To guarantee the blue skies for the 2022 Winter Olympics held in Beijing and Zhangjiakou from February 4 to 20,Beijing and its surrounding areas adopted a series of emission control measures.This provides an opportuni...To guarantee the blue skies for the 2022 Winter Olympics held in Beijing and Zhangjiakou from February 4 to 20,Beijing and its surrounding areas adopted a series of emission control measures.This provides an opportunity to determine the impacts of large-scale temporary control measures on the air quality in Beijing during this special period.Here,we applied the WRF-CMAQ model to quantify the contributions of emission reduction measures and meteorological conditions.Results show that meteorological conditions in 2022 decreased PM_(2.5)in Beijing by 6.9 and 11.8μg/m^(3)relative to 2021 under the scenarios with and without emission reductions,respectively.Strict emission reduction measures implemented in Beijing and seven neighboring provinces resulted in an average decrease of 13.0μg/m^(3)(-41.2%)in PM_(2.5)in Beijing.Over the entire period,local emission reductions contributed more to good air quality in Beijing than nonlocal emission reductions.Under the emission reduction scenario,local,controlled regions,other regions,and boundary conditions contributed 47.7%,42.0%,5.3%,and 5.0%to the PM_(2.5)concentrations in Beijing,respectively.The results indicate that during the cleaning period with the air masses from the northwest,the abatements of PM_(2.5)were mainly caused by local emission reductions.However,during the potential pollution period with the air masses from the east-northeast and west-southwest,the abatements of PM_(2.5)were caused by both local and nonlocal emission reductions almost equally.This implies that regional coordinated prevention and control strategies need to be arranged scientifically and rationally when heavy pollution events are forecasted.展开更多
BACKGROUND Over the last decade,the treatment options for inflammatory bowel disease(IBD)have significantly progressed with the emergence of new medications designed to target various immune pathways and mitigate infl...BACKGROUND Over the last decade,the treatment options for inflammatory bowel disease(IBD)have significantly progressed with the emergence of new medications designed to target various immune pathways and mitigate inflammation.Adalimumab(ADA)is a tumor necrosis factor alpha antagonist and stands as an effective treatment for IBD.In April 2021,the province of British Columbia implemented a mandatory non-medical switch policy of the ADA originator Humira®to ADA biosimilars.Biosimilars offer a potential cost-effective,safe,and efficacious alternative to the originator,yet there remains limited real-world evidence on long-term outcomes of ADA non-medical switching in IBD.AIM To assess the long-term outcomes of non-medical switching from the ADA originator Humira®to an ADA biosimilar among IBD patients.METHODS A retrospective observational chart review study was conducted on IBD patients eligible for the provincially mandated non-medical switch to an ADA biosimilar.The primary outcome was treatment persistence at 30 months post-switch.Secondary outcomes included the proportion of and reasons for therapy alteration or ADA discontinuation,loss of response(LOR)rates,adverse events(AE),and clinical and biochemical remission status.Patients who remained on the originator throughout the switch period,through compassionate support or private pay,constituted the comparison group.RESULTS Patients in the originator(n=43)and biosimilar switch(n=228)groups displayed similar demographics and baseline disease characteristics.By the study endpoint of 30 months,there was no difference in the rate of treatment persistence in either group(n=36,83.7%originator group vs n=201,88.2%biosimilar group,P=0.451).Treatment persistence demonstrated similar rates of discontinuation between both study groups(log-rank P=0.543).There was a numerical but not statistically significant difference in rates of adverse outcomes between either group(39.5%originator vs 28.9%biosimilars,P=0.206).This included comparable rates of LOR(27.9%vs 17.5%)or AE(11.6%vs 11.4%)between the originator and biosimilar cohorts,respectively.C-reactive protein and fecal calprotectin levels were similar one year pre-and post-switch.CONCLUSION These data support the long-term efficacy and safety of non-medical ADA switching in IBD and will help inform patients and physicians in jurisdictions currently undergoing biosimilar switching.展开更多
The microphysical characteristics of wintertime cold clouds in North China were investigated from 22 aircraft observation flights from 2014 to 2017,2020,and 2021.The clouds were generated by mesoscale weather systems ...The microphysical characteristics of wintertime cold clouds in North China were investigated from 22 aircraft observation flights from 2014 to 2017,2020,and 2021.The clouds were generated by mesoscale weather systems with little orographic component.Over the mixed-phase temperature range(–40℃to 0℃),the average fraction of liquid,mixedphase,and ice cloud was 4.9%,23.3%,and 71.8%,respectively,and the probability distribution of ice mass fraction was a half-U-shape,suggesting that ice cloud was the primary cloud type.The wintertime mixed-phase clouds in North China were characterized by large cloud droplet number concentration,small liquid water content(LWC),and small effective diameter of cloud droplets.The main reason for larger cloud droplet number concentration and smaller effective diameter of cloud droplets was the heavy pollution in winter in North China,while for smaller LWC was the lower temperature during flights and the difference in air mass type.With the temperature increasing,cloud droplet number concentration,LWC,and the size of ice particles increased,but ice number concentration and effective diameter of cloud droplets decreased,similar to other mid-latitude regions,indicating the similarity in the temperature dependence of cloud properties of mixed-phase clouds.The variation of the cloud properties and ice habit at different temperatures indicated the operation of the aggregation and riming processes,which were commonly present in the wintertime mixed-phase clouds.This study fills a gap in the aircraft observation of wintertime cold clouds in North China.展开更多
Based on the satellite retrieval methodology, the spectral characteristics and cloud microphysical properties were analyzed that included brightness temperatures of Channels 4 and 5, and their brightness temperature d...Based on the satellite retrieval methodology, the spectral characteristics and cloud microphysical properties were analyzed that included brightness temperatures of Channels 4 and 5, and their brightness temperature difference （BTD）, the particle effective radius of seeded cloud track caused by an operational cloud seeding and the microphysical effects of cloud seeding were revealed by the comparisons of their differences inside and outside the seeded track. The cloud track was actually a cloud channel reaching 1.5-km deep and 14-km wide lasting for more than 80 min. The effective radius of ambient clouds was 10-15 μm, while that within the cloud track ranged from 15 to 26 μm. The ambient clouds were composed of supercooled droplets, and the composition of the cloud within the seeding track was ice. With respect to the rather stable reflectance of two ambient sides around the track, the visible spectral reflectance in the cloud track varied at least 10%, and reached a maximum of 35%, the reflectance of 3.7 μm in the seeded track relatively decreased at least 10%. As cloud seeding advanced, the width and depth were gradually increased. Simultaneously the cloud top temperature within the track became progressively warmer with respect to the ambient clouds, and the maximum temperature differences reached 4.2 and 3.9℃ at the first seeding position for Channels 4 and 5. In addition, the BTD in the track also increased steadily to a maximum of 1.4℃, compared with 0.2-0.4℃ of the ambient clouds. The evidence that the seeded cloud became thinner comes from the visible image showing a channel, the warming of the cloud tops, and the increase of BTD in the seeded track. The seeded cloud became thinner mainly because the cloud top descended and it lost water to precipitation throughout its depth. For this cloud seeding case, the glaciation became apparent at cloud tops about 22 min after seeding. The formation of a cloud track in the supercooled stratiform clouds was mainly because that the seeded cloud volume glaciated into ice hydrometeors that precipitated and so lowered cloud top height. A thin line of new water clouds formed in the middle of the seeded track between 38 and 63 min after seeding, probably as a result of rising motion induced by the released latent heat of freezing. These clouds disappeared in the earlier segments of the seeded track, which suggested that the maturation of the seeding track was associated with its narrowing and eventual dissipation due to expansion of the tops of the ambient clouds from the sides inward.展开更多
基金supported by the National Natural Science Foundation of China (Nos.42175084,21577126,and 41561144004)the Department of Science and Technology of China (Nos.2018YFC0213506,2018YFC0213503,and 2016YFC0202702)+4 种基金the National Research Program for Key Issues in Air Pollution Control in China (No.DQGG0107)supported by the“Zhejiang 1000 Talent Plan”and Research Center for Air Pollution and Health in Zhejiang UniversityPengfei Li is supported by the National Natural Science Foundation of China (No.22006030)the Initiation Fund for Introducing Talents of Hebei Agricultural University (No.412201904)the Hebei Youth Top Q15 Fund (No.BJ2020032)。
文摘To guarantee the blue skies for the 2022 Winter Olympics held in Beijing and Zhangjiakou from February 4 to 20,Beijing and its surrounding areas adopted a series of emission control measures.This provides an opportunity to determine the impacts of large-scale temporary control measures on the air quality in Beijing during this special period.Here,we applied the WRF-CMAQ model to quantify the contributions of emission reduction measures and meteorological conditions.Results show that meteorological conditions in 2022 decreased PM_(2.5)in Beijing by 6.9 and 11.8μg/m^(3)relative to 2021 under the scenarios with and without emission reductions,respectively.Strict emission reduction measures implemented in Beijing and seven neighboring provinces resulted in an average decrease of 13.0μg/m^(3)(-41.2%)in PM_(2.5)in Beijing.Over the entire period,local emission reductions contributed more to good air quality in Beijing than nonlocal emission reductions.Under the emission reduction scenario,local,controlled regions,other regions,and boundary conditions contributed 47.7%,42.0%,5.3%,and 5.0%to the PM_(2.5)concentrations in Beijing,respectively.The results indicate that during the cleaning period with the air masses from the northwest,the abatements of PM_(2.5)were mainly caused by local emission reductions.However,during the potential pollution period with the air masses from the east-northeast and west-southwest,the abatements of PM_(2.5)were caused by both local and nonlocal emission reductions almost equally.This implies that regional coordinated prevention and control strategies need to be arranged scientifically and rationally when heavy pollution events are forecasted.
文摘BACKGROUND Over the last decade,the treatment options for inflammatory bowel disease(IBD)have significantly progressed with the emergence of new medications designed to target various immune pathways and mitigate inflammation.Adalimumab(ADA)is a tumor necrosis factor alpha antagonist and stands as an effective treatment for IBD.In April 2021,the province of British Columbia implemented a mandatory non-medical switch policy of the ADA originator Humira®to ADA biosimilars.Biosimilars offer a potential cost-effective,safe,and efficacious alternative to the originator,yet there remains limited real-world evidence on long-term outcomes of ADA non-medical switching in IBD.AIM To assess the long-term outcomes of non-medical switching from the ADA originator Humira®to an ADA biosimilar among IBD patients.METHODS A retrospective observational chart review study was conducted on IBD patients eligible for the provincially mandated non-medical switch to an ADA biosimilar.The primary outcome was treatment persistence at 30 months post-switch.Secondary outcomes included the proportion of and reasons for therapy alteration or ADA discontinuation,loss of response(LOR)rates,adverse events(AE),and clinical and biochemical remission status.Patients who remained on the originator throughout the switch period,through compassionate support or private pay,constituted the comparison group.RESULTS Patients in the originator(n=43)and biosimilar switch(n=228)groups displayed similar demographics and baseline disease characteristics.By the study endpoint of 30 months,there was no difference in the rate of treatment persistence in either group(n=36,83.7%originator group vs n=201,88.2%biosimilar group,P=0.451).Treatment persistence demonstrated similar rates of discontinuation between both study groups(log-rank P=0.543).There was a numerical but not statistically significant difference in rates of adverse outcomes between either group(39.5%originator vs 28.9%biosimilars,P=0.206).This included comparable rates of LOR(27.9%vs 17.5%)or AE(11.6%vs 11.4%)between the originator and biosimilar cohorts,respectively.C-reactive protein and fecal calprotectin levels were similar one year pre-and post-switch.CONCLUSION These data support the long-term efficacy and safety of non-medical ADA switching in IBD and will help inform patients and physicians in jurisdictions currently undergoing biosimilar switching.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41925023, 91744208, 41575073, 41621005, and 42075084)by the Ministry of Science and Technology of the People’s Republic of China (Grant Nos. 2017YFA0604002 and 2016YFC0200503)supported by the Collaborative Innovation Center of Climate Change, Jiangsu Province
文摘The microphysical characteristics of wintertime cold clouds in North China were investigated from 22 aircraft observation flights from 2014 to 2017,2020,and 2021.The clouds were generated by mesoscale weather systems with little orographic component.Over the mixed-phase temperature range(–40℃to 0℃),the average fraction of liquid,mixedphase,and ice cloud was 4.9%,23.3%,and 71.8%,respectively,and the probability distribution of ice mass fraction was a half-U-shape,suggesting that ice cloud was the primary cloud type.The wintertime mixed-phase clouds in North China were characterized by large cloud droplet number concentration,small liquid water content(LWC),and small effective diameter of cloud droplets.The main reason for larger cloud droplet number concentration and smaller effective diameter of cloud droplets was the heavy pollution in winter in North China,while for smaller LWC was the lower temperature during flights and the difference in air mass type.With the temperature increasing,cloud droplet number concentration,LWC,and the size of ice particles increased,but ice number concentration and effective diameter of cloud droplets decreased,similar to other mid-latitude regions,indicating the similarity in the temperature dependence of cloud properties of mixed-phase clouds.The variation of the cloud properties and ice habit at different temperatures indicated the operation of the aggregation and riming processes,which were commonly present in the wintertime mixed-phase clouds.This study fills a gap in the aircraft observation of wintertime cold clouds in North China.
基金the National Natural Science Foundation of China under Grant No. 40575004the Chinese Ministry of Science and Technology (Grant 2005DIB3J099).
文摘Based on the satellite retrieval methodology, the spectral characteristics and cloud microphysical properties were analyzed that included brightness temperatures of Channels 4 and 5, and their brightness temperature difference （BTD）, the particle effective radius of seeded cloud track caused by an operational cloud seeding and the microphysical effects of cloud seeding were revealed by the comparisons of their differences inside and outside the seeded track. The cloud track was actually a cloud channel reaching 1.5-km deep and 14-km wide lasting for more than 80 min. The effective radius of ambient clouds was 10-15 μm, while that within the cloud track ranged from 15 to 26 μm. The ambient clouds were composed of supercooled droplets, and the composition of the cloud within the seeding track was ice. With respect to the rather stable reflectance of two ambient sides around the track, the visible spectral reflectance in the cloud track varied at least 10%, and reached a maximum of 35%, the reflectance of 3.7 μm in the seeded track relatively decreased at least 10%. As cloud seeding advanced, the width and depth were gradually increased. Simultaneously the cloud top temperature within the track became progressively warmer with respect to the ambient clouds, and the maximum temperature differences reached 4.2 and 3.9℃ at the first seeding position for Channels 4 and 5. In addition, the BTD in the track also increased steadily to a maximum of 1.4℃, compared with 0.2-0.4℃ of the ambient clouds. The evidence that the seeded cloud became thinner comes from the visible image showing a channel, the warming of the cloud tops, and the increase of BTD in the seeded track. The seeded cloud became thinner mainly because the cloud top descended and it lost water to precipitation throughout its depth. For this cloud seeding case, the glaciation became apparent at cloud tops about 22 min after seeding. The formation of a cloud track in the supercooled stratiform clouds was mainly because that the seeded cloud volume glaciated into ice hydrometeors that precipitated and so lowered cloud top height. A thin line of new water clouds formed in the middle of the seeded track between 38 and 63 min after seeding, probably as a result of rising motion induced by the released latent heat of freezing. These clouds disappeared in the earlier segments of the seeded track, which suggested that the maturation of the seeding track was associated with its narrowing and eventual dissipation due to expansion of the tops of the ambient clouds from the sides inward.
