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Harper Cain posted an update 1 day, 1 hour ago
During the operation of high-energy proton accelerators, the air in the tunnel is activated with the production of radionuclides. For CSNS (China Spallation Neutron Source), the first pulsed neutron source in China for multidisciplinary research, an online air activation monitoring system was developed to evaluate the radiation safety of the staff and the public, which consisted of a NaI detector, Pb shielding, an MB container and a control system. With the monitoring system, gamma spectra of the activated air from controlled areas are measured, and the activity concentration and immersion dose rates of radionuclides in air are calculated and displayed in real time. The system has been in stable operation since February 2020, and results have been obtained for the evaluation of the radiation risk from activated air.Advanced nuclear reactor designs and advanced fuel types offer safety features that may reduce environmental consequences in an accident scenario when compared to conventional reactors and fuels. One advanced reactor fuel is tri-structural isotropic (TRISO) fuel particles which are approximately 0.9 mm in diameter. TRISO particle mobility, assuming the particle is unruptured and the encapsulated radionuclides are contained, was explored by a theoretical examination of transport through atmosphere, soil and groundwater, surface water, and non-human biota pathways. TRISO particles are too large and dense to travel in the atmosphere except under extreme conditions. TRISO particles are also too large to penetrate most soil profiles and so cannot be transported to or by groundwater. TRISO particles will settle out of the water column in surface waters and thus the transport will depend on the energy of the water body (e.g., waves or floods). TRISO particles could be transported by non-human biota. The size of TRISO particles could allow them to be intentionally ingested by non-human biota as a gastrolith or mimic something typical in an organism’s diet. Generally, TRISO particles will have reduced environmental mobility compared to releases of radionuclides in the event of a conventional nuclear reactor accident. The extent of transport has implications in emergency planning zone designations and other considerations for licensing and deploying TRISO-fueled reactors. Further research and experimental work exploring TRISO particle mobility is required to understand the full environmental mobility of TRISO particles in the environment.Radioxenon activity concentrations are monitored globally using the International Monitoring System (IMS) of the Comprehensive Nuclear-Test-Ban Treaty Organisation, improving the monitoring community’s ability to detect radionuclide signatures from an underground nuclear test (UNT). An IMS-like noble gas system is in operation at AWE (Aldermaston, UK) and can collect and measure radioxenon isotopes in environmental air samples. When operated in this mode, data produced is analysed at the UK National Data Centre (NDC) and significant detection events are flagged for further investigation. This work discusses a number of significant detection events analysed using the operational system deployed at the UK NDC, which includes atmospheric transport simulations and a real-time stack-monitoring data feed from the nearest medical isotope production facility in Belgium. A comparison of the expected radionuclide contributions with measured detections is presented, including a comparison of the isotopic ratios for the radioxenon isotopes of interest (133Xe, 131mXe, 133mXe, 135Xe).Maternal smoking during pregnancy can induce permanent changes in neonatal inflammation, which will result in lifelong implications. An original study of data from GSE96978, composed of 2 subseries (GSE96976 and GSE96977), investigated genome-wide changes in ELT cells, the lungs of mouse dams and their juvenile offspring and focused on finding an in vitro alternative as a human tissue-based replacement for the use of animals. Therefore, the study only analyzed the similarities of GO terms between ELT cells and dams. However, the relationship between differentially expressed genes (DEGs) in dams and offspring was not investigated. The present study aimed to identify the key molecules involved in maternal smoking-induced dam and offspring lung injuries. Data from GSE96977 were downloaded from Gene Expression Omnibus (GEO) data sets. In our study, differentially expressed genes (DEGs) in dams and offspring were reanalyzed using the limma package. The results of Gene Set Enrichment Analysis (GSEA) showed that the DEGs in the lungs of dams were significantly enriched in immune-related functions and those in the lungs of offspring were enriched in cell growth. Furthermore, a total of 90 DEGs shared in the dam and offspring datasets were screened out. In addition, most of these DEGs were enriched in cytokine and cytokine receptor interaction KEGG pathways. Furthermore, protein-protein interaction (PPI) network analysis screened out 4 core genes in cluster 1. SR18662 order In addition, the miRNAs related to these core genes were predicted, and mmu-miR-1903 was screened out. Taken together, our data indicate that inflammatory responses may play an important role in maternal smoking induced lung injuries in dams and offspring. Furthermore, mmu-miR-1903 is a potential epigenetic biomarker of lung inflammation in the offspring of dams who smoked during pregnancy. In conclusion, by screening shared differential genes, we only need to detect maternal genes to predict maternal smoking-induced lung injuries in offspring.Agricultural soil is highly susceptible to manure contamination and thus is a potential source for the spread of pathogens and antibiotic resistance genes (ARGs). Routine monitoring fecal contamination in agricultural soil can reduce the manure-derived ARG contaminations. This study investigated the distribution of crAssphage, a highly human-specific indicator of fecal pollution, in agricultural soils in the Yangtze River Delta (YRD) of China, and its potential in serving as an indicator of soil ARGs. CrAssphage was indeed strongly correlated with the abundance of soil ARGs, and particularly tetracycline resistance gene tetW (rho = 0.55, p less then 0.01). Meanwhile, with the increasing of crAssphage abundance, the frequency of multiple abundant ARGs is also increased. When the relative abundance of crAssphage in soil samples exceeded 4.94 × 10-4 copies per copy of the 16S rRNA gene, there would be more than three types of co-existing ARGs. Regional differences in crAssphage and ARGs abundances were observed for samples collected from Zhejiang, Shanghai, Jiangsu, and Anhui in the YRD, indicating different levels of fecal pollution therein.