Magnetite nanoparticles show promising applications in drug delivery,catalysis,and spintronics.The surface of magnetite plays an important role in these applications.Therefore,it is critical to understand the surface ...Magnetite nanoparticles show promising applications in drug delivery,catalysis,and spintronics.The surface of magnetite plays an important role in these applications.Therefore,it is critical to understand the surface structure of Fe_(3)O_(4)at atomic scale.Here,using a combination of first-principles calculations,particle swarm optimization(PSO)method and machine learning,we investigate the possible reconstruction and stability of Fe_(3)O_(4)(001)surface.The results show that besides the subsurface cation vacancy(SCV)reconstruction,an A layer with Fe vacancy(A-layer-V_(Fe))reconstruction of the(001)surface also shows very low surface energy especially at oxygen poor condition.Molecular dynamics simulation based on the iron–oxygen interaction potential function fitted by machine learning further confirms the thermodynamic stability of the A-layer-V_(Fe)reconstruction.Our results are also instructive for the study of surface reconstruction of other metal oxides.展开更多
Influenza-associated encephalopathy (IAE) can perform as varying patterns of neuroimaging. Central brain herniation (CBH) secondary to IAE is rare;it may be a bad prognosis. Here, we presented a 4-year-old girl with i...Influenza-associated encephalopathy (IAE) can perform as varying patterns of neuroimaging. Central brain herniation (CBH) secondary to IAE is rare;it may be a bad prognosis. Here, we presented a 4-year-old girl with influenza who had a pontocerebellar hypoplasia (PCH) history;she performed the second Magnetic Resonance Imaging (MRI) on Day 6 from onset, showed the diffuse edema and the occurrence of central herniation;the medulla was “Z-like” folded and the basal cisterns were obliterated completely. Finally she was declared dead. The imbalance between supratentorial and infratentorial pressure can lead to the occurrence of CBH. Severe edema relates to IAE and unstable structure of the posterior fossa might be the main reason for the herniation. MRI is helpful in early diagnosis. Early treatment of cerebral edema in patients with congenital abnormalities of the posterior fossa is vital for their management.展开更多
基金the National Natural Science Foundation of China(Grant Nos.12004064,12074053,and 91961204)the Fundamental Research Funds for the Central Universities(Grant No.DUT22LK11)XingLiaoYingCai Project of Liaoning Province,China(Grant No.XLYC1907163)。
文摘Magnetite nanoparticles show promising applications in drug delivery,catalysis,and spintronics.The surface of magnetite plays an important role in these applications.Therefore,it is critical to understand the surface structure of Fe_(3)O_(4)at atomic scale.Here,using a combination of first-principles calculations,particle swarm optimization(PSO)method and machine learning,we investigate the possible reconstruction and stability of Fe_(3)O_(4)(001)surface.The results show that besides the subsurface cation vacancy(SCV)reconstruction,an A layer with Fe vacancy(A-layer-V_(Fe))reconstruction of the(001)surface also shows very low surface energy especially at oxygen poor condition.Molecular dynamics simulation based on the iron–oxygen interaction potential function fitted by machine learning further confirms the thermodynamic stability of the A-layer-V_(Fe)reconstruction.Our results are also instructive for the study of surface reconstruction of other metal oxides.
文摘Influenza-associated encephalopathy (IAE) can perform as varying patterns of neuroimaging. Central brain herniation (CBH) secondary to IAE is rare;it may be a bad prognosis. Here, we presented a 4-year-old girl with influenza who had a pontocerebellar hypoplasia (PCH) history;she performed the second Magnetic Resonance Imaging (MRI) on Day 6 from onset, showed the diffuse edema and the occurrence of central herniation;the medulla was “Z-like” folded and the basal cisterns were obliterated completely. Finally she was declared dead. The imbalance between supratentorial and infratentorial pressure can lead to the occurrence of CBH. Severe edema relates to IAE and unstable structure of the posterior fossa might be the main reason for the herniation. MRI is helpful in early diagnosis. Early treatment of cerebral edema in patients with congenital abnormalities of the posterior fossa is vital for their management.
