Objective:To discusses the variations of 7Be, 137Cs and 210Pb activity concentrations in the air in Beijing from March 16, 2021 to March 31, 2023, and their correlation with temperature, precipitation, relative humidity, barometric pressure, PM10 (only limited to 137Cs) and other meteorological parameters. Methods:A total of 60 aerosol samples were collected using the HRHA01-SFS1000/A ultra-large flowair sampler in the automatic radiation monitoring station. The activity concentrations of 7Be, 137Cs and 210Pb in the aerosol samples were measured by GMX-60 low background anti-Compton high purity germanium gamma spectrometer. Pearson correlation coefficient was used to show the correlation of the relevant parameters. Results:The seasonal mean values of 7Be activity concentration were spring 4.31 mBq/m 3, summer 3.53 mBq/m 3, autumn 3.09 mBq/m 3 and winter 2.45 mBq/m 3, respectively, ranging from 1.17 to 7.79 mBq/m 3, with the overall mean of (3.36±1.33) mBq/m 3. The activity concentration of 137Cs ranged from 0.39 to 8.49 μBq/m 3, with an average of (0.59±1.47) μBq/m 3. The average activity concentrations of 210Pb were spring 0.53 mBq/m 3, summer 0.44 mBq/m 3, autumn 0.72 mBq/m 3 and winter 0.75 mBq/m 3, respectively, ranging from 0.21 to 1.36 mBq/m 3, with an average of (0.56±0.26) mBq/m 3. The activity concentration of 7Be was correlated with temperature and pressure ( r=0.38, -0.40), the activity concentration of 137Cs was correlated with precipitation ( r=-0.41), and the activity concentration of 210Pb was correlated with temperature and pressure ( r=-0.31, 0.37). The variation of 137Cs activity concentration in the air showed an obvious seasonal pattern, and the peak value generally appears in spring of each year (March to May), which was related to the frequent spring dust in Beijing. The activity concentration of 210Pb in the air was affected by coal combustion heating in winter, and has a peak value during November to March. Conclusions:The activity concentrations of 7Be, 137Cs and 210Pb in the air in Beijing are within the normal range, showing a seasonal trend.

A recombinant enzyme-mediated nucleic acid amplification(RAA)technology combined with colloidal gold test strips was developed for the rapid detection of bovine enterovirus(BEV).Using the highly conserved BEV 5'UTR as the target sequence,the primers were designed and screened.Downstream primer labeled with biotin at the 5'end and the probe labeled with 6-FAM at the 5'end were used to establish the RT-RAA method.The test strips were assembled by using mouse-derived anti-6-FAM monoclonal antibody as the gold standard antibody,with a streptavidin encapsulated in the detection line and sheep anti-mouse IgG encapsulated in the quality control line.A RT-RAA-LFD method was established by combing RAA technique with the prepared later-al flow device test strips for the detection of bovine enterovirus nucleic acids.The specificity,sensi-tivity,repeatability,and clinical application of the method are also evaluated.The results showed that the optimal primer concentration of this method was 5 μmol/L,and the amplification of BEV nucleic acids was accomplished by reacting at 35 ℃ for 8 min with the lowest detection limit of 101 copies/μL.No cross-reactivity with bovine viral diarrhea virus,bovine parvovirus,and foot-and-mouth disease virus was observed.The efficacy for the prepared test strips was at least for 90 d kept at 4 ℃.Detection of 74 clinical samples yielded a similar result compared with RT-PCR method.The above results demonstrated that the BEV RT-RAA-LFD method established in this study has high sensitivity,specificity,and more convenient to use,which is suitable for clinical de-tection on-site and provides a new technical tool for the diagnosis and epidemiological investigation of BEV infection.

Circular RNA(circRNA)represents a unique class of closed-loop structured non-coding RNAs involved in various biological processes such as cell proliferation,differentiation,and apopto-sis.They play a significant role in the development of numerous diseases,and also serve as poten-tial biomarkers and therapeutic targets.To explore the impact of circRNA on viral replication,this study performed an omics measurement and analysis of circRNA differential expression in MC38 cells infected with HY12 enterovirus.It was found that,following HY12 virus infection,the ex-pressionlevels of 570 circRNAs were upregulated,while 381 circRNAs were downregulated.A-mong the upregulated circRNAs,the significantly upregulated circRNA mmu_circ_0001083 was selected for further investigation into its association with HY12 infection and its impact on viral replication.The results indicated that after HY12 virus infection,the expression of host circRNA mmu_circ_0001083 significantly increased,and its expression level was dependent on the virus dos-age and time.Compared to normal MC38 cells infected with the HY12 virus,cells with knocked down expression of circRNA mmu_circ_0001083 showed reduced expression of the 2C protein and significantly lower viral titers.Conversely,after HY12 virus infection in MC38 cells with overexpressed circRNA mmu_circ_0001083,there was an increase in the expression of the 2C pro-tein and a significant rise in viral titers.These results suggest that the upregulation of host cir-cRNA mmu_circ_0001083 is significantly positively correlated with the replication of HY12 virus,meaning mmu_circ_0001083 plays a positive regulatory role in the replication of HY12.This find-ing lays a foundation for future in-depth studies on the regulatory mechanisms of circRNA on viral replication.