Stacking-dependent magnetism in van der Waals materials has caught intense interests.Based on the first principle calculations,we investigate the coupling between stacking orders and interlayer magnetic orders in bila...Stacking-dependent magnetism in van der Waals materials has caught intense interests.Based on the first principle calculations,we investigate the coupling between stacking orders and interlayer magnetic orders in bilayer H-VSe 2.It is found that there are two stable stacking orders in bilayer H-VSe 2,named AB-stacking and A′B-stacking.Under standard DFT framework,the A′B-stacking prefers the interlayer AFM order and is semiconductive,whereas the AB-stacking prefers the FM order and is metallic.However,under the DFT+U framework both the stacking orders prefer the interlayer AFM order and are semiconductive.By detailedly analyzing this difference,we find that the interlayer magnetism originates from the competition between antiferromagnetic interlayer super-superexchange and ferromagnetic interlayer double exchange,in which both the interlayer Se-4 p z orbitals play a crucial role.In the DFT+U calculations,the double exchange is suppressed due to the opened bandgap,such that the interlayer magnetic orders are decoupled with the stacking orders.Based on this competition mechanism,we propose that a moderate hole doping can significantly enhance the interlayer double exchange,and can be used to switch the interlayer magnetic orders in bilayer VSe 2.This method is also applicable to a wide range of semiconductive van der Waals magnets.展开更多
Background:Prospective evidence on how offspring number influences morbidity and mortality remains limited.This study investigated the associations between number of offspring and morbidity and mortality risks among 0...Background:Prospective evidence on how offspring number influences morbidity and mortality remains limited.This study investigated the associations between number of offspring and morbidity and mortality risks among 0.5 million Chinese adults.Methods:By using data from the China Kadoorie Biobank(CKB;n=512,723,an approximately 12-year follow-up),sex-stratified phenome-wide association study(PheWAS)analyses were conducted to investigate associations between offspring number(without vs.with offspring;more than one vs.one offspring)and risks of ICD10-coded morbidity and mortality.Sex-specific adjusted hazard ratios(aHRs)and 95%confidence intervals(CIs)were estimated by Cox proportional-hazards models.Results:Among 210,129 men and 302,284 women aged 30-79 years,1,338,837 incident events were recorded.PheWAS results revealed that offspring number was associated with disease risks across multiple systems.Cox models showed that childless men(vs.one offspring)had higher risks for nine of 36 diseases,while childless women for five of 37.Each additional offspring was associated with reduced risks of mental and behavioral disorders in men(aHR[95%CI]=0.93[0.87-0.98])and both mental and behavioral disorders(aHR[95%CI]=0.93[0.89-0.97])and breast cancer(aHR[95%CI]=0.82[0.78-0.86])in women.However,each additional offspring was associated with a 4%increase in the risk of cholelithiasis and cholecystitis in women(aHR[95%CI]=1.04[1.02-1.07]).Among 282,630 patients,44,533 deaths were documented.Childless patients had higher mortality risk in both men(aHR[95%CI]=1.37[1.28-1.47])and women(aHR[95%CI]=1.27[1.15-1.41]).For men,each additional offspring reduced mortality by 4%(aHR[95%CI]=0.96[0.95-0.98]),while for women,the lowest risk was observed among those with three to four offspring(P_(nonlinear)<0.0001).Conclusions:Offspring number is closely linked to morbidity and mortality risks.Further research is warranted to verify our findings and clarify the underlying mechanisms involved.展开更多
Altermagnetic materials have recently attracted significant attention due to their unique intrinsic crystal symmetry.Breaking the lattice symmetry can yield a non-negligible piezomagnetic effect,which refers to a line...Altermagnetic materials have recently attracted significant attention due to their unique intrinsic crystal symmetry.Breaking the lattice symmetry can yield a non-negligible piezomagnetic effect,which refers to a linear relationship between strain and magnetization.We proposed a method based onε_(xz)andε_(xy)shear strains that induced additional spin splitting along band paths that were originally spin-degenerate and generated weak ferromagnetic moments in altermagnetic CoF_(2)and RuO_(2).Additionally,the signs of spin splitting and weak ferromagnetic moments were switched by reversing the shear strain direction.The weak ferromagnetism had a substantial contribution from the orbital magnetic moments,with its y(z)component associated with the charge quadrupole moment.Our study highlights that shear strain provides a novel approach for exploring the physical properties of spin splitting,piezomagnetism,and multipolar order,while also broadening avenues for tuning the properties of altermagnetic materials.展开更多
Two-dimensional materials with high-temperature ferromagnetism and half-metallicity have the latest applications in spintronic devices.Based on first-principles calculations,we have investigated a novel two-dimensiona...Two-dimensional materials with high-temperature ferromagnetism and half-metallicity have the latest applications in spintronic devices.Based on first-principles calculations,we have investigated a novel two-dimensional CrS_(2) phase with an orthorhombic lattice.Our results suggest that it is stable in dynamics,thermodynamics,and mechanics.The ground state of monolayer orthorhombic CrS_(2) is both ferromagnetic and half-metallic,with a high Curie temperature of 895 K and a large spin-flipping gap on values of 0.804 eV.This room-temperature ferromagnetism and halfmetallicity can maintain stability against a strong biaxial strain ranging from–5%to 5%.Meanwhile,increasing strain can significantly maintain the out-of-plane magnetic anisotropy.A density of states analysis,together with the orbital-resolved magnetic anisotropy energy,has revealed that the strain-enhanced MAE is highly related to the 3d-orbital splitting of Cr atoms.Our results suggest the monolayer orthorhombic CrS_(2) is an ideal candidate for future spintronics.展开更多
Developing an effective catalyst for the selective oxidation of hydrocarbon to high value-added compounds remains as a challenge in terms of the growing global concerns about green chemistry and environmental sustaina...Developing an effective catalyst for the selective oxidation of hydrocarbon to high value-added compounds remains as a challenge in terms of the growing global concerns about green chemistry and environmental sustainability.Herein,asymmetric nitrogen and phosphorus co-coordinated Ce single-atom sites(Ce-N_(3)P-C)were constructed for the activation of aromatic C-H bond.Ce-N_(3)P-C demonstrates excellent catalytic performance for efficient solvent-free aerobic oxidation of aromatic C-H bonds,especially for oxidation of ethylbenzene with 97%selectivity of acetophenone and high stability.The turnover frequency(TOF)value is 536 h-1,which is the highest level among reported non-precious-metal catalysts in a similar system.The partial substitution of coordinated N with P atom breaks the symmetry of the active moiety of Ce and raises the electron density of Ce center.The reduced valence state of metallic Ce indicates that more electrons could transfer to the antibonding π-orbital of the adsorbed O_(2),thus promoting the subsequent free radical reaction and accelerating the rate-determining step.The breaking of coordination symmetry of single-atom site catalyst by introducing heteroatoms to tune its active moiety paves a way to boost the catalytic performance of similar catalysts.展开更多
Summary What is already known about this topic?The majority of Chinese patients with diabetes failed to achieve the level of physical activity recommended by clinical guidelines.What is added by this report?The preval...Summary What is already known about this topic?The majority of Chinese patients with diabetes failed to achieve the level of physical activity recommended by clinical guidelines.What is added by this report?The prevalence of low-level physical activity was found to be greater in individuals diagnosed with diabetes.It was observed that patients with a protracted duration of diabetes demonstrated a propensity to participate in lower levels of physical activity compared to those with a shorter disease trajectory.The likelihood of engaging in low-level physical activity associated with diabetes was higher in rural inhabitants,those with medium-tier education,employed individuals,and individuals who had longer sleep durations.What are the implications for public health practice?Developing strategies and interventions to encourage greater involvement of Chinese diabetic patients in physical activity is essential.However,these strategies must take population characteristics into account.展开更多
基金Supported by the National Natural Science Foundation of China(Grant No.51272291)the Distinguished Young Scholar Foundation of Hunan Province(Grant No.2015JJ1020)+3 种基金the Young Scholar Foundation of Hunan Province(Grant No.2016JJ3142)the Central South University Research Fund for Sheng-Hua ScholarsCentral South University State Key Laboratory of Powder Metallurgythe Fundamental Research Funds for the Central Universities of Central South University
文摘Stacking-dependent magnetism in van der Waals materials has caught intense interests.Based on the first principle calculations,we investigate the coupling between stacking orders and interlayer magnetic orders in bilayer H-VSe 2.It is found that there are two stable stacking orders in bilayer H-VSe 2,named AB-stacking and A′B-stacking.Under standard DFT framework,the A′B-stacking prefers the interlayer AFM order and is semiconductive,whereas the AB-stacking prefers the FM order and is metallic.However,under the DFT+U framework both the stacking orders prefer the interlayer AFM order and are semiconductive.By detailedly analyzing this difference,we find that the interlayer magnetism originates from the competition between antiferromagnetic interlayer super-superexchange and ferromagnetic interlayer double exchange,in which both the interlayer Se-4 p z orbitals play a crucial role.In the DFT+U calculations,the double exchange is suppressed due to the opened bandgap,such that the interlayer magnetic orders are decoupled with the stacking orders.Based on this competition mechanism,we propose that a moderate hole doping can significantly enhance the interlayer double exchange,and can be used to switch the interlayer magnetic orders in bilayer VSe 2.This method is also applicable to a wide range of semiconductive van der Waals magnets.
基金supported by grants from the National Key R&D Program of China(Nos.2023YFC2509400 and 2020YFC2003405)the National Natural Science Foundation of China(Nos.82103920 and 82388102)+4 种基金supported by a grant from the Kadoorie Charitable Foundation in Hong Kongsupported by grants from the UK Wellcome Trust(Nos.212946/Z/18/Z,202922/Z/16/Z,104085/Z/14/Z,and 088158/Z/09/Z)the National Key R&D Program of China(Nos.2016YFC0900500 and 2020YFC2003405)the National Natural Science Foundation of China(Nos.81390540,91846303 and 81941018)the Chinese Ministry of Science and Technology(No.2011BAI09B01).
文摘Background:Prospective evidence on how offspring number influences morbidity and mortality remains limited.This study investigated the associations between number of offspring and morbidity and mortality risks among 0.5 million Chinese adults.Methods:By using data from the China Kadoorie Biobank(CKB;n=512,723,an approximately 12-year follow-up),sex-stratified phenome-wide association study(PheWAS)analyses were conducted to investigate associations between offspring number(without vs.with offspring;more than one vs.one offspring)and risks of ICD10-coded morbidity and mortality.Sex-specific adjusted hazard ratios(aHRs)and 95%confidence intervals(CIs)were estimated by Cox proportional-hazards models.Results:Among 210,129 men and 302,284 women aged 30-79 years,1,338,837 incident events were recorded.PheWAS results revealed that offspring number was associated with disease risks across multiple systems.Cox models showed that childless men(vs.one offspring)had higher risks for nine of 36 diseases,while childless women for five of 37.Each additional offspring was associated with reduced risks of mental and behavioral disorders in men(aHR[95%CI]=0.93[0.87-0.98])and both mental and behavioral disorders(aHR[95%CI]=0.93[0.89-0.97])and breast cancer(aHR[95%CI]=0.82[0.78-0.86])in women.However,each additional offspring was associated with a 4%increase in the risk of cholelithiasis and cholecystitis in women(aHR[95%CI]=1.04[1.02-1.07]).Among 282,630 patients,44,533 deaths were documented.Childless patients had higher mortality risk in both men(aHR[95%CI]=1.37[1.28-1.47])and women(aHR[95%CI]=1.27[1.15-1.41]).For men,each additional offspring reduced mortality by 4%(aHR[95%CI]=0.96[0.95-0.98]),while for women,the lowest risk was observed among those with three to four offspring(P_(nonlinear)<0.0001).Conclusions:Offspring number is closely linked to morbidity and mortality risks.Further research is warranted to verify our findings and clarify the underlying mechanisms involved.
基金supported by the Key Project of the Natural Science Program of Xinjiang Uygur Autonomous Region(Grant No.2023D01D03)the National Natural Science Foundation of China(Grant Nos.52073308,T2495212,and 12004439)+2 种基金the Tianchi-Talent Project for Young Doctors of Xinjiang Uygur Autonomous Region(Grant No.51052300570)the Outstanding Doctoral Student Innovation Project of Xinjiang University(Grant No.XJU2023BS028)carried out in part using computing resources at the High-Performance Computing Center of Central South University.
文摘Altermagnetic materials have recently attracted significant attention due to their unique intrinsic crystal symmetry.Breaking the lattice symmetry can yield a non-negligible piezomagnetic effect,which refers to a linear relationship between strain and magnetization.We proposed a method based onε_(xz)andε_(xy)shear strains that induced additional spin splitting along band paths that were originally spin-degenerate and generated weak ferromagnetic moments in altermagnetic CoF_(2)and RuO_(2).Additionally,the signs of spin splitting and weak ferromagnetic moments were switched by reversing the shear strain direction.The weak ferromagnetism had a substantial contribution from the orbital magnetic moments,with its y(z)component associated with the charge quadrupole moment.Our study highlights that shear strain provides a novel approach for exploring the physical properties of spin splitting,piezomagnetism,and multipolar order,while also broadening avenues for tuning the properties of altermagnetic materials.
基金This work was financially supported by the Key Project of the Natural Science Program of Xinjiang Uygur Autonomous Region(Grant No.2013D01D03)the National Natural Science Foundation of China(Grant Nos.52073308 and 12004439)+5 种基金the Central South University Research Fund for Sheng Hua Scholars(Grant No.502033019)Hunan Provincial Innovation Foundation for Postgraduate(Grant No.CX20190107)the State Key Laboratory of Powder Metallurgy at Central South University,the Fundamental Research Funds for the Central Universities of Central South University,the Tianchi-Talent Project for Young Doctors of Xinjiang Uygur Autonomous Region(No.51052300570)the National Science Foundation of Hunan Province(No.2021JJ30864)the Key Project of the Natural Science Program of Xinjiang Uygur Autonomous Region(Grant No.2023D01D03)the Outstanding Doctoral Student Innovation Project of Xinjiang University(No.XJU2023BS028).
文摘Two-dimensional materials with high-temperature ferromagnetism and half-metallicity have the latest applications in spintronic devices.Based on first-principles calculations,we have investigated a novel two-dimensional CrS_(2) phase with an orthorhombic lattice.Our results suggest that it is stable in dynamics,thermodynamics,and mechanics.The ground state of monolayer orthorhombic CrS_(2) is both ferromagnetic and half-metallic,with a high Curie temperature of 895 K and a large spin-flipping gap on values of 0.804 eV.This room-temperature ferromagnetism and halfmetallicity can maintain stability against a strong biaxial strain ranging from–5%to 5%.Meanwhile,increasing strain can significantly maintain the out-of-plane magnetic anisotropy.A density of states analysis,together with the orbital-resolved magnetic anisotropy energy,has revealed that the strain-enhanced MAE is highly related to the 3d-orbital splitting of Cr atoms.Our results suggest the monolayer orthorhombic CrS_(2) is an ideal candidate for future spintronics.
基金supported by the National Natural Science Foundation of China(No.22301158)the Science and Technology Project of Henan Province(No.252102231076).
文摘Developing an effective catalyst for the selective oxidation of hydrocarbon to high value-added compounds remains as a challenge in terms of the growing global concerns about green chemistry and environmental sustainability.Herein,asymmetric nitrogen and phosphorus co-coordinated Ce single-atom sites(Ce-N_(3)P-C)were constructed for the activation of aromatic C-H bond.Ce-N_(3)P-C demonstrates excellent catalytic performance for efficient solvent-free aerobic oxidation of aromatic C-H bonds,especially for oxidation of ethylbenzene with 97%selectivity of acetophenone and high stability.The turnover frequency(TOF)value is 536 h-1,which is the highest level among reported non-precious-metal catalysts in a similar system.The partial substitution of coordinated N with P atom breaks the symmetry of the active moiety of Ce and raises the electron density of Ce center.The reduced valence state of metallic Ce indicates that more electrons could transfer to the antibonding π-orbital of the adsorbed O_(2),thus promoting the subsequent free radical reaction and accelerating the rate-determining step.The breaking of coordination symmetry of single-atom site catalyst by introducing heteroatoms to tune its active moiety paves a way to boost the catalytic performance of similar catalysts.
基金Supported by National Natural Science Foundation of China(82192904,82192901,82192900)“Precision Medicine Research”Key Project,National Key Research and Development Program of China(2016YFC0900500)Kadoorie Charitable Foundation in Hong Kong of China.
文摘Summary What is already known about this topic?The majority of Chinese patients with diabetes failed to achieve the level of physical activity recommended by clinical guidelines.What is added by this report?The prevalence of low-level physical activity was found to be greater in individuals diagnosed with diabetes.It was observed that patients with a protracted duration of diabetes demonstrated a propensity to participate in lower levels of physical activity compared to those with a shorter disease trajectory.The likelihood of engaging in low-level physical activity associated with diabetes was higher in rural inhabitants,those with medium-tier education,employed individuals,and individuals who had longer sleep durations.What are the implications for public health practice?Developing strategies and interventions to encourage greater involvement of Chinese diabetic patients in physical activity is essential.However,these strategies must take population characteristics into account.
