Zeolitic imidazolate framework-8 as a nanoadsorbent for radon capture

The feasibility of adsorption and the adsorption behavior of radon on a nanomaterial-based zeolitic imidazolate framework-8(ZIF-8) adsorbent were investigated.Grand canonical Monte Carlo simulation and four-channel low-background a/b measurement were performed to examine the adsorption kinetics of this adsorbent. Results demonstrated that ZIF-8 is a good adsorbent of radon.Therefore, this adsorbent can be used to significantly reduce the hazardous effects of radon on occupational radiation workers.

The role of crm-1 in ionizing radiation-induced nervous system dysfunction in Caenorhabditis elegans

Ionizing radiation can cause changes in nervous system function.However,the underlying mechanism remains unclear.In this study,Coenorhabditis elegans(C.elegans)was irradiated with 75 Gy of ^(60)Co whole-body γ radiation.Behavioral indicators(head thrashes,touch avoidance,and foraging),and the development of dopaminergic neurons related to behavioral function,were evaluated to assess the effects of ionizing radiation on nervous system function in C.elegans.Various behaviors were impaired after whole-body irradiation and degeneration of dopamine neurons was observed.This suggests that 75 Gy of γ radiation is sufficient to induce nervous system dysfunction.The genes nhr-76 and crm-1,which are reported to be related to nervous system function in human and mouse,were screened by transcriptome sequencing and bioinformatics analysis after irradiation or sham irradiation.The expression levels of these two genes were increased after radiation.Next,RNAi technology was used to inhibit the expression of crm-1,a gene whose homologs are associated with motor neuron development in other species.Downregulation of crm-1 expression effectively alleviated the deleterious effects of ionizing radiation on head thrashes and touch avoidance.It was also found that the expression level of crm-1 was regulated by the nuclear receptor gene nhr-76.The results of this study suggest that knocking down the expression level of nhr-76 can reduce the expression level of crm-1,while down-regulating the expression level of crm-1 can alleviate behavioral disorders induced by ionizing radiation.Therefore,inhibition of crm-1 may be of interest as a potential therapeutic target for ionizing radiation-induced neurological dysfunction.

航母气流场数值模拟方法研究

由于航速、来风,以及船体运动,航行于海洋环境中的航母船体与上层建筑会影响其气流场,从而影响载机的起降安全.文中分别以载机舰船简化模型及俄制库兹佐涅夫航母为对象,通过数值模拟对比探讨了网格类型、网格密度,以及湍流模型对气流场数值预报结果的影响;并基于数值结果分析了关键位置的流场变化及其对舰载机气动特性的影响.数值模拟结果表明:应用Poly-Hexcore类型的网格在载机舰船气流场数值预报应用中可有效平衡数值求解效率与精度的矛盾,而DES模型较RANS模型在流场细节捕捉方面有较大优势.

Physical dosimetric reconstruction of a case of large area back skin injury due to overexposure in an interventional procedure

To estimate the physical dose of skin and key organs in a case of overexposure during a cardiac interventional procedure.Methods The female patient aged 50 suffered from owerexposure during ardiac interventional therapy in a hospital,Xinxiang city,Henan province,China in January 2020.The mesh-type phantom for the patient was constructed based on the adult mesh-type reference computational phantoms(MRCPs)released by the International Comission on Radiological Protection Publication 145 (ICRP145)and phantom deformation technology.Models of exposure scenario were constructed and simulated with particle and heavy ion transport code system(PHTTS)according to exposure conditions.Resuts:The maximum absorbed dose of key organs/tissues under iradiation in posteroanterior(PA)and 30°left anterior oblique directions(LOA)was 632.4 and 305.6 mGy,respectively.The let lung,heart,and left mammary gland received a larger dose under both iradiation conditions.The ratio of the absorbed dose with and without shielding was a lculated,and the relative difference in most organs was<1%between two directions.The iso-dose curve of the back skin revealed the ditribution of the absorbed dose(0.1-5.2 Gy).The dose estimate of key tssues/organs was higher than the conventional level,especially the local skin,up to 5.2 Gy.Concusions The interventional procedure in this ase resulted in a higher dose.Monte Carlo codes combined with the MRCPs can be employed to estimate physical dose to individuals in concrete irradia tion scenarios.

Research progress on three different types of noncoding RNAs related to ionizing radiation

Non-coding RNAs(ncRNAs)have attracted wide attention in the field of ionizing radiation(IR).They have been found to be involved in cell development,proliferation,differentiation,and apoptosis in both clinical radiotherapy and radiation protection studies.Despite the production of an increasing number of relevant reports in recent years,the molecular mechanisms involved are yet to be clearly understood.In the last few years,ncRNAs have received a lot of research attention,especially microRNAs,long noncoding RNAs,and circular RNAs,which have a well-known association with the development of human disease and are closely related to the biological phenotypic changes caused by IR.With recent developments of research methods,these ncRNAs might play a significant regulatory role in future radiation protection and radiotherapy.This review will summarize the research progress of various types of ncRNAs as biomarkers of IR and potential new targets for radiotherapy,aiming to provide references for future research and the formulation of new strategies.