Inspired by the successful synthesis of h Hv-graphane[Nano Lett.15903(2015)],a new two-dimensional(2D)Janus material Cu-graphane is proposed based on the first-principles calculations.Without the spin-orbit coupling(S...Inspired by the successful synthesis of h Hv-graphane[Nano Lett.15903(2015)],a new two-dimensional(2D)Janus material Cu-graphane is proposed based on the first-principles calculations.Without the spin-orbit coupling(SOC)effect,Cu-graphane is a Dirac semimetal with a highly anisotropic Dirac cone,whose Fermi velocity ranges from 0.12×10^(5)m/s to2.9×10^(5)m/s.The Dirac cone near the Fermi level can be well described with an extended 2D Dirac model Hamiltonian.In the presence of the SOC effect,band splitting is observed around the Fermi level,and a large intrinsic spin Hall conductivity(ISHC)with a maximum value of 346(h/e)S/cm is predicted.Moreover,the spin Hall transport can be regulated by slightly adjusting the Fermi energy,e.g.,grid voltage or chemical doping.Our work not only proposes a new 2D Janus material with a highly anisotropic Dirac cone and a large ISHC,but also reveals that a large ISHC may exist in some Dirac systems.展开更多
Objective:We aimed to establish a scoring system to predict the risk of breast cancer-related lymphedema.Methods:From April 2017 to December 2018,533 patients who previously underwent surgery for breast cancer were en...Objective:We aimed to establish a scoring system to predict the risk of breast cancer-related lymphedema.Methods:From April 2017 to December 2018,533 patients who previously underwent surgery for breast cancer were enrolled in this cross-sectional study.Univariate analysis was performed to explore and define the risk factors.A scoring system was then established on the basis of odds ratio values in the regression analysis.Results:The additive scoring system values ranged from 6 to 22.The receiver operating characteristic(ROC)curve of this scoring system showed a sensitivity and specificity of 83.3%and 57.3%,respectively,to predict the risk of lymphedema at a cut-off of 15.5 points;the area under the curve was 0.736(95%confidence interval:0.662-0.811),with x2=5.134(P=0274)for the Hosmer-Lemeshow test.Conclusions:The predictive efficiency and accuracy of the scoring system were acceptable,and the system could be used to predict and screen groups at high risk for breast cancer-related lymphedema.展开更多
Spectral emissivity is an essential and sensitive parameter to characterize the radiative capacity of the solid surface in scientific and engineering applications,which would be non-negligibly affected by surface morp...Spectral emissivity is an essential and sensitive parameter to characterize the radiative capacity of the solid surface in scientific and engineering applications,which would be non-negligibly affected by surface morphology.However,there is a lack of assessment of the effect of roughness on emissivity and a straightforward method for estimating the emissivity of rough surfaces.This paper established an estimating method based on constructing random rough surfaces to predict rough surface(Geometric region)emissivity for metal solids.Based on this method,the emissivity of ideal gray and non-gray body surfaces was calculated and analyzed.The calculated and measured spectral emissivities of GH3044,K465,DD6,and TC4 alloys with different roughness were compared.The results show that the emissivity increases with the roughness degree,and the enhancement effect weakens with the increase of roughness or emissivity due to the existing limit(emissivityε=1.0).At the same time,the roughness would not change the overall spectral distribution characteristics but may attenuate the local features of the spectral emissivity.The estimated results are in good agreement with the experimental data for the above alloys'rough surfaces.This study provides a new reliable approach to obtaining the spectral emissivity of rough surfaces.This approach is especially beneficial for measuring objects in extreme environments where emissivity is difficult to obtain.Meanwhile,this study promotes an understanding of surface morphology's effect mechanism on emissivity.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12074150,12174157,12174158,and 11874314)the Innovation and Entrepreneurship Talent Project of Jiangsu Province of China+1 种基金the Scientific Research Startup of Jiangsu University(Grant No.5501710001)the College Students’Innovation Training Program of Jiangsu Province of China(Grant No.202110299123Y)。
文摘Inspired by the successful synthesis of h Hv-graphane[Nano Lett.15903(2015)],a new two-dimensional(2D)Janus material Cu-graphane is proposed based on the first-principles calculations.Without the spin-orbit coupling(SOC)effect,Cu-graphane is a Dirac semimetal with a highly anisotropic Dirac cone,whose Fermi velocity ranges from 0.12×10^(5)m/s to2.9×10^(5)m/s.The Dirac cone near the Fermi level can be well described with an extended 2D Dirac model Hamiltonian.In the presence of the SOC effect,band splitting is observed around the Fermi level,and a large intrinsic spin Hall conductivity(ISHC)with a maximum value of 346(h/e)S/cm is predicted.Moreover,the spin Hall transport can be regulated by slightly adjusting the Fermi energy,e.g.,grid voltage or chemical doping.Our work not only proposes a new 2D Janus material with a highly anisotropic Dirac cone and a large ISHC,but also reveals that a large ISHC may exist in some Dirac systems.
基金This study was supported by Nursing Research Grant of Peking University Health Science Center(BMU20160517).
文摘Objective:We aimed to establish a scoring system to predict the risk of breast cancer-related lymphedema.Methods:From April 2017 to December 2018,533 patients who previously underwent surgery for breast cancer were enrolled in this cross-sectional study.Univariate analysis was performed to explore and define the risk factors.A scoring system was then established on the basis of odds ratio values in the regression analysis.Results:The additive scoring system values ranged from 6 to 22.The receiver operating characteristic(ROC)curve of this scoring system showed a sensitivity and specificity of 83.3%and 57.3%,respectively,to predict the risk of lymphedema at a cut-off of 15.5 points;the area under the curve was 0.736(95%confidence interval:0.662-0.811),with x2=5.134(P=0274)for the Hosmer-Lemeshow test.Conclusions:The predictive efficiency and accuracy of the scoring system were acceptable,and the system could be used to predict and screen groups at high risk for breast cancer-related lymphedema.
基金funded by the Department of Science and Technology of Sichuan Province(Nos.2021JDTD0030,2022JDJQ0033,and 2022012)the National Natural Science Foundation of China(Nos.U20A20213 and 62275059)+2 种基金the National Science and Technology Major Project(J2019-V-0006-0100)Young Elite Scientists Sponsorship Program by CAST(No.2019QNRC001)the Chengdu Science and Technology Project(No.2020-GH02-0065-HZ).
文摘Spectral emissivity is an essential and sensitive parameter to characterize the radiative capacity of the solid surface in scientific and engineering applications,which would be non-negligibly affected by surface morphology.However,there is a lack of assessment of the effect of roughness on emissivity and a straightforward method for estimating the emissivity of rough surfaces.This paper established an estimating method based on constructing random rough surfaces to predict rough surface(Geometric region)emissivity for metal solids.Based on this method,the emissivity of ideal gray and non-gray body surfaces was calculated and analyzed.The calculated and measured spectral emissivities of GH3044,K465,DD6,and TC4 alloys with different roughness were compared.The results show that the emissivity increases with the roughness degree,and the enhancement effect weakens with the increase of roughness or emissivity due to the existing limit(emissivityε=1.0).At the same time,the roughness would not change the overall spectral distribution characteristics but may attenuate the local features of the spectral emissivity.The estimated results are in good agreement with the experimental data for the above alloys'rough surfaces.This study provides a new reliable approach to obtaining the spectral emissivity of rough surfaces.This approach is especially beneficial for measuring objects in extreme environments where emissivity is difficult to obtain.Meanwhile,this study promotes an understanding of surface morphology's effect mechanism on emissivity.
