The cardiac microenvironment profoundly restricts the efficacy of myocardial regeneration tactics for the treatment of myocardial infarction(MI).A prospective approach for MI therapeutics encompasses the combined stra...The cardiac microenvironment profoundly restricts the efficacy of myocardial regeneration tactics for the treatment of myocardial infarction(MI).A prospective approach for MI therapeutics encompasses the combined strategy of scavenging reactive oxygen species(ROS)to alleviate oxidative stress injury and facilitating macrophage polarization towards the regenerative M2 phenotype.In this investigation,we fabricated a ROSsensitive hydrogel engineered to deliver our previously engineered IL-1β-VHH for myocardial restoration.In mouse and rat models of myocardial infarction,the therapeutic gel was injected into the pericardial cavity,effectively disseminated over the heart surface,forming an in situ epicardial patch.The IL-1β-VHH released from the hydrogel exhibited penetrative potential into the myocardium.Our results imply that this infarct-targeting gel can adhere to the damaged cardiac tissue and augment the quantity of anti-IL-1βantibodies.Moreover,the anti-IL-1βhydrogel safeguards cardiomyocytes from apoptosis by neutralizing IL-1βand inducing M2-type polarization within the myocardial infarction regions,thereby facilitating therapeutic cardiac repair.Our results emphasize the effectiveness of this synergistic comprehensive treatment modality in the management of MI and showcase its considerable potential for promoting recovery in infarcted hearts.展开更多
Extending the atmospheric model top to high altitude is important for simulation of upper atmospheric phenomena,such as the stratospheric quasi-biennial oscillation.The high-top version of the Institute of Atmospheric...Extending the atmospheric model top to high altitude is important for simulation of upper atmospheric phenomena,such as the stratospheric quasi-biennial oscillation.The high-top version of the Institute of Atmospheric Physics Atmospheric General Circulation Model with 91 vertical layers(IAP-AGCML91)extends to the mesopause at about 0.01 hPa(~80 km).The high-top model with a fully resolved stratosphere is found to simulate a warmer stratosphere than the low-top version,except near the South Pole,thus reducing its overall cold bias in the stratosphere,and significantly in the upper stratosphere.This sensitivity is shown to be consistent with two separate mechanisms:larger shortwave heating and larger poleward stratospheric meridional eddy heat flux in the hightop model than in the low-top model.Results indicate a significant influence of vertical resolution and model top on climate simulations in IAP-AGCM.展开更多
Cloud radiative kernels were built by BCC_RAD(Beijing Climate Center radiative transfer model)radiative transfer code.Then,short-term cloud feedback and its mechanisms in East Asia(0.5°S−60.5°N,69.5°−15...Cloud radiative kernels were built by BCC_RAD(Beijing Climate Center radiative transfer model)radiative transfer code.Then,short-term cloud feedback and its mechanisms in East Asia(0.5°S−60.5°N,69.5°−150.5°E)were analyzed quantitatively using the kernels combined with MODIS satellite data from July 2002 to June 2018.According to the surface and monsoon types,four subregions in East Asia-the Tibetan Plateau,northwest,temperate monsoon(TM),and subtropical monsoon(SM)—were selected.The average longwave,shortwave,and net cloud feedbacks in East Asia are−0.68±1.20,1.34±1.08,and 0.66±0.40 W m^−2 K^−1(±2σ),respectively,among which the net feedback is dominated by the positive shortwave feedback.Positive feedback in SM is the strongest of all subregions,mainly due to the contributions of nimbostratus and stratus.In East Asia,short-term feedback in spring is primarily caused by marine stratus in SM,in summer is primarily driven by deep convective cloud in TM,in autumn is mainly caused by land nimbostratus in SM,and in winter is mainly driven by land stratus in SM.Cloud feedback in East Asia is chiefly driven by decreases in mid-level and low cloud fraction owing to the changes in relative humidity,and a decrease in low cloud optical thickness due to the changes in cloud water content.展开更多
The quasi-biennial oscillation(QBO),a dominant mode of the equatorial stratospheric(~100–1 hPa)variability,is known to impact tropospheric circulation in the middle and high latitudes.Yet,its realistic simulation in ...The quasi-biennial oscillation(QBO),a dominant mode of the equatorial stratospheric(~100–1 hPa)variability,is known to impact tropospheric circulation in the middle and high latitudes.Yet,its realistic simulation in general circulation models remains a challenge.The authors examine the simulated QBO in the 69-layer version of the Institute of Atmospheric Physics Atmospheric General Circulation Model(IAP-AGCML69)and analyze its momentum budget.The authors find that the QBO is primarily caused by parameterized gravity-wave forcing due to tropospheric convection,but the downward propagation of the momentum source is significantly offset by the upward advection of zonal wind by the equatorial upwelling in the stratosphere.Resolved-scale waves act as a positive contribution to the total zonal wind tendency of the QBO over the equator with comparable magnitude to the gravity-wave forcing in the upper stratosphere.Results provide insights into the mechanism of the QBO and possible causes of differences in models.展开更多
The origin and spread of agriculture facilitated a decline in human mobility and eventually led to a predominantly sedentary lifestyle globally,including on the Tibetan Plateau.Previous studies have proposed an evolut...The origin and spread of agriculture facilitated a decline in human mobility and eventually led to a predominantly sedentary lifestyle globally,including on the Tibetan Plateau.Previous studies have proposed an evolution of prehistoric agriculture,from millet-based to barley-based farming.However,details regarding the process are vague.Here,we present diachronic changes in cropping structure from Xizang on the basis of a quantitative analysis of archaeobotanical remains from 12 sites located in southeastern Xizang.The advent of agriculture in Xizang began in the southeastern region around 4800 cal a BP and resulted in a quick spread of millet agriculture from the Hengduan Mountains to the Yarlung Zangbo River region.Subsequently,the introduction of barley and wheat to Xizang led to the transformation of millet-based farming into mixed farming after 3600 cal a BP.Eventually,around 3000 cal a BP,barley and wheat dominated across the entire Xizang with declining occurrences of millet.It took more than 600 years for barley and wheat to dominate in the Tibetan cropping system,which may reflect the time required for these exotic species to adapt physiologically to their new niche.In addition to the diachronic changes in crop farming,the ratio of barley to wheat and foxtail millet to broomcorn millet also varied at different elevations possibly due to local environmental variations and the crops’physiological requirements.展开更多
Millet agriculture,which originated in northern China,alongside rice agriculture,have nurtured the Chinese civilization.Prehistoric manuring practices likely promoted and maintained sustainable millet agricultural pro...Millet agriculture,which originated in northern China,alongside rice agriculture,have nurtured the Chinese civilization.Prehistoric manuring practices likely promoted and maintained sustainable millet agricultural production in the loess area of northern China.However,ongoing controversy exists regarding the indicators of prehistoric manuring intensity of foxtail millet(Setaria italica)and common millet(Panicum miliaceum).Here,we present the results of pot and field fertilization experiments on two millet types.Our findings suggest that manuring can significantly increase the δ^(15)N values of foxtail millet,and its δ^(15)N values increase with increasing manuring levels.The δ^(15)N values of foxtail millet leaves are systematically greater than those of grains by approximately 1.6‰.Manuring could have a long-term residual impact on increasing the δ^(15)N values of soil and millet crops.Combined with previous crop fertilization experiment results,we propose that the impact of manuring on the δ^(15)N values of non-nitrogen-fixing crops is roughly consistent.The δ^(15)N value and amount of manure are key factors determining the extent of change in plant δ^(15)N values.The millet grain δ^(15)N values can serve as reliable indicators of manuring practices.Finally,we provide an interpretive framework for assessing the correlation between manuring levels and the δ^(15)N values of archaeological millet remains.The δ^(15)N values of ancient millet grains suggest widespread and intensive manuring practices in prehistoric millet agriculture in northern China,spanning from the early Yangshao period to the Longshan period.展开更多
The present study investigates meteorological conditions for the day-to-day changes of particulate matter （PM） concentration in Beijing city during the period 2008-2015. The local relationship of PM concentration to...The present study investigates meteorological conditions for the day-to-day changes of particulate matter （PM） concentration in Beijing city during the period 2008-2015. The local relationship of PM concentration to surface air temperature, pressure, wind speed, and relative humidity displays seasonal changes and year-to-year variations. The average correlation coefficient with PMI0 in spring, summer, fall, and winter is 0.45, 0.40, 0.38, and 0.30 for air tem- perature; -0.45, -0.05, -0.40, and -0.45 for pressure; 0.13, 0.04, 0.53, and 0.50 for relative humidity; and -0.18, -0.11, -0.45, and -0.33 for wind speed. A higher correlation with wind speed is obtained when wind speed leads by halfa day. The heavily polluted and clean days, which are defined as the top and bottom 10% of the PM values, show obvious differences in the regional distribution of air temperature, pressure, and wind. Polluted days correspond to higher air temperature in all the four seasons, lower sea level pressure and anomalous southerly winds to the south and east of Beijing in spring, fall, and winter, and a northwest-southeast contrast in the pressure anomaly and anom- alous southerly winds in summer. Higher relative humidity is observed on polluted days in fall and winter. The pol- luted days are preceded by an anomalous cyclone moving from the northwest, accompanied by lower pressure and higher air temperature, in all four seasons. This feature indicates the impacts of moving weather systems on local meteorological conditions for day-to-day air quality changes in Beijing.展开更多
We compared the regional synoptic patterns and local meteorological conditions during persistent and non-persistent pollution events in Beijing using US NCEP–Department of Energy reanalysis outputs and observations f...We compared the regional synoptic patterns and local meteorological conditions during persistent and non-persistent pollution events in Beijing using US NCEP–Department of Energy reanalysis outputs and observations from meteorological stations. The analysis focused on the impacts of high-frequency（period 〈 90 days） variations in meteorological conditions on persistent pollution events（those lasting for at least 3 days）. Persistent pollution events tended to occur in association with slow-moving weather systems producing stagnant weather conditions, whereas rapidly moving weather systems caused a dramatic change in the local weather conditions so that the pollution event was short-lived. Although Beijing was under the influence of anomalous southerly winds in all four seasons during pollution events, notable differences were identified in the regional patterns of sea-level pressure and local anomalies in relative humidity among persistent pollution events in different seasons. A region of lower pressure was present to the north of Beijing in spring, fall, and winter, whereas regions of lower and higher pressures were observed northwest and southeast of Beijing, respectively, in summer. The relative humidity near Beijing was higher in fall and winter, but lower in spring and summer. These differences may explain the seasonal dependence of the relationship between air pollution and the local meteorological variables. Our analysis showed that the temperature inversion in the lower troposphere played an important part in the occurrence of air pollution under stagnant weather conditions.Some results from this study are based on a limited number of events and thus require validation using more data.展开更多
基金funded by The National Natural Science Foundation of China(NSFC)(82170256)Guangdong Major Project of Basic and Applied Basic Research(2023B0303000005)+3 种基金The National Key Research and Development Program of China(2018YFA0108700)Guangdong Provincial Special Support Program for Prominent Talents(2021JC06Y656)Science and Technology Planning Project of Guangdong Province(2022B1212010010)the Special Project of Dengfeng Program of Guangdong Provincial People’s Hospital(KJ012019119).
文摘The cardiac microenvironment profoundly restricts the efficacy of myocardial regeneration tactics for the treatment of myocardial infarction(MI).A prospective approach for MI therapeutics encompasses the combined strategy of scavenging reactive oxygen species(ROS)to alleviate oxidative stress injury and facilitating macrophage polarization towards the regenerative M2 phenotype.In this investigation,we fabricated a ROSsensitive hydrogel engineered to deliver our previously engineered IL-1β-VHH for myocardial restoration.In mouse and rat models of myocardial infarction,the therapeutic gel was injected into the pericardial cavity,effectively disseminated over the heart surface,forming an in situ epicardial patch.The IL-1β-VHH released from the hydrogel exhibited penetrative potential into the myocardium.Our results imply that this infarct-targeting gel can adhere to the damaged cardiac tissue and augment the quantity of anti-IL-1βantibodies.Moreover,the anti-IL-1βhydrogel safeguards cardiomyocytes from apoptosis by neutralizing IL-1βand inducing M2-type polarization within the myocardial infarction regions,thereby facilitating therapeutic cardiac repair.Our results emphasize the effectiveness of this synergistic comprehensive treatment modality in the management of MI and showcase its considerable potential for promoting recovery in infarcted hearts.
基金supported by the National Natural Science Foundation of China grant number 41991282the National Major Research High Performance Computing Program of China grant number2016YFB0200800+1 种基金the National Natural Science Foundation of Chinagrant numbers 41630530 and 41706036the National Key Scientific and Technological Infrastructure project“Earth System Science Numerical Simulator Facility”(EarthLab)。
文摘Extending the atmospheric model top to high altitude is important for simulation of upper atmospheric phenomena,such as the stratospheric quasi-biennial oscillation.The high-top version of the Institute of Atmospheric Physics Atmospheric General Circulation Model with 91 vertical layers(IAP-AGCML91)extends to the mesopause at about 0.01 hPa(~80 km).The high-top model with a fully resolved stratosphere is found to simulate a warmer stratosphere than the low-top version,except near the South Pole,thus reducing its overall cold bias in the stratosphere,and significantly in the upper stratosphere.This sensitivity is shown to be consistent with two separate mechanisms:larger shortwave heating and larger poleward stratospheric meridional eddy heat flux in the hightop model than in the low-top model.Results indicate a significant influence of vertical resolution and model top on climate simulations in IAP-AGCM.
基金supported by the National Key R&D Program of China(Grant No.2017YFA0603502)the National Natural Science Foundation of China(Grant Nos.91644211 and 41575002).
文摘Cloud radiative kernels were built by BCC_RAD(Beijing Climate Center radiative transfer model)radiative transfer code.Then,short-term cloud feedback and its mechanisms in East Asia(0.5°S−60.5°N,69.5°−150.5°E)were analyzed quantitatively using the kernels combined with MODIS satellite data from July 2002 to June 2018.According to the surface and monsoon types,four subregions in East Asia-the Tibetan Plateau,northwest,temperate monsoon(TM),and subtropical monsoon(SM)—were selected.The average longwave,shortwave,and net cloud feedbacks in East Asia are−0.68±1.20,1.34±1.08,and 0.66±0.40 W m^−2 K^−1(±2σ),respectively,among which the net feedback is dominated by the positive shortwave feedback.Positive feedback in SM is the strongest of all subregions,mainly due to the contributions of nimbostratus and stratus.In East Asia,short-term feedback in spring is primarily caused by marine stratus in SM,in summer is primarily driven by deep convective cloud in TM,in autumn is mainly caused by land nimbostratus in SM,and in winter is mainly driven by land stratus in SM.Cloud feedback in East Asia is chiefly driven by decreases in mid-level and low cloud fraction owing to the changes in relative humidity,and a decrease in low cloud optical thickness due to the changes in cloud water content.
基金This research was supported by the National Major Research High Performance Computing Program of China[grant number 2016YFB0200800]the National Natural Science Foundation of China[grant numbers 41630530 and 41706036]the National Key Scientific and Technological Infrastructure project“Earth System Science Numerical Simulator Facility”(EarthLab).
文摘The quasi-biennial oscillation(QBO),a dominant mode of the equatorial stratospheric(~100–1 hPa)variability,is known to impact tropospheric circulation in the middle and high latitudes.Yet,its realistic simulation in general circulation models remains a challenge.The authors examine the simulated QBO in the 69-layer version of the Institute of Atmospheric Physics Atmospheric General Circulation Model(IAP-AGCML69)and analyze its momentum budget.The authors find that the QBO is primarily caused by parameterized gravity-wave forcing due to tropospheric convection,but the downward propagation of the momentum source is significantly offset by the upward advection of zonal wind by the equatorial upwelling in the stratosphere.Resolved-scale waves act as a positive contribution to the total zonal wind tendency of the QBO over the equator with comparable magnitude to the gravity-wave forcing in the upper stratosphere.Results provide insights into the mechanism of the QBO and possible causes of differences in models.
基金supported by the National Key R&D Program of China(2021YFC1523600)the National Natural Science Foundation of China(41930323&42371171)+2 种基金Basic Science Center for Tibetan Plateau Earth System(BSCTPES,41988101)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2022068)National Cultural Heritage Conservation Special Fund from National Cultural Heritage Administration,China.
文摘The origin and spread of agriculture facilitated a decline in human mobility and eventually led to a predominantly sedentary lifestyle globally,including on the Tibetan Plateau.Previous studies have proposed an evolution of prehistoric agriculture,from millet-based to barley-based farming.However,details regarding the process are vague.Here,we present diachronic changes in cropping structure from Xizang on the basis of a quantitative analysis of archaeobotanical remains from 12 sites located in southeastern Xizang.The advent of agriculture in Xizang began in the southeastern region around 4800 cal a BP and resulted in a quick spread of millet agriculture from the Hengduan Mountains to the Yarlung Zangbo River region.Subsequently,the introduction of barley and wheat to Xizang led to the transformation of millet-based farming into mixed farming after 3600 cal a BP.Eventually,around 3000 cal a BP,barley and wheat dominated across the entire Xizang with declining occurrences of millet.It took more than 600 years for barley and wheat to dominate in the Tibetan cropping system,which may reflect the time required for these exotic species to adapt physiologically to their new niche.In addition to the diachronic changes in crop farming,the ratio of barley to wheat and foxtail millet to broomcorn millet also varied at different elevations possibly due to local environmental variations and the crops’physiological requirements.
基金supported by the National Natural Science Foundation of China(Grant No.41930323)。
文摘Millet agriculture,which originated in northern China,alongside rice agriculture,have nurtured the Chinese civilization.Prehistoric manuring practices likely promoted and maintained sustainable millet agricultural production in the loess area of northern China.However,ongoing controversy exists regarding the indicators of prehistoric manuring intensity of foxtail millet(Setaria italica)and common millet(Panicum miliaceum).Here,we present the results of pot and field fertilization experiments on two millet types.Our findings suggest that manuring can significantly increase the δ^(15)N values of foxtail millet,and its δ^(15)N values increase with increasing manuring levels.The δ^(15)N values of foxtail millet leaves are systematically greater than those of grains by approximately 1.6‰.Manuring could have a long-term residual impact on increasing the δ^(15)N values of soil and millet crops.Combined with previous crop fertilization experiment results,we propose that the impact of manuring on the δ^(15)N values of non-nitrogen-fixing crops is roughly consistent.The δ^(15)N value and amount of manure are key factors determining the extent of change in plant δ^(15)N values.The millet grain δ^(15)N values can serve as reliable indicators of manuring practices.Finally,we provide an interpretive framework for assessing the correlation between manuring levels and the δ^(15)N values of archaeological millet remains.The δ^(15)N values of ancient millet grains suggest widespread and intensive manuring practices in prehistoric millet agriculture in northern China,spanning from the early Yangshao period to the Longshan period.
基金Supported by the National Natural Science Foundation of China(41475081,41530425,41425019,and 41661144016)State Oceanic Administration Public Science and Technology Research Funds Projects of Ocean(201505013)
文摘The present study investigates meteorological conditions for the day-to-day changes of particulate matter （PM） concentration in Beijing city during the period 2008-2015. The local relationship of PM concentration to surface air temperature, pressure, wind speed, and relative humidity displays seasonal changes and year-to-year variations. The average correlation coefficient with PMI0 in spring, summer, fall, and winter is 0.45, 0.40, 0.38, and 0.30 for air tem- perature; -0.45, -0.05, -0.40, and -0.45 for pressure; 0.13, 0.04, 0.53, and 0.50 for relative humidity; and -0.18, -0.11, -0.45, and -0.33 for wind speed. A higher correlation with wind speed is obtained when wind speed leads by halfa day. The heavily polluted and clean days, which are defined as the top and bottom 10% of the PM values, show obvious differences in the regional distribution of air temperature, pressure, and wind. Polluted days correspond to higher air temperature in all the four seasons, lower sea level pressure and anomalous southerly winds to the south and east of Beijing in spring, fall, and winter, and a northwest-southeast contrast in the pressure anomaly and anom- alous southerly winds in summer. Higher relative humidity is observed on polluted days in fall and winter. The pol- luted days are preceded by an anomalous cyclone moving from the northwest, accompanied by lower pressure and higher air temperature, in all four seasons. This feature indicates the impacts of moving weather systems on local meteorological conditions for day-to-day air quality changes in Beijing.
基金Supported by the National Natural Science Foundation of China(41475081,41530425,41425019,and 41661144016)State Oceanic Administration Public Science and Technology Research Funds Projects of Ocean(201505013)
文摘We compared the regional synoptic patterns and local meteorological conditions during persistent and non-persistent pollution events in Beijing using US NCEP–Department of Energy reanalysis outputs and observations from meteorological stations. The analysis focused on the impacts of high-frequency（period 〈 90 days） variations in meteorological conditions on persistent pollution events（those lasting for at least 3 days）. Persistent pollution events tended to occur in association with slow-moving weather systems producing stagnant weather conditions, whereas rapidly moving weather systems caused a dramatic change in the local weather conditions so that the pollution event was short-lived. Although Beijing was under the influence of anomalous southerly winds in all four seasons during pollution events, notable differences were identified in the regional patterns of sea-level pressure and local anomalies in relative humidity among persistent pollution events in different seasons. A region of lower pressure was present to the north of Beijing in spring, fall, and winter, whereas regions of lower and higher pressures were observed northwest and southeast of Beijing, respectively, in summer. The relative humidity near Beijing was higher in fall and winter, but lower in spring and summer. These differences may explain the seasonal dependence of the relationship between air pollution and the local meteorological variables. Our analysis showed that the temperature inversion in the lower troposphere played an important part in the occurrence of air pollution under stagnant weather conditions.Some results from this study are based on a limited number of events and thus require validation using more data.
