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The uptake of radiocesium (RCs) by plants is key to the assessment of its environmental risk. However, the transfer process of RCs in the water-vegetable system still remains unclear. In this work, the uptake and accumulation processes of Cs+ (0-10 mM) in lettuce were explored under different conditions by using hydroponics. The results showed that the higher exposure concentration of Cs+ could lead to a faster uptake rate and would be beneficial to the uptake and accumulation of Cs+. The uptake of K+ by roots and leaves was inhibited significantly when Cs+ concentration increased, but unapparent for Ca2+ and Mg2+. It was found that the higher K+ and Ca2+ concentration was, the higher inhibition was found for the uptake of Cs+ in root. The uptake of Cs+ leads the decrease of chlorophyll content and brought a negative effect on plant photosynthesis, consequently, a negative effect on lettuce morphology and obvious decrease of biomass and root length. The contents of glutathione (GSH), malondialdehyde (MDA), and root vitality were increasing during the growth following stress of high concentrations of Cs+, which caused stresses on the antioxidant system of lettuce. The enrichment coefficient for Cs+ in leaves was in the range of 8-217. Moreover, the transfer factor was in the range of 0.114-0.828, which suggested that the high Cs+ concentration could enhance the transfer of Cs+ from lettuce root to leaf. This study provides more information on the transfer of RCs from water to food chain, promoting the understanding of the potential risk of RCs. [ABSTRACT FROM AUTHOR]

The tick‐borne pathogen Anaplasma phagocytophilum is an emerging infectious disease threat, but the overall A. phagocytophilum seroprevalence in humans is unclear. We performed a systematic search of English databases for literature published from 1994 to 2018. Studies reporting serological evidence of A. phagocytophilum infection in humans were included, and the information was extracted by two authors independently. As the study heterogeneity was significant, a random‐effects model was used to calculate the overall pooled seroprevalence. Data from 56 studies involving 28,927 individuals from four continents were included. The seroprevalence reported by the studies ranged from 0% to 37.26%. The overall pooled A. phagocytophilum seroprevalence in humans was 8.4% (95% CI: 6.6%–10.4%). The seroprevalence was highest in high‐risk population (13.8%) and lowest in healthy population (5.0%). The estimated A. phagocytophilum seroprevalence of febrile patient, tick‐bitten and tick‐borne diseases populations was 6.4%, 8.0% and 9.0%, respectively. This meta‐analysis demonstrated first A. phagocytophilum seroprevalence estimates in different populations (healthy, febrile patient, high‐risk, tick‐bitten and tick‐borne diseases populations); it seems likely that present surveillance efforts are missing mild or asymptomatic infections of humans. [ABSTRACT FROM AUTHOR]