Summary What is already known about this topic?Limited evidence on healthy longevity was provided in the world,and no studies investigated the fractions of healthy longevity attributed to modifiable factors.What is ad...Summary What is already known about this topic?Limited evidence on healthy longevity was provided in the world,and no studies investigated the fractions of healthy longevity attributed to modifiable factors.What is added by this report?Incidences of longevity and healthy longevity in China are provided.It reveals that the total weighted population attributable fractions for lifestyles and all modifiable factors were 32.8% and 83.7% for longevity,respectively,and 30.4% and 73.4% for healthy longevity,respectively.What are the implications for public health practice?China has a high potential for longevity and healthy longevity.Strategies may be targeted at education and residence in early life as well as healthy lifestyles,disease prevention,and functional optimization in late life.展开更多
The lead-free 0.96NaNbO_(3)-0.04CaSnO_(3) ceramics with rare-earth dopants(La,Sm and Lu)(NCLn100x)were prepared and characterized.It is found that a certain amount of La substitution stabilizes the antiferroelectric(A...The lead-free 0.96NaNbO_(3)-0.04CaSnO_(3) ceramics with rare-earth dopants(La,Sm and Lu)(NCLn100x)were prepared and characterized.It is found that a certain amount of La substitution stabilizes the antiferroelectric(AFE)phase but alleviates the lattice distortion in the fresh samples.Re-entrant-like characteristics are observed in the temperature e dielectric constant curves with the room temperature P phase gradually replaced by a possible R phase.Relaxor-like hysteresis loops with suppressed hysteresis loss and remanent polarization were obtained at high La content,achieving a relatively high Wre of 2.1 J/cm^(3) at a low electric field(250 kV/cm).The relaxation behaviors of the ferroelectric(FE)domain measured by piezoresponse force microscopy suggest an even long characteristic relaxation time of field-induced FE phase,which is different from the situations of other AFE perovskites.Via an explanatory defected diatomic chain model,we propose that a much larger mass of substitutive ion than the origin one helps to induce low-frequency localized mode,which is believed to be in favor of the formation of polar nano-regions and hence strengthens the dynamic stability of FE phase during electric field loading.Our research provides a further understanding of the tuning strategy for enhancing the antiferroelectricity of the NaNbO_(3)-based system.展开更多
基金Supported by the National Natural Science Foundation of China(grant numbers 82025030 and 81941023)Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences(grant number 2021-JKCS-028)Claude D.Pepper Older Americans Independence Centers grant(grant number 5P30 AG028716 from NIA).
文摘Summary What is already known about this topic?Limited evidence on healthy longevity was provided in the world,and no studies investigated the fractions of healthy longevity attributed to modifiable factors.What is added by this report?Incidences of longevity and healthy longevity in China are provided.It reveals that the total weighted population attributable fractions for lifestyles and all modifiable factors were 32.8% and 83.7% for longevity,respectively,and 30.4% and 73.4% for healthy longevity,respectively.What are the implications for public health practice?China has a high potential for longevity and healthy longevity.Strategies may be targeted at education and residence in early life as well as healthy lifestyles,disease prevention,and functional optimization in late life.
基金supported by the National Natural Science Foundation of China(Grant No.11774366 and No.51831010)the International Partnership Program of Chinese Academy of Sciences(Grant No.GJHZ1821).
文摘The lead-free 0.96NaNbO_(3)-0.04CaSnO_(3) ceramics with rare-earth dopants(La,Sm and Lu)(NCLn100x)were prepared and characterized.It is found that a certain amount of La substitution stabilizes the antiferroelectric(AFE)phase but alleviates the lattice distortion in the fresh samples.Re-entrant-like characteristics are observed in the temperature e dielectric constant curves with the room temperature P phase gradually replaced by a possible R phase.Relaxor-like hysteresis loops with suppressed hysteresis loss and remanent polarization were obtained at high La content,achieving a relatively high Wre of 2.1 J/cm^(3) at a low electric field(250 kV/cm).The relaxation behaviors of the ferroelectric(FE)domain measured by piezoresponse force microscopy suggest an even long characteristic relaxation time of field-induced FE phase,which is different from the situations of other AFE perovskites.Via an explanatory defected diatomic chain model,we propose that a much larger mass of substitutive ion than the origin one helps to induce low-frequency localized mode,which is believed to be in favor of the formation of polar nano-regions and hence strengthens the dynamic stability of FE phase during electric field loading.Our research provides a further understanding of the tuning strategy for enhancing the antiferroelectricity of the NaNbO_(3)-based system.
