A coupled computational model of molten steel within the mold was developed,encompassing electromagnetic fields,fluid flow,heat transfer,shell formation,stress,and strain.The model was verified through comparison with...A coupled computational model of molten steel within the mold was developed,encompassing electromagnetic fields,fluid flow,heat transfer,shell formation,stress,and strain.The model was verified through comparison with plant measurements,showing reasonable agreement in electromagnetic field distribution,solidification endpoint,and shell thickness.Results indicate that coordinating the submerged entry nozzle(SEN)and mold electromagnetic stirring(M-EMS)effectively regulates the solidification quality of the initial shell.Adjusting M-EMS current frequency changes the impact position of the molten steel jet from the four-port SEN,while increasing current intensity reduces the jet impact intensity.Adjusting the M-EMS parameters can enhance the initial shell uniformity.Furthermore,in areas directly impacted by the steel jet from the four-port SEN,a relationship between brittle temperature range(BTR)width and total mechanical strain was found,and the larger the BTR width,the smaller the corresponding total mechanical strain.The BTR width provides a discriminant method to avoid hot tearing.Appropriate M-EMS parameters are obtained and applied,and the plant trials show a significant improvement in hot tearing near the surface of round blooms.展开更多
RGD peptides has been used to detect cell surface integrin and direct clinical effective therapeutic drug selection. Herein we report that a quick one step detection of cell surface marker that was realized by a speci...RGD peptides has been used to detect cell surface integrin and direct clinical effective therapeutic drug selection. Herein we report that a quick one step detection of cell surface marker that was realized by a specially designed NiF e-based magnetic biosensing cell chip combined with functionalized magnetic nanoparticles. Magnetic nanoparticles with 20-30 nm in diameter were prepared by coprecipitation and modified with RGD-4C, and the resultant RGD-functionalized magnetic nanoparticles were used for targeting cancer cells cultured on the NiF e-based magnetic biosensing chip and distinguish the amount of cell surface receptor-integrin.Cell lines such as Calu3, Hela, A549, CaF br, HEK293 and HUVEC exhibiting different integrin expression were chosen as test samples. Calu3, Hela, HEK293 and HUVEC cells were successfully identified. This approach has advantages in the qualitative screening test. Compared with traditional method, it is fast, sensitive, low cost,easy-operative, and needs very little human intervention. The novel method has great potential in applications such as fast clinical cell surface marker detection, and diagnosis of early cancer, and can be easily extended to other biomedical applications based on molecular recognition.展开更多
The recurring occurrence of seismic hazards constitutes a significant and imminent threat to subway stations.Consequently,a meticulous assessment of the seismic resilience of subway stations becomes imperative for enh...The recurring occurrence of seismic hazards constitutes a significant and imminent threat to subway stations.Consequently,a meticulous assessment of the seismic resilience of subway stations becomes imperative for enhancing urban safety and ensuring sustained functionality.This study strives to introduce a probabilistic framework tailored to assess the seismic resilience of stations when confronted with seismic hazards.The framework aims to precisely quantify station resilience by determining the integral ratio between the station performance curve and the corresponding station recovery time.To achieve this goal,a series of finite element models of the soil-station system were developed and employed to investigate the impact of site type,seismic intensity,and station structural type on the dynamic response of the station.Then,the seismic fragility functions were generated by developing the relationships between seismic intensity and damage index,taking into account multidimensional uncertainties encompassing factors such as earthquake characteristics and construction quality.The resilience assessment was subsequently conducted based on the station’s fragility and the corresponding economic loss,while also considering the recovery path and recoverability.Additionally,the impacts of diverse factors,including structural characteristics,site types,functional recovery models,and peak ground acceleration(PGA)intensities,on the resilience of stations with distinct structural forms were also discussed.This work contributes to the resilience-based design and management of metro networks to support adaptation to seismic hazards,thereby facilitating the efficient allocation of resources by relevant decision makers.展开更多
Background:Currently,the effect of the 2022 nationwide coronavirus disease 2019(COVID-19)wave on the perioperative prognosis of surgical patients in China is unclear.Thus,we aimed to explore its influence on postopera...Background:Currently,the effect of the 2022 nationwide coronavirus disease 2019(COVID-19)wave on the perioperative prognosis of surgical patients in China is unclear.Thus,we aimed to explore its influence on postoperative morbidity and mortality in surgical patients.Methods:An ambispective cohort study was conducted at Xijing Hospital,China.We collected 10-day time-series data from December 29 until January 7 for the 2018-2022 period.The primary outcome was major postoperative complications(Clavien-Dindo class III-V).The association between COVID-19 exposure and postoperative prognosis was explored by comparing consecutive 5-year data at the population level and by comparing patients with and without COVID-19 exposure at the patient level.Results:The entire cohort consisted of 3350 patients(age:48.5±19.2 years),including 1759 females(52.5%).Overall,961(28.7%)underwent emergency surgery,and 553(16.5%)had COVID-19 exposure(from the 2022 cohort).At the population level,major postoperative complications occurred in 5.9%(42/707),5.7%(53/935),5.1%(46/901),9.4%(11/117),and 22.0%(152/690)patients in the 2018-2022 cohorts,respectively.After adjusting for potential confounding factors,the 2022 cohort(80%patients with COVID-19 history)had a significantly higher postoperative major complication risk than did the 2018 cohort(adjusted risk difference[aRD],14.9%(95%confidence interval[CI],11.5-18.4%);adjusted odds ratio[aOR],8.19(95%CI,5.24-12.81)).At the patient level,the incidence of major postoperative complications was significantly greater in patients with(24.6%,136/553)than that in patients without COVID-19 history(6.0%[168/2797];aRD,17.8%[95%CI,13.6-22.1%];aOR,7.89[95%CI,5.76-10.83]).Secondary outcomes of postoperative pulmonary complications were consistent with primary findings.These findings were verified through sensitivity analyses using time-series data projections and propensity score matching.Conclusion:Based on a single-center observation,patients with recent COVID-19 exposure were likely to have a high incidence of major postoperative complications.Registration:NCT05677815 at https://clinicaltrials.gov/.展开更多
To the Editor:Acute kidney injury(AKI)is a frequent complication of both cardiac and major non-cardiac surgeries.Cardiopulmonary bypass(CPB)-assisted cardiac surgery was associated with a higher incidence of AKI than ...To the Editor:Acute kidney injury(AKI)is a frequent complication of both cardiac and major non-cardiac surgeries.Cardiopulmonary bypass(CPB)-assisted cardiac surgery was associated with a higher incidence of AKI than other surgeries without CPB,suggesting that CPB might be a risk factor for cardiac surgery-associated AKI(CSA-AKI).[1]However,previous studies have demonstrated conflicting results regarding the association of CPB and CSA-AKI,as the diagnosis of AKI has been made according to different criteria.[2-5]The most recent definition of AKI from an AKI Work Group,Kidney Disease:Improving Global Outcomes(KDIGO),allows for the determination of AKI based on a decline in the glomerular filtration rate(GFR)with subsequent increase in serum creatinine or a period of oliguria.[6]We performed a retrospective cohort study to evaluate the association of CPB and postoperative AKI,using the KDIGO definition among patients undergoing on-pump or off-pump coronary artery bypass graft(CABG).展开更多
基金supported by Zhongyuan Special Steel Equipment Manufacturing Co.,Ltd.,China.
文摘A coupled computational model of molten steel within the mold was developed,encompassing electromagnetic fields,fluid flow,heat transfer,shell formation,stress,and strain.The model was verified through comparison with plant measurements,showing reasonable agreement in electromagnetic field distribution,solidification endpoint,and shell thickness.Results indicate that coordinating the submerged entry nozzle(SEN)and mold electromagnetic stirring(M-EMS)effectively regulates the solidification quality of the initial shell.Adjusting M-EMS current frequency changes the impact position of the molten steel jet from the four-port SEN,while increasing current intensity reduces the jet impact intensity.Adjusting the M-EMS parameters can enhance the initial shell uniformity.Furthermore,in areas directly impacted by the steel jet from the four-port SEN,a relationship between brittle temperature range(BTR)width and total mechanical strain was found,and the larger the BTR width,the smaller the corresponding total mechanical strain.The BTR width provides a discriminant method to avoid hot tearing.Appropriate M-EMS parameters are obtained and applied,and the plant trials show a significant improvement in hot tearing near the surface of round blooms.
基金supported by National Key Basic Research Program (973 Project) (No. 2010CB933901 and 2011CB933100)National 863 Hi-tech Project of China (No. 2012AA022703), National Natural Scientific Fund (No. 81225010, 81101169 and 31100717)Shanghai Nano project (13NM1401500), Specialized Research Fund for the Doctoral Program of Higher Education (No. 20110073120072)
文摘RGD peptides has been used to detect cell surface integrin and direct clinical effective therapeutic drug selection. Herein we report that a quick one step detection of cell surface marker that was realized by a specially designed NiF e-based magnetic biosensing cell chip combined with functionalized magnetic nanoparticles. Magnetic nanoparticles with 20-30 nm in diameter were prepared by coprecipitation and modified with RGD-4C, and the resultant RGD-functionalized magnetic nanoparticles were used for targeting cancer cells cultured on the NiF e-based magnetic biosensing chip and distinguish the amount of cell surface receptor-integrin.Cell lines such as Calu3, Hela, A549, CaF br, HEK293 and HUVEC exhibiting different integrin expression were chosen as test samples. Calu3, Hela, HEK293 and HUVEC cells were successfully identified. This approach has advantages in the qualitative screening test. Compared with traditional method, it is fast, sensitive, low cost,easy-operative, and needs very little human intervention. The novel method has great potential in applications such as fast clinical cell surface marker detection, and diagnosis of early cancer, and can be easily extended to other biomedical applications based on molecular recognition.
基金supported by the National Key Research and Development Program of China(No.2021YFF0502200)Shanghai Science and Technology Committee Program(No.22dz1201202)+3 种基金the National Natural Science Foundation of China(Grants No.52408435,52478410)Natural Science Foundation of Chongqing,China(No.CSTB2023NSCQ-MSX0808)Young Elite Scientists Sponsorship Program by CAST(No.2023QNRC001)the Fundamental Research Funds for the Central Universities.
文摘The recurring occurrence of seismic hazards constitutes a significant and imminent threat to subway stations.Consequently,a meticulous assessment of the seismic resilience of subway stations becomes imperative for enhancing urban safety and ensuring sustained functionality.This study strives to introduce a probabilistic framework tailored to assess the seismic resilience of stations when confronted with seismic hazards.The framework aims to precisely quantify station resilience by determining the integral ratio between the station performance curve and the corresponding station recovery time.To achieve this goal,a series of finite element models of the soil-station system were developed and employed to investigate the impact of site type,seismic intensity,and station structural type on the dynamic response of the station.Then,the seismic fragility functions were generated by developing the relationships between seismic intensity and damage index,taking into account multidimensional uncertainties encompassing factors such as earthquake characteristics and construction quality.The resilience assessment was subsequently conducted based on the station’s fragility and the corresponding economic loss,while also considering the recovery path and recoverability.Additionally,the impacts of diverse factors,including structural characteristics,site types,functional recovery models,and peak ground acceleration(PGA)intensities,on the resilience of stations with distinct structural forms were also discussed.This work contributes to the resilience-based design and management of metro networks to support adaptation to seismic hazards,thereby facilitating the efficient allocation of resources by relevant decision makers.
文摘Background:Currently,the effect of the 2022 nationwide coronavirus disease 2019(COVID-19)wave on the perioperative prognosis of surgical patients in China is unclear.Thus,we aimed to explore its influence on postoperative morbidity and mortality in surgical patients.Methods:An ambispective cohort study was conducted at Xijing Hospital,China.We collected 10-day time-series data from December 29 until January 7 for the 2018-2022 period.The primary outcome was major postoperative complications(Clavien-Dindo class III-V).The association between COVID-19 exposure and postoperative prognosis was explored by comparing consecutive 5-year data at the population level and by comparing patients with and without COVID-19 exposure at the patient level.Results:The entire cohort consisted of 3350 patients(age:48.5±19.2 years),including 1759 females(52.5%).Overall,961(28.7%)underwent emergency surgery,and 553(16.5%)had COVID-19 exposure(from the 2022 cohort).At the population level,major postoperative complications occurred in 5.9%(42/707),5.7%(53/935),5.1%(46/901),9.4%(11/117),and 22.0%(152/690)patients in the 2018-2022 cohorts,respectively.After adjusting for potential confounding factors,the 2022 cohort(80%patients with COVID-19 history)had a significantly higher postoperative major complication risk than did the 2018 cohort(adjusted risk difference[aRD],14.9%(95%confidence interval[CI],11.5-18.4%);adjusted odds ratio[aOR],8.19(95%CI,5.24-12.81)).At the patient level,the incidence of major postoperative complications was significantly greater in patients with(24.6%,136/553)than that in patients without COVID-19 history(6.0%[168/2797];aRD,17.8%[95%CI,13.6-22.1%];aOR,7.89[95%CI,5.76-10.83]).Secondary outcomes of postoperative pulmonary complications were consistent with primary findings.These findings were verified through sensitivity analyses using time-series data projections and propensity score matching.Conclusion:Based on a single-center observation,patients with recent COVID-19 exposure were likely to have a high incidence of major postoperative complications.Registration:NCT05677815 at https://clinicaltrials.gov/.
基金Natural Science Foundation of China(No.81970448)
文摘To the Editor:Acute kidney injury(AKI)is a frequent complication of both cardiac and major non-cardiac surgeries.Cardiopulmonary bypass(CPB)-assisted cardiac surgery was associated with a higher incidence of AKI than other surgeries without CPB,suggesting that CPB might be a risk factor for cardiac surgery-associated AKI(CSA-AKI).[1]However,previous studies have demonstrated conflicting results regarding the association of CPB and CSA-AKI,as the diagnosis of AKI has been made according to different criteria.[2-5]The most recent definition of AKI from an AKI Work Group,Kidney Disease:Improving Global Outcomes(KDIGO),allows for the determination of AKI based on a decline in the glomerular filtration rate(GFR)with subsequent increase in serum creatinine or a period of oliguria.[6]We performed a retrospective cohort study to evaluate the association of CPB and postoperative AKI,using the KDIGO definition among patients undergoing on-pump or off-pump coronary artery bypass graft(CABG).
