The response of glutathione S-transferase(GST)in Zostera marina to temperature variation was analyzed at molecular level by cloning the microsomal GST gene and texting the microsomal GST expression regularity under di...The response of glutathione S-transferase(GST)in Zostera marina to temperature variation was analyzed at molecular level by cloning the microsomal GST gene and texting the microsomal GST expression regularity under different temperature.Specific speaking,express ZmGST in Escherichia coli,then purify the recombinant protein and make the thermal stability analysis.Therefore,the experiments were carried out to provide a theoretical basis for the further elaboration to the population degradation mechanisms of Z.marina.In conclusion,the thermostability and the response of ZmGST gene to temperature changes can determine its temperature tolerance range,and affect its resilience in turn.展开更多
Introduction:This study aimed to establish a new predictive model for indoor radon concentrations.Methods:We constructed a radon experimental model using prefabricated block walls and measured surface radon exhalation...Introduction:This study aimed to establish a new predictive model for indoor radon concentrations.Methods:We constructed a radon experimental model using prefabricated block walls and measured surface radon exhalation rates across multi-layer walls.The geometric parameters of various building envelopes(walls,floors,and roofs)were incorporated to calculate indoor radon concentrations from each source.Natural ventilation rates were also considered in developing the indoor radon concentration prediction model.Results:Using closed-loop measurements,we determined the surface radon exhalation rates of prefabricated block walls and established fitting functions for multiple walls under varying temperatures and thicknesses.Based on indoor geometric parameters and natural ventilation rates,we developed a comprehensive prediction model for indoor radon concentrations.The model accurately predicted indoor equilibrium radon concentrations from prefabricated walls(thickness 0.155–0.268 m)at 23℃,with deviations less than 10%from measured values within ventilation rates of 0.115±0.015/h.Conclusions:This scientifically rigorous and practical approach to predicting radon concentration,based on building composition and measurements of radon exhalation rates,enables proactive assessment of indoor radon concentrations and facilitates evidencebased health risk prevention strategies.展开更多
Introduction:Radon(222Rn or 222radon)is a radioactive gas emitted from building materials,foundations,and soil.Children are especially susceptible to radon exposure,underscoring the need to assess indoor radon levels ...Introduction:Radon(222Rn or 222radon)is a radioactive gas emitted from building materials,foundations,and soil.Children are especially susceptible to radon exposure,underscoring the need to assess indoor radon levels in kindergartens.This study monitored radon concentrations in 37 Beijing kindergartens from June to October 2023.Methods:A random sample of 37 kindergartens was selected from 18 administrative districts in Beijing.The indoor radon concentration was measured using the solid track accumulation method,with radon detectors continuously monitored over a 3-month period.Results:The mean indoor radon level in 37 kindergartens,observed at 252 monitoring points,was 84.3 Bq/m^(3),with values varying from 12.9 to 263.5 Bq/m^(3).About 20.2%of points showed radon levels between 100.0 and 200.0 Bq/m^(3),while 2.4%exceeded 200.0 Bq/m^(3).Notably,radon levels were significantly elevated on the ground floor compared to the upper floors.Conclusion:Indoor radon levels in 37 kindergartens remained below the national standard limit of 300.0 Bq/m^(3) for buildings(GB/T 16146-2015).Nonetheless,18.9%of the kindergartens exceeded the 100.0 Bq/m^(3) limit set for new constructions.It is advised to improve radon monitoring in kindergartens and consider developing a national standard for maximum permissible radon levels in such facilities.展开更多
Introduction:Traditional methods for determining radiation dose in nuclear medicine include the Monte Carlo method,the discrete ordinate method,and the point kernel integration method.This study presents a new mathema...Introduction:Traditional methods for determining radiation dose in nuclear medicine include the Monte Carlo method,the discrete ordinate method,and the point kernel integration method.This study presents a new mathematical model for predicting the radiation dose rate in the vicinity of nuclear medicine patients.Methods:A new algorithm was created by combining the physical model of“cylinder superposition”of the human body with integral analysis to assess the radiation dose rate in the vicinity of nuclear medicine patients.Results:The model accurately predicted radiation dose rates within distances of 0.1–3.0 m,with a deviation of less than 11%compared to observed rates.The model demonstrated greater accuracy at shorter distances from the radiation source,with a deviation of only 1.55%from observed values at 0.1 m.Discussion:The model proposed in this study effectively represents the spatial and temporal distribution of the radiation field around nuclear medicine patients and demonstrates good agreement with actual measurements.This model has the potential to serve as a radiation dose rate alert system in hospital environments.展开更多
基金The Open Fund of Key Laboratory of Marine Spil Oil Identification and Damage Assessment Technology,State Oceanic Administration under contract No.201704the Shandong Provincial Natural Science Foundation of China under contract No.ZR2018MD020
文摘The response of glutathione S-transferase(GST)in Zostera marina to temperature variation was analyzed at molecular level by cloning the microsomal GST gene and texting the microsomal GST expression regularity under different temperature.Specific speaking,express ZmGST in Escherichia coli,then purify the recombinant protein and make the thermal stability analysis.Therefore,the experiments were carried out to provide a theoretical basis for the further elaboration to the population degradation mechanisms of Z.marina.In conclusion,the thermostability and the response of ZmGST gene to temperature changes can determine its temperature tolerance range,and affect its resilience in turn.
文摘Introduction:This study aimed to establish a new predictive model for indoor radon concentrations.Methods:We constructed a radon experimental model using prefabricated block walls and measured surface radon exhalation rates across multi-layer walls.The geometric parameters of various building envelopes(walls,floors,and roofs)were incorporated to calculate indoor radon concentrations from each source.Natural ventilation rates were also considered in developing the indoor radon concentration prediction model.Results:Using closed-loop measurements,we determined the surface radon exhalation rates of prefabricated block walls and established fitting functions for multiple walls under varying temperatures and thicknesses.Based on indoor geometric parameters and natural ventilation rates,we developed a comprehensive prediction model for indoor radon concentrations.The model accurately predicted indoor equilibrium radon concentrations from prefabricated walls(thickness 0.155–0.268 m)at 23℃,with deviations less than 10%from measured values within ventilation rates of 0.115±0.015/h.Conclusions:This scientifically rigorous and practical approach to predicting radon concentration,based on building composition and measurements of radon exhalation rates,enables proactive assessment of indoor radon concentrations and facilitates evidencebased health risk prevention strategies.
基金Supported by the Construction Project of High-Level Public Health Technical Personnel in Beijing,China(Academic Leader-01-20).
文摘Introduction:Radon(222Rn or 222radon)is a radioactive gas emitted from building materials,foundations,and soil.Children are especially susceptible to radon exposure,underscoring the need to assess indoor radon levels in kindergartens.This study monitored radon concentrations in 37 Beijing kindergartens from June to October 2023.Methods:A random sample of 37 kindergartens was selected from 18 administrative districts in Beijing.The indoor radon concentration was measured using the solid track accumulation method,with radon detectors continuously monitored over a 3-month period.Results:The mean indoor radon level in 37 kindergartens,observed at 252 monitoring points,was 84.3 Bq/m^(3),with values varying from 12.9 to 263.5 Bq/m^(3).About 20.2%of points showed radon levels between 100.0 and 200.0 Bq/m^(3),while 2.4%exceeded 200.0 Bq/m^(3).Notably,radon levels were significantly elevated on the ground floor compared to the upper floors.Conclusion:Indoor radon levels in 37 kindergartens remained below the national standard limit of 300.0 Bq/m^(3) for buildings(GB/T 16146-2015).Nonetheless,18.9%of the kindergartens exceeded the 100.0 Bq/m^(3) limit set for new constructions.It is advised to improve radon monitoring in kindergartens and consider developing a national standard for maximum permissible radon levels in such facilities.
基金Supported by the National Natural Science Foundation of China(grant nos.31770907,31640022 and 31170806)the Beijing Natural Science Foundation(grant no.7172146).
文摘Introduction:Traditional methods for determining radiation dose in nuclear medicine include the Monte Carlo method,the discrete ordinate method,and the point kernel integration method.This study presents a new mathematical model for predicting the radiation dose rate in the vicinity of nuclear medicine patients.Methods:A new algorithm was created by combining the physical model of“cylinder superposition”of the human body with integral analysis to assess the radiation dose rate in the vicinity of nuclear medicine patients.Results:The model accurately predicted radiation dose rates within distances of 0.1–3.0 m,with a deviation of less than 11%compared to observed rates.The model demonstrated greater accuracy at shorter distances from the radiation source,with a deviation of only 1.55%from observed values at 0.1 m.Discussion:The model proposed in this study effectively represents the spatial and temporal distribution of the radiation field around nuclear medicine patients and demonstrates good agreement with actual measurements.This model has the potential to serve as a radiation dose rate alert system in hospital environments.
