Background:Parents of children with autism are susceptible to parenting burnout due to tremendous parenting burden and parenting challenges.Parenting burnout has a detrimental effect on both children with autism and t...Background:Parents of children with autism are susceptible to parenting burnout due to tremendous parenting burden and parenting challenges.Parenting burnout has a detrimental effect on both children with autism and their parents.However,the underlying mechanisms that lead to parenting burnout remain unclear.This study aimed to investigate the relationship between parenting stress and parenting burnout,along with the serial mediation effect of social support and coping strategies in the context of families with autistic children.Methods:We conducted a cross-sectional study in 231 parents of autistic children in four autism facilities located in central Hubei province.Data were collected through the Parental Stress Index,Social Support Rating Scale,Simplified Coping Strategies Questionnaire,and Caregiver Burnout Assessment Questionnaire.Results:Parenting stress and burnout status were:72.3%of parents reported high-stress levels,16.9%experienced risks for parenting burnout,and 19.9%were currently experiencing burnout.Both social support and coping strategies played partial mediating roles in the relationship between parental stress and burnout,forming a serial mediation effect.Conclusion:Parenting stress is a risk factor for parenting burnout.Social support and coping strategies play a chain mediating role between parenting stress and parenting burnout,which may act as the underlying mechanisms.The study offers insights into potential intervention points for reducing parenting burnout.Future efforts are needed to devote to parenting stress,social support and coping strategy to enhance the psychological well-being of parents with autistic children.展开更多
Agritourism is a modern agricultural model,which is combination of agriculture and rural tourism. Its goal is to carry on the culture of farming and achieve economic efficiency. To achieve this goal,brand building is ...Agritourism is a modern agricultural model,which is combination of agriculture and rural tourism. Its goal is to carry on the culture of farming and achieve economic efficiency. To achieve this goal,brand building is very important. However,most companies have the same goods and services in the development process. Managers lack brand awareness,and enterprises lack core competitiveness. To solve these problems,the agritourism enterprises must change their management concepts,establish brand awareness,improve quality of service,increase the cultural connotation of products and services,and strengthen marketing efforts to achieve the overall improvement of modern agricultural brand.展开更多
This paper mainly introduces the longitudinal transmission mechanism of urban vegetable prices in Chongqing area. On the basis of the supply chain theory,the " farm price- wholesale price- retail price" of v...This paper mainly introduces the longitudinal transmission mechanism of urban vegetable prices in Chongqing area. On the basis of the supply chain theory,the " farm price- wholesale price- retail price" of vegetables in Chongqing has been identified as the research object. Through statistical analysis,it is found that the above three types of price show a modest annual fluctuation of 7- 12% from 2008 to2013. Later,the paper focuses on the empirical research on the weekly price data in 2013 applying the co-integration theory,which reveals that the farm price of vegetables is largely influenced by themselves; the wholesale price of vegetables is mainly affected by their own price,the production price and the retail price of the earlier stage without the current influence of the production price; and the retail price of vegetables is also affected by their own price,but is not affected by the their current local price and the wholesale price. Vegetable prices have shown an obvious positive transmission mechanism in the links from production to retail,but the feedback effect of retail on production is not brought into play.展开更多
Controlling the direction of ferromagnetism and antiferromagnetism by an electric field in single-phase multiferroics will open the door to the next generation of devices for spintronics and electronics.The typical ma...Controlling the direction of ferromagnetism and antiferromagnetism by an electric field in single-phase multiferroics will open the door to the next generation of devices for spintronics and electronics.The typical magnetoelectric coupling such as the linear magnetoelectric effect is very weak in type-I multiferroics and therefore the magnetoelectric switching is rarely achieved.Here,using firstprinciples simulations,we propose a magnetoelectric switching mechanism to achieve such highly desired control in orthorhombic multiferroics.展开更多
Charged ferroelectric domain walls are fascinating electrical topological defects that can exhibit unusual properties.Here,in the search for novel phenomena,we perform and analyze first-principles calculations to inve...Charged ferroelectric domain walls are fascinating electrical topological defects that can exhibit unusual properties.Here,in the search for novel phenomena,we perform and analyze first-principles calculations to investigate the effect of domain width on properties of domains with charged walls in the photovoltaic material consisting of methylammonium lead iodide hybrid perovskite.We report that such domains are stable and have rather low domain wall energy for any investigated width(that is,up to 13 lattice constants).Increasing the domain width first linearly decreases the electronic band gap from≃1.4 eV to about zero(which therefore provides an efficient band-gap engineering),before the system undergoes an insulator-to-metal transition and then remains metallic(with both the tail-to-tail and head-to-head domain walls being conductive)for the largest widths.All these results can be understood in terms of:(i)components of polarization along the normal of the domain walls being small in magnitude;(ii)an internal electric field that is basically independent of the domain width;and(iii)rather negligible charge transfer between walls.These findings deepen the knowledge of charged ferroelectric domain walls and can further broaden their potential for applications,particularly in the context of halide perovskites for photovoltaics.展开更多
The effects of temperature on the convecsion of Li2 CO3 Co LiOH in a Ca（OH）2 suspension were investigated. Li2CO3 microplates were used as the Li source. The results showed that Li2CO3 was converted to LiOH via in s...The effects of temperature on the convecsion of Li2 CO3 Co LiOH in a Ca（OH）2 suspension were investigated. Li2CO3 microplates were used as the Li source. The results showed that Li2CO3 was converted to LiOH via in situ ion-exchange and dissolution-precipitation routes. The formation of mixed CaxLiz-2xCO3 inter- mediate species confirmed that at 25℃ need/e-like CaCO3 was formed heterogeneously on the Li2CO3 surface via in situ ion-exchange. At 60-100℃, isolated CaCO3 agglomerates were formed homogeneously via dissolution-precipitation. Temperature increases accelerated the dissolution and conversion of Li2 CO3 to LiOH, producing solutions with high [CO32-1][Ca^2＋] ratios; this favored homogeneous precipitation of isolated CaCO3 agglomerates,展开更多
In 1861,Maxwell conceived the idea of the displacement current,which then made laws of electrodynamics more complete and also resulted in the realization of devices exploiting such displacement current.Interestingly,i...In 1861,Maxwell conceived the idea of the displacement current,which then made laws of electrodynamics more complete and also resulted in the realization of devices exploiting such displacement current.Interestingly,it is presently unknown if such displacement current can result in large intrinsic ac current in ferroic systems possessing domains,despite the flurry of recent activities that have been devoted to domains and their corresponding conductivity in these compounds.Here,we report firstprinciples-based atomistic simulations that predict that the transverse(polarization-related)displacement currents of 71°and 109°domains in the prototypical BiFeO_(3) multiferroic material are significant at the walls of such domains and in the GHz regime,and,in fact,result in currents that are at least of the same order of magnitude than previously reported dc currents(that are likely extrinsic in nature and due to electrons).Such large,localized and intrinsic ac currents are found to originate from low-frequency vibrations at the domain walls,and may open the door to the design of novel devices functioning in the GHz or THz range and in which currents would be confined within the domain wall.展开更多
基金supported by the Humanities and Social Sciences Research Planning Fund of Chinese Ministry of Education(22YJAZH150).
文摘Background:Parents of children with autism are susceptible to parenting burnout due to tremendous parenting burden and parenting challenges.Parenting burnout has a detrimental effect on both children with autism and their parents.However,the underlying mechanisms that lead to parenting burnout remain unclear.This study aimed to investigate the relationship between parenting stress and parenting burnout,along with the serial mediation effect of social support and coping strategies in the context of families with autistic children.Methods:We conducted a cross-sectional study in 231 parents of autistic children in four autism facilities located in central Hubei province.Data were collected through the Parental Stress Index,Social Support Rating Scale,Simplified Coping Strategies Questionnaire,and Caregiver Burnout Assessment Questionnaire.Results:Parenting stress and burnout status were:72.3%of parents reported high-stress levels,16.9%experienced risks for parenting burnout,and 19.9%were currently experiencing burnout.Both social support and coping strategies played partial mediating roles in the relationship between parental stress and burnout,forming a serial mediation effect.Conclusion:Parenting stress is a risk factor for parenting burnout.Social support and coping strategies play a chain mediating role between parenting stress and parenting burnout,which may act as the underlying mechanisms.The study offers insights into potential intervention points for reducing parenting burnout.Future efforts are needed to devote to parenting stress,social support and coping strategy to enhance the psychological well-being of parents with autistic children.
文摘Agritourism is a modern agricultural model,which is combination of agriculture and rural tourism. Its goal is to carry on the culture of farming and achieve economic efficiency. To achieve this goal,brand building is very important. However,most companies have the same goods and services in the development process. Managers lack brand awareness,and enterprises lack core competitiveness. To solve these problems,the agritourism enterprises must change their management concepts,establish brand awareness,improve quality of service,increase the cultural connotation of products and services,and strengthen marketing efforts to achieve the overall improvement of modern agricultural brand.
基金Supported by Western Project of Ministry of Education(13XJC630006)Young Scholar Project of National Social Science Foundation"Cooperative Path for Evolution of Social Network and Advance of Farmers Starting an Undertaking in Transformation Period"(14CGL029)
文摘This paper mainly introduces the longitudinal transmission mechanism of urban vegetable prices in Chongqing area. On the basis of the supply chain theory,the " farm price- wholesale price- retail price" of vegetables in Chongqing has been identified as the research object. Through statistical analysis,it is found that the above three types of price show a modest annual fluctuation of 7- 12% from 2008 to2013. Later,the paper focuses on the empirical research on the weekly price data in 2013 applying the co-integration theory,which reveals that the farm price of vegetables is largely influenced by themselves; the wholesale price of vegetables is mainly affected by their own price,the production price and the retail price of the earlier stage without the current influence of the production price; and the retail price of vegetables is also affected by their own price,but is not affected by the their current local price and the wholesale price. Vegetable prices have shown an obvious positive transmission mechanism in the links from production to retail,but the feedback effect of retail on production is not brought into play.
基金the National Key R&D Program of China(Grants No.2022YFB3807601 and No.2020YFA0711504)the National Natural Science Foundation of China(Grants No.12274201,No.51721001,No.12104416,and No.52232001)+2 种基金L.B.thanks the Office of Naval Research(Grant No.N00014-21-1-2086)the Vannevar Bush Faculty Fellowship(VBFF)Grant No.N00014-20-1-2834 from the Department of Defenseis thankful for support from the MonArk Quantum Foundry supported by the National Science Foundation Q-AMASE-i program under NSF Award No.DMR-1906383.
文摘Controlling the direction of ferromagnetism and antiferromagnetism by an electric field in single-phase multiferroics will open the door to the next generation of devices for spintronics and electronics.The typical magnetoelectric coupling such as the linear magnetoelectric effect is very weak in type-I multiferroics and therefore the magnetoelectric switching is rarely achieved.Here,using firstprinciples simulations,we propose a magnetoelectric switching mechanism to achieve such highly desired control in orthorhombic multiferroics.
基金Y.Y.and L.B.thank ONR(Grants nos.N00014-12-1-1034 and N00014-17-1-2818)C.P.acknowledges ARO Grant no.W911NF-16-1-0227+3 种基金We also acknowledge funding from the Luxembourg National Research Fund through the inter-mobility(Grant INTER/MOBILITY/15/9890527"GREENOX"L.B.,H.J.Z.and J.Í.)CORE(Grant C15/MS/10458889"NEWALLS",H.J.Z.and J.Í.)programs.Y.Y.thanks H.J.Xiang for useful discussion,and also acknowledge the state key program for basic research of China(Contract no.2015CB921203)National Natural Science Foundation of China(Grant no.11874207).
文摘Charged ferroelectric domain walls are fascinating electrical topological defects that can exhibit unusual properties.Here,in the search for novel phenomena,we perform and analyze first-principles calculations to investigate the effect of domain width on properties of domains with charged walls in the photovoltaic material consisting of methylammonium lead iodide hybrid perovskite.We report that such domains are stable and have rather low domain wall energy for any investigated width(that is,up to 13 lattice constants).Increasing the domain width first linearly decreases the electronic band gap from≃1.4 eV to about zero(which therefore provides an efficient band-gap engineering),before the system undergoes an insulator-to-metal transition and then remains metallic(with both the tail-to-tail and head-to-head domain walls being conductive)for the largest widths.All these results can be understood in terms of:(i)components of polarization along the normal of the domain walls being small in magnitude;(ii)an internal electric field that is basically independent of the domain width;and(iii)rather negligible charge transfer between walls.These findings deepen the knowledge of charged ferroelectric domain walls and can further broaden their potential for applications,particularly in the context of halide perovskites for photovoltaics.
文摘The effects of temperature on the convecsion of Li2 CO3 Co LiOH in a Ca（OH）2 suspension were investigated. Li2CO3 microplates were used as the Li source. The results showed that Li2CO3 was converted to LiOH via in situ ion-exchange and dissolution-precipitation routes. The formation of mixed CaxLiz-2xCO3 inter- mediate species confirmed that at 25℃ need/e-like CaCO3 was formed heterogeneously on the Li2CO3 surface via in situ ion-exchange. At 60-100℃, isolated CaCO3 agglomerates were formed homogeneously via dissolution-precipitation. Temperature increases accelerated the dissolution and conversion of Li2 CO3 to LiOH, producing solutions with high [CO32-1][Ca^2＋] ratios; this favored homogeneous precipitation of isolated CaCO3 agglomerates,
基金This work is supported by ONR Grants No.N00014-12-1-1034 and N00014-17-1-2818.L.B.also thanks the DARPA Grant No.HR0011727183‐D18AP00010Y.Y.is thankful for the discussion with Dr.Bin Xu.S.P.appreciates support of RMES 3.1649.2017/4.6 and RFBR 18-52-00029 Bel_a.
文摘In 1861,Maxwell conceived the idea of the displacement current,which then made laws of electrodynamics more complete and also resulted in the realization of devices exploiting such displacement current.Interestingly,it is presently unknown if such displacement current can result in large intrinsic ac current in ferroic systems possessing domains,despite the flurry of recent activities that have been devoted to domains and their corresponding conductivity in these compounds.Here,we report firstprinciples-based atomistic simulations that predict that the transverse(polarization-related)displacement currents of 71°and 109°domains in the prototypical BiFeO_(3) multiferroic material are significant at the walls of such domains and in the GHz regime,and,in fact,result in currents that are at least of the same order of magnitude than previously reported dc currents(that are likely extrinsic in nature and due to electrons).Such large,localized and intrinsic ac currents are found to originate from low-frequency vibrations at the domain walls,and may open the door to the design of novel devices functioning in the GHz or THz range and in which currents would be confined within the domain wall.
