Long‐term variations of South Atlantic anomaly (SAA) are generally derived by fitting a Gaussian‐like function to an averaged distribution of the proton flux at a certain altitude accumulated over time periods for a month or longer. These data do not show the short‐term variation of SAA arising from geomagnetic storm effects whose time scale is less than a month. To investigate the short‐term variations, the features of SAA for the high‐energy protons detected by NOAA Polar Orbiting Environmental Satellites during 1998–2008 have been investigated with a 5 day running average method. It is found that the two SAA parameters for three proton channels reflect the maximal proton flux in SAA and the extension of SAA decreases several percent during geomagnetic storms. Possible reasons for the decreases of the two SAA parameters for high‐energy protons are discussed. Proton losses at the outer boundary of the inner radiation belt can be explained by the field line curvature scattering mechanism, while the decrease of the proton flux near the center of SAA is probably caused by the enhanced neutral atmospheric density during geomagnetic storms. The study of the behavior of high‐energy protons in SAA is useful for understanding of storm time and long‐term variations of the radiation environment near Earth and for constructing dynamic radiation belt models.

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Previous studies from European and East Asian cohorts reported conflicting results over whether and how the frequencies of the three common alleles, ε2, ε3 and ε4, of the apolioprotein E gene (APOE), in long-lived individuals differ from those in younger age groups. This study was the first to analyse these frequencies of long-lived individuals from central China. Genotyping of APOE alleles and genotypes was carried out in 70 long-lived individuals and 204 younger controls. No difference in the frequency of any APOE allele or genotype was found between the long-lived participants and their younger controls, but the long-lived group seemed to have a higher ε4 frequency (15.71%) than the 24–50 and 51–75 age groups (10.2% and 11.32%, P > 0.05). Notably, when compared with two other Chinese studies, the central China long-lived group had a higher ε4 frequency than its southern and eastern China counterparts (15.71% vs. 2.82% and 2.54%, P < 0.05). It is not clear to what extent population substructure or lifestyles contributed to these divergent findings. A clear understanding of the contribution of APOE polymorphisms to longevity in the Han Chinese population may be achieved only through large scale studies with participants from well-defined regional clusters.