular mechanisms underlying maize defense against F.verticillioides,and discusses potential avenues for molecular design breeding to improve maize resistance to F.verticillioides.展开更多
Objective:To explore the application effect of microteaching combined with problem-based learning(PBL)teaching mode in teaching clinical nursing interns in otorhinolaryngology department.Methods:A total of 72 nursing ...Objective:To explore the application effect of microteaching combined with problem-based learning(PBL)teaching mode in teaching clinical nursing interns in otorhinolaryngology department.Methods:A total of 72 nursing students who interned in our hospital from June 2022 to February 2023 were selected,and all of them were comprehensively trained in basic theoretical knowledge as well as practical skills before the beginning of their learning tasks.The students were randomly divided into the control group and the experimental group,with 36 students in each group.The control group was taught using the traditional clinical nursing teaching mode,and the experimental group was taught using microteaching combined with the PBL teaching mode,subsequently comparing the differences between the two groups of interns in the degree of mastery of theoretical knowledge,hands-on skills,teamwork ability,patient satisfaction,and other aspects.Results:In terms of mastery of theoretical knowledge,the interns in the experimental group(97.22%)were significantly better than that of the control group(75.00%)(P<0.05);the interns in the experimental group had significantly better practical skills(77.78%)than that of the control group(55.56%)(P<0.05);the interns in the experimental group had significantly better teamwork ability than the control group(P<0.05);through the questionnaire survey,it was found that students’satisfaction with teaching in the experimental group(97.22%)was also significantly higher than that in the control group(75.00%)(P<0.05).Conclusion:The application of microteaching combined with PBL teaching mode in the teaching of clinical nursing interns in otorhinolaryngology department achieved significant results.It can not only improve the professional knowledge and application ability of nursing students,but also cultivate their independent thinking,problem-solving skill,as well as teamwork ability.It can also improve the teaching quality and patient satisfaction,and contribute positively to the development of medical education.展开更多
Since forty years of reform and opening up,China's rural landscape has undergone tremendous changes,and agricultural production manner is obviously improved,while farmers' living level is rose significantly.Ru...Since forty years of reform and opening up,China's rural landscape has undergone tremendous changes,and agricultural production manner is obviously improved,while farmers' living level is rose significantly.Rural land contracting and management right system plays a vital role in promoting rural economic and social development in China.In this paper,farmers under the background of the transfer of rural land contracting and management right are taken as research objects,and the difference of different types of farmers under the willingness of land transfer is analyzed.Finally,corresponding reform assumptions are proposed for transfer willingness of different types of farmers.展开更多
With the development of the times,the contradiction between human living and the natural environment becomes increasingly prominent.People pay more and more attention to the protection of the natural environment while...With the development of the times,the contradiction between human living and the natural environment becomes increasingly prominent.People pay more and more attention to the protection of the natural environment while improving the living standard.While,the emergence of the ecological roof can greatly improve the urban ecological environment and make full use of the architectural space.On the premise of analyzing the current status and significance of research on the ecological roof,this paper puts forward some ideas about the research on the design of the ecological roof with intelligent management system which can be used as a reference for the design of the ecological roof in the future,based on giving full consideration to the factors of ecological energy-saving,environmental protection,economic development,etc.,and summarizing the shortcomings of the traditional ecological roof.展开更多
The China National Climate Center and National Centers for Environmental Prediction data were used in this work. Using the knowledge of synoptic principles and synoptic analysis, the rain and snow weather process in t...The China National Climate Center and National Centers for Environmental Prediction data were used in this work. Using the knowledge of synoptic principles and synoptic analysis, the rain and snow weather process in the middle and east of China from December 28 to 30, 2020 was analyzed. The results show that: 1) This weather process was a large-scale precipitation process. Affected by the cold wave, the temperature drops sharply, and the temperature in many places dropped below the extreme value, accompanied by strong winds. 2) This process is mainly caused by the eastward movement of the upper-level trough leading the cold air southward to intersect with the warm and wet air, and the shear thread in the lower layer cooperates. 3) The cold air is from the ocean east of Novaya Zemlya. 4) From the evolution trend of 500 hPa geopotential height field and ground pressure field, the cold surge process belongs to the type of transverse trough to vertical.展开更多
Anti-icing coatings on outdoor infrastructures inevitably suffer from mechanical injuries in numerous icing scenarios such as hailstorms,sandstorms,impacts of foreign objects,and icing–deicing cycles.Herein,the mecha...Anti-icing coatings on outdoor infrastructures inevitably suffer from mechanical injuries in numerous icing scenarios such as hailstorms,sandstorms,impacts of foreign objects,and icing–deicing cycles.Herein,the mechanisms of surface-defect-induced icing are clarified.At the defects,water molecules exhibit stronger adsorption and the heat transfer rate increases,accelerating the condensation of water vapor as well as ice nucleation and propagation.Moreover,the ice–defect interlocking structure increases the ice adhesion strength.Thus,a self-healing(at−20℃)antifreeze-protein(AFP)-inspired anti-icing coating is developed.The coating is based on a design that mimics the ice-binding and non-ice-binding sites in AFPs.It enables the coating to markedly inhibit ice nucleation(nucleation temperature<−29.4℃),prevent ice propagation(propagation rate<0.00048 cm^(2)/s),and reduce ice adhesion on the surface(adhesion strength<38.9 kPa).More importantly,the coating can also autonomously self-heal at−20℃,as a result of multiple dynamic bonds in its structure,to inhibit defect-induced icing processes.The healed coating sustains high anti-icing and deicing performance even under various extreme conditions.This work reveals the in-depth mechanism of defect-induced ice formation as well as adhesion,and proposes a self-healing anti-icing coating for outdoor infrastructures.展开更多
The utilization of abundant and renewable biomass to fabricate advanced functional materials is considered a promising route for environmental applications.Herein,Lignin-based porous carbon with layered graphene-like ...The utilization of abundant and renewable biomass to fabricate advanced functional materials is considered a promising route for environmental applications.Herein,Lignin-based porous carbon with layered graphene-like structure(LPC)is successfully synthesized and applied to efficiently remove Pb(Ⅱ)and Cd(Ⅱ).The as-synthesized LPC materials are systematically characterized and these results show that LPC has a porous graphene-like structure,facilitating the diffusion and immobilization of heavy metal ions.The influence of different reaction parameters(solution pH,initial concentration of metal ions,contact time and adsorbent amount)on the adsorption performance is investigated in details.The results demonstrate that LPC can achieve superior adsorption capacities of 250.5 mg·g^-1 for Pb(Ⅱ)and 126.4 mg·g^-1 for Cd(Ⅱ),which are far superior to the previously reported adsorbents.Pseudo-second order kinetics model and Freundlich isotherm model describe the adsorption process well.Furthermore,the exhausted LPC can be regenerated easily and exhibits the removal efficiency of 96%and 92%for Pb(Ⅱ)and Cd(Ⅱ)after five continuous runs,respectively.This study shows a sustainable strategy for the design of porous carbon material from na?ve biomass and highlights the great potential in wastewater treatment.展开更多
Circadian rhythm is involved in the development and diseases of many tissues.However,as an essential environmental regulating factor,its effect on amelogenesis has not been fully elucidated.The present study aims to i...Circadian rhythm is involved in the development and diseases of many tissues.However,as an essential environmental regulating factor,its effect on amelogenesis has not been fully elucidated.The present study aims to investigate the correlation between circadian rhythm and ameloblast differentiation and to explore the mechanism by which circadian genes regulate ameloblast differentiation.Circadian disruption models were constructed in mice for in vivo experiments.An ameloblast-lineage cell(ALC)line was used for in vitro studies.As essential molecules of the circadian system,Bmal1 and Per2 exhibited circadian expression in ALCs.Circadian disruption mice showed reduced amelogenin(AMELX)expression and enamel matrix secretion and downregulated expression of BMAL1,PER2,PPARγ,phosphorylated AKT1 andβ-catenin,cytokeratin-14 and F-actin in ameloblasts.According to previous findings and our study,BMAL1 positively regulated PER2.Therefore,the present study focused on PER2-mediated ameloblast differentiation and enamel formation.Per2 knockdown decreased the expression of AMELX,PPARγ,phosphorylated AKT1 andβ-catenin,promoted nuclearβ-catenin accumulation,inhibited mineralization and altered the subcellular localization of E-cadherin in ALCs.Overexpression of PPARγpartially reversed the above results in Per2-knockdown ALCs.Furthermore,in in vivo experiments,the length of incisor eruption was significantly decreased in the circadian disturbance group compared to that in the control group,which was rescued by using a PPARγagonist in circadian disturbance mice.In conclusion,through regulation of the PPARγ/AKT1/β-catenin signalling axis,PER2 played roles in amelogenin expression,cell junctions and arrangement,enamel matrix secretion and mineralization during ameloblast differentiation,which exert effects on enamel formation.展开更多
Safety resilient city is a frontier concept of urban safety development and a hot topic in the field of urban safety research. In this paper, the relevant research results of domestic and foreign scholars are reviewed...Safety resilient city is a frontier concept of urban safety development and a hot topic in the field of urban safety research. In this paper, the relevant research results of domestic and foreign scholars are reviewed from the perspectives of concepts and models, the evaluation indicator system of urban safety resilience is compared in terms of risk types, evaluation objects, evaluation dimensions and quantitative methods, and the development of international standards for resilient cities is discussed. Based on the literature review, the connotation of the triangular theoretical model of urban safety resilience is explained, and an urban safety resilience evaluation index system applicable to Chinese cities is proposed, which provides support for the development of the national standard “Guide for safety resilient city evaluation” (GB/T 40947-2021). It is applied to six representative cities as examples for evaluation to explore the direction of Chinese urban safety resilience improvement. The pathway for improving the safety resilience of Chinese cities is discussed.展开更多
Since lithium iron phosphate cathode material does not contain high-value metals other than lithium,it is therefore necessary to strike a balance between recovery efficiency and economic benefits in the recycling of w...Since lithium iron phosphate cathode material does not contain high-value metals other than lithium,it is therefore necessary to strike a balance between recovery efficiency and economic benefits in the recycling of waste lithium iron phosphate cathode materials.Here,we describe a selective recovery process that can achieve economically efficient recovery and an acceptable lithium leaching yield.Adjusting the acid concentration and amount of oxidant enables selective recovery of lithium ions.Iron is retained in the leaching residue as iron phosphate,which is easy to recycle.The effects of factors such as acid concentration,acid dosage,amount of oxidant,and reaction temperature on the leaching of lithium and iron are comprehensively explored,and the mechanism of selective leaching is clarified.This process greatly reduces the cost of processing equipment and chemicals.This increases the potential industrial use of this process and enables the green and efficient recycling of waste lithium iron phosphate cathode materials in the future.展开更多
Network representation learning algorithms,which aim at automatically encoding graphs into low-dimensional vector representations with a variety of node similarity definitions,have a wide range of downstream applicati...Network representation learning algorithms,which aim at automatically encoding graphs into low-dimensional vector representations with a variety of node similarity definitions,have a wide range of downstream applications.Most existing methods either have low accuracies in downstream tasks or a very limited application field,such as article classification in citation networks.In this paper,we propose a novel network representation method,named Link Prediction based Network Representation(LPNR),which generalizes the latest graph neural network and optimizes a carefully designed objective function that preserves linkage structures.LPNR can not only learn meaningful node representations that achieve competitive accuracy in node centrality measurement and community detection but also achieve high accuracy in the link prediction task.Experiments prove the effectiveness of LPNR on three real-world networks.With the mini-batch and fixed sampling strategy,LPNR can learn the embedding of large graphs in a few hours.展开更多
Asymmetrical voltage swells during recovery of a short-circuit fault lead to fluctuations in the dc-link voltage of a renewable energy conversion system(RECS),and may induce reversed power flow and even trip the RECS....Asymmetrical voltage swells during recovery of a short-circuit fault lead to fluctuations in the dc-link voltage of a renewable energy conversion system(RECS),and may induce reversed power flow and even trip the RECS. This paper studies characteristics of both typical causes resulting in the practical asymmetrical voltage swell and the voltage at the point of common coupling(PCC)during the fault recovery. As analyzed, the fault recovery process can be divided into two continuous periods in which different control strategies have to be applied. Also protective measures are necessary in the transient period of the process. Additionally, the asymmetrical high-voltage ride-through capability and the controllability criteria of the RECS are analyzed based on eliminating the fluctuations. Furthermore, an asymmetrical control scheme is proposed to maintain the controllability of the RECS and ride through the entire recovery process. As verified by the simulation, the scheme can promise the RECS to deal with the practical fault recovery period and mitigate the dc-link voltage fluctuations, which improves the reliability of the RECS and the power system.展开更多
文摘Objective:To analyze the feasibility of adopting a combined ladder and case teaching method in otolaryngology nursing teaching.Method:Nursing students in the otolaryngology department were selected.According to the admission time of nursing students,30 nursing students formed a control group(conventional nursing teaching),and 30 nursing students who were admitted later formed an observation group(ladder and case teaching method).The learning performance and teaching effectiveness of nursing students under different teaching methods were analyzed.Result:The academic performance and teaching effectiveness of the observation group were higher than those of the control group(P<0.05).Conclusion:The implementation of the ladder and case teaching method during the teaching of otolaryngology nursing significantly improved the student’s academic performance and teaching effectiveness.This method has great practical value.
基金the National Natural Science Foundation of China(32201787,32201793)the Innovation Special Program of Henan Agricultural University for Science and Technology(30501044)the Special Support Fund for High-Level Talents of Henan Agricultural University(30501302).
文摘Maize(Zea mays L.)is an indispensable crop worldwide for food,feed,and bioenergy production.Fusarium verticillioides(F.verticillioides)is a widely distributed phytopathogen and incites multiple destructive diseases in maize:seedling blight,stalk rot,ear rot,and seed rot.As a soil-,seed-,and airborne pathogen,F.verticillioides can survive in soil or plant residue and systemically infect maize via roots,contaminated seed,silks,or external wounds,posing a severe threat to maize production and quality.Infection triggers complex immune responses:induction of defense-response genes,changes in reactive oxygen species,plant hormone levels and oxylipins,and alterations in secondary metabolites such as flavonoids,phenylpropanoids,phenolic compounds,and benzoxazinoid defense compounds.Breeding resistant maize cultivars is the preferred approach to reducing F.verticillioides infection and mycotoxin contamination.Reliable phenotyping systems are prerequisites for elucidating the genetic structure and molecular mechanism of maize resistance to F.verticillioides.Although many F.verticillioides resistance genes have been identified by genome-wide association study,linkage analysis,bulkedsegregant analysis,and various omics technologies,few have been functionally validated and applied in molecular breeding.This review summarizes research progress on the infection cycle of F.verticillioides in maize,phenotyping evaluation systems for F.verticillioides resistance,quantitative trait loci and genes associated with F.verticillioides resistance,and molecular mechanisms underlying maize defense against F.verticillioides,and discusses potential avenues for molecular design breeding to improve maize resistance to F.verticillioides.
文摘Objective:To explore the application effect of microteaching combined with problem-based learning(PBL)teaching mode in teaching clinical nursing interns in otorhinolaryngology department.Methods:A total of 72 nursing students who interned in our hospital from June 2022 to February 2023 were selected,and all of them were comprehensively trained in basic theoretical knowledge as well as practical skills before the beginning of their learning tasks.The students were randomly divided into the control group and the experimental group,with 36 students in each group.The control group was taught using the traditional clinical nursing teaching mode,and the experimental group was taught using microteaching combined with the PBL teaching mode,subsequently comparing the differences between the two groups of interns in the degree of mastery of theoretical knowledge,hands-on skills,teamwork ability,patient satisfaction,and other aspects.Results:In terms of mastery of theoretical knowledge,the interns in the experimental group(97.22%)were significantly better than that of the control group(75.00%)(P<0.05);the interns in the experimental group had significantly better practical skills(77.78%)than that of the control group(55.56%)(P<0.05);the interns in the experimental group had significantly better teamwork ability than the control group(P<0.05);through the questionnaire survey,it was found that students’satisfaction with teaching in the experimental group(97.22%)was also significantly higher than that in the control group(75.00%)(P<0.05).Conclusion:The application of microteaching combined with PBL teaching mode in the teaching of clinical nursing interns in otorhinolaryngology department achieved significant results.It can not only improve the professional knowledge and application ability of nursing students,but also cultivate their independent thinking,problem-solving skill,as well as teamwork ability.It can also improve the teaching quality and patient satisfaction,and contribute positively to the development of medical education.
基金Supported by On-campus Selection Match Program of the 16th "Challenge Cup" College Students'Extracurricular Academic Science and Technology Works Competition of Jiangxi Normal University
文摘Since forty years of reform and opening up,China's rural landscape has undergone tremendous changes,and agricultural production manner is obviously improved,while farmers' living level is rose significantly.Rural land contracting and management right system plays a vital role in promoting rural economic and social development in China.In this paper,farmers under the background of the transfer of rural land contracting and management right are taken as research objects,and the difference of different types of farmers under the willingness of land transfer is analyzed.Finally,corresponding reform assumptions are proposed for transfer willingness of different types of farmers.
文摘With the development of the times,the contradiction between human living and the natural environment becomes increasingly prominent.People pay more and more attention to the protection of the natural environment while improving the living standard.While,the emergence of the ecological roof can greatly improve the urban ecological environment and make full use of the architectural space.On the premise of analyzing the current status and significance of research on the ecological roof,this paper puts forward some ideas about the research on the design of the ecological roof with intelligent management system which can be used as a reference for the design of the ecological roof in the future,based on giving full consideration to the factors of ecological energy-saving,environmental protection,economic development,etc.,and summarizing the shortcomings of the traditional ecological roof.
文摘The China National Climate Center and National Centers for Environmental Prediction data were used in this work. Using the knowledge of synoptic principles and synoptic analysis, the rain and snow weather process in the middle and east of China from December 28 to 30, 2020 was analyzed. The results show that: 1) This weather process was a large-scale precipitation process. Affected by the cold wave, the temperature drops sharply, and the temperature in many places dropped below the extreme value, accompanied by strong winds. 2) This process is mainly caused by the eastward movement of the upper-level trough leading the cold air southward to intersect with the warm and wet air, and the shear thread in the lower layer cooperates. 3) The cold air is from the ocean east of Novaya Zemlya. 4) From the evolution trend of 500 hPa geopotential height field and ground pressure field, the cold surge process belongs to the type of transverse trough to vertical.
基金the National Key Research and Development Program of China(2022YFC2104800 and 2021YFC2100800)the National Natural Science Foundation of China(22078238,21908160,and 21961132005).
文摘Anti-icing coatings on outdoor infrastructures inevitably suffer from mechanical injuries in numerous icing scenarios such as hailstorms,sandstorms,impacts of foreign objects,and icing–deicing cycles.Herein,the mechanisms of surface-defect-induced icing are clarified.At the defects,water molecules exhibit stronger adsorption and the heat transfer rate increases,accelerating the condensation of water vapor as well as ice nucleation and propagation.Moreover,the ice–defect interlocking structure increases the ice adhesion strength.Thus,a self-healing(at−20℃)antifreeze-protein(AFP)-inspired anti-icing coating is developed.The coating is based on a design that mimics the ice-binding and non-ice-binding sites in AFPs.It enables the coating to markedly inhibit ice nucleation(nucleation temperature<−29.4℃),prevent ice propagation(propagation rate<0.00048 cm^(2)/s),and reduce ice adhesion on the surface(adhesion strength<38.9 kPa).More importantly,the coating can also autonomously self-heal at−20℃,as a result of multiple dynamic bonds in its structure,to inhibit defect-induced icing processes.The healed coating sustains high anti-icing and deicing performance even under various extreme conditions.This work reveals the in-depth mechanism of defect-induced ice formation as well as adhesion,and proposes a self-healing anti-icing coating for outdoor infrastructures.
基金supported by National Ten Thousand Plan Young Top-notch Talent PlanNational Key R&D Program of China (2018YFD0800700)+3 种基金National Natural Science Foundation of China (21776324)Science and Technology Planning Project of Guangdong Province (2014A050503032)Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology (2018K02)Hundred Talent Plan (201602) from Sun Yat-sen University
文摘The utilization of abundant and renewable biomass to fabricate advanced functional materials is considered a promising route for environmental applications.Herein,Lignin-based porous carbon with layered graphene-like structure(LPC)is successfully synthesized and applied to efficiently remove Pb(Ⅱ)and Cd(Ⅱ).The as-synthesized LPC materials are systematically characterized and these results show that LPC has a porous graphene-like structure,facilitating the diffusion and immobilization of heavy metal ions.The influence of different reaction parameters(solution pH,initial concentration of metal ions,contact time and adsorbent amount)on the adsorption performance is investigated in details.The results demonstrate that LPC can achieve superior adsorption capacities of 250.5 mg·g^-1 for Pb(Ⅱ)and 126.4 mg·g^-1 for Cd(Ⅱ),which are far superior to the previously reported adsorbents.Pseudo-second order kinetics model and Freundlich isotherm model describe the adsorption process well.Furthermore,the exhausted LPC can be regenerated easily and exhibits the removal efficiency of 96%and 92%for Pb(Ⅱ)and Cd(Ⅱ)after five continuous runs,respectively.This study shows a sustainable strategy for the design of porous carbon material from na?ve biomass and highlights the great potential in wastewater treatment.
基金the National Natural Science Foundation of China,grant number No.81670976.
文摘Circadian rhythm is involved in the development and diseases of many tissues.However,as an essential environmental regulating factor,its effect on amelogenesis has not been fully elucidated.The present study aims to investigate the correlation between circadian rhythm and ameloblast differentiation and to explore the mechanism by which circadian genes regulate ameloblast differentiation.Circadian disruption models were constructed in mice for in vivo experiments.An ameloblast-lineage cell(ALC)line was used for in vitro studies.As essential molecules of the circadian system,Bmal1 and Per2 exhibited circadian expression in ALCs.Circadian disruption mice showed reduced amelogenin(AMELX)expression and enamel matrix secretion and downregulated expression of BMAL1,PER2,PPARγ,phosphorylated AKT1 andβ-catenin,cytokeratin-14 and F-actin in ameloblasts.According to previous findings and our study,BMAL1 positively regulated PER2.Therefore,the present study focused on PER2-mediated ameloblast differentiation and enamel formation.Per2 knockdown decreased the expression of AMELX,PPARγ,phosphorylated AKT1 andβ-catenin,promoted nuclearβ-catenin accumulation,inhibited mineralization and altered the subcellular localization of E-cadherin in ALCs.Overexpression of PPARγpartially reversed the above results in Per2-knockdown ALCs.Furthermore,in in vivo experiments,the length of incisor eruption was significantly decreased in the circadian disturbance group compared to that in the control group,which was rescued by using a PPARγagonist in circadian disturbance mice.In conclusion,through regulation of the PPARγ/AKT1/β-catenin signalling axis,PER2 played roles in amelogenin expression,cell junctions and arrangement,enamel matrix secretion and mineralization during ameloblast differentiation,which exert effects on enamel formation.
基金This work was supported by the National Natural Science Foundation of China(Grant No.72091512)the National Key R&D Program of China(Grant No.2018YFC0809900).
文摘Safety resilient city is a frontier concept of urban safety development and a hot topic in the field of urban safety research. In this paper, the relevant research results of domestic and foreign scholars are reviewed from the perspectives of concepts and models, the evaluation indicator system of urban safety resilience is compared in terms of risk types, evaluation objects, evaluation dimensions and quantitative methods, and the development of international standards for resilient cities is discussed. Based on the literature review, the connotation of the triangular theoretical model of urban safety resilience is explained, and an urban safety resilience evaluation index system applicable to Chinese cities is proposed, which provides support for the development of the national standard “Guide for safety resilient city evaluation” (GB/T 40947-2021). It is applied to six representative cities as examples for evaluation to explore the direction of Chinese urban safety resilience improvement. The pathway for improving the safety resilience of Chinese cities is discussed.
基金supported by the National Natural Science Foundation of China(Grant Nos.22125802,and 22078010)Beijing Natural Science Foundation(Grant No.2222017)Big Science Project from BUCT(Grant No.XK180301)。
文摘Since lithium iron phosphate cathode material does not contain high-value metals other than lithium,it is therefore necessary to strike a balance between recovery efficiency and economic benefits in the recycling of waste lithium iron phosphate cathode materials.Here,we describe a selective recovery process that can achieve economically efficient recovery and an acceptable lithium leaching yield.Adjusting the acid concentration and amount of oxidant enables selective recovery of lithium ions.Iron is retained in the leaching residue as iron phosphate,which is easy to recycle.The effects of factors such as acid concentration,acid dosage,amount of oxidant,and reaction temperature on the leaching of lithium and iron are comprehensively explored,and the mechanism of selective leaching is clarified.This process greatly reduces the cost of processing equipment and chemicals.This increases the potential industrial use of this process and enables the green and efficient recycling of waste lithium iron phosphate cathode materials in the future.
基金support from the program of the China Scholarships Council(No.201806040107)the Fundamental Research Funds for the Central Universities,the National Natural Science Foundation of China(Nos.61673070 and 61903020)the BUCT Talent Start-up Fund(No.BUCTRC 201825).We acknowledge the help from the Swarma Club.
文摘Network representation learning algorithms,which aim at automatically encoding graphs into low-dimensional vector representations with a variety of node similarity definitions,have a wide range of downstream applications.Most existing methods either have low accuracies in downstream tasks or a very limited application field,such as article classification in citation networks.In this paper,we propose a novel network representation method,named Link Prediction based Network Representation(LPNR),which generalizes the latest graph neural network and optimizes a carefully designed objective function that preserves linkage structures.LPNR can not only learn meaningful node representations that achieve competitive accuracy in node centrality measurement and community detection but also achieve high accuracy in the link prediction task.Experiments prove the effectiveness of LPNR on three real-world networks.With the mini-batch and fixed sampling strategy,LPNR can learn the embedding of large graphs in a few hours.
基金supported by National Natural Science Foundation of China(NSFC)(No.U1510208,No.61273045,No.51361135705)National High Technology Research and Development Program of China(No.2012AA050217)Grants from Beijing Higher Education Young Elite Teacher Project
文摘Asymmetrical voltage swells during recovery of a short-circuit fault lead to fluctuations in the dc-link voltage of a renewable energy conversion system(RECS),and may induce reversed power flow and even trip the RECS. This paper studies characteristics of both typical causes resulting in the practical asymmetrical voltage swell and the voltage at the point of common coupling(PCC)during the fault recovery. As analyzed, the fault recovery process can be divided into two continuous periods in which different control strategies have to be applied. Also protective measures are necessary in the transient period of the process. Additionally, the asymmetrical high-voltage ride-through capability and the controllability criteria of the RECS are analyzed based on eliminating the fluctuations. Furthermore, an asymmetrical control scheme is proposed to maintain the controllability of the RECS and ride through the entire recovery process. As verified by the simulation, the scheme can promise the RECS to deal with the practical fault recovery period and mitigate the dc-link voltage fluctuations, which improves the reliability of the RECS and the power system.